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1.
Ofer Binah Irit Rubinstein Arieh Bomzon Ori S. Better 《Naunyn-Schmiedeberg's archives of pharmacology》1987,335(2):160-165
Summary The effects of sodium salts of various bile acids on the contractile force and the electrophysiological properties of rat ventricular muscle were studied in vitro. Primary, conjugated, and secondary bile acids were studied in a concentration range of 10–9–10–6 mol/l, which corresponds to concentrations found in the plasm of patients with cholestatic jaundice. In general, the bile acid induced a negative inotropic effect which was manifested as a reduction in active tension, maximum rate of tension activation, and maximum rate of tension relaxation. Twitch duration and time to peak tension were unaffected by the bile acids. The negative inotropism was associated with a reduction in ventricular action potential duration. Resting potential, action potential amplitude, and maximum upstroke velocity of phase 0 depolarization were unaffected. Voltage clamp experiments in rat ventricular myocytes demonstrated that sodium taurocholate decreased the slow inward current and slightly increased the outward potassium current. Hence, these effects on the membrane currents are probably responsible for the negative inotropic effect.
Send offprint requests to O. Binah at the above address 相似文献
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Localized osteolysis in stable, non-septic total hip replacement 总被引:6,自引:0,他引:6
M J Jasty W E Floyd A L Schiller S R Goldring W H Harris 《The Journal of bone and joint surgery. American volume》1986,68(6):912-919
We are reporting four cases of extensive, localized bone resorption adjacent to a rigidly anchored, cemented total hip replacement. None of these hips showed evidence of infection on clinical, bacteriological, or pathological evaluation. The tissue from the regions of osteolysis showed sheets of macrophages and foreign-body giant cells invading the femoral cortices. Abundant methylmethacrylate particulate debris was present in the tissues, but polyethylene wear debris was absent. The histological appearance of this tissue resembled that reported about loosened total hip implants with the exception of the synovial-like layer at the cement surface. The cases reported here show that aggressive bone lysis may occur around stable cemented total hip arthroplasties without the presence of sepsis or malignant disease. 相似文献
4.
The 55-kD bactericidal/permeability-increasing protein (BPI) is a neutrophil-derived polypeptide belonging to a family of
lipid and endotoxin binding proteins. BPI is composed of two functionally distinct structural domains: a potently antibacterial
and antiendotoxin ∼ 20-kD aminoterminal half, and an opsonic carboxy-terminal portion. In multiple animal models, a recombinant
amino-terminal fragment of BPI (rBPI21) is nontoxic and protects against gram-negative bacteria and endotoxin. In humans, rBPI21 is also nontoxic and nonimmunogenic and has undergone phase II/III clinical trials with apparent therapeutic benefit. 相似文献
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Ofer Gemer Benjamin Piura Shmuel Segal Ilana Yanai Inbar 《International journal of gynecological pathology》2003,22(4):398-400
Chondroid syringoma of the vulva is an extremely rare tumor. Of the previously reported cases, only one was clinically malignant. The authors describe a case of chondroid syringoma of the right labium majus from which arose a papillary adenocarcinoma. A right inguinal lymph node was replaced with metastatic adenocarcinoma. 相似文献
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Focal glomerulosclerosis in the remnant kidney model--an inflammatory disease mediated by cytokines 总被引:7,自引:0,他引:7
BACKGROUND: The mechanism of progression of established renal disease
remains unclear. While a low protein diet slows this progression, the role
of cytokines in this process has been little investigated. METHODS: We
investigated cytokine expression by Northern blot and immunohistochemistry
in two groups of 5/6 nephrectomized rats (5/6 Nx) fed a normal (24%) or low
(6%) protein diet and compared them with sham operated controls. RESULTS:
The rats on 6% protein diet had significantly less focal glomerulosclerosis
(FGS) (17.4 +/- 4.4 vs 27.4 +/- 8.8%, P < 0.05) and global sclerosis
(GGS) after 7 weeks (0.4 +/- 0.8 vs 3.5 +/- 2.1% of glomeruli P < 0.05).
Both experimental groups showed three times control levels of MCP-I
expression after 2 weeks. However in the 5/6 Nx 6% protein group the
expression decreased at 4 weeks (1.5 times controls) and reached control
levels after 7 weeks. In contrast, the 5/6 Nx 24% protein group exhibited a
further marked increase after 4 weeks (5.6 times controls) and was still
two-fold higher after 7 weeks. TGF-beta expression was modestly but
consistently increased at all time points (120-160% of controls), with no
difference between the two study groups. Neither IL-1 beta or TNF-alpha was
detectable at any time. Immunohistochemistry demonstrated TGF-beta
intracellularly in distal tubular cells in both experimental and control
animals, while MCP-1 protein was found in the area of FGS and in the apical
pole of distal tubular cells in both experimental groups. Glomerular and
interstitial ED1 positive cells were significantly increased after four
weeks in the 5/6 Nx 24% protein group (P < 0.05). CONCLUSIONS: A
'mechanical' injury to the kidney clearly results in an inflammatory
response associated with the upregulation of MCP-1. A low protein diet
modulates the expression of MCP-1 and improves the morphological sequelae
seen after renal ablation.
相似文献
10.
Amr E Abbas F David Fortuin Bhavesh Patel Carlos A Moreno Nelson B Schiller Steven J Lester 《Journal of the American Society of Echocardiography》2004,17(8):834-838
BACKGROUND: Systemic vascular resistance (SVR) is an integral therapeutic component of patients with heart failure and shock. We hypothesized that the ratio of the peak mitral regurgitant velocity (MRV) (m/s) to left ventricular outflow time-velocity integral (TVI(LVOT)) (cm) by Doppler would provide a noninvasive correlate of SVR. METHODS: SVR was correlated to MRV/TVI(LVOT) in 33 patients undergoing right heart catheterization. Receiver operating characteristic curves were generated to determine the best-balanced sensitivity and specificity to identify SVR > 14 Wood units (WU) and <10 WU. RESULTS: MRV/TVI(LVOT) correlated well with SVR (r = 0.842, 95% confidence interval 0.7-0.92, P <.001, Y = 0.459 + 49.397*X). By receiver operating characteristics, MRV/TVI(LVOT) > 0.27 had a 70% sensitivity and a 77% specificity to identify SVR > 14 WU. MRV/TVI(LVOT) < 0.2 had a 92% sensitivity and a 88% specificity to identify SVR < 10 WU. CONCLUSION: Doppler echocardiography provides a reliable noninvasive assessment of SVR. 相似文献