首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   167篇
  免费   6篇
  国内免费   1篇
儿科学   16篇
妇产科学   26篇
基础医学   23篇
临床医学   1篇
内科学   9篇
神经病学   14篇
特种医学   3篇
外科学   7篇
综合类   9篇
预防医学   59篇
药学   2篇
肿瘤学   5篇
  2023年   1篇
  2022年   1篇
  2021年   1篇
  2020年   5篇
  2019年   7篇
  2018年   10篇
  2017年   6篇
  2016年   12篇
  2015年   1篇
  2014年   9篇
  2013年   16篇
  2012年   10篇
  2011年   18篇
  2010年   10篇
  2009年   7篇
  2008年   9篇
  2007年   10篇
  2006年   6篇
  2005年   3篇
  2004年   1篇
  2003年   5篇
  2002年   3篇
  2001年   3篇
  1999年   3篇
  1998年   1篇
  1997年   1篇
  1996年   1篇
  1995年   4篇
  1994年   1篇
  1991年   3篇
  1988年   2篇
  1987年   1篇
  1985年   2篇
  1984年   1篇
排序方式: 共有174条查询结果,搜索用时 78 毫秒
151.

Objective

To investigate the influence of age at menarche (AM) and age at natural menopause (ANM) on glycemic control in patients with type 2 diabetes mellitus (T2DM).

Methods

A cross-sectional study was undertaken in Jiangsu, China. Logistic regression was used to evaluate the association between AM/ANM and glycemic control.

Results

1195 (14.3%) premenopausal and 7149 (85.7%) postmenopausal women were included in this study. With the increase of AM per 1?year, patients had a low risk of uncontrolled FPG (≥7?mmol/L) and uncontrolled HbA1c (≥7%), as well as poor glycemic control (FPG ≥7?mmol/L and HbA1c ≥7%) after adjusting for age and BMI (model I, P?<?0.05) with odds ratio (OR) 0.965, 0.978 and 0.962 respectively. Whereas after adjusting for age, BMI, education, duration of diabetes, smoking, drinking and antidiabetic treatment (model II) as well as further plus diabetic familial history and physical activity (model III), the association between AM and glycemic control was not significant (P?>?0.05). Compared with premenopausal women, postmenopausal women had a low risk of uncontrolled FPG and uncontrolled HbA1c after adjusting for confounders in model II (P?<?0.05). Furthermore, both patients with early ANM (<45?years) and late ANM (>55?years) had a high risk of uncontrolled HbA1c as well as poor glycemic control even adjusted for full confounders in model III (P?<?0.05 for all).

Conclusion

Early AM, early and late ANM were significantly associated with worse glycemic control. Ascertaining the AM and ANM in women with T2DM may help to identify the risk predisposed to worse glycemic control.  相似文献   
152.
女性不同初潮年龄的手腕骨发育特征   总被引:2,自引:0,他引:2  
对早潮(11岁前)、晚潮(15~16岁)和普通(12.5~13.5岁)月经初潮3组女性进行手腕骨发育状况的对比观察。结果表明,各组间初潮时间年龄均差别很大,而组间的初期平均骨龄却非常接近(早期组与晚期组平均时间年龄值差值4.71岁,平均骨龄差值仅0.32岁)。164名女生初潮时间年龄的变异范围是初潮骨龄变异范围的2倍。各组间Ⅱ掌骨皮质厚度均值存在明显差异,但消除了骨干粗细影响因素后,求得的骨皮质指数间均值差别很小,表明女孩初潮时骨骼矿化水平比较接近。  相似文献   
153.

Objective

To estimate the mean age at menarche and its association with nutritional status in Brazilian adolescents.

Methods

The study sample included female adolescents aged 12–17 who participated in a multicenter, school-based, country-wide, cross-sectional study entitled The Study of Cardiovascular Risk in Adolescents (Estudo de Riscos Cardiovasculares em Adolescentes [ERICA]). Mean and median ages at menarche in Brazil were estimated. The association of age at menarche with sociodemographic data and nutritional status were described as means and their respective 95% confidence intervals. Survival analysis was used to assess the age at menarche according to nutritional status categories and the log-rank test was used to compare the medians. Bivariate and multivariate analyses were performed using Cox regression to verify the association between menarche and other variables.

