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61.
C Yimin Y Wei C Weidong W Xianmi W Junqing L Lin 《International journal of gynaecology and obstetrics》2004,84(3):229-235
OBJECTIVES: To assess the effect of a medically induced abortion (MA) on birth weight in the first subsequent pregnancy. METHODS: Pregnant women who had had a MA, a surgical abortion (SA), or primigravidas with no history of abortion (NA), were recruited for a prospective cohort study between July 1998 and February 2001. The sample for the present analysis included 12995 singleton live births at term. RESULTS: The overall incidence rate of low birth weight (LBW) was 1.0%. The rates of LBW in the MA, SA, and NA groups were 1.0%, 0.9%, and 1.2, respectively. There were no significant differences in LBW rates between the MA and SA groups, neither between the MA and NA. Logistic regression analysis was used to estimate the effects of MA on birth weight, and we found no relationship between risk of LBW and MA. CONCLUSIONS: We did not find a statistically significant relationship between a history of one medically induced abortion and LBW for the first subsequent term pregnancy. 相似文献
62.
Matilde Valencia-Flores David N. Velázquez-Martínez Julían E. Villarreal 《Psychopharmacology》1990,102(1):136-144
The chronic exposure of rats to a schedule of operant water reinforcement coupled with chronically restricted access to water sensitized the animals to intermittentd-amphetamine injections (0.31–2.5 mg/kg with intervals of 12–23 days between any two injections) in such a way that this drug came to produce catastrophic losses of body weight (32.4% of control levels). In the sessions whend-amphetamine was administered, the rats were also given a total of 12 brief electric shocks. Loss of body weight was unaccompanied by parallel changes in operant behavior performance, or in food or water intake. Remarkably, in other studies with the same interventions (sham schedule sessions, water deprivation, and foot shocks), with the exception that reinforcers were never delivered,d-amphetamine did not produce catastrophic falls in body weight. This super-reactivity tod-amphetamine toxicity may be mediated by a possible stressor action of the schedule of reinforcement. Its mechanism might be analogous to the known sensitization produced by classical experimental stressor stimuli to the repeated administration ofd-amphetamine. 相似文献
63.
在营养调查的基础上,以975名北方籍和921名南方籍青年为代表,以实测身高体重为依据,分别推出了理想体重计算公式。北方理想体重(kg)=[身高(cm)-150]×0.6+50;南方理想体重(kg)=[身高(cm)-150]×0.6+48。为检验样本的代表性,又另取北方籍783名青年和南方籍883名青年进行了验证,结果表明,推出的计算公式有较好的代表性。用推出的计算公式分别对1464名北方青年和2264名南方青年的身高体重进行分析,结果表明,新推出的计算公式比以往的计算公式更符合我国的情况,因而更具有实用意义。 相似文献
64.
Outcome Following Bariatric Surgery in Super versus Morbidly Obese Patients: Does Weight Matter? 总被引:4,自引:2,他引:2
Mark Bloomston MD Emmanuel E Zervos MD Mario A Camps MD Sarah E Goode RN Alexander S Rosemurgy MD 《Obesity surgery》1997,7(5):414-419
Background: Numerous investigators have attempted to identify prognostic indicators for successful outcome following bariatric
surgery. The purpose of this study was to determine whether degree of obesity affects outcome in super obese [>225% ideal
body weight (IBW)] versus morbidly obese patients (160-225% IBW) undergoing gastric restrictive/bypass procedures. Methods:
Since 1984, 157 patients underwent either gastric bypass or vertical banded gastroplasty. Super obese (78) and morbidly obese
(79) patients were followed prospectively, documenting outcome and complications. Results: Super obese patients reached maximum
weight loss 3 years following bariatric surgery, exhibiting a decrease in body mass index (BMI) from 61 to 39 kg/m2 and an average loss of 42% excess body weight (EBW). Morbidly obese patients had a decrease in BMI from 44 to 31 kg/m2 and carried 39% EBW at 1 year. After their respective nadirs, each group began to regain the lost weight with the super obese
exhibiting a current BMI of 45 kg/m2 (61% EBW) versus 34 kg/m2 (52% EBW) in the morbidly obese at 72 months cumulative follow-up. Currently, loss of 50% or more of EBW occurred in 53%
of super obese patients versus 72% of morbidly obese (P < 0.01). Twenty-six percent of super obese patients returned to within 50% of ideal body weight (IBW) while 71% of morbidly
obese were able to reach this goal (P < 0.01). Co-morbidities and complications related to surgery were similar in each group. Conclusions: Super obese patients
have a greater absolute weight loss after bariatric surgery than do morbidly obese patients. Using commonly utilized measures
of success based on weight, morbidly obese patients tend to have better outcomes following bariatric surgery. 相似文献
65.
