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The potential cytoprotective actions of a novel nicotinic agent 2,4-dimethoxybenzilidene anabaseine (DMXB) were investigated in differentiated PC12 cells and transected rat septal cholinergic neurons in vivo. In NGF-differentiated PC12 cells, removal of both NGF and serum led to cell loss, a reduced % of cells expressing neurites, the release of lactate dehydrogenase, and a decrease in total cellular protein. Cell loss was apparent within 24 h, and remained constant between 4–8 days post-NGF removal. NGF alone (100 ng/ml), DMXB (10 μM), but not nicotine (10 μM), prevented these cell and neurite losses. DMXB-induced cytoprotection was blocked by 1 μM mecamylamine. DMXB (1 mg/kg, ip) injected twice but not once per day protected cholinesterase-staining septal neurons from retrograde degeneration following unilateral fimbrial transections. The twice per day DMXB injection-protocol also decreased cell roundness among cholinesterase-staining cells in the lesioned septal hemisphere compared to saline-injected animals. These studies suggest that DMXB may exert cytoprotective activity in NGF-sensitive neuronal populations. © 1994 Wiley-Liss, Inc.  相似文献   
3.
A 21-year-old woman is reported with aplastic anaemia, who presented with pain in the leg. Rapid loss of sciatic nerve function followed. MRI showed irregular streaks of low intensity in the muscles of the pelvic region. A diagnosis of sciatic neuritis as initial symptom of clostridial myonecrosis was made.  相似文献   
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Recent advances in cardiovascular applications of magnetic resonance (MR) imaging and phosphorus-31 spectroscopy are reported. MR velocity mapping is a valuable adjunct to conventional imaging techniques, providing information on flow velocities as well as on absolute blood flow volume in the aorta and pulmonary arteries. Recently, ultrafast MR techniques have become available to evaluate myocardial perfusion with the aid of MR contrast agents as perfusion marker. Dynamic MR imaging is a powerful tool to assess cardiac function and ventricular mass. In particular, right ventricular function and mass can be evaluated with great accuracy, contributing to improved assessment of the significance of disease processes which may affect the right heart. The role of phosphorus-31 spectroscopy of the heart is expanding for the evaluation of ischemic myocardial disease and cardiomyopathies. The phosphocreatine to adenosine triphosphate ratio appears to be a marker of disease in patients with cardiac hypertrophy. In conclusion, MR imaging and phosphorus-31 spectroscopy is gaining widespread acceptance for evaluation of many cardiovascular disease processes.  相似文献   
6.
Although there are varied inheritance patterns in motor neuron disease (MND), the phenotype of MND is reported to be constant within these families, ie, cases of amyotrophic lateral sclerosis or primary lateral sclerosis do not occur in pedigrees with cases of spinal muscular atrophy. We describe four pedigrees whose members diverged in the phenotype of MND expressed. The intrafamilial variation of phenotype suggests a similar pathogenesis for some of the varied types of familial MND and the need for careful inquiry of family history in all patients with MND.  相似文献   
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In a multicenter study we selected 84 patients with fluctuating Parkinson's disease in order to evaluate the effects of controlled-release Sinemet 50/200 (=CR) versus standard Sinemet 25/100 (=STD) in an open-label 8-week titration period, followed by a double-blind, double-dummy 24-week treatment period. In contrast with previous double-blind studies, the efficacy of Sinemet CR proved to be significantly superior to that of Sinemet-STD according to NYUPDS and NUDS rating scales. This higher efficacy of Sinemet CR was not achieved at the expense of safety and/or tolerability. Actual total daily levodopa dosage in patients treated with Sinemet CR was increased by 33%; however, the plasma level of this dosage is calculated to be similar to that of the previous dosage of Sinemet-STD (bio-availability of Sinemet CR is 71%). Mean numbers of daily doses, off-hours, and off-periods were decreased significantly during Sinemet CR treatment. Although all other variables suggest that the number of on-hours had to be increased, statistical significance could not be reached in this respect.  相似文献   
8.
