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991.
Multiple myeloma is associated with a susceptibility to bacterial infections, specifically for encapsulated organisms such as Streptococcus pneumoniae. However, severe bacterial infection as the initial presentation of this disease has been rarely reported. The most common presenting features are anemia, lytic lesions, hypercalcemia, and renal failure. We report two cases of pneumococcal bacteremia as the initial manifestation of an underlying multiple myeloma. The first case is of a 68-year-old woman with pneumococcal pneumonia and bacteremia, presenting with a white blood cell count of 900/microL and mild anemia. Further work-up disclosed monoclonal IgG kappa and 50% plasma cells in bone marrow. Her course was complicated by acute renal failure requiring hemodialysis. The second patient is a 57-year-old man presenting with acute pneumococcal meningitis and bacteremia. Due to prior bacterial epiglottitis, further work-up disclosed IgG lambda monoclonal spike and 40% plasma cells in bone marrow. Both cases responded to antibiotic therapy without complications. These two cases add to the few patients described in the literature with pneumococcemia as the first sign of multiple myeloma. Features that were common in most of these cases, and that should lead to a suspicion of myeloma in an otherwise asymptomatic patient, are S. pneumoniae bacteremia, leukopenia, mild anemia, history of prior bacterial infections, and indirect evidence of a paraproteinemia, such as increased total protein levels with low albumin.  相似文献   
992.
The objective of this study was to compare the properties of single smooth muscle cells enzymatically dispersed from the dog mesenteric arteries to the properties of similar cells functioning in tissue strips. The isolated cells remained relaxed in nominally Ca(2+)-free medium for about 1-2 h after exposure to 1 mM Ca2+ and like intact mesenteric artery rings did not contract spontaneously. Enzymatically dispersed cells maintained all the characteristic morphological features observed in strips of muscle prior to isolation except that the amorphous materials covering the smooth muscle cell surfaces (basal lamina) were absent after enzymatic dispersion. Addition of 100 mM KCl to these vascular muscle cells elicited maximal shortening in the presence but not in the absence of extracellular Ca2+ and KCl-induced cell shortening was prevented by 10(-7) M nifedipine indicating the presence of functional voltage-operated Ca2+ channels. However, in contrast to the vascular muscle strips, in which graded contractile responses were observed with increasing KCl concentrations, isolated vascular muscle cells underwent nearly maximal contraction at concentrations as low as 15 mM KCl. Both intact tissue and isolated cell preparations responded similarly to phenylephrine in a concentration-dependent manner and the responses were blocked by prazosin. In contrast to muscle strips, the isolated cells did not shorten in response to phenylephrine in Ca(2+)-free medium. Isolated muscle shortened in the presence of sarcoplasmic reticulum selective Ca2+ transport ATPase inhibitors, cyclopiazonic acid or thapsigargin. Ryanodine also caused contraction. We conclude that enzymatically dispersed smooth muscle cells from dog mesenteric arteries are potentially useful for studies of the regulation of smooth muscle contractility, but have significantly increased sensitivity to external K+, implying an altered membrane potential or voltage dependence of ion channels. Their impaired ability to contract to phenylephrine in Ca(2+)-free medium implies some alteration in intracellular Ca2+ stores of their coupling to cellular activation. These differences will affect how the data obtained from freshly isolated enzymatically dispersed vascular muscle cells may be extrapolated to cell studies in intact tissues.  相似文献   
993.
10C12, a human antibody F(ab')2, which specifically binds to the gamma-carboxyglutamic acid domain of factor IX/factor IXa (F.IX/IXa), interferes with all known coagulation processes in which F.IX/IXa is involved. In a rabbit model of carotid artery injury, intravenous administration of 10C12 or heparin decreased thrombosis dose dependently. The dose that resulted in a 90% reduction of thrombus mass (ED90) was a 30-microg/kg bolus of 10C12 or a 100-U/kg bolus plus 1.0 U x kg(-1) x min(-1) infusion of heparin. Heparin, at and below the ED90, significantly prolonged coagulation times and cuticle bleeding times. In contrast, 10C12 had no effect on coagulation or bleeding times at doses up to 4 times the ED90. To further evaluate the effect of 10C12 on bleeding, it was compared with heparin in a novel model of blood loss. At the ED90 of heparin, blood loss induced by a standardized injury to the vasculature of the rabbit tibia increased to more than 2 times that of saline controls. In contrast, the dose of 10C12 required to produce a similar increase in blood loss was more than 30 times the ED90. The antithrombotic potency and relative safety of this fully human antibody suggests that it may have therapeutic value for treatment of thrombotic disorders.  相似文献   
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995.
Summary The hepatitis C-virus (HCV) is the main etiologic agent of posttransfusion hepatitis (PTH). Most patients depending on hemodialysis need transfusion of blood before kidney transplantation. Of 272 patients after kidney transplantation, 27 (10%) were found to be anti-HCV-ELISA-positive (HCV-Antibody-ELISA, Ortho Diagnostics). The antibodies could be neutralized by HCV C-100-3 antigen. Eight of 22 patients (36%) who had more than one kidney transplantation were classified anti-HCV positive [30% (8/27) of all anti-HCV positive patients]. The number of transfused blood units ranged from 0 to 99 BU. Receiving more than one kidney graft or the transfusion of more than 5 units of blood increased the risk for HCV infection 3.5 or 4.1 times, respectively, compared with one transplantation or less than 5 units of blood. No significant interactions were seen between these two variables. Of the anti-HCV positive patients, 48% were anti-HBc negative as well as HBs-antigen negative, 52% were anti-HBc positive.Abbreviations A492 absorbance at 492 nm wave-length - ALT alanin-amino-transferase - BU blood units - D dichotomization - HBV Hepatitis B-Virus - HNANB Hepatitis non-A, non-B - OR odds ratio - PTH posttransfusion hepatitis - s/co mean A492/cutoff= ELISA-ratio - TPL transplantation  相似文献   
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999.
Despite the public concern about the controversial use and abuse of marijuana, the scientific community has focused on the therapeutic potentials of cannabinoid compounds and had highlighted the importance of endocannabinoids and their receptors in physiology and disease. Endocannabinoids have been shown to be important mediators in neuroendocrine and psychiatric processes such as food intake, drug reward and energy metabolism. Cannabinoid receptors are expressed by several cell lines in the liver, such as hepatocytes, myofibroblastic cells, endothelial cells and probably cholangiocytes. A perpetuating role in liver damage for the endocannabinoid system has been proposed in several steps of chronic liver disease progression. Being a major cause of death worldwide, chronic liver disease is an important problem. New therapies are needed in order to stop or slow damage progression. This review summarizes the results of experimental studies involving the endocannabinoid system in liver disease and their clinical and therapeutical implications in hepatology.  相似文献   
1000.
Most of the six million Americans with fibromyalgia have at least one associated syndrome which mandates specialized attention in addition to traditional therapeutic approaches. These include localized procedures, regional blocks, antiinflammatory or antimicrobial regimens, attention to non soft tissue sources of psychosocial distress, and classes of medicines not usually prescribed for fibromyalgia. The successful treatment of fibromyalgia-associated syndromes improves the symptoms, quality of life, and prognosis of fibromyalgia.  相似文献   
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