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41.
Using the Gomco circumcision clamp and sealing the wound with tissue adhesive results in a minimally invasive circumcision suitable for all age groups beyond the neonatal period. It is easy to perform and can be performed by generalists with local anaesthetic and standard instruments. 相似文献
42.
Our objectives were to translate the Quality of Life Scale (QOLS) into German and to evaluate its reliability and validity for the use in patients with fibromyalgia (FMS). Together with German versions of the Fibromyalgia Impact Questionnaire (FIQ), the SF-36, a tender point count (TPC) and other questionnaires, we administered the QOLS to 146 patients with FMS. Patients were asked about the severity of pain today (VAS) and the duration of symptoms. Test-retest reliability was assessed using Spearman's correlations. Internal consistency was evaluated with Cronbach's alpha. Construct validity of the QOLS was evaluated by correlating the QOLS with the FIQ, the SF-36, the Beck Depression Inventory (BDI), and the Symptom Checklist (SCL-90-R) as well as with the pain variables. An exploratory factor analysis (EFA) was also conducted. Mean age was 53.1?years. Means were for pain today 6.8 and for duration of symptoms 11.8?years. Test-retest reliability for the total QOLS was rho?=?.91. Internal consistency was α?=?.90. Low-to-moderate correlations were obtained between the QOLS and the total FIQ (rho?=?-.42**), the SF-36 (e.g. physical functioning rho?=?.37**; mental health rho?=?.56**) as well as the pain variables (VAS rho?=?-.11?ns; TPC rho?=?-.20*). Psychological variables were moderately to substantially correlated with the QOLS (e.g. BDI rho?=?-.61**). An EFA suggested a three-factor solution. The QOLS-G is a reliable and valid instrument for measuring quality of life in German patients with FMS. 相似文献
43.
44.
Cavitating metastatic lesions in the lungs as a manifestation of metastatic transitional cell carcinoma (TCC) is rare. We herein present a case of multiple cavitary pulmonary metastases secondary to TCCF of the left ureter and bladder. 相似文献
45.
Primitive hematopoietic stem cells differentiate into committed progenitors that are thought to selectively express hematopoietic growth factor receptor(s), thereby acquiring hematopoietic growth factor responsiveness. To assess whether hematopoietic stem cells express hematopoietic growth factor receptors, the progenitor activity of bone marrow (BM) fractions, isolated by expression of receptors for macrophage/monocyte colony-stimulating factor (M-CSF), were examined. Recovery of day-12 spleen colony-forming units (CFU-S) is diminished in both M-CSF receptor-positive (M-CSFR+) and M-CSFR- fractions, indicating antibody inhibition of day-12 CFU-S. Incubation of BM cells with antibody without fractionation inhibits 50% to 60% of day-12 CFU- S. This inhibition is specific (control antibodies have no effect) and reversible by removal of bound antibody at low pH. Incubating BM cells with control or antireceptor antibody does not affect day-8 CFU-S, which are predominantly erythroid. Treating sublethally irradiated mice with antibody inhibits endogenous day-12 CFU-S. These results indicate that some early progenitors express M-CSFRs, and blocking M-CSFRs inhibits the ability of these progenitors to form colonies, possibly because of inactivation caused by prolonged receptor blockade. 相似文献
46.
Our study was designed to determine whether the calcium channel antagonists verapamil, diltiazem, and nifedipine and the nitrate vasodilator sodium nitroprusside modulate carotid sinus (CS) baroreflex control of mean arterial pressure (MAP) and heart rate (HR). Pentobarbital-anesthetized, vagotomized dogs were surgically prepared for reversible vascular isolation of the CS regions. Open-loop performance of the CS baroreflex was determined under control conditions and after intravenous infusion of each agent for 20 minutes at four rates (nitroprusside: 0.3-10 micrograms/kg/min; verapamil and diltiazem: 1-30 micrograms/kg/min; nifedipine: 0.1-3 micrograms/kg/min). With the CS baroreflex loop closed, each vasodilator decreased MAP from control (nitroprusside: 127 +/- 3 to 69 +/- 5 mm Hg; verapamil: 137 +/- 7 to 86 +/- 5 mm Hg; diltiazem: 137 +/- 9 to 100 +/- 5 mm Hg; nifedipine: 140 +/- 6 to 109 +/- 7 mm Hg). Each compound also caused a dose-dependent downward shift in the open-loop CSP-MAP relations. The higher doses of each vasodilator also depressed the total range of control of MAP (i.e., maximum MAP minus minimum MAP) by the baroreflex and significantly attenuated the peak open-loop MAP/CSP gains (nitroprusside: 1.21 +/- 0.19 to 0.56 +/- 0.12; verapamil: 1.36 +/- 0.16 to 0.64 +/- 0.10; diltiazem: 1.52 +/- 0.34 to 0.89 +/- 0.11; nifedipine: 1.35 +/- 0.20 to 0.83 +/- 0.14) but did not alter the CSP at which the peak gain was manifest. Only verapamil and diltiazem significantly shifted downward the CSP-HR relations, whereas none of the drugs affected the total range of baroreflex control of HR (i.e., maximum HR minus minimum HR) or the peak open-loop HR/CSP gains. Our results suggest that 1) it is unlikely that calcium channel antagonists act directly on the baroreceptors or the neural components of the baroreflex loop (i.e., afferent, central and efferent nerves) because they impair CS baroreflex control of MAP but not HR and 2) the impairment of MAP control is predominantly due to a nonspecific blunting of adrenergic vasoconstriction. 相似文献
47.