目的:观察缺氧及停止缺氧后对大鼠心肌血流量的影响。方法:34只Wistar大鼠,随机分为4组:①平原对照组;②急性缺氧组;③慢性缺氧组;④返回平原组。以放射性生物微球法测定心肌血流量。结果:急性缺氧引起PaO2、心输出量及氧运送量降低,但左、右心室心肌血流量明显增加;慢性缺氧时右心室收缩压、血球压积、血液粘滞性及右心室生理指数明显增加,而心肌血流量接近正常。停止缺氧30d后,上述所有指标均与平原以 相似文献
66.
Kurtis W. Andrews David A. Savitz Irva Hertz-Picciotto 《American journal of industrial medicine》1994,26(1):13-32
Although the adverse effect on pregnancy outcomes at high levels of lead exposure in the workplace has been recognized for years, there is uncertainty regarding the impact of exposure at the lower community exposure levels commonly encountered today. This review summarizes the epidemiologic literature and discusses pertinent methodologic issues and possible sources of interstudy variation. The authors conclude that prenatal lead exposure is unlikely to increase the risk of premature membrane rupture but does appear to increase the risk of preterm delivery. Whether prenatal lead exposure decreases gestational age in terms of infants is unclear. Prenatal lead exposure also appears to be associated with reduced birth weight, but results vary in relation to study design and degree of control for confounding. Adjustment for gestational age, a possible confounder of the birth weight-lead exposure association, did not yield clearer results. 相似文献
67.
MD MPHCecilia Albala MD MScMabel Y ez MPh Mat.Sc.Gabriela Salazar MD MPHFernando Vio 《Nutrition Research》1994,14(12):1797-1809
Body composition measured with isotopic dilution was compared with anthropometric measurements. The study was carried out in 47 subjects from both sexes, 65 to 92 years old. Total body water (TBW), anthropometric measurements, and dynamometry were assessed. TBW was significatively higher in men than women and decreased with age. Dynamometry and fatfree mass were well correlated (r=0.73 in males and r=0.58 in females) and significantly different between sexes. A negative correlation was found for dynamometry with age, being significant for women. Linear regression equations to predict TBW from anthropometric measurements in males and females were obtained: Males: TBW(I)=19.349+0.617 weight(kg) — 0.931 mid-arm circumference(cm)+0.122 dynamometry (kg) Females: TBW(l)=−5.531+0.343 weight(kg)-0.213 triceps skinfold (mm)+ 0.148 dynamometry(kg) + 3.424 wrist diameter (cm). This simple model is proposed for use in epidemiological and field studies where other more sophisticated methods can not be applied. 相似文献
68.
α<Subscript>2β</Subscript> adrenoreceptor 301–303 deletion polymorphism in polycystic ovary syndrome
Alexandros D. Saltamavros George Adonakis Sosanna Kritikou Vasiliki Koika Kleanthis Koufogiannis Kostas Spyropoulos George Kourounis Christodoulos Flordellis Venetsana Kyriazopoulou Neoklis A. Georgopoulos 《Clinical autonomic research》2007,17(2):112-114
α2β adrenoreceptor 301–303 deletion polymorphism does not influence basal metabolic rate, insulin resistance or weight gain in
Greek women with polycystic ovary syndrome. 相似文献
69.
术中输注氨基酸对硬膜外阻滞复合全麻开胸手术患者围术期体温的影响 总被引:2,自引:0,他引:2
目的评价术中输注氨基酸对硬膜外阻滞复合全麻食管癌和贲门癌手术患者围术期深部体温和代谢的影响。方法择期食管癌和贲门癌手术患者21例,ASAⅠ或Ⅱ级,随机分为3组(n =7):从麻醉诱导开始至手术结束,分别静脉输注氨基酸混合液240kJ·h-1(AA组)、等容量乳酸钠林格氏液(LR组)、葡萄糖溶液240kJ·h-1(GLU组)。麻醉诱导前至术后2h每5分钟测定鼓膜温度,于麻醉诱导前即刻、手术开始后1h和术后1h检测指尖血糖,采用4分表法评价术后2h内寒战的发生情况,采用间接测热仪测定术前与术后氧耗。结果与麻醉诱导前即刻比较,术后30min LR组和GLU组氧耗降低,AA组氧耗升高(P<0.01),术后2h LR组、GLU组鼓膜温度降低(P<0.05),AA组差异无统计学意义(P>0.05);与LR组和GLU组比较,AA组术后2h内寒战发生例数减少(P< 0.05),术后30min氧耗增多(P<0.05),LR组与GLU组比较差异无统计学意义(P>0.05)。结论硬膜外阻滞复合全麻开胸手术患者术中静脉输注氨基酸可通过提高基础代谢率,缓解围术期深部体温降低,减少术后寒战发生,而输注葡萄糖不产生此效应。 相似文献
70.
以23例肾功能不全与20例肾功正常患者的唾液尿素氮、钠、钾、舌面pH值和血液的相应生化检查作对照。结果唾液尿素氮、钾与血尿素氮、钾成正相关性。证实了中医“津血同源”“肾为唾”的理论。 相似文献