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91.
To examine the prevalence of Internet sex networking among men who have sex with men (MSM) in Hong Kong and risk behaviors associated with the behavior, a telephone survey of 15,230 Hong Kong Chinese men aged 18-60 was conducted. Of the 283 active MSM (having engaged in some MSM behaviors in the last 6 months) identified, 17.7% had networked for MSM partners via the Internet in the last 6 months. Younger age (odds ratio [OR] for age < or = 25 vs. age >25 = 4.67, 95% confidence interval [CI] = 2.35-9.28) and being an anal-sex MSM (OR = 4.72, 95% CI=2.36-9.44) were independent predictors of Internet sex networking. Being an Internet sex networker was associated with some risk behaviors such as having contracted a sexually transmitted disease (adjusted OR = 4.79, 95% CI = 1.34-17.11), having had > or = 3 MSM partners (adjusted OR = 4.74, 95% CI = 2.20-10.23), and having engaged in anal sex (adjusted OR = 3.95, 95% CI = 1.89-8.23). HIV prevention programs for MSM should thereby include Internet-based interventions.  相似文献   
92.
Tacrolimus combined with mycophenolate mofetil (MMF) is an effective regimen in kidney transplantation. This study compared the efficacy of combining tacrolimus and two different dosages of sirolimus with an established tacrolimus-MMF regimen. Each day in addition to tacrolimus, 325 patients received 2 mg sirolimus (TAC-SRL2 mg), 325 patients received 0.5 mg sirolimus (TAC-SRL0.5 mg) and 327 patients 1 g MMF (TAC-MMF). The initial tacrolimus dose was 0.2 mg/kg/day. Sirolimus patients received loading doses of 6 or 1.5 mg, and daily doses of 2 or 0.5 mg thereafter. Steroid administration was identical for all groups. The incidence of biopsy-proven acute rejection was lower in the TAC-SRL2 mg group (15.7%) compared with the TAC-SRL0.5 mg (25.2%, p = 0.003) and the TAC-MMF groups (22.3%, p = 0.036). Six-month graft survival was 91.0% (TAC-SRL2 mg), 92.6% (TAC-SRL0.5 mg) and 92.4% (TAC-MMF); the respective values for patient survival were 98.1%, 97.8% and 97.9%. Thirty-four patients (10.5%), 19 patients (5.8%) and 16 patients (4.9%) in the TAC-SRL2 mg, TAC-SRL0.5 mg and TAC-MMF groups, respectively, discontinued the study because of adverse events. Hyperlipemia was reported more often in the TAC-SRL2 mg group (24.0%) compared with 19.4% (TAC-SRL0.5 mg) and 11.0% (TAC-MMF; p < 0.05). Combining 2 mg sirolimus/day with tacrolimus results in lower rates of acute rejection, but a higher incidence of adverse events.  相似文献   
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Opportunistic infections in the oral cavity of the elderly may increase the incidence of systemic disease. The objective of this study was to investigate the differences in the oral bacterial flora between dependent elderly (inpatients) and independent elderly (community-dwelling residents). After multiple variables were taken into account, inpatients had significantly lower detection rates than community-dwelling residents for alpha-streptococci (p < 0.001) and Neisseria (p 0.004), and higher detection rates for Pseudomonas aeruginosa (p 0.024), methicillin-resistant Staphylococcus aureus (MRSA) (p 0.011) and Actinomyces spp. (p 0.005). Among inpatients, the requirement for a high degree of care was related negatively to detection of alpha-streptococci, but was related significantly to detection of P. aeruginosa (p 0.018) or MRSA (p 0.004). Tube-fed inpatients had a significantly lower detection rate for alpha-streptococci (p 0.041) and a higher detection rate for P. aeruginosa (p 0.004) than those who did not require tube feeding. Inpatients with a history of antibiotic use had a significantly lower detection rate for alpha-streptococci (p 0.049) and a higher detection rate for MRSA (p 0.007) than those without a history of antibiotic use. The detection rates for P. aeruginosa or MRSA in inpatients without alpha-streptococci were higher than in inpatients with alpha-streptococci after controlling for age and gender (P. aeruginosa, p 0.006; MRSA, p 0.001). Overall, detection of alpha-streptococci had an inverse correlation with the detection of P. aeruginosa and MRSA in the oral cavity and is likely to be an indicator of pathogenic bacterial infection.  相似文献   
99.
In order to assess the state and pathology of the woman's pelvis minor, a number of methods are commonly used among practitioners, encompassing clinical exploration, radiology, MRN, urodynamics, endoscopy and echography.