Results

A total of 73,624 students were evaluated, comprising 40,803 girls, of whom 37,390 reported menarche at a mean age of 11.71 years and a median of 12.41 years. Median age at menarche was lower in overweight and obese girls (p < 0.001). The multivariate analysis showed that excess weight (HR = 1.28; 95% CI 1.21–1.36; p < 0.001) and studying in a private school (HR = 1.06; 95% CI 1.02–1.10; p = 0.003) were associated with menarche.

Conclusions

This is a pioneering study in Brazil with national and regional representativeness to estimate the mean and the median age of occurrence of menarche. Adolescents with excess weight had an earlier menarche than their peers, even after adjustment for confounding factors.  相似文献   
154.
目的 调查上海市浦东新区妇女的自然绝经年龄、行经年限,观察初潮年龄与生育次数对自然绝经年龄和行经年限的影响.方法 2007年1月至2008年7月,以参加上海市浦东新区宫颈癌筛查的、年龄≥56岁的15 083例自然绝经妇女为研究对象,采用一对一的问卷方式,调查妇女的初潮年龄、生育次数、自然绝经年龄、行径年限等情况.将研究对象按年龄分为56~60、61~65、66~70和>70岁4个组.采用方差分析方法,比较各年龄组绝经年龄和行经年限的差异;采用多因素回归方法分析年龄组别、初潮年龄、生育次数与绝经年龄和行经年限的关系.结果 (1)自然绝经年龄:最小为29岁,最大为61岁,平均为(50.6±3.7)岁.56~60、61~65、66~70和>70岁4个年龄组的平均绝经年龄分别为(50.9±3.4)、(50.7±3.7)、(50.0±4.1)、(49.6±4.0)岁,随着年龄组的年轻化,平均绝经年龄呈逐渐增加趋势,最小年龄组与最大年龄组比较,平均绝经年龄相差1.36岁.(2)行经年限:最长为48年,最短为12年,平均(34.3±4.1)年.56~60、61~65、66~70和>70岁组的平均行经年限分别为(34.6±3.8)、(34.3±4.1)、(33.9±4.6)、(33.2±4.5)年;随着年龄组的年轻化,平均行经年限呈逐渐延长趋势,最大年龄组与最小年龄组比较,相差1.41年.(3)初潮年龄对绝经年龄和行经年限的影响:相关分析显示,初潮年龄与绝经年龄无明显相关性(r=0.02),初潮年龄与行经年限呈负相关(r=-0.43).(4)生育次数对绝经年龄和行经年限的影响:生育1~2次妇女的绝经年龄明显高于生育0次和≥3次的妇女,差异有统计学意义(P<0.05);但生育1次与2次的妇女及生育0次与≥3次的妇女绝经年龄比较,差异均无统计学意义(P>0.05).生育1次的妇女行经年限明显长于生育1次以上的妇女,生育2次的妇女行经年限明显长于生育0次和≥3次的妇女,差异也有统计学意义(P<0.05);生育0次与≥3次者行经年限比较,差异无统计学意义(P>0.05).(5)行经年限的多因素回归分析:初潮年龄与行经年限呈明显的负相关(r=-0.97,P<0.001);不同年龄组别的行经年限相关分析显示,61~65、66~70和>70岁组与56~60岁组比较,差异均有统计学意义(r=-0.18,P=0.020、r=-0.78,P<0.001和r=-1.23,P<0.001);生育1~2次者的行经年限明显长于生育0次和≥3次者.(6)绝经年龄的多因素回归分析:初潮年龄与绝经年龄无相关性(r=0.02);但不同年龄组别的绝经年龄的多因素分析显示,61-65、66~70和>70岁组妇女的绝经年龄与56~60岁组比较,差异也有统计学意义(r=-0.18,P=0.020、r=-0.78,P<0.001、r=-1.23,P<0.001).生育1~2次的妇女绝经年龄明显高于生育0次和≥3次者,但生育1次与2次,0次与≥3次者间比较,差异均无统计学意义.结论 (1)上海市浦东新区妇女的绝经年龄逐渐增加,行经年限呈延长趋势;(2)初潮年龄和生育次数是影响绝经年龄和行经年限的重要因素;(3)随着初潮年龄的年轻化,行经年限逐渐延长;(4)生育1~2次能明显推迟绝经年龄并且延长行经年限,而多次生育(≥3次)对绝经年龄和行经年限均无明显影响.  相似文献   
155.
