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  • 1
    Electronic Resource
    Electronic Resource
    Nitrous oxide emissions from grass swards during the eighth year of elevated atmospheric pCO2 (Swiss FACE) (2003)
    Oxford, UK : Blackwell Science Ltd
    Global change biology 9 (2003), S. 0 
    Details
    ISSN: 1365-2486
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Energy, Environment Protection, Nuclear Power Engineering , Geography
    Notes: Emissions of N2O were measured during the growth season over a year from grass swards under ambient (360 μL L−1) and elevated (600 μL L−1) CO2 partial pressures at the Free Air Carbon dioxide Enrichment (FACE) experiment, Eschikon, Switzerland. Measurements were made following high (56 g N m−2 yr−1) and low (14 g N m−2 yr−1) rates of fertilizer application, split over 5 re-growth periods, to Lolium perenne, Trifolium repens and mixed Lolium/Trifolium swards. Elevated pCO2 increased annual emissions of N2O from the high fertilized Lolium and mixed Lolium/Trifolium swards resulting in increases in GWP (N2O emissions) of 179 and 111 g CO2 equivalents m−2, respectively, compared with the GWP of ambient pCO2 swards, but had no significant effect on annual emissions from Trifolium monoculture swards. The greater emissions from the high fertilized elevated pCO2Lolium swards were attributed to greater below-ground C allocation under elevated pCO2 providing the energy for denitrification in the presence of excess mineral N. An annual emission of 959 mg N2O-N m−2 yr−1 (1.7% of fertilizer N applied) was measured from the high fertilized Lolium sward under elevated pCO2. The magnitude of emissions varied throughout the year with 84% of the total emission from the elevated pCO2Lolium swards measured during the first two re-growths (April–June 2001). This was associated with higher rainfall and soil water contents at this time of year. Trends in emissions varied between the first two re-growths (April–June 2001) and the third, fourth and fifth re-growths (late June–October 2000), with available soil NO3− and rainfall explaining 70%, and soil water content explaining 72% of the variability in N2O in these periods, respectively. Caution is therefore required when extrapolating from short-term measurements to predict long-term responses to global climate change. Our findings are of global significance as increases in atmospheric concentrations of CO2 may, depending on sward composition and fertilizer management, increase greenhouse gas emissions of N2O, thereby exacerbating the forcing effect of elevated CO2 on global climate. Our results suggest that when applying high rates of N fertilizer to grassland systems, Trifolium repens swards, or a greater component of Trifolium in mixed swards, may minimize the negative effect of continued increasing atmospheric CO2 concentrations on global warming.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-2486.2003.00654.x
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  • 2
    Electronic Resource
    Electronic Resource
    Biomechanical evaluation of a new modular rod-screw implant system for posterior instrumentation of the occipito-cervical spine: in-vitro comparison with two established implant systems (2000)
    Springer
    European spine journal 9 (2000), S. 417-425 
    Details
    ISSN: 1432-0932
    Keywords: Key words Posterior instrumentation ; Occipito-cervical spine ; Biomechanical testing, in vitro
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Posterior instrumentation of the occipito-cervical spine has become an established procedure in a variety of indications. The use of rod-screw systems improved posterior instrumentation as it allows optimal screw positioning adapted to the individual anatomic situation. However, there are still some drawbacks concerning the different implant designs. Therefore, a new modular rod-screw implant system has been developed to overcome some of the drawbacks of established systems. The aim of this study was to evaluate whether posterior internal fixation of the occipito-cervical spine with the new implant system improves primary biomechanical stability. Three different internal fixation systems were compared in this study: the CerviFix System, the Olerud Cervical Rod Spinal System and the newly developed Neon Occipito Cervical System. Eight human cervical spine C0/C5 specimens were instrumented from C0 to C4 with occipital fixation, transarticular screws in C1/C2 and lateral mass or pedicle screws in C3 and C4. The specimens were tested in flexion/extension, axial rotation, and lateral bending using pure moments of ± 2.5 Nm without axial preload. After testing the intact spine, the different instrumentations were tested after destabilising C0/C2 and C3/C4. Primary stability was significantly increased, in all load cases, with the new modular implant system compared to the other implant systems. Pedicle screw instrumentation tended to be more stable compared to lateral mass screws; nevertheless, significant differences were observed only for lateral bending. As the experimental design precluded any cyclic testing, the data represent only the primary stability of the implants. In summary, this study showed that posterior instrumentation of the cervical spine using the new Neon Occipito Cervical System improves primary biomechanical stability compared to the CerviFix System and the Olerud Cervical Rod Spinal System.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s005860000173
