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Although the influence of the menstrual cycle on both vaginal candidosis and Candida albicans adherence to vaginal epithelial cells in vitro has been shown to be significant, similar studies have not been made on oral candidosis and adherence to buccal epithelial cells. The aim of this study was therefore to use an in vitro adherence assay to investigate the possible influence of the menstrual cycle on the adherence of C. albicans to buccal epithelial cells. Epithelial cells were collected from a single, healthy, female volunteer on days 5, 15, 22 and 28 of six menstrual cycles. Adherence of C. albicans was significantly higher to buccal epithelial cells collected on day 5 of the menstrual cycle when compared with days 15, 22 and 28, both in terms of the percentage of buccal epithelial cells with adherent C. albicans and the number of C. albicans adhering per 200 buccal epithelial cells in four out of six menstrual cycles (p < 0.001). This result indicates that hormonal influences should be considered when buccal epithelial cells are used in vitro to assess candidal adherence and may implicate hormonal factors in the aetiology of oral candidosis.  相似文献   
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BACKGROUND: The efficacy of breast self-examination in helping to reduce mortality from breast cancer has not been rigorously demonstrated. PURPOSE: To assess efficacy, a large, randomized trial was initiated in Shanghai, China. METHODS: From October 1989 to October 1991, 267040 current and retired female employees associated with 520 factories in the Shanghai Textile Industry Bureau were randomly assigned on the basis of factory to either a self-examination instruction group (133375 women) or a control group (133665 women). The women were born within the period from 1925 through 1958. Women in the instruction group were given intensive training in breast self-examination, including the use of silicone breast models and personalized instruction, plus two subsequent reinforcement sessions and multiple reminders to practice the technique. Women in the control group were asked to attend training sessions on the prevention of low back pain. All women have been followed for the development of breast diseases and for death from breast cancer. RESULTS: A high level of participation during the first 4-5 years of the trial was documented among women in the instruction group. Randomly sampled women in this group demonstrated greater proficiency in detecting lumps in breast models than did randomly sampled women in the control group. Approximately equal numbers of breast cancers were detected in the two groups (331 in the instruction group and 322 in the control group) through 1994, which is the last year for which case-finding efforts have been completed. The breast cancers detected in the instruction group were not diagnosed at an appreciably earlier stage or smaller size than those in the control group. More benign breast lesions were detected in the instruction group than in the control group (1457 versus 623, respectively), suggesting a higher index of suspicion for women who received training. Cumulative breast cancer mortality rates through 5 years from entry into the study were nearly equivalent for the two groups. CONCLUSIONS: Breast self-examination has not led to a reduction in mortality from breast cancer in this study cohort in the first several years since the trial began. A shift toward the diagnosis of disease at a less advanced stage in women given instruction has also not been demonstrated. Longer follow-up of participants in this trial is required before final assessment can be made of the efficacy of breast self-examination. IMPLICATIONS: At this time, there is insufficient evidence to recommend for or against the teaching of breast self-examination.  相似文献   
34.
BACKGROUND: Significant morbidity and mortality are associated with falls in older adults. We tested the hypothesis that older women with a history of falls demonstrate decreased muscle endurance and longer recovery times following fatiguing exercise. METHODS: We evaluated dynamic endurance and recoverability of the quadriceps femoris of 29 young women (YW) (M age = 21.7), 26 older women with a history of falls (FA) (M age = 73.3), and 27 older women with no history of falls (NF) (M age = 71.2) using an isokinetic dynamometer. Subjects performed repeated maximal concentric knee extensions until the force output of two consecutive repetitions fell below 50% of their maximal voluntary contraction (MVC). Recovery was defined as the time required for the return of force output > or = 80% MVC for 2 consecutive repetitions, within a set consisting of 3 maximal contractions. One minute rest was allowed between sets. We collected electromyographic (EMG) data from the quadriceps during all testing to evaluate spectral shifts. RESULTS: ANOVA with a post-hoc Bonferroni-Dunn test revealed time to fatigue was significantly faster in FA than YW (p < .02) and in FA than NF (p < .05), but not different between YW and NF. Time to recovery was significantly slower in FA than YW (p = .01), but not different between YW and NF, or between FA and NF, EMG median frequency power shift (from the beginning to the end of the test) was significantly less in FA (p < .001) than either YW (p < .002) or NF (p < .05). CONCLUSIONS: Older women with a history of falls demonstrate decreased muscular endurance compared to YW and NF, and increased time to recover from fatiguing exercise when compared to young women.  相似文献   
35.
