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41.
Ultrasound scans of 51 consecutive patients with gallbladder wall thickening were reviewed, and specific sonographic features were correlated with surgical and clinical follow-up. Two patterns of thickening were identified as specific indicators of the presence or absence of acute cholecystitis. "Striated" wall thickening, consisting of several alternating, irregular, discontinuous, lucent and echogenic bands, was seen in eight of 13 patients (62%) with acute cholecystitis. This pattern was not encountered in any of the patients who did not have acute cholecystitis. Conversely, "three-layer" thickening, consisting of a single circumferential lucent zone between two relatively uniform echogenic layers, was seen in only one of 13 patients (8%) with acute cholecystitis but in 11 of 38 patients (29%) with other diagnoses. Other abnormalities, including the presence of intramural echogenic foci and wall irregularities, were more frequently seen in patients with acute cholecystitis but were not as helpful. Use of these features may suggest or help exclude a diagnosis of acute cholecystitis in those patients in whom the cause of gallbladder wall thickening is otherwise not apparent.  相似文献   
42.
Yoga interventions can reduce stress, but the mechanisms underlying that stress reduction remain largely unidentified. Understanding how yoga works is essential to optimizing interventions. The present study tested five potential psychosocial mechanisms (increased mindfulness, interoceptive awareness, spiritual well-being, self-compassion and self-control) that have been proposed to explain yoga's impact on stress. Forty-two participants (62% female; 64% White) in a yoga program for stress reduction completed surveys at baseline (T1), mid-intervention (T2) and post-intervention (12 weeks; T3). We measured two aspects of stress, perceived stress and stress reactivity. Changes were assessed with paired t-tests; associations between changes in mechanisms were tested in residual change models. Only stress reactivity decreased, on average, from T1 to T3. Except for self-compassion, all psychosocial mechanisms increased from T1 to T3, with minimal changes from T2 to T3. Except for self-control, increases in each mechanism were strongly associated with decreases in both measures of stress between T1 and T2 and decreases in perceived stress from T1 to T3 (all p's < 0.05). Increased psychosocial resources are associated with stress reduction. Yoga interventions targeting these resources may show stronger stress reduction effects. Future research should test these linkages more rigorously using active comparison groups and larger samples.  相似文献   
43.

This study examined reasons for romantic and sexual relationships with adult partners among men with pedohebephilic preferences (N?=?125). We also explored whether age sexual orientation impacted reasons for engaging in sex with adult partners. Pedohebephilic men endorsed both non-sexual and sexual reasons for engaging in adult-partnered relationships. The top reasons for sexual relationships with adult partners were pleasure, love and commitment, physical desirability, experience seeking, and practicality. The top reasons for romantic relationships with adult partners were to gain companionship, love toward romantic partner, to escape loneliness, to engage in sexual activities, and it seemed natural. The exclusivity of attraction to children was found to be significantly related to some of the factors. These findings support differential reasons for pedophilic men engaging in adult-partnered relationships. Professionals should seek to understand the nature of their clients’ relationships and age sexual orientation to determine whether such factors are relevant. Professionals can then support clients in their search for meaningful relationships.

