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91.
92.
In an attempt to determine the risks for and kinds of dementia most prevalent among the African American population, the Alzheimer's Disease Research Center at the University of Pittsburgh developed a community satellite program specifically targeting the African American and historically medically underserved communities in Allegheny County, PA. The primary mission of the Alzheimer Outreach Center (AOC) was to increase the awareness of AD among the targeted population. The number of nonwhite patients participating in the studies at ADRC increased from 2 to 16% in the first year of the program. In May 1995, the AOC became a permanent ADRC program.  相似文献   
93.
There has been much debate in recent years about the implementation of community care policies for people with learning difficulties. The debate has centred on the following points: what the real costs and benefits of community care are, and to whom; what a community care service should look like; who should provide the service and how should it best be funded. This paper presents the results of a study comparing the costs and outcomes to clients of a variety of residential services for people with learning difficulties. The services evaluated range from traditional hospital services to small community based homes, run on 'ordinary life' principles. The purpose of the study was to collect information to aid policy makers and service providers in deciding how best to implement the community care initiative.  相似文献   
94.
95.
Fasting plasma proinsulin, insulin and glucose concentrations were measured in ten women with mild gestational diabetes and ten controls matched for race, age (32 +/- 6 vs 31 +/- 6 years), body mass index (28 +/- 8 vs 27 +/- 6) and gestational week (24 +/- 4 vs 25 +/- 4 weeks). There was no significant difference in fasting plasma glucose between these gestational diabetics and their controls (median 4.7, range 3.7-6.0 mmol/l vs 4.5, range 3.4-5.3 mmol/l). The fasting proinsulin levels were significantly higher in the gestational diabetics compared with the controls (median 12.2, range less than 4-14.8 pmol/l vs 5.8, range less than 4-12.8 pmol/l, P less than or equal to 0.02, Wilcoxon Summed Rank Test), while the calculated intact insulin levels (immunoreactive insulin minus proinsulin) were significantly lower (median 14.5, range 6.3-81.8 pmol/l vs 51.6, range 11.7-312 pmol/l, P less than or equal to 0.01). The ratio of proinsulin to calculated intact insulin was significantly higher in the gestational diabetics than the controls (median 0.66, range 0.16-2.04 vs 0.12, range 0.03-0.62), P less than or equal to 0.01). These results demonstrate that gestational diabetics, with normal fasting plasma glucose values, have abnormalities in pancreatic beta-cell secretion, which are likely to be important both in the aetiology of gestational diabetes and non-insulin dependent diabetes.  相似文献   
96.
This paper presents the results obtained from 87 questionnaires completed by dietitians about the dietary management of gall-biadder disease. Of the patients referred to the dietitians, 86% were referred by surgeons. Of the dietitians that responded 77% thought that there was a role for low fat diets in the management of these patients; 92% would advise a low fat diet to help avoid pain, and 11% would advise a low fat diet to patients with gall-bladder disease who did not have pain, steatorrhoea or obesity.
The paper reviews the available evidence concerning the effect of dietary fat on the gall-bladder; it is concluded that, at present, there is little data to support the therapeutic use of a low fat diet for individuals with gall-stones.  相似文献   
97.
