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21.
During the last 10 years, several cases of myocardial infarction associated with anabolic steroid use have been reported. Postulated mechanisms to explain this association have included changes in lipid levels, the fibrinolytic system, and platelet aggregation. Clenbuterol is a beta 2-agonist with anabolic properties that has not been seen previously with myocardial infarction. We report a case of myocardial infarction in an otherwise healthy 26-year-old body-builder who recently used clenbuterol and anabolic steroids. In this case, synergistic effects of the two agents seem likely to have played a role in the infarct. The normal coronary arteriograms before any anticoagulant or thrombolytic therapy strongly suggest coronary spasm as the mechanism of the infarct. 相似文献
22.
VJ Robertson 《Canadian Metallurgical Quarterly》1995,75(3):223-32; discussion 233-6
BACKGROUND AND PURPOSE: Published research contributes to the knowledge base that distinguishes one discipline from another. More research is now published in the physical therapy journals, but concerns with the profession's knowledge base continue. SUBJECTS: The study examined citations from 78 clinical articles published and indexed on three thematic areas in Physical Therapy between 1951 and 1990. METHODS: Unique items and multiple-cited items were identified and counted and their sources ascertained. Linkages among multiple-cited items in each thematic area were identified and described. RESULTS: Most cited items were unique and not from the physical therapy literature. Few linkages were identified among the clinical articles. CONCLUSION AND DISCUSSION: The lack of evidence of cumulation or of coherence among the articles examined and the extent of reliance on non-physical therapy sources suggest that concerns with the knowledge base of the profession are well founded. 相似文献
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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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Bacterial phospholipase C upregulates matrix metalloproteinase expression by cultured epithelial cells 总被引:1,自引:0,他引:1
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
27.
The mouse renin locus (Ren-1d) exhibits specific patterns of tissue expression. It is expressed in kidney but not submandibular gland (SMG). This locus contains a negative regulatory element (NRE) and a cAMP responsive element (CRE) that share an overlapping sequence. In the kidney, CRE binding proteins (CREB) and NRE binding proteins (NREB) compete for binding to this sequence, with the CREB having a greater affinity. In the SMG, CREB is inactivated by an inhibitory protein, permitting NREB to bind to the sequence, thus inhibiting Ren-1d expression. We hypothesize that the competition between NREB and CREB for this sequence governs tissue-specific expression of mouse renin. We speculate that this may be a general paradigm that determines tissue-specific gene expression. 相似文献
28.
Z Shen M Mohiuddin H Yokoyama GR Reiss VJ DiSesa 《Canadian Metallurgical Quarterly》1996,112(5):1315-1318
Indefinite donor-specific tolerance to a cardiac allograft can be induced through pretransplantation intrathymic injection of donor spleen cells and a single intraperitoneal injection of antilymphocyte serum. This study was designed to determine whether this phenomenon was reproducible with grafts differing in either class I major histocompatibility complex only or class II MHC only. Donors of cells and hearts in all experiments were RP rats. Class I MHC disparate grafts were performed by placing an RP heart into a Lewis recipient, and class II disparate grafts were performed with RP donors and Wistar Furth recipients. Lewis (n = 10) and Wistar Furth (n = 10) recipients underwent intraperitoneal injection of 1 ml antilympocyte serum and intrathymic injection of 5 x 10(7) RP spleen cells. Three weeks later, heterotopic cardiac transplantation was done with a heart from an RP rat. Control rats had no pretreatment or received antilympocyte serum alone. Without pretreatment, RP hearts survived 7 to 9 days (mean 8 days) in Lewis recipients (n = 5) and 9 to 14 days (mean 12 days) in Wistar Furth recipients (n = 5). Antilymphocyte serum alone produced slight prolongation of graft survival. Lewis rats pretreated with class I disparate RP splenocytes and antilympocyte serum had graft survivals of 8 to 27 days (mean 14 days), not significantly different from the results with antilympocyte serum alone. Class II disparate RP grafts placed in pretreated Wistar Furth rats had significant prolongation of graft survival, with four of five grafts surviving longer than 60 days (p < 0.01 vs antilympocyte serum alone). These results suggest that a disparity at the class II locus of the major histocompatibility complex is critical for the induction of cardiac allograft tolerance after intrathymic inoculation of allogeneic cells. 相似文献
29.
The carcinoid endocardial plaque; an ultrastructural study 总被引:2,自引:0,他引:2
Ultrastructural studies disclosed that the plaque-like endocardial thickenings in three patients with the carcinoid syndrome were composed of smooth muscle cells embedded in a stroma that was rich in acid mucopolysaccharides, collagen, and microfibrils, but devoid of elastic fibers. The smooth muscle cells contained variable numbers of myofilaments and cisterns of rough surfaced endoplasmic reticulum, and their basement membranes were greatly thickened, reduplicated, and arranged in layers. The endocardial plaques appeared histologically and ultrastructurally similar regardless of their location in the heart. The smooth muscle cells in these plaques appear to have been derived from primitive mesenchymal cells, which normally are present in the subendocardial endothelial space. These observations are interpreted as indicating that the plaques develop as a result of healing of a superficial endocardial injury, which may be initiated by release of bradykinin from hepatic metastases of a carcinoid tumor. 相似文献
30.