  相似文献   
44.
Advances in techniques of molecular biology have made possible the amplification of specific genes from single cells. This has a major clinical application in preimplantation diagnosis of monogenic disorders. However, the incidence of allele specific amplification failure (allele drop out) in heterozygous single cells can lead to misdiagnosis and the transfer of affected embryos. Few studies have been done to investigate the actual cause of allele drop out, although some investigators have succeeded in reducing but not eliminating it. Here we report the efficiency of amplifying both alleles in heterozygous cells lysed according to two different protocols. A total of 177 heterozygous cells from carriers of cystic fibrosis (CF) and haemoglobin C (HbC) were lysed using two different lysis buffers. Interestingly none of the cells that were lysed with sodium dodecyl sulphate/proteinase K showed any example of allele specific amplification failure whereas in those lysed by KOH/dithiothreitol it was present in 17.6 and 4.7% of the CF and HbC cells respectively. Our results suggest that the phenomenon of allele specific amplification failure is at least in part dependent on the lysis buffer used.   相似文献   
45.
Research Objectives: To develop population-based estimates of estrogen replacement therapy use rates in 1995 among women over age 65 living in the community; to estimate the impact of socioeconomic and health characteristics on estrogen use. Method: Estimates are based on a large, nationally representative sample of Medicare beneficiaries; detailed self-report data were merged with Medicare claims. Results: Overall, 13.1% of women reported use of estrogen replacement therapy in 1995. Estrogen users were more likely to be white, age 65–74, with private insurance, high income, history of osteoporosis and heart problems, no history of breast cancer, and a patient of gynecologists. Conclusions: Estrogen use was substantially lower among the socioeconomically disadvantaged, controlling for medical history variables, suggesting considerable inequity in access to estrogen replacement therapy treatment.  相似文献   
46.
OBJECTIVE: To analyze hospitalization patterns of persons with AIDS (PWAs) in a multi-state/multi-episode continuous time duration framework. DATA SOURCES: PWAs on Medicaid identified through a match between the state's AIDS Registry and Medicaid eligibility files; hospital admission and discharge dates identified through Medicaid claims. STUDY DESIGN: Using a Weibull event history framework, we model the hazard of transition between hospitalized and community spells, incorporating the competing risk of death in each of these states. Simulations are used to translate these parameters into readily interpretable estimates of length of stay, the probability that a hospitalization will end in death, and the probability that a nonhospitalized person will be hospitalized within 90 days. PRINCIPAL FINDINGS: In multivariate analyses, participation in a Medicaid waiver program offering case management and home care was associated with hospital stays 1.3 days shorter than for nonparticipants. African American race and Hispanic ethnicity were associated with hospital stays 1.2 days and 1.0 day longer than for non-Hispanic whites; African Americans also experienced more frequent hospital admissions. Residents of the high-HIV-prevalence area of the state had more frequent admissions and stays two days longer than those residing elsewhere in the state. Older PWAs experienced less frequent hospital admissions but longer stays, with hospitalizations of 55-year-olds lasting 8.25 days longer than those of 25-year-olds. CONCLUSIONS: Much socioeconomic and geographic variability exists both in the incidence and in the duration of hospitalization among persons with AIDS in New Jersey. Event history analysis provides a useful statistical framework for analysis of these variations, deals appropriately with data in which duration of observation varies from individual to individual, and permits the competing risk of death to be incorporated into the model. Transition models of this type have broad applicability in modeling the risk and duration of hospitalization in chronic illnesses.  相似文献   
47.
OBJECTIVE: To assess the clinical validity of clinical diagnostic criteria for dementia with Lewy bodies (DLB). METHODS: We assessed the sensitivity, specificity, and positive and negative predictive values of the clinical criteria of the Consortium on dementia with Lewy Bodies (CDLB) in 18 patients with autopsy-proven DLB and in 76 patients with dementia not associated with Lewy bodies, using postmortem diagnosis as a gold standard. RESULTS: CDLB criteria had either high sensitivity or high specificity, but no set of criteria simultaneously provided both high sensitivity and high specificity. Clinical criteria had higher predictive validity in patients with pure DLB than in patients with DLB and AD. Seventy-eight percent of patients with pure DLB had two or more major criteria, compared with 44% of patients with DLB and AD (p<0.02). If the nine patients with DLB and AD were excluded from the DLB group, the CDLB criteria for probable DLB had sensitivity of 78% and specificity of 85%. CDLB criteria for probable DLB (two or more major criteria) distinguished DLB from AD with a sensitivity of 78% and a specificity of 64%. CONCLUSIONS: The proposed CDLB criteria have high negative predictive value and thus do well at excluding patients with DLB. Positive predictive value of 75% can be achieved by a combination of any three major or minor criteria, providing the analysis is confined to patients with mild to moderate dementia. Criteria were most accurate if confined to patients with pure DLB who had mild to moderate dementia.  相似文献   
48.
In a simulated field trial Bacillus thuringiensis var israelensis (BTI) pellet formulation exhibited an enhanced efficacy with increasing dose. A dosage of 1.0 and 1.5 ppm was most effective under simulated field conditions. In field trials persistence of BTI pellet (1.0 ppm) was observed for 35 days in moderately polluted water collection as compared to 21 days in highly polluted water bodies.KEY WORDS: Bacillus thuringiensis, Malaria, Mosquito control  相似文献   
49.
Objectives: The purpose of this study was to examine gender and ethnic differences in survival of persons receiving treatment for HIV infection to determine if differences existed, and if they did, to assess the possibility of explaining these differences by examining other factors, such as age, disease severity when beginning treatment, alcohol, illicit drugs, tobacco, educational level, living arrangements, antiretroviral treatment, PCP prophylaxis, sexually transmitted diseases, mode of transmission and opportunistic infections.

