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71.
Familial aggregation of bone mineral density (BMD) and bone mineral content (BMC) has been shown in twin and familial studies, but most sample sizes were small. We here report a large familial aggregation study in a Chinese population. A total of 13,973 siblings aged 25–64 years from 3,882 families were enrolled from Anhui, China. We assessed the whole-body, hip and lumbar spine BMD and BMC by dual-energy X-ray absorptiometry (DXA). Intra-class correlation coefficients of BMD and BMC between siblings varied among different skeletal sites and between different age groups of male sib-pairs and premenopausal and postmenopausal female sib-pairs, with a range of 0.228 to 0.397. The sibling recurrence risk ratio (s) of osteoporosis was 2.6 in our population. We also evaluated the joint association of the BMD values of the first siblings and the second siblings with the risk of low BMD (defined as less than the 10th percentile of the same group population) of their younger siblings. If both the first and second siblings BMDs were in the lowest tertile, the odd ratios (ORs) of low BMD in their subsequent siblings were 8.32 [95% confidence interval (CI) 5.59–12.39)], 8.71 (95% CI 5.74–13.22) and 5.90 (95% CI 3.57–9.76) for total body, total hip and lumbar spine, respectively. This study demonstrates a significant familial aggregation of BMD and BMC in a large sample of rural Chinese adults.  相似文献   
72.
Leucocyte agglutinins and birth weight   总被引:2,自引:0,他引:2  
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Does the ability of medical students to assess and relate to their patients through the psychiatric interview reflect in traditional academic achievement scores? A previous publication by our group offers data suggesting that certain personality traits of final year medical students have a fundamental importance in determining a successful performance on a psychiatry rotation. As the literature is vague and contradictory about the relationship between the psychiatric interview and clinical performance, a study was developed to determine what outcome variables are associated with the performance of clinical clerks on the Psychiatric Interview. An attempt was made to develop and test a new scale designed to measure the Psychiatric Interview. The Psychiatric Interview Scale was used to measure performance on 33 final year medical students on a 1 month psychiatry rotation at a University of Toronto teaching hospital, and subsequently, as a basis for analysis and training of these students in interviewing. Inter-rater reliability of the Psychiatric Interview Scale was rho = 0.72 and internal reliability was 0.74. Psychiatric Interview Scores were compared with other achievement scores, and with patients' ratings of the students interviews. A significant correlation emerged between the Psychiatric interview scores and final clinical examinations, but surprisingly, there was no relationship between the patients' evaluation of the Psychiatric Interview and the raters' evaluations and a strongly significant negative correlation between patients' ratings and clinical scores.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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Adkins AL  Robbins J  Villalba M  Bendick P  Shanley CJ 《The American surgeon》2004,70(2):137-40; discussion 140
Despite surgical advances, antimicrobial therapy, and intensive care, the morbidity and mortality of intra-abdominal sepsis remains high. The primary purpose of this study was to determine whether open abdomen management of intra-abdominal sepsis reduces intensive care unit (ICU) and hospital mortality. The records of 81 consecutive patients with open abdomen management for intra-abdominal sepsis admitted to the surgical ICU from January 1998 to April 2002 were retrospectively reviewed. Outcomes were compared to a historical control group with primary abdominal closure, also admitted to the surgical ICU with intra-abdominal sepsis and matched for sex, age, source of sepsis, and APACHE III score. ICU mortality for the open abdomen group was 25 per cent versus 17 per cent for the control group. Hospital mortality was 33 per cent and 25 per cent for the open abdomen patients and historical controls, respectively. Both ICU and hospital length of stay were significantly longer for the open abdomen group. An overall fistula rate of 14.8 per cent was demonstrated in the open abdomen patients. A significant difference in overall ICU and hospital mortality was not demonstrated between patients treated with open abdomen management and historical controls. A prospective randomized study accounting for extent of sepsis may define a role for open abdomen management in selected subgroups of patients.  相似文献   
78.
Motor nerve terminals in adult mammalian slow-twitch muscles have lower levels of spontaneous and evoked neurotransmitter release than terminals in fast-twitch muscles. These reflect adaptive differences, allowing terminals in slow (postural) muscles to sustain release during the prolonged firing trains experienced in vivo. Here we ask whether these differences in terminal release properties in Sprague-Dawley rat extensor digitorum longus (EDL, fast) and soleus (slow) muscles reflect their early cytodifferentiation in the embryo or whether they might be adaptations to their distinct mature activity patterns, which emerge around two weeks postnatally. We find that the mature pattern of differences in release arise through co-ordinated increases in presynaptically dependent release properties (quantal content, spontaneous release frequency and evoked potential amplitude), beginning at three weeks, which are particularly substantial in EDL. In contrast, other synaptic properties are either consistently greater in the same muscle throughout development (evoked potential kinetics, muscle fibre diameter) or display no systematic muscle type-dependent differences (terminal area, input resistance, spontaneous release amplitude). Thus, the emergence of adaptive differences in terminal release properties correlates with the differentiation of locomotor activity patterns in postnatal rat hindlimb muscles.  相似文献   
79.
Antibiotics are known to have antichloroplastic properties, but their effects on aquatic higher plants are virtually unknown. In order to address this issue, 25 pharmaceuticals, including 22 antibiotics, were assessed for phytotoxicity to the aquatic higher plant Lemna gibba. A 7-d static-renewal test was used, and plants were treated with 0, 10, 30, 100, 300, and 1,000 microg/L of pharmaceutical-containing growth media. Phytotoxicity was assessed using multiple growth and biochemical endpoints. Effective concentration (EC)50, EC25, and EC10 values as well as tests for significant differences between treatments and controls lowest-observed-effect concentration (LOECs) were calculated for each endpoint. Twelve different classes of antibiotics were assessed; however, only members of the fluoroquinolone, sulfonamide, and tetracycline classes of antibiotics displayed significant phytotoxicity. The most toxic members of each of these classes tested were lomefloxacin, sulfamethoxazole, and chlortetracycline, with wet weight EC25 values of 38, 37, and 114 microg/L, respectively. Injury symptoms were comparatively uniform and consistent among chemical classes while degree of phytotoxicity varied considerably. Both of these criteria varied markedly between classes. Wet mass was consistently the most sensitive endpoint above 100 microg/L; conversely, frond number was the most sensitive below 100 microg/L. Pigment endpoints were significantly less sensitive than growth endpoints.  相似文献   
80.
Aquatic persistence of eight pharmaceuticals in a microcosm study   总被引:1,自引:0,他引:1  
The persistence of eight pharmaceuticals from multiple classes was studied in aquatic outdoor field microcosms. A method was developed for the determination of a mixture of acetaminophen, atorvastatin, caffeine, carbamazepine, levofloxacin, sertraline, sulfamethoxazole, and trimethoprim at microg/L levels from surface water of the microcosms using solid phase extraction and high-performance liquid chromatography-ultraviolet (HPLC-UV) and liquid chromatography tandem mass spectrometry (LC-MS-MS). Half-lives in the field ranged from 1.5 to 82 d. Laboratory persistence tests were performed to determine the relative importance of possible loss processes in the microcosms over the course of the study. Results from dark control experiments suggest hydrolysis was not important in the loss of the compounds. No significant differences were observed between measured half-lives of the pharmaceuticals in sunlight-exposed pond water and autoclaved pond water, which suggests photodegradation was important in limiting their persistence, and biodegradation was not an important loss process in surface water over the duration of the study. Observed photoproducts of several of the pharmaceuticals remained photoreactive, which led to further degradation in irradiated surface waters.  相似文献   
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