Echography has been poorly used in clinical pelvic exploration and its reliability is actually a matter of controversy 1. However, echographic surveys can provide us with valuable gynecological data on the state and pathologies of the soft pelvis, within the genital regions or even going beyond them, i.e. the rectal channel, bladder, urethra, anus, vascular plexuses, and all of their supporting tissues.

At our research unit, we have been employing Transvaginal Ultrasound echography (TVU) for a long time in conjunction with other pelvis-focused methods in order to study different kinds of pelvic alterations. TVU has proven to be friendly to use, fast, harmless and inexpensive, allowing serial explorations and producing high-quality dynamic images (loop-cinema, video-tape). Furthermore, this method is fairly aseptic in that the occurrence of faeces in the rectal ampolla is not a nuisance but a bonus in tracking the contours of the rectum walls and other topographical features which would be otherwise difficult to survey.

A complete pelvic floor TVU may add no longer than 5-8 minutes to a routine gynecological examination, can be implemented by the general gynecologist and generates data that can be further studied by the appropriate specialist for a more insightful evaluation 2.  相似文献   
100.
We reported on the unusually high isotope effect of non-aromatizing androgen 19-hydroxylase in sheep and dog adrenals and the validity of the [3H] water method using [19-3H3] androgen. We have extended the study to examine whether this 19-hydroxylation is catalyzed by a cytochrome P-450 dependent enzyme. Sheep adrenal homogenate (1.65 mg prot.) was incubated in the presence of NADPH (5.6mM) with [19-3H3, 4-14C]-androstenedione (A) (3.2 microM, 8.24 x 10(4) dpm 3H/micrograms, 3H/14C = 17.2) in a total of 1.2 ml PO4 buffer under air at pH 7.4 for 2, 5 and 10 min. [19-3H2, 4-14C]-19-hydroxy-A (19-OHA) with added carrier was purified through extraction, TLC, acetylation to form 19-AcOA, and further TLC to give 19-hydroxylase activity as assessed by the product isolation method. Simultaneously, the [3H] water was measured by distillation, and with correction by the apparent kinetic isotope effect (KH/KT = 11.8), used for assessment of 19-hydroxylase activity. The effects on the hydroxylation by cofactor (NADPH, NADH), incubation atmosphere (N2, CO/O2), cytochrome P-450 inhibitors (metyrapone, clotrimazole) and heating were measured by both methods. Compared to the complete system (89.6pmol/min/mg as 100%), carbon monoxide suppressed 15.8, 59.3 and 86.4% of the 19-hydroxylation when a CO/O2 ratio of 0.1, 1 and 9 was used, respectively. Replacement to nitrogen atmosphere decreased the activity by 93.8%. Replacement of NADPH with NADH (7.5mM) caused more than a 92.1% decrease in activity. Metyrapone at 50 and 200 microM and and clotrimazole at 2.5 and 10 microM suppressed the activity by 82.8, 90.4, 85.4 and 94.9%, respectively. A larger scale sheep adrenal incubation of A (250 microM) under 18O2 atmosphere and isolation of 19-AcOA were carried out in a similar manner. The gas chromatography-mass spectrometry analysis of the purified product showed 48.5% of the product to be 18O-labeled as [M+ + 2], m/e 346. Thus, the non-aromatizing androgen 19-hydroxylase requires NADPH and molecular oxygen. It is strongly inhibited by carbon monoxide and cytochrome P-450 inhibitors. These results indicate that the enzyme system responsible for non-aromatizing androgen 19-hydroxylase in adrenal is a cytochrome P-450 dependent monooxygenase.  相似文献   
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