Design: A retrospective cohort study of all clients receiving treatment at an HIV only clinic from its opening in early 1988 until the end of May 1993. Statistical methods used to examine the data included incidence density ratios, Kaplan‐Meier survival curves, Breslow (generalized Wilcoxon) tests of equality of survival curves and Cox proportional hazards models both with and without time dependent covariates.

Results: In the cohort (37% African American, 7% Hispanic American and 25% female), 220 deaths occurred during 1223 person years of follow‐up. Compared to European American males, the following incidence density ratios were observed: European American females: 0.50, Hispanic American females: 0.70, Hispanic American males: 0.96, African American females: 1.28 and African American males: 2.38. The differences were noted above for gender/ethnicity groups were significant at the p < 0.0001 level. After adjusting for disease stage (as measured by laboratory testing of CD4 positive T‐lymphocytes), educational level, and age, no differences in survival by gender or ethnicity remained. Disease stage and educational level had the greatest prognostic significance.

Conclusions: European Americans entered treatment at a much earlier disease stage (as measured by CD4 positive T‐lymphocyte counts) and had higher educational levels (a surrogate for socioeconomic status) than African Americans. These factors may explain the longer survival in European Americans as compared to African Americans in this cohort.  相似文献   

50.
CONTEXT: With the recent change in pathological criteria for Alzheimer disease (AD), a group of patients has emerged who do not meet pathological criteria for any well-characterized degenerative dementias. Whether these unclassified patients have vascular dementia or some other form of dementia is not known. OBJECTIVE: To determine the clinical characteristics, pathological substrate, and relative frequency of dementia not caused by well-characterized degenerative dementias. DESIGN/SETTING: Clinicopathological study of a prospectively observed sample of elderly nondemented and demented subjects recruited from our urban community. METHODS: In our series of 128 subjects with prospective neuropsychological evaluations as well as neuropathology, we identified 35 clinically nondemented subjects and 20 demented patients who did not meet pathological criteria for well-characterized degenerative dementias such as AD or dementia with Lewy bodies. The 20 demented patients were grouped together under the term dementia of unknown etiology (DUE). We compared clinical, genetic, neuropsychological, pathological, and neurochemical characteristics of the nondemented group, patients with DUE, and 28 patients with AD and no other pathological abnormality. RESULTS: Mean age at death for patients with DUE was 89.1 +/- 5.8 years compared with 79.9 +/- 11.4 years for AD (P<.001). Patients with AD and DUE did not differ in sex, risk factors, apolipoprotein E genotype, neuropsychological features, or neurological features. Hippocampal sclerosis (in 11 patients with dementia and no controls) and leukoencephalopathy (in 7 patients with dementia and 1 control) were associated with cognitive impairment; other vascular markers were not. Dementia of unknown etiology accounted for 5% of all cases of dementia among patients dying in their 70s, 21% for patients dying in their 80s, and 48% for patients dying in their 90s. CONCLUSIONS: A significant percentage of demented patients older than 80 years do not meet pathological criteria for AD or dementia with Lewy bodies. Hippocampal sclerosis and leukoencephalopathy are common in these patients but rare in clinically nondemented subjects.  相似文献   
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