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831.
Cost-effectiveness of Veterans Administration hospital-based home care. A randomized clinical trial 总被引:6,自引:0,他引:6
J E Cummings S L Hughes F M Weaver L M Manheim K J Conrad K Nash B Braun J Adelman 《Archives of internal medicine》1990,150(6):1274-1280
A randomized design was used to examine the cost-effectiveness of a Veterans Administration hospital-based home care program that case managed inpatient and outpatient care. Patients (N = 419) with two or more functional impairments or a terminal illness were randomized to hospital-based home care (n = 211) or customary care (n = 208). Functional status, satisfaction with care, and morale were measured at baseline and at 1 and 6 months after discharge from the hospital; health care utilization was tracked for 6 months. Findings included significantly higher (0.1 on a three-point scale) patient and caregiver satisfaction with care at 1 month and lower Veterans Administration and private sector hospital costs ($3000 vs $4245) for the experimental group. Net per person health care costs were also 13% lower in the experimental group. We conclude that this model of hospital-based home care is cost-effective and that its expansion to cover these two patient groups throughout the Veterans Administration system can improve patient care at no additional cost. 相似文献
832.
A randomized controlled trial of recombinant interferon-alpha in chronic hepatitis C in hemophiliacs 总被引:1,自引:0,他引:1
Chronic liver disease associated with hepatitis C virus (HCV) is an important cause of morbidity and mortality in hemophilia. We have used recombinant interferon alpha-2b (IFN alpha-2b) in a randomized controlled liver biopsy trial to treat hemophiliacs with chronic hepatitis. Eighteen patients entered the study, 16 of whom were subsequently shown to have antibodies to the HCV. All underwent liver biopsy at entry and were randomized to either treatment with self-administered IFN alpha-2b, 3 million units subcutaneously thrice weekly (n = 10) or no treatment (control group) (n = 8). Nine subjects had chronic active hepatitis, seven had chronic persistent hepatitis, and two had cirrhosis. Twelve months after entry into the study 17 patients underwent a second liver biopsy. All biopsies were coded, assessed, and scored according to the histologic severity of the liver disease. Ten patients were administered IFN for 1 year, and in four patients normalization of alanine aminotransferase (ALT) occurred compared with none in the untreated group. After the second liver biopsy, six of the eight initial no-treatment patients were treated with interferon 3 million units thrice weekly for 6 months, and normalization of ALT was seen in five patients. Biochemical relapse within 4 months of stopping IFN occurred in one of four patients treated for 1 year and in four of five patients treated for 6 months. IFN treatment was well tolerated. Although the histologic scores of the two groups were similar at entry into the study, after 12 months the biopsy appearances in the treated group were significantly improved compared with the controls (P less than .01). Histologic improvement was noted in the three interferon-treated human immunodeficiency virus antibody-positive patients and also in other patients who had no biochemical response. We conclude that low-dose recombinant IFN alpha is effective in normalizing transaminases and improving the histologic appearances in at least 50% of hemophiliacs with chronic hepatitis C. 相似文献
833.
834.
The hypothalamic-pituitary axis of streptozotocin-induced diabetic female rats is not normalized by estradiol replacement 总被引:1,自引:0,他引:1
Studies in diabetic rats have found abnormalities at the hypothalamic, pituitary, and/or ovarian level but have not controlled for changes in estrogen levels induced by diabetes. The purpose of this investigation was to study the effect of diabetes on the hypothalamic-pituitary axis in ovariectomized rats treated with estradiol (E2). Ovariectomized 60 day old female rats were assigned to control (C, n = 42), diabetic (D, n = 47) or insulin-treated diabetic (DI, n = 16) groups. Diabetes was induced with an injection of streptozotocin in the D and DI groups. In the C, D, and DI groups, estrogen was replaced by implanting blank, 5 micrograms or 20 micrograms E2 pellets sc. Pituitary LH responsiveness to GnRH was assessed in C and D animals. Anterior hypothalamic and midhypothalamic concentrations of proGnRH and GnRH, pituitary LH and FSH and serum levels of LH, and E2 were measured by RIA. Anterior hypothalamic proGnRH concentrations were decreased in diabetic rats treated with 5 micrograms E2 compared to 5 micrograms E2 control animals (P less than 0.05). Midhypothalamic GnRH concentrations were also reduced in D vs. C animals despite comparable estrogen therapy (P less than 0.004). GnRH-stimulated LH levels were greater in E2-treated diabetic females than in similarly treated control rats (P less than 0.001). D and DI animals were more sensitive than controls to the inhibitory effect of estrogen on basal LH levels. Pituitary LH and FSH content was lower in 20 micrograms E2-replaced animals but was not influenced by the diabetic state. These data demonstrate a diabetes-induced decrease in hypothalamic proGnRH and GnRH concentration which is not corrected with E2 replacement. The hyper-responsiveness of the diabetic rat pituitary to GnRH also suggests a chronic lack of GnRH stimulation from the hypothalamus but a continued ability of the pituitary to respond to GnRH. 相似文献
835.
