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排序方式: 共有501条查询结果,搜索用时 15 毫秒
41.
Stephen R. Pye Vinodh Devakumar Steven Boonen Herman Borghs Dirk Vanderschueren Judith E. Adams Kate A. Ward Gyorgy Bartfai Felipe F. Casanueva Joseph D. Finn Gianni Forti Aleksander Giwercman Thang S. Han Ilpo T. Huhtaniemi Krzysztof Kula Michael E. J. Lean Neil Pendleton Margus Punab Alan J. Silman Frederick C. W. Wu Terence W. O’Neill 《Calcified tissue international》2010,86(3):211-219
We examined the distribution of quantitative heel ultrasound (QUS) parameters in population samples of European men and looked at the influence of lifestyle factors on the occurrence of these parameters. Men aged between 40 and 79 years were recruited from eight European centers and invited to attend for an interviewer-assisted questionnaire, assessment of physical performance, and quantitative ultrasound (QUS) of the calcaneus (Hologic; Sahara). The relationships between QUS parameters and lifestyle variables were assessed using linear regression with adjustments for age, center, and weight. Three thousand two hundred fifty-eight men, mean age 60.0 years, were included in the analysis. A higher PASE score (upper vs. lower tertile) was associated with a higher BUA (β coefficient = 2.44 dB/Mhz), SOS (β = 6.83 m/s), and QUI (β = 3.87). Compared to those who were inactive, those who walked or cycled more than an hour per day had a higher BUA (β = 3.71 dB/Mhz), SOS (β = 6.97 m/s), and QUI (β = 4.50). A longer time to walk 50 ft was linked with a lower BUA (β = ?0.62 dB/Mhz), SOS (β = ?1.06 m/s), and QUI (β = ?0.69). Smoking was associated with a reduction in BUA, SOS, and QUI. There was a U-shaped association with frequency of alcohol consumption. Modification of lifestyle, including increasing physical activity and stopping smoking, may help optimize bone strength and reduce the risk of fracture in middle-aged and elderly European men. 相似文献
42.
Kate L Limer Stephen R Pye Wendy Thomson Steven Boonen Herman Borghs Dirk Vanderschueren Ilpo T Huhtaniemi Judith E Adams Kate A Ward Hazel Platt Debbie Payne Sally L John Gyorgy Bartfai Felipe Casanueva Joseph D Finn Gianni Forti Aleksander Giwercman Thang S Han Krzysztof Kula Michael E Lean Neil Pendleton Margus Punab Alan J Silman Frederick C Wu Terence W O'Neill 《Journal of bone and mineral research》2009,24(2):314-323
Genes involved in sex hormone pathways are candidates for influencing bone strength. Polymorphisms in these genes were tested for association with heel quantitative ultrasound (QUS) parameters in middle‐aged and elderly European men. Men 40–79 yr of age were recruited from population registers in eight European centers for the European Male Aging Study (EMAS). Polymorphisms were genotyped in AR, ESR1, ESR2, CYP19A1, CYP17A1, SHBG, SRD5A2, LHB, and LHCGR. QUS parameters broadband ultrasound attenuation (BUA) and speed of sound (SOS) were measured in the heel and used to derive BMD. The relationships between QUS parameters and polymorphisms were assessed using linear regression adjusting for age and center. A total of 2693 men, with a mean age of 60.1 ± 11.1 (SD) yr were included in the analysis. Their mean BUA was 80.0 ± 18.9 dB/Mhz, SOS was 1550.2 ± 34.1 m/s, and BMD was 0.542 ± 0.141 g/cm2. Significant associations were observed between multiple SNPs in a linkage disequilibrium (LD) block within CYP19A1, peaking at the TCT indel with the deletion allele associating with reduced ultrasound BMD in heterozygotes (β =?0.016, p = ?0.005) and homozygotes (β = ?0.029, p = 0.001). The results for BUA and SOS were similar. Significant associations with QUS parameters were also observed for the CAG repeat in AR and SNPs in CYP17A1, LHCGR, and ESR1. Our data confirm evidence of association between bone QUS parameters and polymorphisms in CYP19A1, as well as modest associations with polymorphisms in CYP17A1, ESR1, LHCGR, and AR in a population sample of European men; this supports a role for genetically determined sex hormone actions in influencing male bone health. 相似文献
43.
