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21.
Genital tract trauma is common following vaginal childbirth, and perineal pain is a frequent symptom reported by new mothers. The following techniques and care measures are associated with lower rates of obstetric lacerations and related pain following spontaneous vaginal birth: antenatal perineal massage for nulliparous women, upright or lateral positions for birth, avoidance of Valsalva pushing, delayed pushing with epidural analgesia, avoidance of episiotomy, controlled delivery of the baby's head, use of Dexon (U.S. Surgical; Norwalk, CT) or Vicryl (Ethicon, Inc., Somerville, NJ) suture material, the "Fleming method" for suturing lacerations, and oral or rectal ibuprofen for perineal pain relief after delivery. Further research is warranted to determine the role of prenatal pelvic floor (Kegel) exercises, general exercise, and body mass index in reducing obstetric trauma, and also the role of pelvic floor and general exercise in pelvic floor recovery after childbirth.  相似文献   
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A multicenter clinical study was conducted using iohexol, a second-generation nonionic contrast medium, for excretory urography performed in 130 children. Doses of iohexol (300 mg iodine/ml) ranged between 150 and 660 mgI/kg (0.5 and 2.2 ml/kg). Iohexol was tolerated well, and no significant adverse reactions occurred. Sixty-five iohexol urograms were evaluated to determine the minimum dose for adequate visualization of the kidneys and collecting systems. A dose greater than 300 mgI/kg (1.0 ml/kg) always resulted in a urogram of diagnostic quality, while visualization was insufficient for diagnosis in 10% of studies done with doses of 150-300 mgI/kg (0.5-1.0 ml/kg). Another 65 iohexol urograms were compared in a blinded manner with a similar number of studies performed using iothalamate meglumine at comparable iodine concentration and dose. Visualization of calyces and pelvoinfundibular structures achieved with iohexol was rated better with statistical significance, but there was no difference in visualization of the renal parenchyma or ureters. Use of iohexol in excretory urography may be advantageous in children who are at greatest risk for an adverse reaction to contrast media or in those most likely to benefit from use of a low osmolality contrast agent.  相似文献   
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The purpose of this study was to optimize monitoring methods and to investigate new technology for the determination of low levels of acrylonitrile (0.05 to 5 ppm) in workplace atmospheres. In the first phase of the study, a dynamic atmosphere generation system was developed to produce low levels of acrylonitrile in simulated workplace atmospheres. Various potential sorbents were investigated in the second phase, and the candidate methods were compared in a laboratory validation study over a concentration range from 0.05 to 5 ppm acrylonitrile in the presence of potential interferences and under relative humidity conditions from 30% to 95% RH. A collection tube containing 600 mg Pittsburgh coconut base charcoal was found to be the optimum tube for sampling for a full 8-hr shift. No breakthrough was observed over the concentrations and humidities tested. The recovery was 91.3% with a total relative precision of +/- 21% over the test range, and the recovery was not affected by storage for up to five weeks.  相似文献   
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组织工程细胞支架的免疫原性研究   总被引:1,自引:1,他引:1  
目的:以组织工程血管脱细胞支架和仿生髓核组织工程细胞支架、周围神经去细胞神经基膜管为例,介绍组织工程脱细胞支架的免疫原性研究情况. 方法:应用计算机检索Medline 1997-01/2007-03关于免疫原性的文章.检索词“Immunotoxicology”并限定文章的语种类为English.同时利用计算机检索中国期刊全文数据库1997-01/2007-03的相关文章,限定文章语言种类为中文,检索词“组织工程,免疫原性”. 结果:主要组织相容性复合体Ⅰ免疫组织化学方法能够检测血管脱细胞支架的免疫原性;组织学观察及反转录-聚合酶链反应检测γ-干扰素、白细胞介素2、白细胞介素4、白细胞介素10 mRNA表达,可以反映仿生髓核组织工程支架的免疫原性;主要组织相容性复合体Ⅱ抗原可以反映出经过化学萃取后的去细胞预变性神经基膜血管结构保留较完整,免疫原性低. 结论:脱细胞可以极大地降低组织工程支架的免疫原性,从而使得组织工程产品有更广阔的使用前景.  相似文献   
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BACKGROUND: Most blood centers utilize a confidential unit exclusion (CUE) process, intended to reduce the risk of transfusion-associated infectious diseases by allowing high-risk donors confidentially to exclude their blood from use for transfusion. The effectiveness of this method remains controversial. STUDY DESIGN AND METHODS: Confirmatory or supplemental test results for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus, as well as hepatitis B surface antigen and syphilis and screening test results for antibodies to hepatitis B core (antigen) and alanine aminotransferase levels were obtained for approximately 1.8 million units donated during 1991 and 1992 at five blood centers within the United States. The prevalences of these infectious disease markers in units that the donors confidentially excluded (CUE+) and units that the donors did not exclude (CUE-) were calculated and examined within demographic subgroups. RESULTS: Units that were CUE+ were 8 to 41 times more likely to be seropositive for antibodies to human immunodeficiency virus and hepatitis C virus, hepatitis B surface antigen, and syphilis and three to four times more likely to react for antibody to hepatitis B core (antigen) or to have elevated alanine aminotransferase levels than units that were CUE- (p < 0.001). The positive predictive value of CUE (the percentage of CUE+ units that were confirmed seropositive for any marker) was 3.5 percent, and the sensitivity of CUE (the percentage of confirmed-seropositive units that were CUE+) was 2.3 percent. CONCLUSION: The current CUE process has low sensitivity and apparently low positive predictive value, and in many cases, it appeared that donors misunderstood it. Yet, CUE was not a “random process,” as CUE+ units were more likely to be seropositive for any infectious disease marker than CUE- units. This suggests that efforts to improve the CUE system may be warranted. As risk factors for transfusion-transmitted infection become more difficult to identify by history-based screening, however, such efforts may have limited effect.  相似文献   
29.
Objective