Effects of ovariectomy on GnRH mRNA, proGnRH and GnRH levels in the preoptic hypothalamus of the female rat 总被引:1,自引:0,他引:1
M J Kelly J Garrett M A Bosch C E Roselli J Douglass J P Adelman O K Ronnekleiv 《Neuroendocrinology》1989,49(1):88-97
Experiments were carried out to investigate the effects of ovariectomy on gonadotropin-releasing hormone (GnRH) messenger RNA (mRNA), proGnRH and GnRH peptide levels in the hypothalamus of female rats. Intact proestrous female rats and female rats, which had been ovariectomized for 2 weeks, were sacrificed at 9.00 h and the preoptic area (POA) and basal hypothalamus (BH) were dissected out and frozen on dry ice. One group of tissues from proestrous control and ovariectomized females were extracted in acetic acid, centrifuged at 13,000 g and the supernatant purified on a C18 column. The purified extract was then radioimmunoassayed for proGnRH, using a specific antiserum to rat proGnRH (ARK-2), and for GnRH using the E1-14 antiserum. Total cellular RNA was isolated from another group of tissues and prepared as Northern blots. Hybridization with 32P-labeled GnRH cRNA was used to detect GnRH mRNA. A third group of proestrous and ovariectomized female rats were perfused, and 50 microns vibratome sections were cut. These were immunostained with proGnRH or GnRH antiserum, followed by in situ hybridization with 35S-labeled GnRH cRNA to detect GnRH mRNA. Based on the histochemical staining, mRNA was colocalized to the cell soma of neurons containing proGnRH and GnRH throughout the POA and BH. Based on the radioimmunoassay, proGnRH levels were 2 times higher in the POA versus the BH, but GnRH levels were 6-7 times higher in the BH. Ovariectomy significantly decreased proGnRH levels in both the POA and BH, while GnRH decreased in the BH. In contrast, quantitative Northern blot analysis demonstrated that ovariectomy had no effect on mRNA levels in the POA and BH. These data indicate that the effects of ovariectomy on proGnRH and GnRH levels are a result of altered translation, posttranslational processing and/or secretion of GnRH. 相似文献
836.
von Willebrand factor is present on the surface of platelets stimulated in plasma by ADP 总被引:2,自引:0,他引:2
von Willebrand factor (vWf) can bind to glycoprotein (GP) IIb/IIIa on activated platelets. The significance of this interaction is unclear, however, because it has not been possible to detect vWf binding to GPIIb/IIIa on platelets stimulated in plasma. We have developed an indirect, flow cytometry assay that uses fluorescein-labeled antibodies to detect vWf and fibrinogen on platelets. Using this assay, we found vWf on the surface of platelets stimulated in plasma by ADP. The number of platelets that bound vWf increased in proportion to ADP concentration and incubation time. Washed platelets in a protein-free buffer activated by 1 mumol/L calcium ionophore A23187 or 10 mumol/L ADP also bound vWf, suggesting that we were detecting surface binding of alpha-granule-derived vWf. Monoclonal antibodies against the vWf binding site on GPIb (6D1) and the vWf and fibrinogen binding sites on GPIIb/IIIa (LJP5 and LJ-CP8, respectively) were used to characterize the mechanism of vWf binding to stimulated platelets. Ristocetin- induced binding of vWf was inhibited by 6D1, and ADP-induced binding of fibrinogen was inhibited by LJ-CP8. None of these antibodies inhibited ADP-induced vWf binding. Aspirin and prostaglandin E1 also inhibited ADP-induced binding of vWf in platelet-rich plasma. During platelet activation in plasma, vWf derived from alpha-granules becomes bound to the platelet surface possibly being transferred already associated with a binding site. 相似文献
837.
