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21.
The interactions among psychosocial and environmental stressors and the hypothalamus-pituitary-adrenal-ovarian-immune axes may provide a framework for examining altered sleep-wake patterns in women. Based on this biobehavioral framework, homeless women represent a subgroup of the female population who have many lifestyle factors that might make them vulnerable to sleep disturbances. This article presents a study designed to investigate the self-reported sleep patterns and lifestyle factors associated with the sleep of 50 homeless women, 18-44 years of age, residing in the downtown area of Los Angeles. Results indicated that almost half of the women slept six or less hours a day and had a day/night sleep pattern. A majority of the women reported restless sleep. Drinking beer, using cocaine, anxiety, depression, loneliness, and concerns about safety and money were factors significantly related to altered sleep patterns.  相似文献   
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OBJECTIVE: To determine the separate effects of maternal HIV infection and drug use during pregnancy on growth of uninfected children in their first 3 years. DESIGN: Retrospective analysis of measurements from health visitor records made during routine child health surveillance at 6 weeks, 10 months, and 3 years of age. Multilevel analysis allowed for between-infant variation in fitted growth lines, and adjustment for other factors. Growth was described in terms of an intercept (z score at term) and growth slopes (change in z score per year) up to, and from, 4 months. SUBJECTS: 290 case babies delivered in Edinburgh hospitals to women who reported injection drug use by either themselves or their HIV infected partner, and 186 community controls. A total of 131 (45%) of the case babies were born to women who used drugs, predominantly opiates, during pregnancy and 93 (32%) to HIV infected women. The eight infected children were excluded from analysis. MAIN OUTCOME MEASURES: Age and sex standardised z scores for height, weight, and body mass index. RESULTS: 459 (96%) of the 476 records for cases and controls were traced, yielding 1432 weight and 939 height measurements. Maternal HIV infection was not found to affect growth; at 3 years the estimated effect on weight z score was 0.16 with 95% confidence interval (-0.25 to 0.57) and for height 0.18 (-0.19 to 0.55). Drug use during pregnancy was associated with lighter babies at 40 weeks followed by depressed growth in the first four months, these infants remaining just slightly smaller at 3 years with an estimated effect on z scores of -0.5 for weight with 95% confidence interval (-0.89 to -0.11) and -0.37 (-0.72 to -0.02) for height. CONCLUSIONS: Maternal HIV infection does not adversely affect growth in uninfected infants, and the effect of drug use during pregnancy is limited to small decrease in size at 3 years.  相似文献   
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Angiotensin II (AngII) contributes to the maintenance of extracellular fluid volume by regulating sodium transport in the nephron. In nonepithelial cells, activation of phospholipase C (PLC) by AT-1 receptors stimulates the generation of 1,4,5-trisphosphate (IP(3)) and the release of intracellular calcium. Calcineurin, a serine-threonine phosphatase, is activated by calcium and calmodulin, and both PLC and calcineurin have been linked to sodium transport in the proximal tubule. An examination of whether AngII activates calcineurin in a model of proximal tubule epithelia (LLC-PK1 cells) was performed; AngII increased calcineurin activity within 30 s. An examination of whether AngII activates PLC in proximal tubule epithelia was also performed after first showing that all three families of PLC isoforms are present in LLC-PK1 cells. Application of AngII increased IP(3) generation by 60% within 15 s, which coincided with AngII-induced tyrosine phosphorylation of the PLC-gamma1 isoform also observed at 15 s. AngII-induced tyrosine phosphorylation was blocked by the AT-1 receptor antagonist, Losartan. Subsequently, an inhibitor of tyrosine phosphorylation blocked the AngII-induced activation of calcineurin, as did coincubation with an inhibitor of PLC activity and with an antagonist of the AT-1 receptor. It is therefore concluded that AngII stimulates calcineurin phosphatase activity in proximal tubule epithelial cells through a mechanism involving AT-1 receptor-mediated tyrosine phosphorylation of the PLC isoform.  相似文献   
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The study reviewed in this article evaluated a group of patients who underwent surgical therapy for calcaneal fractures at a Level I trauma center. One group of patients was treated after outpatient referral to the center, whereas the other group was admitted to, and underwent surgery at, the center. This study attempted to determine which patient risk factors or injury characteristics might lead to an increased rate of wound-healing complications. Bohler's angle is a classic radiographic method of determining the severity of calcaneal injury in this group of patients. The question posed by the authors of this study was: Does a drastic correction in Bohler's angle lead to an increased incidence of wound-healing complications? The authors do not recommend undercorrection of Bohler's angle but urge avoidance of overcorrection and stress the importance of early surgical fixation after lateral skin wrinkling is found.  相似文献   
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To gain information about patients who continue antiplatelet therapy while having cataract surgery, we performed a prospective, nonrandomized study. Twenty-four of 60 phacoemulsification procedures were performed on patients who were receiving medications with antiplatelet activity prior to surgery and who continued to receive the medications for the duration of the study. The remaining 36 procedures were performed on patients who received no medications with antiplatelet activity prior to surgery. One patient in the antiplatelet therapy group had a limited peribulbar hemorrhage, and one patient not receiving antiplatelet therapy had a postoperative hyphema. Postoperative subconjunctival hemorrhages were more common in the antiplatelet therapy group (P = .001). No patient in the antiplatelet therapy group had late postoperative complications. No differences in postoperative visual acuity or intraocular pressure were observed between the groups. Our results demonstrate that phacoemulsification and posterior chamber intraocular lens implantation can be performed without serious complications in some patients who continue to use antiplatelet therapy. However, our sample sizes were too small to determine whether such therapy is associated with any increased risk of rare but serious hemorrhagic complications.  相似文献   
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Introduction The standard treatment for patients who require total hip replacement is the implantation of an intramedullary diaphyseal anchored hip prosthesis. A bone-sparing thrust plate hip prosthesis (TPP) can be used as an alternative device for young patients. The TPP relies on proximal femoral metaphyseal fixation. The theoretical advantage of leaving diaphyseal bone intact is easier conversion to a stemmed prosthesis. This retrospective study evaluated the medium- and short-term results after total joint replacement using the third generation TPP.Materials and methods Between 1997 and 2001, 58 TPPs were used for 52 patients. Clinical and demographic data were obtained from the patients charts and our electronic database. Their average age at time of surgery was 40.9±11.4 years. At follow-up, the Harris hip score, residual pain, required pain medication, and the ability to lie on the operated side were documented. Radiographic evaluation included standardized radiographs of the hip joint and the pelvis.Results Four patients required revision surgery (6.9%). For 51 of the remaining 54 TPPs, a postoperative functional and radiological status was obtained. The average follow-up was 26±11.0 months. 88% of the patients experienced some or complete relief of pain. The median Harris hip score at follow-up was 73±20.5 points. A postoperative hip dislocation occurred in 5 patients (8.6%).Conclusion Since many patients experienced some or complete relief of pain, the TPP can be recommended as a feasible implant for the treatment of hip disorders requiring total hip arthroplasty in young patients. Revision surgeries are facilitated by the good bone stock remaining in the proximal femur.  相似文献   
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