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141.
OBJECTIVE: The authors compared service utilization and costs for acutely ill psychiatric patients treated in a day hospital/crisis respite program or in a hospital inpatient program. METHOD: The patients (N = 197) were randomly assigned to one of the two programs and followed for 10 months after discharge. Both programs were provided by a community mental health center (CMHC) in a poor urban community. Data were collected for developing service utilization profiles and estimates of per-unit costs of the inpatient, day hospital, and outpatient services provided by the CMHC. RESULTS: On average, the day hospital/crisis respite program cost less than inpatient hospitalization. The average saving per patient was +7,100, or roughly 20% of the total direct costs. There were no significant differences between programs in service utilization or costs during the follow-up phase. Cost savings accrued in the index episode because per-unit costs were lower for day hospital/crisis respite and the average stay was shorter. Significant differences in cost were found among patient groups with psychosis, affective disorders, and dual diagnoses; psychotic patients had the highest costs in both programs. The two programs had roughly equal direct service staff and capital costs but significantly different operating costs (day hospital/crisis respite operating costs were 51% of inpatient hospital costs). CONCLUSIONS: The programs were equally effective, but day hospital/crisis respite treatment was less expensive for some patients. Potential cost savings are higher for nonpsychotic patients. Cost differences between the programs are driven by the hospital's relatively higher overhead costs. The roughly equal expenditures for direct service staff costs in the two programs may be an important clue for understanding why these programs provided equally effective acute care.  相似文献   
142.
OBJECTIVE: To study the effects of estrogen on transendothelial paracellular permeability in women. METHODS: Human umbilical vein endothelial cells (HUVEC) obtained from women were grown on filters. The paracellular permeability characteristics were determined in terms of changes in the permeability to the polar acid pyranine (Ppyr) and as changes in the transendothelial electrical resistance (RTE). Tight junctional resistance characteristics were assayed by lowering luminal NaCl and measuring the dilution potential, and were expressed as the ratio of monoion mobility uCl/uNa (cation selectivity). RESULTS: Low extracellular calcium and hyperosmolarity increased Ppyr and decreased RTE. The former but not the latter condition abolished the endothelium-specific cation selectivity. Treatment with 10 nM of estradiol-17 beta had no effect on RTE, but it increased the cation selectivity. The effect of estradiol required 1-6 hours' incubation with the hormone; it was dose dependent and saturable, with a median effective concentration of estradiol of 1 nM. Diethylstilbestrol, but not estriol, could mimic the effect of estradiol, and the estrogen receptor antagonist ICI-182, 780 blocked it. CONCLUSION: Cultured HUVEC cells form patent tight junctions. Estrogens increase the cation selectivity across HUVEC cultures. The effect of estrogen may be mediated by an estrogen receptor. These effects may be important for vasculoprotection in cases of sudden changes in ions levels across the capillary wall, such as ischemia or reperfusion.  相似文献   
143.
144.
Treatment of patients with type IIA hyperlipoproteinemia (HLP) with pravastatin for 3 months led to significant decreases (p < 0.001) in total cholesterol (7.18 +/- 0.30 to 5.75 +/- 0.30 mmol/L), LDL cholesterol (5.56 +/- 0.33 to 4.02 +/- 0.32 mmol/L), and ratio of total cholesterol to HDL cholesterol (6.5 +/- 0.4 to 4.6 +/- 0.4). Decreases of a similar magnitude were also seen in patients with type IIB HLP. Plasma glucose and insulin concentrations after an oral glucose load and from 8 AM to 4PM in response to meals were higher in patients with Type IIB HLP, who also had higher steady-state plasma glucose concentrations after an infusion of somatostatin, insulin, and glucose (12.4 +/- 1 vs 5.5 +/- 0.8 mmol/L, p < 0.001). Because steady-state plasma insulin concentrations were similar in both groups, patients with type IIB HLP were relatively insulin resistant. Furthermore, day-long plasma glucose concentrations and insulin resistance were modestly, but significantly (p < 0.01), greater after treatment in both groups. In conclusion, LDL cholesterol metabolism improved in hypercholesterolemic subjects treated with pravastatin, but the hypertriglyceridemia, insulin resistance, relative glucose intolerance, and hyperinsulinemia present in patients with type IIB HLP either did not improve with treatment or was somewhat worse.  相似文献   
145.
We retrospectively determined the prevalence and nature of mortality as many as ninety days after 2736 primary and revision total hip arthroplasties performed in 2002 patients by one surgeon at a teaching hospital between January 1969 and December 1996. All but seventy-one of the patients had received prophylaxis against venous thromboembolic disease. There were no intraoperative deaths, and no events during the operation could be linked directly to postoperative mortality. Eight deaths (mortality rate, 0.3 per cent) occurred within ninety days after the 2736 procedures. Four deaths (mortality rate, 0.15 per cent) occurred during the initial hospitalization. The cause of seven of the deaths was determined. Three patients died as a result of preexisting disease (severe hepatorenal disease, metastatic esophageal cancer, or severe cardiac disease), and one patient died from sepsis with a gram-negative organism during a thoracotomy eight days postoperatively. A bleeding complication that occurred while the patient was receiving warfarin therapy led to the death of two other patients; one of these deaths occurred in 1974 and the other, in 1982. At the time that these patients were managed, the desired prothrombin time was considered to be twice the control value. The remaining patient, who had had a clip placed on the inferior vena cava after a pulmonary embolus occurred in 1970, died secondary to acute, severe thrombosis of this vessel after a total hip arthroplasty in 1971. The patient for whom the cause of death was not determined had had an artificial aortic valve and had been receiving chronic warfarin therapy. She died suddenly eighty-nine days postoperatively; no autopsy was performed. No patient died as the direct result of a known pulmonary embolus. No deaths related to venous thromboembolic disease or its prophylaxis or treatment occurred after 1982 (1458 operations). We attribute this, in part, to reduced levels of warfarin prophylaxis and improved management with warfarin. The ninety-day postoperative mortality rate after 2736 procedures performed over nearly three decades was low (0.3 per cent). This span of time included the period before the introduction of many current improvements in perioperative care, such as routine intubation of patients under general anesthesia, continuous monitoring of the electrocardiogram intraoperatively, and blood-gas determinations. When the patients who died as a result of known, severe preexisting disease were excluded, the mortality rate was 0.18 per cent (five of 2733).  相似文献   
146.