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  • 3
    Electronic Resource
    Electronic Resource
    Load-displacement properties of the normal and injured lower cervical spine in vitro (2000)
    Springer
    European spine journal 9 (2000), S. 104-108 
    Details
    ISSN: 1432-0932
    Keywords: Key words Cervical spine ; Biomechanical testing ; Discoligamentous structures
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The objective of this study was to determine which discoligamentous structures of the lower cervical spine provide significant stability with regard to different loading conditions. Accordingly, the load-displacement properties of the normal and injured lower cervical spine were tested in vitro. Four artificially created stages of increasing discoligamentous instability of the segment C5/6 were compared to the normal C5/6 segment. Six fresh human cadaver spine segments C4-C7 were tested in flexion/extension, axial rotation, and lateral bending using pure moments of ± 2.5 Nm without axial preload. Five conditions were investigated consecutively: (1) the intact functional spinal unit (FSU) C5/6; (2) the FSU C5/6 with the anterior longitudinal ligament and the intertransverse ligaments sectioned; (3) the FSU C5/6 with an additional 10-mm-deep incision of the anterior half of the anulus fibrosus and the disc; (4) the FSU C5/6 with additionally sectioned ligamenta flava as well as interspinous and supraspinous ligaments; (5) the FSU C5/6 with additional capsulotomy of the facet joints. In flexion/extension, significant differences were observed concerning range of motion (ROM) and neutral zone (NZ) for all four stages of instability compared to the intact FSU. In axial rotation, only the stage 4 instability showed a significantly increased ROM and NZ compared to the intact FSU. For lateral bending, no significant differences were observed. Based on these data, we conclude that flexion/extension is the most sensitive load-direction for the tested discoligamentous instabilities.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s005860050219
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  • 4
    Electronic Resource
    Electronic Resource
    Whiplash-type neck distortion in restrained car drivers: frequency, causes and long-term results (2000)
    Springer
    European spine journal 9 (2000), S. 109-117 
    Details
    ISSN: 1432-0932
    Keywords: Key words Car accident ; Whiplash-type neck distortion ; Duration of complaints ; Injury mechanism ; Prognostic factors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract An analysis was made of 1176 whiplash-type neck distortions taken from a total of 3838 restrained car driver incident reports. The percentage of whiplash-type neck distortion among injured drivers increased from less than 10% in 1985 to over 30% in 1997. Most occurred in head-on crashes or crashes with multiple collisions; only 15% occurred in rear-end collisions. More than 1,000 questionnaires were sent to the injured to find out about the duration and type of complaints caused by their cervical spine injury. Although only 138 (12%) returned the questionnaire, which may not be a representative sample, a further analysis was carried out. Of the 138, 121 (88%) indicated that they had suffered or were still suffering from their symptoms. The percentages of the various complaints were as follows: pain (74%), tension (6%) and stiffness (5%) in the head (27%), neck (55%) and shoulder (8%). The duration of the complaints was longest after multiple collisions and when the onset of complaints was longer than 24 h after trauma. Women and elderly persons predominated slightly in the group with longer duration of complaints. A correlation between the severity of the accompanying injuries and duration of complaints was found. Lack of adequate follow-up for patients with less severe injuries posed considerable difficulties for this retrospective study. In order to better evaluate this problem, prospective studies are necessary, with documentation including diagnosis, treatments, complaint duration and type.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s005860050220
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  • 5
    Electronic Resource
    Electronic Resource