The aim of this study was to evaluate variations in the size and body proportions of elite female gymnasts associated with individual differences in maturity status. The subjects were 150 gymnasts, 14.0–17.9 years of age, who had participated in the 24th World Championship in Artistic Gymnastics, Rotterdam. Height, body mass, sitting height and biacromial and bicristal breadths were measured. Leg length was estimated as the height minus sitting height, and the ratio of sitting height to height was calculated. Information on menarcheal status was obtained by means of a questionnaire, and hand-wrist radiographs were taken to assess skeletal maturity status. For the purpose of data analysis the gymnasts were divided into three maturity groups within each single-year chronological age (CA) group from 14 to 17 years: pre-menarcheal (n=65); post-menarcheal but not skeletally mature (SA<16.0 years, n=37); post-menarcheal, skeletally mature (n=48). Differences among the groups were tested with analysis of variance and post hoc Tukey tests. The results showed that pre-menarcheal gymnasts are smaller in all dimensions compared to post-menarcheal gymnasts in all age groups but that the significance of differences varies. Post-menarcheal, skeletally mature gymnasts are heavier than pre-menarcheal gymnasts, but weight does not differ between gymnasts in the two post-menarcheal groups (with one exception, 16 years). Post-menarcheal, skeletally mature gymnasts have proportionally shorter legs than gymnasts in the other two maturity categories. Elite gymnasts of contrasting maturity status show similar trends in body size and proportions similar to those of non-athlete adolescent girls of contrasting maturity status. The results highlight the need to consider maturity-associated variation in the body dimensions of gymnasts before attributing their characteristics to the demands of regular training.  相似文献   
156.
广东省中小学生月经初潮与首次遗精年龄现状及趋势分析   总被引:4,自引:0,他引:4  
目的分析广东省学生月经初潮和首次遗精年龄现状及近10年变化趋势。方法利用2005、2000和1995年广东省学生体质健康调查研究数据,采用概率单位回归法计算月经初潮平均年龄(MMA)和首次遗精平均年龄(FSMA)。结果2005年城乡女生MMA分别为12.51、13.26岁,城市比农村提前约0.75岁;城乡男生FSMA分别为14.23、14.79岁,城市比农村提前约0.56岁;城市女生在身高、体重突增后约1年月经来潮,农村女生在身高、体重突增后约3年月经来潮;城市男生在身高突增后约1年、体重突增后约2年出现遗精,农村男生在身高突增后约1年、体重突增后的同一年出现遗精;2005年城乡女生MMA分别比1995年推后0.27岁和0.47岁,城乡男生FSMA均比1995年推后0.63岁。结论广东省学生月经初潮和首次遗精年龄城市早于农村;近10年城乡学生月经初潮和首次遗精的年龄推后,尤以城市女生明显,是性发育年龄提前的长期趋势已经停止的有力证据。  相似文献   
