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1.
ART技术封闭恒牙的3年临床效果观察   总被引:4,自引:1,他引:3  
目的 :评价非创伤性充填 (ART)技术对恒牙窝沟封闭后 ,封闭剂保留及新生龋病发生情况。方法 :1996年在四川省德阳市 4所中学选取 12~ 13岁儿童 14 0名作 191个ART封闭。采用WHO的ART标准器械 ,德国ESPE公司生产的高强度玻璃离子材料 ,对选择的牙面窝沟进行封闭 ;操作者为经中等口腔专业训练的医生。试验 3年后对ART封闭及牙龋病情况进行评价。结果 :封闭后 1、2、3年的封闭成功率分别为 89.6% ,78.8% ,71.9%。试验后 1年没有新生龋齿的发生 ,试验后 2、3年 ,龋患率较低 ,分别为 1.6% ,2 .8%。结论 :ART封闭试验 3年的保存率较高 ,新生龋发生率低 ;作为恒牙龋病防治的措施是适合和可接受的 ;是一种适合于在学校、社区开展的有效、实用的龋病预防方法。  相似文献   
2.
Stigma is a recognised problem for effective prevention, treatment, and care of HIV/AIDS. However, few studies have measured changes in the magnitude and character of stigma over time. This paper provides the first quantitative evaluation in Africa of the changing nature of stigma and the potential determinants of these changes. More specifically, it evaluates the dynamic relationship between stigma and (1) increased personal contact with people living with HIV/AIDS and (2) knowing people who died of AIDS. Panel survey data collected in Cape town 2003 and 2006 for 1074 young adults aged 14–22 years were used to evaluate changes in three distinct dimensions of stigma: behavioural intentions towards people living with HIV/AIDS; instrumental stigma; and symbolic stigma. Individual fixed effects regression models are used to evaluate factors that influence stigma over time. Each dimension of stigma increased in the population as a whole, and for all racial and gender sub-groups. Symbolic stigma increased the most, followed by instrumental stigma, while negative behavioural intentions showed a modest increase. Knowing someone who died of AIDS was significantly associated with an increase in instrumental stigma and symbolic stigma, while increased personal contact with people living with HIV/AIDS was not significantly associated with any changes in stigma. Despite interventions, such as public-sector provision of antiretroviral treatment (which some hoped would have reduced stigma), stigma increased among a sample highly targeted with HIV-prevention messages. These findings emphasise that changes in stigma are difficult to predict and thus important to monitor. They also indicate the imperative for renewed efforts to reduce stigma, perhaps through interventions to weaken the association between HIV/AIDS and death, to reduce fear of HIV/AIDS, and to recast HIV as a chronic manageable disease.  相似文献   
3.
BACKGROUND: Many male cancer survivors experience fertility problems due to antineoplastic treatment. We report the fertility outcome in 67 couples referred to assisted reproduction treatment (ART) because of male factor infertility due to cancer. METHODS: This was a retrospective study assessing the following parameters: diagnosis, cancer treatment, type of fertility treatment and type of sperm used, number of pregnancies and pregnancy outcome. RESULTS: Testicular cancer and lymphomas were the most prevalent diagnoses. Adjuvant treatment with chemo- and/or radiation therapy had been given to 90% of the men. Semen was cryopreserved in 82% of the men prior to treatment. Following antineoplastic treatment, 43% of the men had motile spermatozoa in the ejaculate, but 57% were azoospermic. A total of 151 ART cycles were performed [55 intra-uterine insemination (IUI), 82 ICSI and 14 ICSI-frozen embryo replacement (FER)]. The clinical pregnancy rate per cycle was 14.8% after IUI, 38.6% after ICSI and 25% after ICSI-FER. The corresponding delivery rates were 11.1, 30.5 and 21%. Cryopreserved semen was used in 58% of the pregnancies. The delivery rate per cycle was similar after use of fresh or cryopreserved spermatozoa. CONCLUSIONS: Male cancer survivors have a good chance of fathering a child by using either fresh ejaculated sperm or cryopreserved sperm.  相似文献   
4.
BACKGROUND: The purpose of this study was to determine the rate of spontaneous gestational sac loss during the first trimester in women achieving multiple pregnancies by ICSI. METHODS: A retrospective analysis was performed of 1448 consecutive multiple pregnancies conceived by ICSI. RESULTS: Of the cohort of 1448 pregnancies, twin gestations constituted 59.6% (864), triplets 30.2% (438) and quadruplets 10.0% (146). During the first trimester, 69 (4.7%) patients miscarried, while 179 (12.3%) continued their pregnancies and had fewer gestational sacs at the end of the first trimester than at the beginning. The overall loss rate of any gestational sac during the first trimester in these multiple pregnancies was 10.1%. There was a significant difference in the frequency of spontaneous reduction to twin or singleton pregnancies in the first trimester between women carrying triplets (11.7%) and those carrying quadruplets (3.5%) [P = 0.004; odds ratio (OR) 3.5; 95% confidence interval (CI) 1.3-9.1]. The frequency of gestational sac loss was significantly greater among women >35 years old (20.9%) than in women less than 35 years old (15.9%) (P = 0.03; OR 1.4; 95% CI 1.0-1.9). CONCLUSION: In multiple pregnancies there is a significant risk of spontaneous loss of any embryo during the first trimester. These findings should be considered prior to any decision about selective embryo reduction.  相似文献   
5.