    Computer-assisted surgery in posterior instrumentation of the cervical spine: an in-vitro feasibility study (2000)
    Springer
    European spine journal 9 (2000), S. S065 
    Details
    ISSN: 1432-0932
    Keywords: Key words Computer-assisted ¶surgery ; Cervical spine ; Posterior instrumentation ; In vitro
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Transarticular C1/2 screws are widely used in posterior cervical spine instrumentation. The use of pedicle screws in the cervical spine remains uncommon. Due to superior biomechanical stability compared to lateral mass screws, pedicle screws can be used, especially for patients with poor bone quality or defects in the anterior column. Nevertheless there are potential risks of iatrogenic damage to the spinal cord, nerve roots or the vertebral artery associated with both posterior cervical spine instrumentation techniques. Therefore, the aim of this study was to evaluate whether C1/2 transarticular screws as well as transpedicular screws in C3 and C4 can be applied safely and with high accuracy using a computer-assisted surgery (CAS) system. We used 13 human cadaver C0-C5 spine segments. We installed 1.4-mm Kirschner wires transarticular in C1/2, using a specially designed guide, and drilled 2.5-mm pedicle holes in C3 and C4 with the assistance of the CAS system. Hole positions were evaluated by palpation, CT and dissection. Forty-eight (92%) of the 52 drilled pedicles were correctly positioned after palpation, imaging and dissection. The vertebral artery was not injured in any specimen. All of the 26 C1/2 Kirschner wires were placed properly after imaging and dissection evaluations. No injury to vascular or bony structures was observed. C1/2 transarticular screws as well as transpedicular screws in the cervical spine can be applied safely and with high accuracy using a CAS system in vitro. Therefore, this technique may be used in a clinical setting, as it offers improved accuracy and reduced radiation dose for the patient and the medical staff. Nevertheless, users should take note of known sources of possible faults causing inaccuracies in order to prevent iatrogenic damage. Small pedicles, with a diameter of less than 4.0 mm, may not be suitable for pedicle screws.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/PL00010024
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  • 6
    Electronic Resource
    Electronic Resource
    Beschleunigungsverletzung der HWS beim gurtgeschützten PKW-Fahrer (2000)
    Springer
    Der Unfallchirurg 103 (2000), S. 22-29 
    Details
    ISSN: 1433-044X
    Keywords: Schlüsselwörter PKW-Unfall • HWS Beschleunigungsverletzung • Beschwerdedauer • Verletzungsmechanismus • Prognostische Faktoren ; Key words Car accident • Acceleration related injury of the cervical spine • Duration of complaints • Injury mechanism • Prognostic factors
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary In an analysis of 3,838 restrained car drivers, the proportion of acceleration related injury of the cervical spine increased from under 10 % in 1985 to over 30 % in 1997. These injuries occurred mainly in the case of head-on or multiple collisions. Letters were sent to 1,136 of the injured persons, and of the 138 patients who returned the questionnaires, 121 (88 %) were still suffering from their symptoms. It was a question of pain (74 %), tension (6 %) and stiffness (5 %) in the head (27 %), neck (55 %) and shoulder (8 %) area. The duration of the complaints was the longest after multiple collisions. In addition to a slight influence of the accompanying injuries on the duration of complaints, the individual constitution seems to be an important determining factor. In order to resolve the difficulties of conducting of this retrospective study, prospective studies are necessary which include documentation of diagnosis, treatment protocols, duration and type of complaints.
    Notes: Zusammenfassung Bei einer Unfallanalyse von 3.838 gurtgeschützten, angeschnallten PKW-Fahrern stieg der Anteil der HWS Beschleunigungsverletzung von unter 10 % 1985 auf über 30 % 1997. Überwiegend traten diese bei frontalen oder mehrfachen Kollisionen auf; 1.136 dieser Verletzten wurden angeschrieben, um Dauer und Art eventueller Beschwerden zu ermitteln. Von den 138 Patienten, die den Fragebogen zurücksendeten, gaben 121 (88 %) das Auftreten von Beschwerden an. Es handelte sich dabei um Schmerzen (74 %), Verspannungen (6 %) und Bewegungseinschränkungen (5 %) im Bereich von Kopf (27 %), Nacken (55 %) und Schulter (8 %). Die Dauer der Beschwerden war am längsten nach mehrfachen Kollisionen und einem Beschwerdebeginn nach mehr als 24 h. Neben einem geringen Einfluß der Begleitverletzungen auf die Beschwerdedauer sind auch die individuelle Konstitution und Schmerzverarbeitung wesentliche Faktoren. Auch bei dieser retrospektiven Untersuchung bestanden erhebliche Schwierigkeiten hinsichtlich der Nachuntersuchung. Zur Lösung dieses Problems sind prospektive Studien mit strengen Protokollen bezüglich der Erfassung von Diagnosestellung, Behandlung, Beschwerdedauer und -art erforderlich.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001130050004