The aim was to investigate the bioactivity of a high-molecular weight human growth hormone, identified following molecular sieve chromatography of serum. Nine patients with pituitary disease and GH insufficiency were studied. All patients had non-detectable levels of immunoreactive GH, less than 0.2 micrograms/l, in diurnal serum profiles. GH bioactivity was determined before and after size-fractionation of serum. The bioassay is based on the finding that a rat lymphoma cell line, Nb2, proliferates in the presence of lactogens. GH and PRL immunoreactivities were measured by radioimmunoassays. Pronounced GH immunoreactivity was found in fractions of sera from 7 out of the 9 patients and of 2 of 4 control sera, particularly in fractions corresponding to the elution volume of high-molecular weight proteins (greater than 160 kD). PRL immunoreactivity was only detected in fractions corresponding to the elution volume of monomeric PRL. Unfractionated serum had a dose-dependent mitogenic effect on the Nb2 cells. GH-antibodies could not inhibit this effect. Fractions of serum obtained from the patients stimulated Nb2 cell division as well. The mitogenic effect of serum fractions could be inhibited by GH-antibodies. Thus, high-molecular weight GH circulating in patients with GH insufficiency were shown to exert a GH-specific bioactivity in vitro after size-fractionation.  相似文献   
9.
BACKGROUND. The authors examined prognostic factors in 158 cases of breast carcinoma with known mammographic tumor volume doubling times (DT). METHODS. The tumors were retrospectively reexamined histologically and flow cytometric analysis of DNA ploidy and S-phase fraction (SPF) was performed on archival paraffin-embedded material in each case. Life tables and Cox multivariate analyses were used for statistical evaluation of prognostic factors. RESULTS. In univariate analysis of survival data, clinical and pathologic stage, histologic grade, the presence of axillary lymph node metastases, and SPF were significant prognostic predictors, but mammographic DT and DNA ploidy were not. SPF also contributed prognostic information in the subgroup of carcinoma cases detected by screening. In a Cox multivariate analysis, SPF, the presence of axillary lymph node metastases, and Stage II-III disease (as opposed to Stage I disease) were independent significant predictors of survival. In univariate analyses of distant disease-free survival, clinical and pathologic stage, tumor size, histologic grade, the presence of involved axillary nodes, DT, and SPF all were significant prognostic factors. CONCLUSIONS. SPF, stage, and lymph node status were important prognostic factors in this patient material with predominantly small and node-negative breast carcinomas, whereas DNA ploidy and mammographic DT provided less prognostic information. The prognosis of carcinoma detected during screening did not differ significantly from that of breast carcinoma discovered otherwise in this selected patient group.  相似文献   
10.
BACKGROUND: Although no randomized controlled trial has assessed the effects of either compression sclerotherapy or ambulatory phlebectomy, both techniques are used to treat varicose veins worldwide. We performed a randomized controlled trial to compare recurrence rates of varicose veins and complications after compression sclerotherapy and ambulatory phlebectomy. METHODS: From September 1996 to October 1998, we randomly allocated 49 legs to compression sclerotherapy and 49 legs to ambulatory phlebectomy. Our primary outcome parameters were as follows: recurrence rates at 1 and 2 years and complications related to therapy. Eighty-two patients were included, of whom 16 were included with both of their legs. The number of treated legs was therefore 98, but two patients were lost to follow-up. RESULTS: One year recurrence amounted to 1 out of 48 for phlebectomy and 12 out of 48 for compression sclerotherapy (P<0.001); at 2 years, six additional recurrences were found, but then solely for compression sclerotherapy (P<0.001). Significant differences in complications occurring more in phlebectomy than in compression sclerotherapy therapy were blisters, teleangiectatic matting, scar formation, and bruising from bandaging. CONCLUSION: Our results show that ambulatory phlebectomy is an effective therapy for varicose veins of the leg. Recurrence rates are significantly lower than for compression sclerotherapy therapy. If varicose veins persist 4 weeks after compression sclerotherapy, it can be argued that to reduce the risk of future recurrence ambulatory phlebectomy should be considered as the better treatment option.  相似文献   
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