Diem Thuy le T Na-Bangchang K Hung le N Chong MT Van Thang N Van Binh N Danh PT 《Japanese journal of infectious diseases》2007,60(4):161-166
The clinical efficacy of the monotherapy involving the administration of a high dose of dihydroartemisinin (DHA 900 mg) for 5 days was compared with that of the combination regimen (DHA 600 mg + mefloquine [MQ] 750 mg) in an open randomized study in 90 patients with uncomplicated falciparum malaria in the southern part of Viet Nam. Patients were randomly treated with the DHA-5 day monotherapy regimen (300, 300, 100, 100, and 100 mg given at 0, 24, 48, 72, and 96 h) or the DHA-MQ combination regimen (300 mg DHA at 0 h, then 300 mg DHA plus 750 mg MQ at 24 h). The end points for comparison were the parasite and fever clearance times (PCT and FCT) and recrudescence rates (by day 28 for DHA-5 days and day 42 for DHA-MQ). Eighty-nine patients completed the trial per protocol, including 45 cases receiving DHA-5 day and 44 receiving DHA-MQ. There was no difference in clinical manifestations, parasitemia density or other laboratory tests between the two patient groups. The PCTs were 35.3 +/- 17.4 h (mean +/- SD; range, 12-96) and 37.8 +/- 19.2 h (range, 12-96), respectively for the DHA-5 day and DHA-MQ regimens (P > 0.05). Twelve patients receiving the DHA-5 day regimen relapsed with falciparum malaria by day 28 (26.7%) and 5 patients receiving the DHA-MQ regimen relapsed by day 42 (11.4%) (P=0.07). Survival analysis showed that the DHA-5 day regimen had a radical cure rate significantly lower than that of the DHA-MQ regimen (P=0.003). The high dose of DHA in the monotherapy regimen did not increase the efficacy of the treatment of patients with uncomplicated Plasmodium falciparum malaria. The DHA combination regimens are suggested to be the better regimens for DHA. 相似文献
44.
Background:
Management of femoral diaphyseal fractures in the age group of 6-16 years is controversial. There has been a resurgence worldwide for operative fixation.Materials and Methods:
Twenty-two children (18 boys, 4 girls) aged 6-16 years with recent (> 3 days) femoral diaphyseal fractures (20 closed, 2 open) were stabilized with Titanium Elastic Nail (TEN). These fractures were in proximal third (n=3), middle third (n=15) and in the distal third (n=4) 17 patients underwent surgery within seven days of their injury. The results were evaluated using Flynn''s scoring criteria. Statistical analysis was done using Fischer''s exact test.Results:
All 22 patients were available for evaluation after a mean of 26 months (14-36 months) of followup. Radiological union in all cases were achieved in a mean time of 8.7 weeks. Full weight bearing was possible in a mean time of 8.8 weeks. Mean duration of hospital stay was 9.8 days. The results were excellent in 13 patients (59.0%), successful in six (27.2%) and poor in three patients (13.6%). All patients had early return to school.Conclusion:
Intramedullary fixation titanium elastic nailing is an effective treatment of diaphyseal fractures of the femur in properly selected patients of the 6-16 years age group. 相似文献45.
Background:
Compartment syndrome is a potentially devastating condition. Increased intracompartmental pressure has been incriminated as the primary pathogenic factor in compartment syndrome. The purpose of this prospective study was to monitor the anterior compartmental pressure and differential pressure to minimize the incidence of acute compartment syndrome.Materials and Methods:
Seventy-five consecutive cases of closed fractures of leg presenting within six hours of injury were taken for measurement of anterior compartment pressure at the level of fracture and at 5 cm and 10 cm away from the fracture site, using the Whitesides'' infusion technique. A differential pressure of less than 30 mm Hg was taken as the criterion for diagnosis of compartment syndrome.Results:
Two patients (2.67%) developed acute compartment syndrome. The mean anterior compartment pressures were highest at the level of the fracture and went on decreasing as we went away from the fracture site, which was found to be statistically significant (P < 0.001).Conclusion:
Compartment pressure measurement is the most reliable and objective method for early diagnosis of compartment syndrome. Whitesides'' infusion technique is a relatively easy and inexpensive method to come to a diagnosis of compartment syndrome in a developing country like India. Differential pressure is more reliable than absolute pressure in predicting the development of an impending compartment syndrome. 相似文献46.