BACKGROUND: Retrospective cohort study to evaluate differences in outcome when embryo transfer was performed either on day 2-3 (cleavage stage, CS-group) or on day 4-5 (blastocyst stage, BS-group). METHODS: A total of 1259 consecutive cycles yielding 500 live born babies performed at a single centre in Bregenz, Austria, were included. Main outcome measures were implantation and (multiple) pregnancy rates and neonatal outcome including birth defects. RESULTS: Total Pregnancy rate was 44% vs 28% (P < 0.001) and the total 'take home baby rate' was 37% vs 22% in the BS-group and the CS-group, respectively. Rate of multiple gestations (34% vs 17%, P = 0.001) was significantly higher among the BS-group, resulting in a higher rate of preterm deliveries < 36 weeks (26% vs 17%, P = 0.045). Female factor causing infertility (40% vs 21%, P < 0.001) was significantly higher among the BS-group. For the CS-group, rate of singleton pregnancies (83% vs 66%, P = 0.001) and idiopathic cause of infertility (34% vs 22%, P = 0.012) were significantly higher. No statistically significant differences were found in sex, Caesarean section rate, Apgar score and umbilical artery pH-values, total mean birth weight, admission rate to intensive care unit, days of hospitalization and number of minor and major birth defects. CONCLUSIONS: Our data suggest that blastocyst transfer may lead to a higher pregnancy rate with an overall better take-home baby rate (THBR) at the cost of higher rates of multiples and preterm deliveries.  相似文献   
6.
本研究提出一种用模糊ART神经网络进行心律失常分析的方法。确定用于描述QRS波群特征的若干属性 ,提取其特征 ,模糊化处理后作为神经网络的输入模式矢量。神经网络为三层结构 ,经过竞争学习 ,对QRS波群进行自动分类。分类结果用MIT -BIH数据库进行了检验 ,证明本方法非常有效 ,30min数据的分析时间小于 2s,满足实用要求  相似文献   
7.
Induction of oxidative stress during the sperm preparation process for assisted reproductive techniques (ART) in men can weaken sperm parameters. Vitamin E (VE) is considered a factor in boosting male fertility. This experimental study (in vitro) aimed to assess the impact of VE supplementation on sperm quality and lipid peroxidation during sperm sampling at different times. For this mention, semen samples were collected from 50 asthenoteratozoospermic men. Samples were divided into control and test groups for 2, 4 and 6 hr that the test group was incubated with VE (2 mM). In two groups, total motility, progressive motility and viability based on the WHO 2010 criteria were assessed. Moreover, malondialdehyde (MDA) levels were evaluated in each group. In the control group, total and progressive motility and sperm viability were decreased significantly after 2 hr; however, MDA levels were increased significantly after 6 hr. Also, in the test group, sperm parameters were increased significantly after 2 hr, and MDA levels were decreased significantly after 6 hr compared to the control group. In outcome, in vitro VE supplementation may protect spermatozoa from the adverse effect of oxidative stress during sperm preparation via preservation antioxidant processes in normal condition.  相似文献   
8.
目的探讨拮抗剂方案和长方案对超重多囊卵巢综合征(PCOS)患者助孕结局的影响。方法回顾性分析2013年1月1日至2017年11月30日于本生殖中心初次行体外受精/卵胞浆内单精子注射(IVF/ICSI)助孕的PCOS且超重(BMI≥24 kg/m2)的356例患者临床资料,根据促排卵方案不同分为拮抗剂方案组(n=226)和长方案组(n=130),比较两组患者的基本资料、促排卵情况和临床结局,分析两组患者的中重度卵巢过度刺激综合征(OHSS)发生率、优质胚胎率、一次移植妊娠结局和累积活产率的差异。结果基本资料中,两组患者的女方年龄、BMI、基础睾酮水平差异均无统计学意义(P>0.05);与长方案组比较,拮抗剂方案组患者的基础FSH水平[(6.42±1.63)U/L vs.(6.78±1.53)U/L]显著降低(P<0.05),而窦卵泡数[(32.55±11.06)个vs.(28.02±7.09)个]显著增多(P<0.05)。促排卵情况比较中,拮抗剂方案组患者的扳机日LH和P水平以及优质胚胎率(38.04%vs.32.26%)显著高于长方案组患者(P<0.05),但E2水平及获卵数无显著性差异(P>0.05)。在临床结局比较中,两种方案的中重度OHSS发生率、因OHSS高风险取消移植周期率、一次移植妊娠结局、乐观累积活产率以及保守累积活产率差异均无统计学意义。结论对于超重PCOS患者,与长方案相比,拮抗剂方案可获得更多的优质胚胎,但两种方案的临床结局相当。  相似文献   
9.
刘玮  程利南 《生殖与避孕》2003,23(6):375-378
辅助生殖技术(又称助孕技术)的发展在治疗不孕的同时导致多胎妊娠率的提高。本文阐述助孕技术与多胎妊娠的关系,以及如何通过严格控制超促排卵指征、控制移植胚胎数量、冻存胚胎、选择性单胚胎移植、减胎术的应用等方法来获得最佳妊娠率,同时降低助孕术后的多胎妊娠特别是三胎及三胎以上妊娠的发生。  相似文献   
10.
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