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71.
This is the first report of the analysis of the ATP-specific P2X1 receptor subunit in human hearts. We have examined homogenate samples of human left atria for the presence of P2X1 receptors using Western blots. Anti-P2X1 immunoreactivity was detected in populations of nondiseased atria as well as in atria from explanted hearts from patients with terminally failing heart conditions such as dilated cardiomyopathy. At least three groups of P2X1 immunoreactive proteins were detected in the Western blots with approximate molecular mass values of 50, 70, and 160 kDa. We report changes in expression of their 50 and 70 kDa components. These changes may be related to the type of deficit in these hearts since the changes have been observed in hearts with decreased ejection fractions characteristic of dilated cardiomyopathy.  相似文献   
72.
Recent evidence suggests that sexually transmitted diseases (STDs) enhance the transmission of human immunodeficiency virus (HIV) type 1. In 143 HIV-infected women enrolled in a university-based longitudinal HIV clinic over 16 months (mean), the STD point prevalence was examined at enrollment and the cumulative prevalence was calculated at follow-up. At enrollment, 35 women (25%) had > or = 1 STD. These included trichomoniasis in 16 women (11%); syphilis, 9 (6%); genital herpes, 8 (6%); gonorrhea, 5 (4%); chlamydia, 5 (4%); genital warts, 2 (1%); and pelvic inflammatory disease (PID), 1 (1%). STDs were found in 55 (42%) of the 125 patients who returned for at least one follow-up visit: trichomoniasis in 23 (18%); genital herpes, 20 (12%); gonorrhea, 9 (7%); syphilis, 7 (6%); genital warts, 7 (6%); chlamydia, 5 (4%); and PID, 4 (3%). Despite counseling at both enrollment and follow-up, these women had a very high cumulative prevalence of STDs, indicating persistent high-risk sexual behavior.  相似文献   
73.
A 29-year-old man was admitted to the hospital because of a high fever and dyspnea. He had a history of bronchial asthma and had had a bullectomy of the right lung at 15 years of age. He had visited a family physician because of fever and non productive coughing. Medications had no effect on his symptoms, and dyspnea developed. A chest X-ray film showed total collapse of the right lung, and he was referred to our hospital. Laboratory data showed eosinophilia and a high titer of IgE. Total obstruction of the right main stem bronchus by mucous plug was found during fiberoptic bronchoscopy. Aspergillus was detected by pathological examination of bronchial lavage fluid. Tests for aspergillus-specific IgE and IgG antibody were positive, as was immediate skin reactivity to Aspergillus. Allergic bronchopulmonary aspergillosis (ABPA) was diagnosed. Infusion and inhalation of a corticosteroid and fluconazole were effective; the symptoms resolved and X-ray findings improved. While migratory infiltration, proximal bronchiectasis and segmental or subsegmental atelectasis caused by a mucous plug are common X-ray findings in allergic bronchopulmonary aspergillosis, total collapse is rare.  相似文献   
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Evaluating the efficacy of neuroprotective drugs in rat models of focal cerebral ischemia has involved histological and behavioral batteries to examine treatment outcome. However, the behavioral tests used to date provide little insight into the nature of the neurological impairments. To provide an analysis of a possible "neglect" syndrome after occlusion of the middle cerebral artery, M. I. Posner's (1980) visual attentional paradigm was adapted for use in the rat. A paw-reaching task and a test of somatosensory "neglect" also were used to assess forelimb sensorimotor function. The lesion group displayed unilateral deficits; however, there was no evidence of attentional dysfunction. Results are consistent with the conclusion that the behavioral deficits identified arise from a somatosensory deficit rather than hemineglect due to dysfunctional spatial attention.  相似文献   
77.
PURPOSE: To evaluate the influence of prognostic factors in postoperative radiotherapy of NSCLC with special emphasis on the time interval between surgery and start of radiotherapy. METHODS AND MATERIALS: Between January 1976 and December 1993, 340 cases were treated and retrospectively analyzed meeting the following criteria: complete follow-up; complete staging information including pathological confirmation of resection status; maximum interval between surgery (SX) and radiotherapy (RT) of 12 weeks (median 36 days, range 18 to 84 days); minimum dose of 50 Gy (R0), and maximum dose of 70 Gy (R2). Two hundred thirty patients (68%) had N2 disease; 228 patients were completely resected (R0). One hundred six (31%) had adenocarcinoma, 172 (51%) squamous cell carcinoma. RESULTS: In univariate analysis, Karnofsky performance status (90+ >60-80%; p = 0.019 log rank), resection status stratified for nodal disease (R+ 相似文献   
78.