Kuo PC Shen YC Yang ML Wang SH Thang TD Dung NX Chiang PC Lee KH Lee EJ Wu TS 《Journal of natural products》2007,70(12):1906-1909
Cytotoxicity-guided phytochemical investigation of a methanolic extract of Croton tonkinensis afforded two new kaurane diterpenoids (1, 2) and 10 known ent-kaurane-type diterpenoids (3- 12). The structures of 1 and 2 were based on analysis of spectroscopic and mass spectral data. Compounds 3- 12 were identified by comparison of their spectroscopic and physical data with those reported in the literature. Selected compounds from this plant were examined for cytotoxic and anti-inflammatory activities. Compounds 4 and 9 showed the highest cytotoxic activity against the tested tumor cell lines. Compounds 3, 4, 6, 8, 9, and 11 had IC 50 values less than 5 microM and were more potent than the nonspecific NOS inhibitor L-NAME in inhibiting LPS-induced NO production. 相似文献
47.
48.
该文研究了胰岛素抵抗与非胰岛素依赖型(NIDDM)合并高血压的关系。该文测定了48例NIDDM患者(NIDDM合并高血压者16例,血压正常的NIDDM者32例)的OGTT和IRT,并计算了SINS/SGLU和胰岛素敏感性新指数。结果表明两级间各时相血糖无明显差异(P>0.05),但空腹及糖负荷后胰岛素值在NIDDM合并高血压组显著高于血压正常组(P<0.05)。两级SGLU无显著差异,但SINS和SINS/SGLU在高血压组显著高于NIDDM血压正常组(153.65±13.6比67.45±20.5.2.57±1.53比1.58±1.60,P均<0.05)。胰岛素敏感性新指数在正常人为1.0,NIDDM血压正常组为0.58,伴高血压组为0.38.该文认为胰岛素抵抗或高胰岛素血症可能是NIDDM合并高血压患者的主要病因之一,并讨论了其发生机制及防治措施。 相似文献
49.
Human immunodeficiency virus (HIV) infection patterns and risk behaviours in different population groups and provinces in Viet Nam 总被引:1,自引:0,他引:1
Tuan NA Fylkesnes K Thang BD Hien NT Long NT Kinh NV Thang PH Manh PD O'Farrell N 《Bulletin of the World Health Organization》2007,85(1):35-41
OBJECTIVE: To study patterns and determinants of HIV prevalence and risk-behaviour characteristics in different population groups in four border provinces of Viet Nam. METHODS: We surveyed four population groups during April-June 2002. We used stratified random-cluster sampling and collected data concomitantly on HIV status and risk behaviours. The groups included were female sex workers (n = 2023), injecting drug users (n = 1391), unmarried males aged 15-24 years (n = 1885) and different categories of mobile groups (n = 1923). FINDINGS: We found marked geographical contrasts in HIV prevalence, particularly among female sex workers (range 0-24%). The HIV prevalence among injecting drug users varied at high levels in all provinces (range 4-36%), whereas lower prevalences were found among both unmarried young men (range 0-1.3%) and mobile groups (range 0-2.5%). All groups reported sex with female sex workers. Less than 40% of the female sex workers had used condoms consistently. The strongest determinants of HIV infection among female sex workers were inconsistent condom use (adjusted odds ratio [OR], 5.3; 95% confidence interval [CI], 2.4-11.8), history of injecting drug use and mobility, and, among injecting drug users, sharing of injection equipment (adjusted OR, 7.3; 95% CI, 2.3-24.0) and sex with non-regular partners (adjusted OR 3.4; 95% CI 1.4-8.5). CONCLUSION: The finding of marked geographical variation in HIV prevalence underscores the value of understanding local contexts in the prevention of HIV infection. Although lacking support from data from all provinces, there would appear to be a potential for sex work to drive a self-sustaining heterosexual epidemic. That the close links to serious injecting drug use epidemics can have an accelerating effect in increasing the spread of HIV merits further study. 相似文献
50.
As CD8+CD28- T cells have been associated with dendritic and T cell suppression, we analyzed whether an increase in CD8+CD28- T cell numbers during HIV-1 infection could lead to impaired T cell responses. In contrast to the in-vitro generated CD8+CD28- suppressors, peripheral blood CD8+CD28- T cells of both HIV-infected and noninfected individuals promoted dendritic cell activation. The CD8+CD28- T cell accumulation during HIV-1 infection may thus contribute to accelerated inflammatory reactions and immune activation. 相似文献