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991.
992.
Breus' mole (massive subchorionic hematoma) is a rare entity most often found in the placentae of macerated stillborn fetuses. Previously considered to represent a postmortem event, recent evidence suggests that it occurs prior to fetal demise. A 23-week gestation male neonate was delivered of a 23-year-old gravida 3, para 2 woman and survived for 49 min. An autopsy with chromosomal studies resulted in a diagnosis of triploidy. Placental examination showed the presence of both Breus' mole and also partial hydatidiform mole. DNA samples extracted from portions of the fresh hematoma and from the fetal spleen were compared using molecular techniques. PCR analysis showed the presence of Y chromosome specific DNA in the placental clot, but a semiquantitative Southern blot demonstrated that roughly 85% of the clot DNA was of maternal origin. These findings suggest that Breus' mole represents primarily maternal thrombosis rather than fetal hemorrhage. We hypothesize that the partial mole could have contributed to the formation of the Breus' mole as some of the hydropic villi may have focally obstructed the maternal venous return from the intervillus space causing sluggish flow and promoting thrombosis. A review of the literature on Breus' mole shows that the majority of reported cases have not included cytogenetic findings. However, several authors have reported an association with triploidy and other chromosomal anomalies characterized by scattered placental hydropic villi. Thus, we suggest that obstruction of maternal venous return by hydropic villi may have played a contributory role in some of these other reported cases.  相似文献   
993.
994.
BACKGROUND: Older patients (aged >65 years) may experience drug-related problems that, if unrecognized, can result in drug-related morbidities (DRMs). According to the literature, 49% to 76% of all DRMs may be preventable; however, there is little consensus as to which are preventable and which are not. OBJECTIVE: The aim of this study was to develop consensus-approved clinical indicators of preventable DRM (PDRM) in older adults. Geriatricians, clinical pharmacologists, general practitioners, and clinical pharmacists were included in the consensus-building process. METHODS: In 2001, a survey containing potential indicators of PDRM was prepared based on previous research and the input of 2 clinical pharmacists. The survey was administered concurrently via the Delphi technique to 2 separate specialist panels (6 geriatricians and 6 clinical pharmacologists) to generate clinical indicators of PDRMs in older adults. Subsequently, a focus group of 12 general practitioners (GPs) assessed these PDRM indicators in Nova Scotia, Canada. RESULTS: The specialist panels generated 58 consensus-approved clinical indicators of PDRMs in older adults after 2 rounds of the Delphi technique. The GPs agreed with 52 (90%) of these PDRM indicators. CONCLUSIONS: This study generated consensus-approved indicators of PDRMs in older adults, which could be used by health professionals to identify patients at risk for PDRMs. The indicators could also have a role in quality measurement systems and in epidemiologic research. Furthermore, the indicators could complement existing clinical indicators and establish an important link between patterns of care and clinical outcomes.  相似文献   
995.
Whereas making decisions during menopause can be challenging for all women, those with physical impairments face special issues with respect to menopause in general and hormone replacement therapy (HRT) in particular. In this correlational study the authors explored the factors such women consider when making decisions about HRT One hundred sixty-seven women with physical impairments throughout the United States completed surveys concerning their attitudes and knowledge about HRT Approximately half the menopausal women were currently taking HRT The strongest predictor of HRT use was women's perceptions of their health care providers opinions about their taking HRT, combined with their motivation to comply with the provider's recommendation. Thisfinding points to the significant role that nurses and other health care providers play in assisting women to make informed health care choices during menopause.  相似文献   
996.
997.
To compare long-term virologic benefits of antiretroviral regimens in persons with advanced human immunodeficiency virus (HIV) disease, a randomized, open-label study was conducted of 517 subjects with no or limited previous experience with antiretroviral therapy. Subjects received lamivudine plus zidovudine and indinavir (indinavir group), efavirenz plus indinavir (efavirenz + indinavir group), or nelfinavir plus indinavir (nelfinavir + indinavir group) and were monitored for 2.1 years. Virologic failure was lower in the efavirenz + indinavir group (P=.04) and higher in the nelfinavir + indinavir group (P=.006), compared with that in the indinavir group. No difference in grade 3 or 4 adverse event rates in the efavirenz + indinavir group (P=.97) and a trend toward an increased rate in the nelfinavir + indinavir group (P=.07), compared with the indinavir group, were noted. A 4-drug regimen containing efavirenz plus indinavir resulted in a superior virologic response, whereas one containing nelfinavir plus indinavir resulted in an inferior response and a greater likelihood of toxicity.  相似文献   
998.
