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101.
102.

Purpose

A prospective, multicenter, randomized study was done to test the hypothesis that neoadjuvant androgen withdrawal decreases the incidence of positive margins following radical prostatectomy for localized prostate cancer.

Materials and Methods

Observations were made of 213 patients randomized to undergo radical prostatectomy alone (101) or to receive a 12-week course of 300 mg. cyproterone acetate daily followed by surgery (112). Groups were similar at baseline in terms of clinical stage, serum prostate specific antigen and Gleason score. Of 192 patients available for efficacy analysis 9 had stage T1b, 8 stage T1c, 63 stage T2a, 36 stage T2b and 76 stage T2c disease.

Results

One or more positive surgical margins were found in 59 of 91 patients (64.8 percent) in the surgery only group compared to 28 of 101 (27.7 percent) in the cyproterone acetate group (p = 0.001). Patients who received preoperative therapy had a statistically significantly lower rate of apical margin involvement than those who did not (17.8 versus 47.8 percent, respectively, p less than 0.0001). There was no statistically significant difference in surgical (p = 0.8645) or postoperative (p = 0.173) complications between the 2 groups.

Conclusions

Neoadjuvant androgen withdrawal with a 12-week course of 300 mg. cyproterone acetate daily results in a lower rate of positive margins without adversely affecting postoperative recovery. The impact on patient survival will be determined by long-term followup.  相似文献   
103.
The prevalence of microalbuminuria was assessed in 50 patients of non-insulin dependent diabetes mellitus. The mean age of patients was 52.1 ± 11.6 years and the duration of diabetes was 8.3 ± 6.8 years. Twenty (40%) patients had microalbuminuria. Microalbuminuria was more common in patients with a longer duration of diabetes (more than 5 years), a poor glycaemic control, and higher systolic blood pressure.KEY WORDS: Microalbuminuria, Diabetes mellitus, Diabetic nephropathy, Chronic renal failure  相似文献   
104.
Two 4-year-old monozygotic Chinese, female twins developed concordant childhood acute lymphoblastic leukemia (ALL) within an interval of about 2 weeks. Based on morphology and cytochemistry findings of the bone marrow blast cells, a diagnosis of ALL, L1 was made. Immunophenotyping showed the blast cells of both twins expressed similar antigens, i.e. HLA-DR, CD10, CD13, CD19, CD22 and CD34. Identical blood group, same HLA (human leucocyte antigen) genotype, sex and similar appearance suggest that the twins are monozygotic. Since the bone marrow leukemic cells of both twins were identical in morphology and expressed the same antigens with almost similar percentages of positivity, it is likely that the blast cells were derived from the same single clone. Based on the single clone hypothesis, the leukemogenic event must have arisen in utero in one twin and the cells from the abnormal clone then spread to the other twin via shared placental anastomoses.  相似文献   
105.
Incubation of N-nitrosodi[14C]methylamine with calf thymus DNA and an isolated rat liver microsomal fraction resulted in a transfer of 14C-label from N-nitrosodi[14C]methylamine to biological macromolecules present in the in vitro assay system. This transfer of 14C-label from N-nitrosodi[14C]methylamine to biological macromolecules, believed to represent a methylation process, was dependent on the integrity and concentration of rat liver microsomes added to the in vitro assay system, as well as on the time of incubation. A requirement for NADPH was also observed. A study of the kinetics of this transfer of 14C-label from N-nitrosodi[14C]methylamine to biological macromolecules in vitro yielded values for the apparent Km and Vmax of 0.18 mm and 2.56 pmol methyl groups transferred per milligram of nucleic acid per milligram of microsomal protein per minute, respectively. The transfer reaction was inhibited by exposure of microsomes to carbon monoxide or pretreatment of animals with phenobarbital, 3-methylcholanthrene, or 2,3,7,8-tetrachlorodibenzo-p-dioxin. The capability of other rat liver subcellular fractions to mediate the reaction was examined.  相似文献   
106.
107.
Paired helical filaments, the main structural components of the neurofibrillary tangles in Alzheimer disease, consist of phosphorylated tau protein. Because the levels and degree of phosphorylation are significantly higher in paired helical filament (PHF)-derived tau than in normal adult tau, and because phosphorylation of tau severely disrupts microtubule stability, it is postulated that tau phosphorylation is an important step in PHF formation. The kinases and/or phosphatases that act in vivo to help induce such a pathological state of tau, however, are not yet known. In this study we implicate the non-proline directed kinase MARK in PHF-tau phosphorylation, by virtue of its close intermolecular association with the phosphorylated Ser262 epitope on PHF-tau as assessed by fluorescence resonance energy transfer. Moreover, because this tight enzyme-substrate association is observed in neurofibrillary tangles in Alzheimer tissue, we suggest that PHF-tau phosphorylation may occur to some extent on assembled PHF filaments.  相似文献   
108.
Amyotrophic lateral sclerosis was once thought to be caused by persistent viral infection, partly because some patients with transmissible Creutzfeldt-Jakob disease showed prominent amyotrophy. However, in the past 15 years there has been little interest in the amyotrophy in prion diseases, and the possible link to amyotrophic lateral sclerosis has been eschewed. We analyzed case reports of prion disease published after 1968 for evidence of amyotrophy. We defined amyotrophy as clinically evident fasciculation buttressed by electromyographic results in some cases. We sought evidence of motor neuron degeneration at autopsy. Prion disease was proved by transmissibility, immunohistochemistry demonstration of protease-resistant prion protein, or finding a mutation in the prion protein gene. Amyotrophy was noted in 27 patients: 13 with sporadic Creutzfeldt-Jakob disease, 2 with familial Creutzfeldt-Jakob disease, and 12 with Gerstmann-Str?ussler-Scheinker disease. Of the 27, 23 showed clinical fasciculation and 10 had electromyographic evidence of denervation. The spinal cord was examined in 8 patients: 6 showed loss of motor neurons, 1 showed vacuolation of motor neurons, and 1 reported no abnormalities. Another 23 patients had typical histopathological characteristics but lacked molecular or biochemical proof of prion disease. The total number of patients with amyotrophy and proven prion disease that we identified was 50. This case review supports the belief that amyotrophy is occasionally a prominent feature of Creutzfeldt-Jakob disease and underscores the importance of documenting lower motor neuron function and the crucial role of examining the spinal cord at autopsy in cases of prion disease.  相似文献   
109.
110.
16例高原红细胞增多症 (简称高红症 )病人 ,在围术期我们针对该类患者其血液成分 ,微循环 ,血液流变学等方面发生的一系列生理或 /和病理性改变。采取了血液稀释和自体输血等相应的对策 ,取得了较好的手术麻醉效果 ,大大降低了高红症病人手术麻醉的危险性  相似文献   
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