48.
E. Tim O'Brien III Michael R. Falvo Daniel Millard Brian Eastwood Russell M. Taylor II Richard Superfine 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(49):19438-19443
Fibrin polymerizes into the fibrous network that is the major structural component of blood clots and thrombi. We demonstrate that fibrin from three different species can also spontaneously polymerize into extensive, molecularly thin, 2D sheets. Sheet assembly occurs in physiologic buffers on both hydrophobic and hydrophilic surfaces, but is routinely observed only when polymerized using very low concentrations of fibrinogen and thrombin. Sheets may have been missed in previous studies because they may be very short-lived at higher concentrations of fibrinogen and thrombin, and their thinness makes them very difficult to detect. We were able to distinguish fluorescently labeled fibrin sheets by polymerizing fibrin onto micro-patterned structured surfaces that suspended polymers 10 μm above and parallel to the cover-glass surface. We used a combined fluorescence/atomic force microscope system to determine that sheets were ≈5 nm thick, flat, elastic and mechanically continuous. Video microscopy of assembling sheets showed that they could polymerize across 25-μm channels at hundreds of μm2/sec (≈1013 subunits/s·M), an apparent rate constant many times greater than those of other protein polymers. Structural transitions from sheets to fibers were observed by fluorescence, transmission, and scanning electron microscopy. Sheets appeared to fold and roll up into larger fibers, and also to develop oval holes to form fiber networks that were “pre-attached” to the substrate and other fibers. We propose a model of fiber formation from sheets and compare it with current models of end-wise polymerization from protofibrils. Sheets could be an unanticipated factor in clot formation and adhesion in vivo, and are a unique material in their own right. 相似文献
49.
Regional myocadial blood flow and cardiac mechanics in dog hearts with CO2 laser-induced intramyocardial revascularization 总被引:4,自引:0,他引:4
R. I. Hardy MD PhD F. W. James R. W. Millard S. Kaplan 《Basic research in cardiology》1990,85(2):179-197
Summary Laser-induced intramyocardial revascularization (LIR) has been used to promote direct communications between blood within the ventricular cavity and that of the existing myocardial vasculature in an attempt to increase perfusion in patients with ischemic heart discase. This study was conducted to measure the effects of LIR channels on regional myocardial flood flow (microspheres), cardiac mechanics (sonomicrometers), and myocardial tissue pressures in 18 dogs. Under baseline hemodynamic conditions (mean HR=165.2±11.4 bpm, LVP=123.6±22.9/4.0±1.8 mmHg, AoP=112.8±27.1/77.0±22.5 mmHg), myocardial blood flow in laser-treated tissue (mean =1.11±.10 cc/min/gm before laser; .71±.19 cc/min/gm after laser) was reduced as compared to blood flow in control tissue (mean=1.12±.15 cc/min/gm before laser; 1.25±.22 cc/min/gm after laser). Regional myocardial systolic shortening (11.32%±3.82% before laser; 7.49%±2.86% after laser) was decreased by 33%. During simultaneous reversible ligation of the LAD and LCCA for 2 min, when intramyocardial channels represented the only tissue access for the injected microspheres, blood flow in laser-treated tissue was not increased above that of the control non-lasered tissue. However, regional blood flow was greater in laser-treated ischemic tissue (mean=.61±.12 cc/min/gm) than in untreated ischemic areas (mean=.04±.03 cc/min/gm) when left ventricular pressure (LVP) was acutely elevated (mean SLVP=207.0±16.1 mmHg). Using these measurements, a model is proposed to predict regional systolic pressure gradients between the left ventricular cavity and coronary intramyocardial vasculature required to permit restoration of blood flow to ischemic myocardium. We conclude that improved perfusion via laser-induced intramyocardial channels does not occur in otherwise normal myocardium exposed to acute coronary ligation and only small improvements in perfusion are noted when LVP is significantly elevated. Consideration of further clinical application of this approach is seriously cautioned awaiting additional experimental studies.This study was supported by U.S. Public Health Service Grant R01 HL32897-01 from the National Heart, Lung, and Blood Institute, by grants in aid from the American Heart Association, and by the Fulbright-Hays Scholarship Grant. 相似文献
50.
Rapid prenatal diagnosis of beta thalassemia using DNA amplification and nonradioactive probes 总被引:3,自引:0,他引:3
We used in vitro DNA amplification by the polymerase chain reaction and nonradioactive probes for prenatal diagnosis of beta thalassemia in Chinese from the Guangdong province. Exact molecular diagnoses were made in all 20 fetuses studied over a 6-month period. We conclude that this method of prenatal diagnosis for beta thalassemia is a viable approach in many parts of the world where this disease is common. 相似文献