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71.
72.
Recent studies have shown that carotid endarterectomy for significant lesions lowers the risk of stroke and also reduces medical costs by averting the high costs of strokes. However, there has been no information on the cost effect of duplex ultrasound examination which has evolved as the prime means of discovering these carotid lesions. This study reviewed the findings and management of 100 consecutive new patients referred for duplex ultrasound management of the carotid arteries and the cost effects resulting. Seventy-three patients with < 70% stenosis were managed non-operatively; the remaining 27 with 33 lesions producing > 70% stenosis were treated by carotid endarterectomy. It was estimated that 6.5 patients would have had a stroke within 18 months if not operated on. While the medical costs of these strokes would have been $958,838, the cost of avoiding them was $300,494; the result was a significant medical costs saving of $658,344.  相似文献   
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OBJECTIVES: The purpose of this study was to determine the prevalence of, and sociodemographic factors associated with, adult domestic violence within a Native American community. METHODS: Adult women in the community were surveyed. RESULTS: Of 371 eligible women, 341 (92%) were surveyed. Among respondents, 179 reported a history of at least 1 episode of domestic violence. Fifty-six (16.4%) reported violence within the previous 12 months. Age under 40 years and living in a household receiving governmental financial assistance were independently associated with 1-year prevalence of adult domestic violence. CONCLUSIONS: Adult domestic violence is prevalent within this Native American community. Additional research is required to characterize further the relationship between domestic violence and socioeconomic status.  相似文献   
75.
In an initial, and then a confirmatory experiment, adult, male lobsters were injected with solvent, ecdysterone (E, 2.0 mug/g live weight) or ecdysterone acetate (EAc, 2.5 or 5.0 mug/g live weight) emulsions in Freund's incomplete adjuvant (FIA). Control lobsters underwent no molts and only one death in the two cases. The E treated animals all died (average: exp. 1, 19.2 +/-2.1 days; exp. 2, 25.3 +/- 8 days). After the lobsters were treated twice with 2.5 mug EAc/g live weight, in the first experiment, four out of five molted and one died; in the second experiment six out of eight molted, one died and one remained refractory. The high EAc dose resulted in five deaths, one molt and two pseudomolts after one treatment. It is concluded that the use of the oil emulsion and EAc sufficiently slowed the release of free ecdysterone to allow complete premolt development in the lobster.  相似文献   
76.
We have previously established a vincristine resistant human lung cancer cell line (PC-9/VCR) by a stepwise exposure of parental line PC-9 to vincristine. In this study the resistant cells showed enhanced vincristine cytotoxicity in the presence of cytochalasin B and D. The increase in cytotoxicity was associated with an enhanced accumulation and a reduced efflux of vincristine. Colchicine and taxol had no effects on vincristine accumulation. Several cytoplasmic proteins were overexpressed in the resistant cells. The two major ones, with molecular weights of 58.8 kDa and 83.2 kDa, were shown by western blotting to be beta-tubulin and actin, respectively. The polymerized tubulin level in the resistant cells was significantly (p < 0.05) higher than that in the parental cells. These results suggest that the cellular cytoskeletons might play an important role in VCR resistance in the PC-9/VCR human lung cancer cell line.  相似文献   
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Standardized investigations on resting heart rate variability (HRV) should provide more information on acamprosate's human pharmacodynamic properties because acamprosate interacts with several neurotransmitter systems which are also involved in maintaining autonomic neurocardiac balance. We performed HRV measurements prospectively in 69 healthy controls and 19 chronic alcoholics to prove the hypotheses that: (1) compared to healthy controls, chronic alcoholics show disturbances in neurocardiac vagal function; and (2) in alcoholics, acamprosate treatment (6-8 days) should further decrease parasympathetic activity if acamprosate interacts with central gamma-aminobutyric acidA receptors in vivo. Cardiovagal dysfunction was initially present in 21% of the alcoholics. After treatment. however, their neurocardiac sympathetic-parasympathetic balance improved significantly.  相似文献   
79.
Cell-mediated immunity (CMI) to homologous spermatozoal antigens was studied in sixty-two males following vasectomy of a duration of 1-10 years. A group of twenty-two normal, fertile non-vasectomized males was also included in the study. The inhibition in the leucocyte migration test (LMT), in the presence of spermatozoal antigen, was taken as an index of CMI. Twenty of the sixty-two vasectomized males (32.2 percent) showed a positive LMT reaction. When the results were analysed with reference to the duration of vasectomy, it was noted that four cases each (22.2 percent), showed a positive LMT reaction in the groups 0-2 years, and 3.5 years. On the other hand twelve cases gave a positive reaction in the group 6-10 years (46.1 percent). It appears that the incidence of CMI to spermatozoa increases with the duration in vasectomy.  相似文献   
80.
Microvillar membrane (Vm) and transmural (Vt) potential differences were measured in proximal colon taken from pigs at birth and up to 10 days of age. 2. Vm remained independent of the age of the animal provided it was measured in the absence of methionine. The over-all mean was -43-3 mV. Adding methionine to fluid bathing the mucosal surface of new-born pig colon caused a 9-8 mV depolarization of Vm and a 6-7 mV increase in Vt. These effects, which were Na+-dependent, were not seen in the 10-day-old animal. 3. Substituting SO4(2-) for Cl- in methionine-free medium caused a hyperpolarization in Vm. Increasing the concentration of K+ caused corresponding depolarization. Substituting choline for Na+ had no effect on VmCl- and K+ movement across the microvillar membrane together account for the bulk of the measured membrane potential. These results apply to all stages of development. 4. Na+ uptake across the microvillar membrane of the new-born pig colon was increased in the presence of methionine. This effect disappeared in older animals. Na+ uptake in the absence of methionine doubled during the first 24 h of post-natal life. This increase was maintained using colons taken from older animals. 5. Methionine depolarization of Vm in the new-born pig colon is probably caused by the electrogenic influx of Na+. The ability of the colon to actively concentrate methionine within tis mucosa disappears at the same time as methionine ceases to affect Vm and Vt. It is suggested that methionine and Na+ form a ternary complex with a carrier in the brush border of the new-born pig colon and that this carrier is lost or modified during early post-natal development.  相似文献   
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