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991.
992.
AIDS and Behavior - In this mixed-methods study, we examine the relationship between provider communication and patient health literacy on HIV continuum of care outcomes among women living with HIV...  相似文献   
993.
Journal of Interventional Cardiac Electrophysiology - Ablation index (AI) is a radiofrequency lesion quality marker. The AI value that allows effective and safe pulmonary vein isolation (PVI) is...  相似文献   
994.
Heart Failure Reviews - Methamphetamine abuse is a global epidemic associated with a wide-ranging array of adverse effects on the cardiovascular system including dilated cardiomyopathy, malignant...  相似文献   
995.
Cytogenetic abnormalities of chromosome 13 (CA 13) and those detected by fluorescence in situ hybridization (FISH 13) have both been associated with poor prognosis in multiple myeloma (MM) patients. The prognostic implications of CA, FISH 13 and other standard laboratory parameters were examined in the first 231 patients enrolled in Total Therapy II, an intensive cytotoxic chemotherapy programme with tandem autotransplants. Three-year projections of event-free survival (EFS) and overall survival (OS) were 71% and 77% respectively. CA 13 was detected in 14% and significantly correlated with FISH 13 (present in 51%), tumour burden, proliferative activity and lactic dehydrogenase (LDH). Both EFS and OS were significantly shorter in patients with CA 13, FISH 13, LDH >or= 190 U/l, beta2 microglobulin >or= 4 mg/l and C reactive protein >or= 4.0 mg/l; other CA was an additional risk factor for OS. Two-thirds of CA 13 patients were identified by FISH 13 and plasma-cell-labelling index (PCLI) >or= 0.4%; however, PCLI failed to identify additional risk groups in FISH subsets. Although present in considerably fewer patients, CA 13 imparted more rapid relapse (61% at 3 years) and death (43% at 3 years) than FISH 13 (38% and 35%; P = 0.02 and 0.1 respectively) and should be part of the initial work-up of patients with MM.  相似文献   
996.
The binding of 125I-labelled bovine TSH to a human thyroid cell line (SGHTL-34) has been studied. Binding to hormonally responsive cells was time dependent, specific and reversible. Scatchard analysis of the binding data indicated the presence of a single binding site with high affinity (intrinsic dissociation constant (Kd) = 0.25 +/- 0.08 nmol/l; mean +/- S.E.M.; n = 4) and low capacity (maximum binding (Bmax) = 104 +/- 29 fmol/mg protein; mean +/- S.E.M.; n = 4). Hill plots confirmed the presence of a single site. Kinetic data demonstrated close agreement between the Kd and Bmax obtained from the competition data (Kd = 0.23 +/- 0.35 nmol/l; Bmax = 161 +/- 83 fmol/mg protein; n = 6).  相似文献   
997.
A high prevalence of a common mutation in the Hfe gene (C282Y) has recently been reported in patients with the factor V Leiden mutation and a history of thrombosis. The aim of this study was to estimate the relative risk of venous thromboembolism in a large case-control study. 56/481 patients (11.6%) and 57/497 controls (11.5%) were heterozygous for the C282Y allele giving an odds ratio of 1.02 (95%CI 0.69-1.51). 12/81 patients with the factor V Leiden mutation were heterozygous for the C282Y allele compared to 1/13 controls, odds ratio 2.09 (95%CI 0.25-17.6). An analysis of a further group of patients and controls selected for the factor V Leiden mutation did not indicate a higher prevalence of the C282Y allele in symptomatic patients, odds ratio 0.17 (95%CI 0.34-0.81). This study does not support the hypothesis that the C282Y allele is an additional risk factor for venous thrombosis in patients with the factor V Leiden mutation.  相似文献   
998.
