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91.
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Objective  To evaluate the repair techniques of continuous and interrupted methods for episiotomy or perineal tears.
Design  A randomised controlled trial.
Setting  The Hospital Universitario Principe de Asturias, a state hospital belonging to the community of Madrid.
Sample  Four hundred forty-five women who had undergone vaginal deliveries with episiotomies or second-grade tearing of the perineum between September 2005 and July 2007.
Methods  One group was repaired with continuous, nonlocking sutures involving the vagina, perineum, and subcutaneous tissues. The other group had continuous, locking sutures of the vagina, interrupted sutures in the perineal muscles, and interrupted transcutaneous sutures. The threads used for stitching were identical in both groups.
Main outcome measures  The participants were questioned regarding the sensation of pain and the use of painkillers on the second and the tenth days, and 3 months postpartum.
Results  When comparing the group with continuous suture to the group with interrupted sutures, the differences included less repair time (1 minute; P = 0.017) and less suture material used (relative risk [RR], 3.2, 95% CI: 2.6–4.0). The comparison of pain on the second and tenth days, and 3 months postpartum were not statistically different between the two techniques (RR, 1.08, 95% CI: 0.74–1.57; RR, 0.96, 95% CI: 0.59–1.55; and RR, 0.68, 95% CI: 0.19–2.46, respectively).
Conclusions  Although we did not demonstrate that one technique was better than the other in the incidence of pain in the short or long term, we showed that episiotomy and perineal tear repairs with continuous suturing were quicker and used less suture material without an increase in complication than interrupted suturing.  相似文献   
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Giving the rear wheels of manually propelled wheelchairs negative camber (by angling them such that the bottoms of the wheels are farther apart than the tops) has become increasingly popular, especially among active users. This study's purpose was to evaluate how changing camber affects a wheelchair's mechanics and the extent of these changes. Using a representative wheelchair occupied by an anthropomorphic dummy, we altered the camber from +15° to ?15° and measured the effects on nine selected variables. In addition to increasing the wheelchair's track width, negative camber increases the wheelchair's wheelbase and decreases the height of the frame. With negative camber, the center of gravity (CG) of the occupied wheelchair moves backwards. Negative camber causes a backwards tilt of the frame which, in turn, causes toe-out of the rear wheels, a positive caster-inclination angle and an increase in the caster-trail distance. It is apparent that a change in one component of a wheelchair can affect many others, which should be taken into consideration and, where appropriate, compensated for when changing the camber of the wheelchair.  相似文献   
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[目的]评估北京市社区妇女人乳头瘤病毒(HPV)的感染率;调查社区人群对HPV的认知情况以及对HPV疫苗接种的态度。[方法]采用横断面调查方法,对北京市展览路社区15 ̄54岁女性进行HPV认知和流行病学问卷调查,并留取了宫颈脱落细胞或会阴部标本进行HPV DNA检测。[结果]1013名女性接受了问卷调查,832例HPV DNA检测结果纳入了统计学分析。HPV总检出率为15.38%,高、低危型HPV感染率分别为13.34%和3.25%,同时感染高、低危型HPV的检出率为1.20%。1013名调查对象中有30.7%听说过HPV,其中51.78%知道HPV感染与宫颈癌有关;HPV的知晓率与年龄和教育程度有关(P〈0.05);经过简单宣教后,75.91%愿意接种HPV疫苗。[结论]北京市社区妇女HPV现患率较高,对HPV的知晓率也较高。开展公众健康教育,提高人群的认识水平是疫苗计划获得成功的关键因素。  相似文献   
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Objective: To determine the immunity to hepatitis B, poliomyelitis and measles in fully vaccinated Aboriginal and Torres Strait Island children in north Queensland.
Methodology: A cross-sectional survey of immunity in a sample of children; 101 fully vaccinated Aboriginal and Torres Strait Island children, with a median age of 24.5 months, from 10 communities in North Queensland participated in this study. The main outcome measures were the prevalence of adequate antibody levels against hepatitis B, poliomyelitis and measles.
Results: Only 54% (95% Cl 44–63%) of the children had adequate immunity (10 m iu/mL) to hepatitis B, and one child had been infected despite vaccination. Although all the children (95% Cl 96–100%) had adequate immunity (i.e. neutralizing antibodies at a dilution of 1:8) to poliovirus 2, only 93% (95% Cl 86–96%) and 60% (95% Cl 50–69%) had adequate immunity to polioviruses 1 and 3, respectively. Nearly all (96%; 95% Cl 90–98%) of the children had adequate immunity (i.e. detectable IgG antibody) to measles.
Conclusions: Although a relatively low proportion of the children had adequate antibody levels against hepatitis B the clinical significance of this observation is uncertain. Further studies are needed to determine whether fully vaccinated Torres Strait Island children have been adequately protected and whether they require a booster dose of hepatitis B vaccine. A substantial proportion of fully vaccinated Aboriginal and Torres Strait Island children are inadequately protected against poliomyelitis, and therefore any such child with acute flaccid paralysis should be investigated fully for poliomyelitis. Vaccinated Aboriginal and Torres Strait Island children are well protected against measles, as are other Australian children.  相似文献   
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CASE REPORT: We present a case of traumatic displacement of corneal flap in the superior temporal quadrant 13 days after LASIK. The flap was repositioned after gentle irrigation of BSS, cleaned the interface and then drying the flap to verify its stability. In the next day the flap was adhered, clear cornea,smooth and visual acuity without correction was 1.00. DISCUSSION: We should try immediately to reposition the flap after traumatic displacement, as in this case.  相似文献   
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