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  • 7
    Electronic Resource
    Electronic Resource
    Die Entstehung von Beckenringverletzungen im Straßenverkehr Medizinisch-technische Unfallanalyse (2000)
    Springer
    Der Unfallchirurg 103 (2000), S. 267-274 
    Details
    ISSN: 1433-044X
    Keywords: Schlüsselwörter PKW-Unfall ; Beckenringverletzung ; Verletzungsmechanismus ; Klassifikation ; Prävention ; Key words Car accident ; Pelvic injury ; Injury mechanism ; Classification ; Prevention
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Abstract During 1985 and 1993, 7,410 persons were injured in traffic accidents in the area of Hanover. Of these, 306 (4.1%) sustained a pelvic girdle injury. In 139 cases (45%), the pelvic girdle injuries were further classified (Pennal and Tile) and a technical reconstruction of the accident situation was performed. 52% were type A, 27% type B and 21% type C injuries. Some 47% of the casualties were vehicle occupants, 31% pedestrians, 12% motorcyclists and 10% cyclists. In restrained vehicle occupants pelvic girdle injuries occurred mostly in accidents with a delta-v of more than 30 km/h, whereas in unrestrained vehicle occupants, pedestrians and cyclists they also occurred with lower delta-v or collision speed. The percentage of type B and C injuries increased with higher velocities. In addition to further improvements in passive safety, lower collision speed or delta-v is necessary to reduce or prevent pelvic girdle injuries. The reconstruction of pelvic girdle injury mechanism in traffic accidents is possible, when both technical and medical parameters are considered.
    Notes: Zusammenfassung Zwischen 1985 und 1993 wurden 7.410 Verkehrsunfallverletzte im Großraum Hannover erfaßt; 306 (4,1%) erlitten eine Beckenringverletzung mit einem AIS〉2. In 139 (45%) Fällen erfolgte die Klassifikation der Beckenringverletzung nach Pennal und Tile und eine vollständige technische Rekonstruktion; 52% waren danach Typ-A-, 27% Typ-B- und 21% Typ-C-Verletzungen. Bei den Verletzten handelte es sich um 46% PKW-Insassen, 31% Fußgänger, 12% Motorradfahrer, 10% Fahrradfahrer und 1% LKW-Insassen. Die Beckenringverletzungen traten bei gurtgeschützten Fahrzeuginsassen fast ausschließlich bei einem Δ-v von über 30 km/h auf, dagegen bei ungeschützten Verkehrsteilnehmern (Fußgänger und Radfahrer) und bei nicht gurtgeschützten Fahrzeuginsassen auch schon bei Anprallgeschwindigkeiten bzw. Δ-v von 10–20 km/h. Bei höheren Geschwindigkeiten stieg der Anteil der B- und C-Verletzungen. Neben weiteren Verbesserungen der passiven Sicherheit ist zur Verminderung oder Vermeidung von Beckenringverletzungen eine Verringerung der “Unfallgeschwindigkeit” nötig. Unter Berücksichtigung aller technischen und klinischen Parameter wird eine Rekonstruktion des tatsächlichen Unfallmechanismus von Beckenringverletzungen ermöglicht.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001130050535
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  • 8
    Electronic Resource
    Electronic Resource
    Frakturen der oberen Extremität bei gurtgeschützten PKW-Frontinsassen Verletzungsart und -häufigkeit in Abhängigkeit vom Unfallmechanismus (2000)
    Springer
    Der Unfallchirurg 103 (2000), S. 364-370 
    Details
    ISSN: 1433-044X
    Keywords: Schlüsselwörter PKW-Unfall ; Armfraktur ; Klassifikation ; Verletzungsmechanismus ; Prävention ; Key words Car accident ; Fracture of the arm ; Injury mechanism ; Classification ; Prevention
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Abstract During 1985 and 1995, 3,260 restrained car drivers (1,228 front seat passengers) were injured in 9,380 crashes involving cars. 179 (5.5%) (front seat passengers: 53.4%) of those sustained fractures, of the arm. Among the 384 single fractures the hand (25%), wrist (23%) and forearm (23%) were affected most often, elbow (9%), upper arm (10%) and shoulder (10%) rather seldom. Half of the evaluated fractures of the long tubular bones were type A-fractures due to the AO classification and the other two quarters, respectively type B- and C-injuries in each case. 16% were open fractures. No considerable differences of the injury mechanism were found comparing drivers and front seat passengers. Since over half of all fractures resulted from a direct impact to the hand and/or arm, modifications are necessary in order to improve the energy absorption by means of padding the dashboard and the inner door. The use of side- and front-airbags could serve as an additional auxiliary equipment, as long as it doesn't induce a supplemental stress, through unfolding of the airbag.
