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171.
Thirty-one black medical students attending five white medical schools were seen in individual interviews of one to two hours to evaluate their perceptions of racism in their medical school education. The interviews focused on racism experienced in high school, college, and medical school. Over one half of the population experienced racism during their high school and college education, while 30 of 31 subjects reported racist experiences in their medical school education. The students reported a variety of methods of coping with racist experiences and emphasized the importance of fellow minority students, faculty, and the minority office in coping with the stresses of racist experiences. Those offering counseling services to minority students should recognize the reality of racist experiences in medical education. 相似文献
172.
Two-hundred and ninety-five patients with angiographically demonstrated intracranial aneurysms presented to the Institute of Neurological Sciences, Glasgow over a 3-year period (1986-88). We have reviewed this group to assess the effect of changing patterns of management upon outcome. The overall mortality rate was 9.4%, and the surgical mortality rate was 4% in this selected series. Factors significantly associated with a poor outcome were: WFNS grades III-V on admission, presence of a haematoma on the first CT scan, delayed ischaemic deficit, and development of a post-operative haematoma. Seventy-six per cent of the patients who developed a delayed ischaemic deficit (nearly a third of those with recent subarachnoid haemorrhage) made a good recovery, in contrast to previous studies, and over two-thirds of those accepted in grades IV and V (28 patients) made a good recovery after surgery. Active management of patients in grades IV and V, and those with delayed ischaemia, together with prophylactic Nimodipine therapy and selective early surgery, offers the best prospect for further improvement in outcome after aneurysmal subarachnoid haemorrhage. 相似文献
173.
174.
Bo Cui Stewart P. Johnson Nancy Bullock Francis Ali-Osman Darell D. Bigner Henry S. Friedman 《生物医学研究杂志》2010,24(6):424-435
Glioblastoma multiforme (GBM) is the most aggressive primary brain tumor in adults. Current therapy includes surgery, radiation and chemotherapy with temozolomide (TMZ). Major determinants of clinical response to TMZ include methylation status of the O6-methylguanine-DNA methyltransferase (MGMT) promoter and mismatch repair (MMR) status. Though the MGMT promoter is methylated in 45% of cases, for the first nine months of follow-up, TMZ does not change survival outcome. Furthermore, MMR deficiency makes little contribution to clinical resistance, suggesting that there exist unrecognized mechanisms of resistance. We generated paired GBM cell lines whose resistance was attributed to neither MGMT nor MMR. We show that, responding to TMZ, these cells exhibit a decoupling of DNA damage response (DDR) from ongoing DNA damages. They display methylation-resistant synthesis in which ongoing DNA synthesis is not inhibited. They are also defective in the activation of the S and G2 phase checkpoint. DDR proteins ATM, Chk2, MDC1, NBS1 and gammaH2AX also fail to form discrete foci. These results demonstrate that failure of DDR may play an active role in chemoresistance to TMZ. DNA damages by TMZ are repaired by MMR proteins in a futile, reiterative process, which activates DDR signaling network that ultimately leads to the onset of cell death. GBM cells may survive genetic insults in the absence of DDR. We anticipate that our findings will lead to more studies that seek to further define the role of DDR in ultimately determining the fate of a tumor cell in response to TMZ and other DNA methylators. 相似文献
175.
176.
Presence of substance P and neurokinin 1 receptors in human sputum macrophages and U-937 cells. 总被引:7,自引:0,他引:7
P R Germonpre G R Bullock B N Lambrecht V Van De Velde W H Luyten G F Joos R A Pauwels 《The European respiratory journal》1999,14(4):776-782
Tachykinins such as substance P (SP) may be involved in the pathogenesis of inflammatory airway diseases such as asthma. This study investigated the presence of SP and its receptor in the differentiated macrophage-like U-937 cell line and in macrophages from sputum induced in healthy subjects (n=8). In situ hybridization with digoxigenin-labelled sense and antisense complementary ribonucleic acid (cRNA) probes was used to determine the expression of SP and its receptor (neurokinin (NK)1 receptor). SP-immunoreactive material was detected using a rabbit anti-SP antiserum and the alkaline phosphatase anti-alkaline phosphatase technique. Beta-preprotachykinin (PPT)-I messenger ribonucleic acid (mRNA) encoding SP, was detected using in situ hybridization in differentiated U-937 cells as well as in CD45+ human leukocyte antigen (HLA) DR+ sputum macrophages. The expression of the beta-PPT-I mRNA was increased in lipopolysaccharide (LPS)-stimulated U-937 cells. SP-immunoreactive material was found in differentiated U-937 cells and in CD68+ sputum macrophages. NK1 receptor mRNA was detected in differentiated U-937 cells and sputum macrophages. Incubation of U-937 cells with SP considerably increased the expression of NK1 receptor mRNA. This study demonstrates that human monocytes/macrophages express substance P and that this expression is upregulated by lipopolysacharide. Human monocytes/macrophages also express neurokinin1 receptor messenger ribonucleic acid, suggesting an autocrine effect of substance P on these cells. 相似文献
177.
PURPOSE: To illustrate the utility of gallium scintigraphy in the diagnosis and management of orbital lymphoma. METHODS: A patient with an orbital lymphoma is reported. The results of the computed tomography scan and gallium scan are reviewed. RESULTS: Although the orbital lymphoma was readily visible on the gallium scan, it was poorly visualized on the computed tomography scan, which was interpreted as normal. CONCLUSION: Gallium scanning is a valuable adjunct in the diagnosis and management of orbital and systemic lymphoma. 相似文献
178.
A 35-year-old female with pyoderma gangrenosum developed paraparesis with a sensory level at L1. Three months later she complained of diplopia and was found to have bilateral internuclear ophthalmoplegia with exotropia and no ocular convergence. The term Webino syndrome has been coined to design this set of neuro-ophthalmologic findings. Although it was initially attributed to lesions affecting the medial longitudinal fasciculus and the medial rectus subnuclei of the oculomotor complex in the midbrain the exact location of the lesion is still disputed. In the present case both myelopathy and Webino syndrome were probably due to vascular occlusive disease resulting from central nervous system vasculitis occurring in concomitance to pyoderma gangrenosum. 相似文献
179.
180.
This study was designed to confirm the identity of the enzyme involved in the appearance of a nuclear metabolite of 6a-methyl progesterone (6MP) in mouse kidney but not in prostate-seminal vesicle. 6MP and progesterone competed for metabolism by the kidney enzyme. Using progesterone as substrate, the results of recrystallization of the product with 20a-hydroxy progesterone supported the identification of the enzyme as 20a-hydroxysteroid dehydrogenase (20aHSD). The enzyme had a substrate specificity similar to that reported for 20aHSD in other tissues. Renal enzyme activity was higher in female than in male CD-1 mice while activity was generally lower and without a sex difference in a random bred colony. Renal enzyme activity varied slightly with the estrous cycle, being highest at proestrus and lowest on day 2 of diestrus. Little enzyme activity was detected in prostate-seminal vesicles. It appears that 20aHSD is an important factor in regulating the differential presence of the 20a-metabolite of 6MP in kidney and prostate-seminal vesicle nuclei. 相似文献