BACKGROUND. A number of parameters reflecting the effects of idiopathic dilated cardiomyopathy (IDC) on the structure and function of myosin from the human myocardium were analyzed. METHODS AND RESULTS. The content of the regulatory light chain, LC2, was reduced in myopathic heart myosin in contrast to the controls in which it was present in stoichiometric amounts relative to the essential light chain, LC1. In IDC hearts, the absence or significant reduction in amount of LC2 was related to the presence of an active protease, which was isolated and purified about 130-fold. The protease exhibited a significant degree of specificity: It cleaved LC2 almost totally (but not the heavy chains) in human control heart myosin but only partially cleaved LC2 in canine heart or in rabbit skeletal muscle myosins. The protease was present at a very low level or was inactive in control heart tissue. When the LC1/LC2 molar ratio was calculated, it was found to be 1:1.0 in control heart myosin and remained constant in various samples analyzed, whereas in myopathic myosin from different individuals, this ratio varied from 1:0.1 to 1:0.69. The rates of ATP binding to control and myopathic myosins were similar, whereas the Vm of actin-activated ATPase of myopathic myosin was about 25% less than that of the control. However, ATP binding and its hydrolysis by control S1, i.e., the myosin head, were faster by a factor of 2 than that of the myopathic S1. In addition, control myosin synthetic thick filament length as well as turbidity in solution, measured by light scattering, were twice as large as those of the myopathic heart myosin. These effects induced by myopathy in both filament assembly and turbidity were reversed upon reassociation of IDC myosin with LC2. CONCLUSIONS. The changes in myosin structure and function were linked to a protease-mediated cleavage of LC2 in myosin; a possible role for the protease in the degenerative effects of idiopathic dilated cardiomyopathy is thus defined.  相似文献   
999.
BACKGROUND--Progressive pulmonary vascular disease in surgically unrepaired transposition of the great arteries with or without ventricular septal defect had been frequently described in the past. Occurrence of progressive pulmonary vascular disease has been reported even after atrial switch procedure done at three months of age. With the advent of neonatal surgical repair, this problem is virtually non-existent. There is a small subgroup of infants with transposition of the great arteries who show pulmonary vascular disease in the neonatal period that can adversely affect the surgical outcome. The clinico-pathological correlation in this group of patients was studied. OBSERVATIONS--Three patients, with transposition of the great arteries and intact ventricular septum, who showed histological evidence of pulmonary vascular disease in the neonatal period or early infancy are described. Two of these patients, continued to have poor systemic oxygenation despite adequate atrial communication. One patient had a close ductus arteriosus within the first two hours of birth while on prostaglandin E1 infusion. CONCLUSIONS--In the absence of left ventricular outflow tract obstruction, a poor response to atrial septostomy suggests pulmonary hypertension and pulmonary vascular disease. Antenatal constriction of the ductus arteriosus may contribute to such changes in pulmonary vasculature.  相似文献   
1000.
Total anomalous pulmonary venous drainage in infancy.   总被引:3,自引:1,他引:3       下载免费PDF全文
Between May 1971 and December 1975, 39 infants had operations for correction of total anomalous pulmonary venous drainage. Fourteen of the 39 patients were under 1 month of age at the time of operation. Twenty-four patients had supracardiac, 7 intracardiac, and 6 infracardiac total anomalous pulmonary venous drainage, and 2 had a mixed type. The overall hospital mortality was 36 per cent. There have been no late deaths. The improvement in survival rate in this series is attributed to: (1) earlier recognition and prompt referral, (2) an aggressive approach to diagnosis involving complete cardiac catheterisation and angiocardiography, (3) vigorous preoperative care, (4) early complete correction including construction of a large anastomosis and enlargement of the left atrium when indicated, and (5) intensive postoperative management paying particular attention to fluid balance and treatment of pulmonary complications. Operative mortality was highest in patients with total anomalous pulmonary venous drainage directly to the superior vena cava, and in those with infradiaphragmatic drainage of whom all had pulmonary venous obstruction. Mortality was not closely related to age, body weight, or severity of pulmonary hypertension.  相似文献   
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