    Notes: Zusammenfassung Bei 9.380 Unfällen mit PKW Beteiligung zwischen 1985 und 1995 im Großraum Hannover wurden 4.488 gurtgeschützte PKW-Frontinsassen (3.260 Fahrer, 1.228 Beifahrer) verletzt und 232 (5,2%) erlitten Frakturen der oberen Extremität (179 Fahrer, 5,5%), (53 Beifahrer, 4,3%). Von den 384 einzelnen Frakturen waren Hand (26%), Handgelenk (22%) und Unterarm (23%) am häufigsten betroffen, Ellbogen (9%), Oberarm (10%) und Schulter (10%) eher selten. Bei der Hälfte der evaluierten Frakturen der langen Röhrenknochen handelte es sich um Brüche des Typs A gemäß der AO-Klassifikation und zu je 1/4 um Typ B- und C-Verletzungen. Der Anteil der offenen Frakturen betrug 16%. Zwischen Fahrer und Beifahrer wurden keine wesentlichen Unterschiede in der Verletzungsentstehung beobachtet. Da über die Hälfte aller Frakturen im Rahmen eines Direktanpralles von Hand und/oder Arm erfolgen, sind Maßnahmen zur Prävention im wesentlichen in einer optimalen Energieabsorption durch Polsterung des Armaturenbrettes und der Türfläche zu sehen. Die Verwendung von Seitenairbags und auch von Front-Airbags könnten hier einen zusätzlichen Schutz liefern, sofern sie nicht im Falle einer Auslösung und zusätzliche Belastungen induzieren.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001130050551
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  • 9
    Electronic Resource
    Electronic Resource
    Ein Herpes-simplex-Virus Typ 1-induzierter „Tumor” im Vestibulum nasi (2000)
    Springer
    HNO 48 (2000), S. 147-151 
    Details
    ISSN: 1433-0458
    Keywords: Schlüsselwörter ; Herpesviren ; Immunsuppression ; Resistenzentwicklung ; Key words ; Herpes virus ; Immunosuppression ; Treatment resistance
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary Herpes simplex viruses are known to be among the most common disease-causing microorganisms. Their prevalence can exceed 90% depending on the socioeconomic status of the population. Since the number of immunocompromised patients has increased because of the increased incidence in the acquired immunodeficiency syndrome and an increase in organ transplantation, herpes virus infection may have a greater clinical significance. While treatment of otherwise healthy individuals will not usually cause any clinical problems herpes infection in an immunocompromised patient can have severe consequences. Additionally, development of viral resistance can be observed that may require alternative drugs in treatment. We present a case history of a man with a B-cell chronic lymphocytic leukemia that was associated with a very unusual herpes simplex virus infection in the nasal vestibule. Possible causes for the development of resistance in herpes infections and the use of famciclovir and forscarnet as two therapeutic alternatives to aciclovir are discussed.
    Notes: Zusammenfassung Herpes-simplex-Viren gehören weltweit zu den häufigsten Krankheitserregern des Menschen mit einer in Abhängigkeit vom sozioökonomischen Status vorhandenen Prävalenz von über 90%. Das Bild der Herpesinfektion hat mit Zunahme der aus unterschiedlichsten Gründen (Organtransplantation, AIDS etc.) immunsupprimierten Patienten deutlich an Vielfalt gewonnen. Während die Therapie des immungesunden Patienten i. allg. keine Schwierigkeiten bereitet, kann eine Herpesinfektion bei immunsupprimierten Patienten zu einem ernsten eine Behandlung erforderlich machenden Krankheitsbild führen. Außerdem werden Resistenzentwicklungen beobachtet, die eine Therapie mit alternativen Medikamenten erforderlich machen. Wir stellen einen Patienten mit einer sehr ungewöhnlichen Manifestation einer Herpes-simplex-Infektion im Vestibulum nasi im Rahmen einer chronisch-lymphatischen B-Zell-Leukämie vor. Die möglichen Ursachen einer Resistenzentwicklung bei Herpesviren werden diskutiert und mit Famciclovir und Foscarnet zwei therapeutische Alternativen zum Aciclovir vorgestellt.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s001060050023
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