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31.
Perineural hemangiomas in the upper extremity have been the subject of few reports. We found only eight such cases reported in the literature. We report four additional cases in which there were neurologic symptoms. The specific diagnosis of cavernous hemangioma was not made preoperatively in any of the patients. The greater the extent of intrafascicular involvement, the more difficult is total eradication of the hemangioma.  相似文献   
32.
Two hundred aneurysms of the abdominal aorta were treated surgically from 1980 to 1987 by the same surgeon. There were 187 men and 13 women whose mean age was 66.1 years. Nine patients were 80-years-old or more. Eighty-seven percent of patients had preoperative risk factors, 30% of which were coronary artery disease. The operative approach was through a transverse laparotomy in 188 patients compared to 11 midline incisions and one lumbotomy. An aortoaortic tube was inserted in 87 patients, a bifurcated prosthesis in 99, and a tube bypass in 14. Five patients (2.5%) died within the 30 day perioperative period. Death was due to colonic necrosis, right heart chamber thrombosis, renal failure after repeat operation for acute lower limb ischemia, and myocardial infarction associated with renal and respiratory failure. The morbidity rate was 15.7% (31 patients) and included seven neurologic accidents, four respiratory complications, five ischemic events of the lower limbs requiring reoperation and one amputation, four cardiac complications, two renal failures, one reversible colonic ischemia, one revision for incomplete hemostasis, one phlebitis, one sliding syndrome, and five minor infections or cutaneous complications. Mean duration of hospital stay was 10.9 days. These results confirm that direct operation on aortic aneurysms can be performed in patients from all age groups and even with associated diseases. A rapid, simple technique based on a transverse approach, minimal dissection and insertion of aortoaortic tubes, whenever feasible, appears to reduce combined mortality-morbidity.Presented at the Annual Meeting of the Societé de Chirurgie Vasculaire de Langue Française, May 20–21, 1988, La Grande Motte, France.  相似文献   
33.
Because the distinction between gliosis and low-grade astrocytoma may prove difficult by routine light microscopy, we evaluated the silver nucleolar organizer region (AgNOR) technique in making this distinction. The AgNOR impregnation was performed on formalin-fixed, paraffin-embedded tissue from 49 central nervous system (CNS) biopsies: eight normal brain, 14 gliosis, 14 grade 2 astrocytoma (Daumas-Duport scale), two grade 4 astrocytoma, nine medulloblastoma, one metastatic carcinoma, and one choroid plexus papilloma. Quantitative and qualitative differences were found between gliosis and low-grade astrocytomas. In gliosis, AgNOR counts averaged 1.18 +/- 0.11 (SD) AgNOR/nucleus, while in low-grade astrocytomas AgNOR counts averaged 2.22 +/- 0.39 (p less than 0.001). Compound AgNOR were frequent in 9/14 grade 2 astrocytomas and in both grade 4 astrocytomas, whereas compound AgNOR were extremely rare in cases of gliosis. Quantitative and qualitative differences were also found between normal cerebellar internal granular cells and medulloblastoma cells. Cerebellar granular cells averaged 0.90 +/- 0.10 AgNOR/nucleus whereas medulloblastoma cells had an average of 4.52 +/- 0.95 (p less than 0.001). Compound AgNOR were seen in all medulloblastomas but not in internal granular cells. These findings suggest that the AgNOR technique may be a useful adjunct in the diagnosis of CNS neoplasia.  相似文献   
34.
SJL/J mice challenged with myelin basic protein (MBP) in complete Freund's adjuvant (CFA) developed only mild chronic-relapsing experimental allergic encephalomyelitis (EAE) with very low incidence. However, treatment of challenged mice with anti-infeferonγ (IFN-γ) monoclonal antibody (mAb) determined severe disease in all cases. Similarly, in passive EAE, the addition of anti-IFN-γ to the in vitro MBP-activated cells at the time of transfer led to significant disease exacerbation in all recipients. The disease enhancing effect was observed only when the mAb was given at the time of active challenge or of passive transfer, but not at later times. Anti-interleukin-2 (IL-2) antibody had only a marginal effect in the active induction, but drastically reduced the manifestations of passive EAE, even when mixed with a disease-enhancing dose of anti-IFN-γ. These findings support the notion that IL-2 is required for disease induction whereas IFN-γ plays a disease-limiting role early in the development of EAE.  相似文献   
35.
Anomalously low affinities for the beta-1-adrenoceptor are seen for members of a series of para-substituted N-isopropylphenoxypropanolamines in which the substituent is able to conjugate with the aromatic ring. The energy of conjugation was calculated using the AM1 semiempirical molecular orbital method and appears to correlate with the loss of binding energy, and hence affinity for the receptor. This suggests that binding is associated with movement of the substituent out of the plane of the aromatic ring due to steric interference with the receptor. A previously unrecognized binding site for aromatic groups off the para position is also identified.  相似文献   
36.
The conceptual and methodological framework proposed by Doss (this issue) makes valuable suggestions for strategic choices in future research. This commentary addresses conceptual and terminological distinctions adopted by Doss, as well as his criticism of add-on/ dismantling studies. We also suggest research topics and methodological developments that could be integrated in Doss's framework to further expand understanding of therapeutic change.  相似文献   
37.
38.
Objectives: To determine whether the Mac‐technique test can detect kinking of the chest tube upon thoracostomy tube placement. Methods: This was a prospective observational study that was conducted October 2000 through October 2001 in an urban Level 1 trauma center. There were 103 consecutive nonrandomized adult trauma patients who required immediate tube thoracostomy during their initial resuscitation who were entered into the study. The Mac‐technique test was performed during standard tube thoracostomy insertion to the appropriate depth. The test involved grasping the external portion of the thoracostomy tube, turning it clockwise 180°, and then releasing the tube. If the tube spontaneously spun back to its original position, the test was considered positive, and the tube was considered kinked. If the tube did not spontaneously spin back and stayed in position upon release, the test was considered negative. Regardless of the results of this test, the tube was secured, and a postprocedure chest radiograph was obtained. The criterion standard for determining a kinked chest tube was its appearance on this chest radiograph. Results: A total of 103 chest tubes were placed by using the Mac‐technique test. The test was positive in eight placements; four tubes were kinked on chest radiograph. The Mac‐technique test was negative in 95 placements; four tubes were kinked on chest radiograph. The Mac technique had a sensitivity of 50% (95% confidence interval [CI] = 15.7% to 84.3%), a specificity of 95.8% (95% CI = 89.6% to 98.8%), a positive likelihood ratio of 11.9, a negative likelihood ratio of 0.52, and an odds ratio using Yates correction of 20.3 (95% CI = 4.1 to 102.1). Conclusions: On the basis of this study, a positive Mac‐technique test is useful to detect chest tubes that are likely to be kinked after insertion and before securing.  相似文献   
39.
40.
Parkin mutations account for the majority of familial and sporadic early onset Parkinson's disease (EOPD) cases with a known genetic association. More than 100 mutations have been described in the Parkin gene that includes homozygous, compound heterozygous, and single heterozygous mutations. We have designed a Parkin mutation genotyping array (gene chip) that includes published Parkin sequence variants and allows their simultaneous detection. The chip was validated by screening 85 PD cases and 47 controls previously tested for Parkin mutations. Similar genotyping microarrays have been developed for other genetically heterogeneous diseases including age-related macular degeneration. Here, we show the utility of a genotyping array for Parkinson's disease by analysis of 60 subjects from the Genetic Epidemiology of Parkinson Disease (GEPD) study that includes 15 early-onset PD case probands and 45 relatives.  相似文献   
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