Phospholipase C (PLC) is a putative virulence factor of several pathogenic bacteria. We studied if exogenous PLC would perturb epithelial behavior in infected tissues. Gelatin and casein zymography of cell culture medium indicated that the broad-spectrum PLC of Bacillus cereus induced matrix metalloproteinase (MMP) production in epithelial cells of human skin (NHEK), human gingiva (HGE), and porcine periodontal ligament (PLE). In all three cell types, the strongest increase (ninefold) at 0.1 U/ml was seen in the MMP-9 (92-kDa gelatinase) activity, and the effect was dose dependent in the range of 0.1 to 1.0 U/ml. A relatively weaker increase (twofold) in MMP-2 (72-kDa gelatinase) was also observed in each cell type. PLC induction of MMP-3 (48-kDa stromelysin) was also seen in NHEK and HGE on gelatin and more sensitively for PLE by casein zymography (fivefold). Total gelatinolytic activity as measured by degradation of 14C-labeled denatured type I collagen increased by about 18-fold (NHEK), 12-fold (HGE), and 14-fold (PLE). Northern analysis showed a clear increase in the MMP-9, and a minor increase in MMP-3 mRNA levels but no significant increase in MMP-2 mRNA levels. Further studies with PLE revealed that MMP-9 induction by PLC progressively increased with the length of cell culture time in the absence of serum. PLC induction of MMPs was polar, with MMP-9 and MMP-3 secreted primarily in the apical direction and MMP-2 secreted mainly in the basal direction. The PLC effect was blocked by neomycin, an inhibitor of the phosphoinositol signal pathway. No significant effects were observed in MMP expression with the calcium ionophore A23187 or phospholipase A2. Morphologically, PLC treatment resulted in reduced contacts between the cultured cells and loss of the cell surface microvilli. These results suggest that PLC secreted by bacterial pathogens may disrupt epithelium of infected tissue and increase the subepithelial tissue destruction through induction of MMPs.  相似文献   
79.
R Sharma  CH Organ  ER Hirvela  VJ Henderson 《Canadian Metallurgical Quarterly》1997,174(6):629-32; discussion 632-3
HYPOTHESIS: To determine if a cause-effect relationship exists between crack cocaine use and duodenal ulcer perforation (DUP). PATIENTS AND METHODS: A retrospective study was conducted of all patients undergoing emergency surgical management for peptic ulcer disease over a 6-year period at a large inner-city municipal teaching hospital. The hospital records of 78 consecutive patients presenting with complications of peptic ulcer disease between April 1990 and April 1996 were reviewed. Group A (n = 24) consisted of patients with confirmation of crack cocaine usage within 8 hours of clinical presentation; group B (n = 54) consisted of patients with no antecedent history of crack cocaine use. Demographic data, timing of drug use, clinical presentation, laboratory and radiographic findings, toxicology screening, operative findings, and postoperative course were compared between the two groups. RESULTS: Both groups revealed a similar gender distribution, tobacco use, prior peptic ulcer symptoms, and laboratory findings. Group A patients were younger (t test, P = 0.01) and more likely to present with perforation, whereas patients in group B presented with a combination of symptoms (chi square, P = 0.03). Duodenal ulcer perforation was present in 75% of patients in group A compared with 46% of patients in group B (chi square, P = 0.04). Group B patients had a significantly longer hospital stay compared with those in group A (t test, P = 0.01). Both crack cocaine and alcohol are independent predictors of duodenal ulcer perforation. CONCLUSIONS: Patients with recent use of crack cocaine and/or alcohol are more likely to present with duodenal perforations. Although a temporal association between crack cocaine use and duodenal ulcer perforation was demonstrated, this study does not confirm a cause-effect relationship. A prospective cohort study is needed to clarify the pathogenesis of this potential cause-effect relationship.  相似文献   
80.
The growth-promoting activity of PDGF-BB was studied on the adult osteoclasts in the present study. The PDGF receptor beta was detected on the osteoclast membrane through immunohistochemistry (LSAB method) and immunomicroscopy. The PDGF-BB was exerted on the osteoclasts that adhered to the bone slice at concentrations of 0, 10, 20, 30, and 40 ng/ml. The volume of Howship's lacuna augmented significantly and the number of resorption pits also increased with its dose (p < 0.01). The activity of both total acid phosphatase (ACP) and tartrate-resistant acid phosphatase (TRAP) increased significantly. These results suggest that PDGF-BB promotes adult osteoclastic bone resorption directly through PDGF receptor beta and is believed to play important roles in the bone healing process and reconstruction.  相似文献   
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