BACKGROUND: The efficacy of antiresorptive therapy in preventing fractures in women at highest fracture risk, such as very elderly women or those with severe osteoporosis, is uncertain. PARTICIPANTS AND METHODS: Using data from a double-blind, randomized, placebo-controlled clinical trial that enrolled 2027 postmenopausal women aged 55 to 81 years with low femoral neck bone mineral density (BMD) and existing vertebral fractures, we examined the consistency of the effect of treatment with alendronate sodium in preventing fractures within a priori-specified risk subgroups defined at baseline by age, bone density, number of preexisting vertebral fractures, and history of postmenopausal fracture. The women were randomized to oral administration of alendronate or placebo and followed up for an average of 2.9 years. The initial dose of alendronate sodium was 5 mg/d; the dosage was increased from 5 to 10 mg/d at 24 months. New vertebral fractures, the primary end point of this arm of the trial, were defined by morphometry as a decrease of 20% and at least 4 mm in any vertebral height between baseline and a follow-up radiograph at 36 months. Incident clinical fractures, the secondary end point, included nonspine and clinical (symptomatic) vertebral fractures. All clinical fractures were confirmed with x-ray film reports or, in the case of clinical vertebral fractures, x-ray films. RESULTS: Overall, there was a 47% significant reduction in risk of new vertebral fractures in the alendronate group compared with the placebo group. The reduction in risk of new vertebral fracture was consistent across fracture risk categories including age (relative risk [RR], 0.49 in women < 75 years compared with 0.62 in those > or = 75 years), BMD (RR, 0.54 in women with a femoral neck BMD < 0.59 g/cm2 [median] compared with 0.53 in those with a BMD > or = 0.59 g/cm2), and number of preexisting vertebral fractures (RR, 0.58 in women with 1 vertebral fracture compared with 0.52 in those with > or = 2). The overall significant 28% reduction in risk of incident clinical fractures in the alendronate group compared with the placebo group was also observed within these subgroups. Compared with the number of lower-risk women, a similar or smaller number of high-risk women needed to be treated to prevent 1 fracture. For example, 8 women aged 75 years or older compared with 9 women younger than 75 years, or 4 women with 2 or more existing vertebral fractures compared with 16 women with 1 existing vertebral fracture, needed to be treated with alendronate for 5 years to prevent 1 new vertebral fracture. CONCLUSIONS: Alendronate effectively reduces fracture risk in postmenopausal women with vertebral fractures and low BMD, including those women at highest risk because of advanced age or severe osteoporosis. Since the risk reductions observed with alendronate treatment were consistent within fracture risk categories, more fractures were prevented by treating women at highest risk.  相似文献   
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37.
从模式I2C总线接口电路设计及其VLSI实现   总被引:3,自引:0,他引:3  
陈安  唐长文  闵昊 《微电子学》2002,32(3):185-188
提出了一种从模式的I^2C总线接口电路,该接口电路实现了对可变参数ASIC芯片的配置。该电路的设计使得可配置的ASIC芯片中参数配置所需要的芯片管脚大大减少。该方案已通过行为仿真和综合后门级时序仿真,并且用无锡上华0.6μmCMOS工艺实现。  相似文献   
38.
前言银和其他贵金属元素一样,在地壳中比较稀少,按其自然丰度为第67号元素,平均含量仅0.07 ppm。由于地质样品成分非常复杂,为测定其微量银,必须进行严格的化学分离。但是迄今文献中报道的许多分离分法,步骤都相当冗长,一般采用氯化银反  相似文献   
39.
Laparoscopic cholecystectomy is the treatment of choice for symptomatic cholelithiasis. Since its introduction in 1987, this procedure has been employed with increasing frequency as its safety has been documented in numerous studies. Absolute contraindications to laparoscopic cholecystectomy have become relative contraindications, and patients previously felt to be at excessive risk for laparoscopic cholecystectomy are viewed as patients who may benefit from laparoscopic cholecystectomy. The use of this procedure in patients with comorbid medical conditions has the potential to decrease patient morbidity. Patients who have previously undergone solid organ transplantation and require immunosuppressive therapy are a group of patients who may benefit from laparoscopic cholecystectomy. We report four patients who have previously undergone combined renal and pancreas transplantation who underwent successful laparoscopic cholecystectomy.  相似文献   
40.
采用2 2 2级联全差分结构和低电压、高线性度的电路设计实现了高动态范围、低过采样率的ΣΔ调制器.在1.8V工作电压,4 MHz采样频率以及80 k Hz输入信号的条件下,该调制器能够达到81d B的动态范围,功耗仅为5 m W.结果表明此结构及电路设计可以用于在低电压工作环境的高精度模数转换中  相似文献   
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