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21.
Placebo controls play a critical role in the evaluation of any pharmacotherapy. This review surveys the placebo arm in 12 randomized controlled trials (RCTs) investigating burning mouth syndrome (BMS) and documents a positive placebo response in 6 of them. On average, treatment with placebos produced a response that was 72% as large as the response to active drugs. The lack of homogeneity in the use of placebos adds to the difficulty in comparing results and aggregating data. Future RCTs investigating BMS would benefit from larger sample sizes, adequate follow‐up periods, and use of a standard placebo.  相似文献   
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艾滋病合并隐球菌脑膜炎18例临床分析   总被引:6,自引:1,他引:6  
目的 提高对艾滋病 (AIDS)合并隐球菌脑膜炎的认识。方法 对赤道几内亚巴塔地区医院 18例AIDS合并隐球菌脑膜炎患者进行临床综合分析。结果  18例AIDS合并隐球菌脑膜炎患者的临床主要表现为 :发热、剧烈头痛、极度乏力、肢体痛、脑膜刺激征及消瘦与脱水等。脑脊液 (CSF)培养均为新型隐球菌生长 ;涂片及隐球菌多糖荚膜抗原 (ELISA法 )检测的阳性率分别为 77 8% (14/ 18) ,94 4% (17/ 18)。结论 隐球菌脑膜炎为AIDS常见机会性感染及主要致死病因之一。  相似文献   
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Primary osteogenic sarcoma of the skull is an exceedingly rare condition. An adult male patient is described, who had a painless swelling in the right forehead that had rapidly enlarged in the previous 6 months. Radiological investigations showed a large destructive mass lesion involving the right side of the frontal bone with extension into the frontal sinus, causing marked extradural compression of brain parenchyma. Histopathological examination confirmed the lesion to be primary osteogenic sarcoma.  相似文献   
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The concept that bone marrow (BM)-derived cells participate in neural regeneration remains highly controversial and the identity of the specific cell type(s) involved remains unknown. We recently reported that the BM contains a highly mobile population of CXCR4+ cells that express mRNA for various markers of early tissue-committed stem cells (TCSCs), including neural TCSCs. Here, we report that these cells not only express neural lineage markers (beta-III-tubulin, Nestin, NeuN, and GFAP), but more importantly form neurospheres in vitro. These neural TCSCs are present in significant amounts in BM harvested from young mice but their abundance and responsiveness to gradients of motomorphogens, such as SDF-1, HGF, and LIF, decreases with age. FACS analysis, combined with analysis of neural markers at the mRNA and protein levels, revealed that these cells reside in the nonhematopoietic CXCR4+/Sca-1+/lin-/CD45 BM mononuclear cell fraction. Neural TCSCs are mobilized into the peripheral-blood following stroke and chemoattracted to the damaged neural tissue in an SDF-1-CXCR4-, HGF-c-Met-, and LIF-LIF-R-dependent manner. Based on these data, we hypothesize that the postnatal BM harbors a nonhematopoietic population of cells that express markers of neural TCSCs that may account for the beneficial effects of BM-derived cells in neural regeneration.  相似文献   
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The present study investigated the expression and distribution of three isoforms of nitric oxide synthase (NOS) in different anatomical regions of the human stomach and in gastric neoplastic tissues by immunohistochemistry using specific antibodies. Intracellular localization of individual isoenzymes of NOS was detected in normal gastric mucosa. Gastric cancer tissues had a marked reduction of all three NOS isoforms expression. The expression of the endothelial NOS, neuronal NOS and inducible NOS in the tumor tissue was significantly lower than in normal gastric mucosa (P = 0.01, P = 0.02, P < 0.01, respectively). In the tumor tissue the expression of inducible NOS was significantly lower than the expression of both constitutive forms of NOS (P < 0.01). There was a tendency to higher expression of both constitutive forms of NOS in earlier stages T2 of the tumor compared to advanced T4 tumor. In contrast, the expression of inducible NOS was higher than in the advanced T4 tumor than in the earlier stages T2 of the tumor. The mapping of the expression of endothelial NOS, neuronal NOS and inducible NOS in human stomach showed higher expression of NOS isoforms in the distal third than in the proximal third of the stomach (P = 0.03, P = 0.04, P = 0.01, respectively). We conclude that there is greater expression of NOS in the stomach corpus and in antrum than in the proximal third of the normal human stomach mirroring the anatomical predilection of common pathological changes in this part of the human stomach. Furthermore, there was loss of the expression of individual isoenzymes in gastric neoplasms.   相似文献   
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A retrospective analysis of 28 patients who received therapy for squamous cell carcinoma of the buccal mucosa at the Massachusetts General Hospital from January 1962 through December 1976 is presented. The patients ranged in age from 42 to 78 years; the majority of patients presented with disease at 50 years or more. The proportion of females in this series (43 per cent) represented a dramatic increase compared with previous reports from other large centers. The 29 per cent rate of metachronous or synchronous second primary malignant disease is increased significantly over that expected for the general population. Uncontrolled disease above the clavicle continues to be the major site of therapeutic failure. The development of co-operative multicenter randomized prospective protocols to evaluate the efficacy of various combinations of current therapy methods in order to improve patient survival from this devastating disease are encouraged.  相似文献   
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