Clinical records were reviewed to examine the effectiveness of stapedectomy in patients 70 years and older. A total of 154 patients was studied, including 11 with profound hearing loss with long-standing otosclerosis. Ages at the time of surgery ranged from 70 to 92 years (mean, 76.3 years). The mean pure-tone average (500, 1,000, 2,000, and 4,000 Hz) improved 30.6 dB after surgery for the 143 patients in the main otosclerotic group and 26.8 dB for the patients in the profound-hearing-loss group. The rate of successful stapedectomies for the 70(+)-year-old patients (90.9%) and the younger comparison group (90.0%) were similar. These findings extend the documented range of stapedectomy as a safe and effective procedure through the eighth decade of life.  相似文献   
147.
Ninety-two-kilodalton type IV collagenase (MMP-9) is present in aortic aneurysms and may be important to the pathogenesis of this disease. Alteration in expression of MMP-9 or its inhibitor, the tissue inhibitor of metalloproteinase type 1 (TIMP-1), could increase degradation of extracellular matrix and lead to aneurysm formation. The purpose of this study was (1) to measure tissue levels of MMP-9 and TIMP-1 mRNA in aneurysmal (AAA), atherosclerotic occlusive (AOD), and normal (NL) human infrarenal aorta; (2) to test for their expression by cultured AAA and NL vascular smooth muscle cells (VSMCs); and (3) to locate in situ the cells responsible for mRNA production within AAA, AOD, and NL aortic wall. Total RNA extracted from AAA (n = 8), AOD (n = 8), and NL (n = 7) tissue was subjected to Northern analysis. Signals for MMP-9 and TIMP-1 were normalized to alpha-tubulin. Mean values +/- SEM were compared by ANOVA. NL and AAA VSMCs were cultured, passaged, and grown to confluence before RNA extraction and Northern analysis. In situ hybridization with digoxigenin-labeled RNA probes localized cells responsible for MMP-9 and TIMP-1 mRNA expression within sections of AAA (n = 5), AOD (n = 2), and NL (n = 2) aorta. MMP-9 mRNA levels were significantly greater in AAA (0.855 +/- 0.180) than NL (0.046 +/- 0.23) (P < .02), but differences between AOD (0.406 +/- 0.196) and AAA or AOD and NL were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
148.
BACKGROUND: This is a retrospective study to evaluate the incidence of heterotopic ossification (HO) in cemented and uncemented femoral neck fractures treated with Bateman bipolar hemiarthroplasty. METHODS: From October 1985 to July 1990, there were 451 cases of displaced intracapsular fractures of the femoral neck treated with Bateman bipolar hemiarthroplasty (261 uncemented vs 190 cemented) at the Veterans General Hospital-Taipei. RESULTS: After an average follow-up of 46 months, there was more HO in the cemented group than in the uncemented group (p = 0.014, chi-squared test). The average surgical time was approximately 20 minutes longer and the average blood loss was approximately 160 ml more in the cemented Bateman bipolar hemiarthroplasty group. CONCLUSIONS: HO formation is more common in cemented Bateman bipolar hemiarthroplasty than in the uncemented procedure. The incidence of HO is not related to age or sex.  相似文献   
149.
Autosomal dominant familial spastic paraplegia (FSP) is a genetically heterogeneous neurodegenerative disorder displaying anticipation for which three loci have been mapped to the chromosomal positions 14q11.2-q24.3 (SPG3), 2p21-p24 (SPG4) and 15q11.1 (SPG6). The repeat expansion detection (RED) method has been used to demonstrate expanded CAG repeats in some FSP families that map to SPG4. We analyzed 20 FSP families, including four for which there is evidence for linkage to SPG4, and found that in most cases the repeat expansion detected by RED is due to non-pathogenic expansions of the chromosome 18q21.1 SEF2-1 or 17q21.3 ERDA1 locus. Polymorphic expansions at SEF2-1 and ERDA1 appear frequent and may confound RED studies in the search for genes causing disorders demonstrating anticipation. In six FSP families, however, CAG repeat expansion was detected in a subset of affected and at-risk individuals that did not result from expansion of the SEF2-1 and ERDA1 loci. Overall, 11 of 37 (30%) of the FSP patients with a CAG/CTG repeat expansion are unaccounted for by the SEF2-1 and ERDA1 loci, compared with two of 23 (9%) of the unaffected at-risk individuals and none of 19 controls. In the majority of cases these novel expansions were shorter than those previously reported.  相似文献   
150.
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