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61.
We conducted an observational cohort study in three nurse-midwifery services to identify patient characteristics and clinical care measures related to perineal trauma at birth. Data were collected on all women who began care with a nurse-midwife in labor, using an adaptation of the Nurse-Midwifery Clinical Data Set (n = 3,049). Study variables included demographics, perineal management techniques and position for birth, and other intrapartum care and events. Univariate and multivariate analyses showed that episiotomy was strongly related to fetal bradycardia, prolonged second stage, ethnic status, and maternal education level. Warm compresses and flexion/counterpressure to slow delivery were protective. Spontaneous lacerations were influenced by these factors as well. The lateral position for birth was protective, and use of oils or lubricants and the lithotomy position increased lacerations. Multisite studies in nurse-midwifery practices may provide an ideal means of determining effective care measures in healthy populations.  相似文献   
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63.
OBJECTIVE: Our purpose was to determine whether the incidence of postoperative endometritis and wound infection is associated with the method of placental removal at the time of cesarean section.STUDY DESIGN: Parturients undergoing cesarean delivery were prospectively randomized to have the placenta removed manually or spontaneously. Patients were excluded from participation if they had received intrapartum prophylactic antibiotics or had been determined to have chorioamnionitis. After delivery of the infant women in the manual group had the placenta extracted by the primary surgeon, whereas women in the spontaneous group had the placenta delivered by gentle traction on the umbilical cord. All study subjects received perioperative prophylactic antibiotics. The primary outcome variable was a postcesarean infection, defined as postcesarean endometritis or wound cellulitis requiring drainage and antibiotic therapy.RESULTS: A total of 333 women were enrolled in the investigation, with 165 assigned to the manual removal group and 168 allocated to have spontaneous removal. There were no statistically significant differences in mean gestational age, frequency or duration of ruptured membranes, frequency or duration of labor, or mean number of vaginal examinations between the two study groups. Postoperative infections occurred in 25 of 168 (15%) women in the spontaneous delivery group compared with 44 of 165 (27%) women in which the placenta was manually extracted (relative risk 0.6, 95% confidence interval 0.4 to 0.9, p = 0.01). Subset analysis of patients delivered with ruptured membranes similarly demonstrated a statistically significant reduction in the incidence of postoperative infections with spontaneous placental removal compared with manual extraction (20% vs. 38%, relative risk 0.5, 95% confidence interval 0.3 to 0.9, p = 0.02). There was a similar trend toward a reduction in postdelivery infections associated with spontaneous placental removal in women with intact membranes; however, this difference did not attain statistical significance.CONCLUSIONS: Spontaneous delivery of the placenta after cesarean delivery is associated with a decrease in the incidence of postcesarean infections. (Am J Obstet Gynecol 1997;176:1250-4.)  相似文献   
64.
Summary The glycosphingolipid galactosylceramide (GalCer) has been identified as an alternate receptor for the human immunodeficiency virus type 1 (HIV-1). Here we review a liposome flotation assay used to study the interaction of the HIV-1 envelope glycoprotein (env) with artificial membrane vesicles containing GalCer. The properties of binding, the nature of the env binding site for GalCer, and the implications of this interaction for HIV-1 infection are discussed.  相似文献   
65.
A model for training the trainers of child care providers that employs Vygotsky's framework of the Zone of Proximal Development is described. This efficient training mechanism proposes mentoring relationships as a means to meet the developmental needs of experienced child care professionals and improve the quality of existing child care programs.The authors would like to thank Dr. Bille Thomas and the satellite resource center directors and staff members for their work on the project.  相似文献   
66.