Higher rates of adverse outcomes have been reported for early term (37 0 to 38 6 weeks) versus full term (≥?39 0 weeks) infants, but differences in breastfeeding outcomes have not been systematically evaluated. This study examined breastfeeding initiation and exclusivity in early and full term infants in a large US based sample.

Methods

This secondary analysis included 743 geographically- and racially-diverse women from the Measurement of Maternal Stress Study cohort, and 295 women from a quality assessment at a hospital-based clinic in Evanston, IL. Only subjects delivering?≥?37 weeks were included. Initiation of breastfeeding (IBF) and exclusive breastfeeding (EBF) were assessed via electronic medical record review after discharge. Associations of IBF and EBF with early and full term delivery were assessed via univariate and multivariate logistic regression.

Results

Among 872 women eligible for inclusion, 85.7% IBF and 44.0% EBF. Early term delivery was not associated with any difference in frequency of IBF (p?=?0.43), but was associated with significantly lower odds of EBF (unadjusted OR 0.61, 95% CI 0.466, 0.803, p?<?0.001). This association remained significant (adjusted OR 0.694, 95% CI 0.515, 0.935, p?=?0.016) after adjusting for maternal diabetes, hypertensive disorders of pregnancy, cesarean delivery, maternal age, race/ethnicity, parity, Medicaid status, NICU admission, current smoking, and delivery hospital.

Conclusions for Practice

Despite comparable breastfeeding initiation frequencies, early term infants were significantly less likely to be exclusively breastfed compared to full term infants. These data suggest that women with early term infants may benefit from counseling regarding the potential for breastfeeding difficulties as well as additional breastfeeding support after delivery.

  相似文献   
30.

Problem

A multinational company with operations in several African countries was committed to offer antiretroviral treatment to its employees and their dependants.

Approach

The Accelerating Access Initiative (AAI), an initiative of six pharmaceutical companies and five United Nations’ agencies, offered the possibility of obtaining brand antiretroviral drugs (ARVs) at 10% of the commercial price. PharmAccess, a foundation aimed at removing barriers to AIDS treatment in Africa, helped to establish an HIV policy and treatment guidelines, and a workplace programme was rolled out from September 2001.

Local setting

Private sector employers in Africa are keen to take more responsibility in HIV prevention and AIDS care. An important hurdle for African employers remains the price and availability of ARVs.

Relevant changes

The programme encountered various hurdles, among them the need for multiple contracts with multiple companies, complex importation procedures, taxes levied on ARVs, lack of support from pharmaceutical companies in importation and transportation, slow delivery of the drugs, lack of institutional memory in pharmaceutical companies and government policies excluding the company from access to ARVs under the AAI.

Lessons learned

The launch of the AAI enabled this multinational company to offer access to ARVs to its employees and dependants. The private sector should have access to these discounted drugs under the AAI. A network of local AAI offices should be created to assist in logistics of drugs ordering, purchase and clearance. No taxes should be levied on ARVs.  相似文献   
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