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41.
James D. Geyer Louis B. Nabors Lindy E. Harrell Camilo R. Gomez 《Journal of neuroimaging》1997,7(4):244-247
A 52–year–old woman presented with a clinical picture consistent with bacterial meningitis 3 years after functional endoscopic sinus surgery. Diagnosis of a cerebrospinal fluid (CSF) fistula was made clinically, and the site of the fistula was confirmed using magnetic resonance cisternography. The utilization of this technique in the diagnosis of CSF disorders is gaining popularity. Its usefulness in the context of other imaging modalities is discussed. 相似文献
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健侧颈7移位治疗臂丛神经根性撕脱伤最佳时间选择的实验研究 总被引:11,自引:7,他引:4
健侧颈7移位治疗臂丛神经根性撕脱伤手术分第一阶段(健侧颈7移位到移植神经),第二阶段(移植神经另一端移植修复患侧神经),二次手术间隔多少时间才能获得最好的神经再生?选用SD大鼠及健侧颈7移位的实验模型,按二次手术间隔时间的不同(0、1、2、3、4、8、16周)分成7组,在第二次术后12周,进行电生理测定肌张力恢复率及组织切片的形态学观察,结果证实二次手术最佳间隔时间为4~8周.此结果可提供临床参考. 相似文献
44.
Louis F. McIntyre MD 《Operative Techniques in Sports Medicine》1997,5(4):233-237
Multidirectional shoulder instability is a common affliction and is increasingly recognized as a debilitating condition in young, athletic patients. Most patients with this condition are in their third decade and have a history of macrotrauma or repetitive microtrauma. Complaints range from frank instability to instability with pain, or to pain alone. These patients may display clinical signs of instability, impingement, or both on physical examination. Generalized ligamentous laxity or shoulder laxity alone are usually present. A positive sulcus sign remains the most sensitive clinical test in distinguishing these patients, even though no data is available on the sensitivity or specificity of this examination. The greater majority of patients are successfully treated with an exercise program stressing rotator cuff and scapular stabilizer strengthening. When patients do not respond to conservative treatment, open capsular shift has been recommended to restore joint stability. Early successes with the arthroscopic treatment of anterior shoulder instability have led to the development of similar procedures for the treatment of multidirectional instability. This paper describes an arthroscopic, multiple suture capsulorrhaphy for the treatment of multidirectional shoulder instability, which is a modification of the procedure advocated by Caspari and reviews the 2-year results of the first 19 patients treated. 相似文献
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Magali Louis Anne France Dekairelle Jean-Luc Gala 《Clinical chemistry and laboratory medicine》2004,42(12):1364-1369
Risk factors for cardiovascular diseases and venous thromboembolism involve both acquired and hereditary conditions. Among the latter, mutations in genes coding for coagulation factors (factor V Leiden [Arg506Gly], G20210A in the 3'-untranslated region of factor II ) and variant C677T of the methylenetetrahydrofolate reductase (MTHFR ) are often involved and co-inherited. These three factors were genotyped simultaneously in the same 96-well plate, using a real-time polymerase chain reaction (PCR) Taqman assay and minor groove binding DNA oligonucleotides (MGB probes). While primers and MGB probes matched their corresponding single nucleotide polymorphism (SNP), the real-time MGB program was identical for each target gene. Homozygous wild-type (WT; -/-), heterozygous (+/-) or homozygous (+/+) variants (n = 362) were selected for factor V (n = 115, with -/-, 40; +/-, 40; +/+, 35), factor II (n = 122, with -/-, 60; +/-, 60; +/+, 2), and MTHFR (n = 120, with -/-, 40; +/-, 40; +/+, 40), according to the results of conventional PCR-restriction fragment length polymorphism (PCR-RFLP), but the allelic discrimination was performed blind. Results of the real-time MGB and PCR-RFLP assays were identical. This new assay was easy and fast with high throughput, without risk of molecular carryover, and cost-effective for laboratories utilizing the Taqman or related fluorescence reading methods. These advantages make it particularly suitable for large-scale combined genotyping of several polymorphisms in the routine setting. 相似文献
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49.
Calcium antagonists inhibit positive chronotropic responses to alpha 1-adrenoceptor activation in rat isolated atria 总被引:1,自引:0,他引:1
Positive chronotropic responses of rat isolated atria to phenylephrine were reduced by propranolol (0.3 microM) and the residual response was further depressed by the selective alpha 1-adrenoceptor antagonist prazosin (1 nM) but not yohimbine (10 nM), confirming that a component of the response to phenylephrine was due to activation of alpha 1-adrenoceptors. When beta-adrenoceptors were blocked by propranolol, the positive chronotropic response to phenylephrine was enhanced by increasing the calcium concentration and by the calcium channel activator Bay K 8644 (0.1 microM), whereas the response was decreased by lowering the calcium concentration and by the calcium antagonists verapamil (10 nM), nifedipine (10 nM) and diltiazem (100 nM). In the presence of prazosin, when phenylephrine acts only on beta-adrenoceptors, calcium antagonists had no effect on the response. In rat isolated aortic strips in a calcium-free, high K+ (40 mM) solution, verapamil (10 nM), nifedipine (10 nM) and diltiazem (100 nM) shifted the calcium-induced contraction curves to the right, but prazosin (10 nM) had no effect, indicating that it is not a calcium antagonist. The calcium antagonists in the concentrations stated above had no effect on phenylephrine-induced contractions of rat aortic strips in normal Krebs-Henseleit solution, indicating that they did not block alpha 1-adrenoceptors in these concentrations. Taken together, these data suggest that the positive chronotropic effect of phenylephrine resulting from activation of alpha 1-adrenoceptors involves an increased influx of calcium through channels that are sensitive to organic calcium antagonists. 相似文献
50.