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991.
Traumatology of the alar ligaments   总被引:2,自引:0,他引:2  
A postmortem study of craniocerebral traumas of varying severity was done to determine the pattern of injury of the alar ligaments. It was found that in the entire group of patients (n = 30) the alar ligaments were ruptured or suffused with blood 11 times. No close relationship was found between the massive nature of the cranial trauma and the severity of the injury of the alar ligaments. In some cases the alar ligaments were not at all involved even though the skull had suffered extensive osseous lesions, whereas on the other hand the ligaments were injured even though only soft parts had been involved (e.g., haematoma or dehiscent wounds of the scalp). Ruptures of the alar ligaments were typically involved in extended ruptures of the ligamentous apparatus (see Figure 6a involving the ligamentum apicis dentis, ligamentum transversum atlantis, m.atlanto-occipitalis anterior, m.tectoria, m.atlanto-axialis anterior et posterior). In some cases the pattern of injury of the alar ligaments was found to be decisive in enabling reconstruction of the course of the accident. Damage to the alar ligaments near the dens axis represent rotation injuries. On the other hand, insertion tears out of the condyli occipitales must be related to a lateral thrust tendency in indirect fracture of the skull (bursting fracture). Within this overall framework a new mechanism of fracture of the condylus occipitalis is described. As a matter of principle, the alar ligaments can become involved in consequence of rotation, traction and compression of the cranium.  相似文献   
992.
993.
A study of intravenous (i.v.) cannula usage for medical emergencies admitted to hospitals in the Newham Health District was undertaken during two defined periods (24 and 35 days). Almost half the cannulas inserted (47%) were not flushed following an initial bolus injection of heparinized saline. The duration that cannulas remained in a vein ranged from 24 hours to 8 days (median 2 days) and inflammation around the cannula site was related to the length of time since insertion but unrelated to whether the cannula was flushed regularly or to the type of fluid used. Our findings indicate a substantial wastage of i.v. cannulas due to difficulties with insertion and suggest that isotonic saline, without heparin, is effective in maintaining cannula patency for 48 hours. It is concluded that these findings are not unique to the Newham Health District and worthwhile financial savings should be achieved throughout the NHS if clinicians reconsider the indications and use of i.v. cannulas for their patients.  相似文献   
994.
Results of prevention programs with adolescents   总被引:3,自引:0,他引:3  
Programs for preventing smoking and alcohol and drug abuse have radically changed in the past decade. Instead of being regarded as a health or discipline problem that involves only a few deviant adolescents, drug use has begun to be viewed as social behavior that is functional for adolescents, not capricious, and is normative for that population. The most successful prevention programs have sought to delay the onset of tobacco use. Based on theoretical and etiological research, these programs target factors that have repeatedly been predictive of adolescent smoking, alcohol and drug use. The programs teach adolescents (1) why people their age smoke tobacco or use alcohol and drugs; (2) how these meanings get established by peers, older role models and advertising; (3) how to resist these influences to smoke or to use alcohol and drugs; and (4) life skills and competencies to counterbalance the functions that drug use serves. Because of the association with the onset of smoking and the onset of using other drugs, these strategies are being studied for alcohol use and other drugs. In addition, elected peer leaders are trained to conduct these activities with their classmates and act as new role models for non-use. Evaluations of these approaches are optimistic. Studies in northern California and Minnesota reveal 50-70% reductions in the onset of smoking. Botvin's 'Life Skills Training' program demonstrates success in delaying heavy alcohol and marijuana use.  相似文献   
995.
Summary: Fifty-seven isolates of Basidiobolus from reptiles and amphibians, and 7 other obtained from the American Type Culture Collection (ATCC) in Maryland were studied for their extracellular enzyme activities on solid media. The Conidiobolus isolates studied included 4 recovered from Nigerian soil and additional 4 obtained from the ATCC All these isolates produced active extracellular lipase and protease and failed to exhibit amylase, deoxyribonuclease and ribonuclease activities. The significance of the findings is discussed.
Zusammenfassung: Fünfundsiebzig Basidiobolus-Isolate aus Reptilien und Amphibien und sieben weitere aus der American Type Culture Collection (ATCC) in Maryland wurden auf Aktivtäten extrazellulärer Enzyme auf festen Medien untersucht Die untersuchten Conidiobolus-Isolate schlossen vier aus nigerianischen Böden und vier weitere aus der ATCC ein. Alle Isolate zeigten extrazellulär Lipase- und Proteaseaktivität Amylase-, Desoxyribonuclease- und Ribonucleaseaktivität war jedoch nicht nachzuweisen. Die Bedeutung dieser Befunde wird diskutiert.  相似文献   
996.
M.A. Sabbahi  E.M. Sedgwick   《Brain research》1987,423(1-2):125-134
The H-reflex of 120 soleus motoneurons was recorded using fibre EMG. The recovery profile of these motoneurons was studied during monitoring surface H-reflex records in 28 adult subjects. The spectrum of motoneurons tested was homogeneous with two extremes of neurons having different characteristics. A motoneuron population (forming about 69% of our sample) had a high threshold level for electrical stimuli, short recovery time, and short recovery fringe time (called type A). A second population of motoneurons (forming about 20-30% of our sample) had a low threshold level for electrical stimuli, long recovery fringe time (called type B). During an isometric muscle contraction every motoneuron showed an early shift in recovery time (i.e. each had a shorter recovery time) with shortened recovery fringe time. These changes were larger for motoneurons type B than motoneurons type A. With paired identical electrical stimuli of varying interstimulus intervals a motoneuron may fire in response to the conditioning and test stimuli giving an H2, but not in response to both stimuli. This occurred for interstimulus intervals of 4-11 ms. A strong inhibition period was recorded with interstimulus intervals of 12-80 ms in which all motoneurons did not show any recovery. Most motoneurons recovered in orderly fashion between 80 and 300 ms of interstimulus interval, and this recovery coincided with the fast recovery recorded in surface H-reflex. All motoneurons were recovered by 3000 ms of interstimulus intervals. These findings emphasize the importance of eliciting the H-reflex every 3-5 s in H-reflex methodology in order to be assured that all excited motoneurons have been recovered.  相似文献   
997.
Two hundred and thirty pregnancies were studied in 196 diabetic women. Seven women with babies found to have major malformations had a higher median first trimester haemoglobin A1 (12.9%) than the median HbA1 (10.8%) in those with normal babies (p = 0.06). No relationship was found between the occurrence of minor malformations and first trimester maternal haemoglobin A1. Two of the seven congenital malformations were diagnosed antenatally at a time when therapeutic abortion could be offered. Expert antenatal ultrasound scanning should be offered to all pregnant diabetic women as poor glycaemic control at the time of conception and organogenesis, as evidenced by raised first trimester HbA1, predisposes to congenital malformation.  相似文献   
998.
Lymphangitis carcinomatosis has a grave prognosis. We report a case from carcinoma of the breast that responded completely and durably to chemotherapy.  相似文献   
999.
1000.
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