Chinese hamster V79 fibroblasts were irradiated in the gas explosion apparatus and the chemical repair rates of the oxygen-dependent free radical precursors of DNA double-strand breaks (dsb) and lethal lesions measured using filter elution (pH 9.6) and a clonogenic assay. Depletion of cellular GSH levels, from 4.16 fmol/cell to 0.05 fmol/cell, by treatment with buthionine sulphoximine (50 mumol dm-3; 18 h), led to sensitization as regards DNA dsb induction and cell killing. This was evident at all time settings but was particularly pronounced when the oxygen shot was given 1 ms after the irradiation pulse. A detailed analysis of the chemical repair kinetics showed that depletion of GSH led to a reduction in the first-order rate constant for dsb precursors from 385 s-1 to 144 s-1, and for lethal lesion precursors from 533 s-1 to 165 s-1. This is generally consistent with the role of GSH in the repair-fixation model of radiation damage at the critical DNA lesions. However, the reduction in chemical repair rate was not proportional to the severe thiol depletion (down to approximately 1% for GSH) and a residual repair capacity remained (approximately 30%). This was found not to be due to compartmentalization of residual GSH in the nucleus, as the repair rate for dsb precursors in isolated nuclei, washed virtually free of GSH, was identical to that found in GSH-depleted cells (144 s-1), also the OER remained substantially above unity. This suggests that other reducing agents may have a role to play in the chemical repair of oxygen-dependent damage. One possible candidate is the significant level of protein sulphydryls present in isolated nuclei.  相似文献   
98.
Summary Partial anomalous pulmonary venous connections (PAPVCs) are rare in association with an intact atrial septum. However, the diagnosis should be considered in patients with otherwise unexplained findings of left-to-right shunt and right heart enlargement. An unusual variant is presented, which we considered unsuitable for operative repair, based on findings at catheterization. Developmental, hemodynamic, and surgical considerations are discussed.  相似文献   
99.
Administration of high-dose chemotherapy to patients with myeloma, followed by rescue with autologous bone marrow transplantation (ABMT), sometimes induces complete disease remission but relapse is usual. We have attempted to reduce the risk of relapse by selective in vitro removal of myeloma cells from the autologous graft. A combination of the (gal-galNac)-binding lectin peanut agglutinin (PNA), which binds all plasma cells, and the pan-B monoclonal antibody CD19 was assessed for purging marrow of myeloma cells and their putative precursors using a magnetic bead method. Preliminary experiments performed on peripheral blood mononuclear cells spiked with fluorescent-labeled PNA+ Kirk tumor cells showed that a magnetic bead: target cell ratio of 40:1 resulted in a greater than 3-log reduction in PNA+ cells. This technique was then applied to 17 samples of myeloma bone marrow and to 18 samples of normal bone marrow spiked with PNA+ Kirk cells and CD19+ hairy cell leukemia cells. In each case all detectable plasma cells and CD19+ lymphocytes were effectively removed, and normal hemopoietic progenitor cell recovery was greater than 55%. This purging system deserves further study as a means of reducing relapse rates in myeloma patients treated by a combination of high-dose chemotherapy and ABMT.  相似文献   
100.
1 The ability of iloprost (ZK36374) to protect hamster isolated hepatocytes from the toxic effects of paracetamol and its reactive metabolite N-acetyl-p-benzoquinoneimine (NABQI) was investigated. The cytoprotection provided by iloprost was compared with that of N-acetyl-L-cysteine. 2 Treatment of hepatocytes with either NABQI (0.4 mM) or paracetamol (2 mM) alone resulted in a considerable loss of cell viability, as assessed by trypan blue exclusion or leakage of lactate dehydrogenase, accompanied by an increase in the percentage of viable cells that were blebbed. N-acetyl-L-cysteine (1.25 mM) pretreatment diminished the loss of cell viability and the percentage of blebbed cells resulting from exposure to NABQI or paracetamol, whereas iloprost (10(-16) M to 10(-10) M) pretreatment reduced only the loss of cell viability, not the percentage of viable cells exhibiting blebbing. Pretreatment with N-acetyl-L-cysteine significantly attenuated the depletion by paracetamol of glutathione and decreased the covalent binding of [14C]-paracetamol to cellular proteins, whereas iloprost was without any such effects. 3 The effects of iloprost and N-acetyl-L-cysteine were also investigated by use of a model of paracetamol toxicity in which it is possible to study the biochemical events leading to cell injury separate from the generation of toxic metabolites. Hamster hepatocytes were incubated with paracetamol (4 mM) for 90 min at 37 degrees C during which metabolism of paracetamol occurs with minimal loss of cell viability.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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