838.
We have studied the effect of streptokinase on platelets in platelet- rich plasma (PRP) and of plasmin on washed platelets. By three and one- half minutes after the addition of 50,000 IU/mL streptokinase to PRP, the maximum rate of ristocetin-induced platelet agglutination declined 40%, and by 60 minutes, it declined 70%. During the same time interval, the thrombin time increased from 20 seconds to over 120 seconds. At a concentration as low as 50 IU/mL, streptokinase reduced the maximum rate of ristocetin-induced platelet agglutination by 50% and prolonged the thrombin time to 1.5 times control value. Streptokinase added to PRP also caused inhibition of platelet aggregation following stimulation by 2.9 mumol/L adenosine diphosphate, 0.25 U/mL thrombin, and 0.025 mg/mL collagen. Plasmin, 0.05 to 1.0 CU/mL, reduced ristocetin-mediated agglutination of washed platelets in the presence of von Willebrand factor (vWF) from 66% of control to 2% of control, following a one-hour incubation. Autoradiograms produced following sodium dodecyl-polyacrylamide gel electrophoresis (SDS-PAGE) of plasmin- treated 125I-surface-labeled platelets demonstrated progressive loss of a protein with a molecular weight (mol wt) of 180,000; simultaneously, a protein with mol wt 135,000 appeared on autoradiograms produced following SDS-PAGE of the surrounding platelet medium. These proteins are similar in molecular weight to glycoprotein (gp) Ib, a platelet surface receptor for vWF, and glycocalicin, a proteolytic fragment of gpIb. By use of an enzyme-linked immunosorbent assay (ELISA) based immunoinhibition assay for glycocalicin, we were able to demonstrate that plasmin treatment of washed platelets released a glycocalicin- related antigen into the surrounding medium and that appearance of this material corresponding to loss of vWF-dependent, ristocetin-induced agglutination. 相似文献
839.
Homology of the rat basophilic leukemia cell and the rat mucosal mast cell. 总被引:17,自引:5,他引:17 下载免费PDF全文
D C Seldin S Adelman K F Austen R L Stevens A Hein J P Caulfield R G Woodbury 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(11):3871-3875
Secretory granules of the rat basophilic leukemia (RBL-1) cell, a chemically generated tumor cell line maintained in tissue culture, were shown to stain with alcian blue but not with safranin counterstain and to have sparse, small, electron-dense granules. A Mr 25,000 protein was the major [3H]diisopropyl fluorophosphate-binding protein in extracts of RBL-1 cells. Double-immunodiffusion analysis of extracts revealed immunoreactivity for rat mast cell protease (RMCP)-II, a Mr 25,000 neutral protease present in the secretory granules of rat mucosal mast cells and cultured rat bone marrow-derived mast cells, but no immunoreactivity for RMCP-I, the predominant neutral protease of rat connective tissue mast cells. By radial immunodiffusion, there was 66.8 ng of RMCP-II per 10(6) cells. Whereas rat connective tissue mast cells stain with alcian blue and safranin and contain heparin proteoglycan, rat mucosal and rat bone marrow-derived mast cells stain with alcian blue only and contain a non-heparin proteoglycan and lesser amounts of histamine. Proliferation of rat mucosal mast cells in vivo and rat bone marrow-derived mast cells in vitro requires T-cell factors, whereas no comparable requirement has been observed for connective tissue mast cells. The transformed RBL-1 tumor cells, whose growth is independent of factors other than those present in standard tissue culture medium, has previously been shown to contain predominantly chondroitin sulfate di-B proteoglycans and low amounts of histamine. The similar histology and secretory granule biochemistry of the rat mucosal mast cells, rat culture-derived mast cell, and RBL-1 cell suggest that they comprise a single mast cell subclass distinct from the rat connective tissue mast cell. 相似文献
840.