BACKGROUND: Cardiac transplantation (CTX) improves exercise tolerance, but CTX recipients still achieve only 50% to 70% of normal values for exercise capacity. Among the factors suggested to explain the reduced exercise tolerance in CTX recipients is deconditioning. Little is known about the relation between physical activity patterns and exercise test responses in CTX patients. METHODS: Forty-seven CTX patients (mean age 47 +/- 12 years; mean 4.8 +/- 3.0 years after CTX) underwent maximal exercise testing and assessment of current and past physical activity patterns using a questionnaire. Energy expenditure from recreational and occupational activities over the last year and for adulthood were expressed in kcal/week and correlated with peak oxygen consumption (VO(2)), VO(2) at the ventilatory threshold, and the percentage of age-predicted peak VO(2) achieved. RESULTS: The patients reported expending a mean of approximately 1100 kcal/week in recreational activity, suggesting a moderate level of physical activity is maintained after CTX. The mean peak VO(2) achieved for the group was 17.2 +/- 5.2 mL/kg/min, corresponding to 59% +/- 14% of age-predicted exercise capacity. Significant but modest associations were observed between recreational energy expenditure during the last year and percentage of age-predicted peak VO(2) achieved (r = 0.34, P <.01), and VO(2) at the ventilatory threshold (r = 0.45, P <.01). Energy expenditure from blocks walked and stairs climbed per week was modestly associated with peak VO(2) (r = 0.36, P <.05), percentage of predicted peak VO(2) achieved (r = 0.39, P <.01), and VO(2) at the ventilatory threshold (r = 0.42, P <.01). Exercise capacity was poorly related to occupational and recreational activities when expressed as average weekly energy expended throughout adulthood. CONCLUSION: Post-CTX patients maintain a moderately active lifestyle. Measures of exercise tolerance generally are related to recent daily recreational activities in CTX patients, but these associations are modest. The many physiologic factors unique to CTX recipients likely play a more important role than deconditioning in determining exercise tolerance in these patients.  相似文献   
999.
Elevated serum nonesterified free fatty acid (NEFA) concentrations are detrimental to both the mechanical and electrical function of the heart. A(1) adenosine receptor agonists are potent and efficacious inhibitors of lipolysis; however, their cardiovascular effects have limited their use to lower serum NEFA. Our objective was to determine whether the antilipolytic effect of N-[3-(R)-tetrahydrofuranyl]-6-aminopurine riboside (CVT-510), an A(1) agonist, could be distinguished from its bradycardia effect and demonstrated in rats with normal or elevated serum NEFA. Rats were instrumented with telemetry transmitters for continuous recording of heart rate, and catheterized, for delivery of drugs and blood sampling. CVT-510 caused a rapid and sustained dose-dependent decrease in NEFA at doses that did not cause bradycardia (2, 5, and 20 micro g/kg). Significant bradycardia was observed at 50 micro g/kg. Norepinephrine (NE) increased NEFA from 0.5 +/- 0.01 to 0.9 +/- 0.2 mM and this effect lasted for 2 h. CVT-510 (10 micro g/kg) given at 40 min postinjection of NE reversed the rise in NEFA (69% reduction). When CVT-510 (20 micro g/kg) was given 15 min before a 30-min long infusion of NE, the lipolytic response to NE was prevented. To mimic the antilipolytic effect of CVT-510 in awake rats, hearts were perfused with palmitate at concentrations similar to those observed in the in vivo studies (0.8 and 0.2 mM), which decreased myocardial oxygen consumption (MVO(2)) by 11%. Thus, CVT-510 at doses > or =5-fold lower than those that slow heart rate caused a marked and sustained lowering of normal or elevated NEFA, that when mimicked in vitro decreased MVO(2) and would be expected to improve cardiac efficiency.  相似文献   
1000.
Ineffective, ill-tempered managers hurt employee morale and productivity. Learn what behaviors characterize toxic managers, how they damage an organization, and how to lessen their impact.  相似文献   
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