Clinical findings and common symptoms in retinitis pigmentosa   总被引:3,自引:0,他引:3  
Data analysis was performed in a prospective study of clinical symptoms and findings in 500 patients with retinitis pigmentosa. The symptoms and findings in these patients met the usual definitions of the disease. At initial examination the patients were questioned in a standardized manner; symptoms and associated health problems were reviewed. Some patients were unable to answer all of the questions. Of the patients 274 (55%) were men and 226 (45%) were women, with a race distribution of 21 (4%) black, 47 (9%) Hispanic, 26 (5%) Oriental, three (1%) American Indian, and 403 (81%) white. Sixty-nine patients reported no symptoms of night blindness and 116 patients claimed no visual field changes; 90 stated that they saw better at dusk. The most common problem noted by 263 (53.3%) was headaches, 31 on a daily basis, 42 at least weekly, 124 infrequently, and the remainder nonspecifically. Numbness or tingling, mainly in extremities, was reported by 99 patients. The second most common problem affecting 170 patients (34.6%) was light flashes; since eight patients had retinal detachments, light flashes cannot be totally discounted. Of 143 patients who had been pregnant, 14 had visual changes.  相似文献   
67.
This double-blind study compared ampicillin-sulbactam 3 g versus cefoxitin 2 g in 136 adult patients at risk for developing an infection after abdominal surgery. Separate randomization schedules were used for colorectal, upper gastrointestinal/biliary, and other abdominal procedures. Study antibiotics were administered within 30 minutes before incision and repeated 6 hours later. Patients having colorectal surgery received a third dose of antibiotic 6 hours after the second. Efficacy evaluations were made on 123 patients, 62 in the ampicillin-sulbactam group and 61 in the cefoxitin group. The overall postoperative infection rates were 12.9% for ampicillin-sulbactam and 9.8% for cefoxitin (p>0.05); one wound infection occurred in each group. Adverse events were experienced by 13.2% of the ampicillin-sulbactam and 19.1% of the cefoxitin recipients (p>0.05). Cost-minimization analysis revealed that ampicillin-sulbactam was a cost-effective alternative to cefoxitin for the prevention of infection after abdominal surgery.  相似文献   
68.
We describe a tarsorrhaphy technique whereby an ipsilateral upper-eyelid tarsal pillar is sutured to a corresponding lower-eyelid recipient site. This technique allows maintenance of a narrowed interpalpebral fissure indefinitely, yet is easy to reverse without incurring lid-margin damage. Additionally, the procedure can be adjusted postoperatively to either narrow or widen the initial surgical result. We report our combined surgical experience in 35 consecutive procedures using this technique to treat eyes with exposure-related keratopathy of varied etiology, including facial nerve palsies, combined facial nerve palsy and trigeminal neuropathy with an anesthetic cornea, Graves' disease, congenital craniofacial anomalies, and severe keratitis sicca syndrome. The procedure was successful in improving exposure keratopathy symptoms in all 35 cases. Complications, reflecting the authors' learning curve with this new procedure, included intermarginal pyogenic granulomas, stretching of the tarsal pillar, minor lower-eyelid-margin eversion, and tarsal pillar dehiscence.  相似文献   
69.
Marijuana, and specifically its psychoactive component, THC, can up or down regulate lymphocyte proliferation in murine spleen cells depending in part on the method used to stimulate the cells. This study identifies a difference in THC induced disregulation using cells derived from two different secondary lymphoid organs, the spleen and the lymph node. It was found that THC treatment of mitogen (concanavalin A or phytohemagglutinin) stimulated cells derived from either organ resulted in suppression of the proliferative response. In contrast, spleen cells stimulated with anti-CD3 antibody and treated with low doses of THC displayed an enhanced proliferation whereas the response in lymph nodes did not change. The cell type involved with this THC immunoenhancement in spleen cells was found to be the Ly2 cell. Further differences in the THC modulation of Ly2 spleen cells as compared to lymph node cells were noted following stimulation with PHA. Proliferation of Ly2 cells of splenic origin was inhibited with low doses of THC whereas the Ly2 cells of lymph node origin were more resistant to this drug induced suppression. This study, therefore, demonstrates differences in the immunomodulatory capability of THC dependent upon the organ source of the lymphocytes.  相似文献   
70.
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