157.
目的探讨性成熟较早的女孩手腕骨骨龄、重点标志及骨皮质发育特点,为临床医学、预防医学相关实践和基础理论研究提供科学依据。方法在青春期发育调查基础上,选择11岁前发生月经初潮的62名女生,拍照手腕骨X线片,判定骨龄,并观察重点骨发育标志,测量第Ⅱ掌骨骨皮质厚度。结果被检女生的月经初潮年龄均值为10.6岁,平均骨龄达13.3岁,其中52人(83.9%)初潮骨龄处于13.0~14.0岁之间。该群体的初潮平均骨龄比她们的初潮平均时间年龄大2.7岁。本组女生月经初潮时59人拇指内侧种籽骨已萌出,但有3例尚未见该籽骨。被检对象的第Ⅱ掌骨皮质厚度已达到该地区12.3岁发育水平。结论采用平均骨龄预测女孩月经初潮,无论对普通女孩,还是对性成熟较早者,均有实际意义。  相似文献   
158.
中国青春期女生月经初潮较早与身体素质的关系   总被引:1,自引:0,他引:1  
目的 分析中国青春期女生月经初潮较早与身体素质的相关关系.方法 资料均来自2010年全国学生体质与健康调查数据,采用概率单位回归法计算月经初潮年龄的第10百分位数(P10)概率界值,将界值以前已来月经者定义为月经初潮较早(9.0~11.6岁),共筛选出初潮较早女生1072名,按城乡、年龄(精确到0.1岁),以1∶1频数匹配未来初潮女生,共1072名,并选取其50 m跑、立定跳远、50 m×8往返跑(7~12岁)、仰卧起坐4项身体素质指标.按年龄、城乡分层采用单水平t检验分析初潮较早组与未来潮组女生各项身体素质指标的差异;构建多水平单因变量和多因变量模型分析月经初潮较早与各项身体素质指标的关系.结果 共纳入2144名学生,城市11.0 ~11.6岁组初潮较早女生的50 m跑时间、立定跳远距离、仰卧起坐个数分别为(9.78±0.85)s、(153.81±18.59) cm、(27.79±10.25)个,未来潮学生分别为(10.01 ±0.90)s、(149.71±18.72)cm、(26.28±10.11)个,差异均有统计学意义(t值分别为4.02、3.43、2.31,P值均<0.01);农村11.0~11.6岁组初潮较早女生50 m×8往返跑时间、仰卧起坐个数分别为(120.92±13.06)s、(24.96±8.97)个,未来潮女生分别为(120.92±13.06)s、(22.96±9.83)个,差异均有统计学意义(t值分别为3.89、2.77,P值均<0.01),10.0 ~10.9岁初潮较早、未来潮女生50 m×8往返跑时间分别为(128.52±15.74)s、(123.89±13.50)s,差异有统计学意义(t=2.14,P<0.05).多水平分析结果显示,月经初潮较早女生50 m跑时间、立定跳远距离、仰卧起坐个数分别比未来潮女生高0.12s、3.14 cm、1.11个(Waldx2值分别为4.00、6.22、4.07,P值均<0.05),而50 m×8往返跑时间比未来潮学生低1.95 s(Waldx2=3.96,P<0.05).结论 中国青春期女生月经初潮较早可能与身体速度素质、爆发力素质、肌力素质增加及耐力素质下降有关.  相似文献   
159.
目的 探讨中国青春期女生月经初潮较早与身体形态发育的关系.方法 资料均来自2010年全国学生体质与健康调查数据,采用概率单位回归法计算月经初潮年龄的第10百分位数(P10)概率界值,将界值以前已来月经者定义为月经初潮较早(9.0~11.6岁),共筛选出初潮较早女生1072名,按城乡、年龄(精确到0.1岁)1∶2频数匹配未来潮女生2144名,并选取其身高、体重、坐高、胸围、BMI和身高坐高指数进行分析.采用t检验、wilcoxon秩和检验分析9.0~11.6岁各组中月经初潮较组与未来潮女生各项指标的差异,采用x2检验分析超重、肥胖率的差异;采用多水平模型分析月经初潮较早与各项形态指标及超重肥胖的关系.结果 纳入1072名月经初潮较早者以及2144名未来潮者.初潮较早组女生身高、坐高、胸围、体重和BMI分别为(151.42±7.46) cm、(80.86±4.21)cm、(73.88 ±7.72)cm、(44.32±9.35)kg和(19.18 ±3.03) kg/m2,未来潮组分别为(144.86±7.55)cm、(76.96±4.05)cm、(67.25±6.94) cm、(36.07 ±7.88)kg和(16.64±2.48) kg/m2,差异均有统计学意义(Z值分别为-22.20、-23.69、-24.38、-23.12、-20.17、-6.33,P值均<0.01);多水平分析结果显示,9.0~11.6岁组月经初潮较早与各项身体形态发育指标均具有相关性(P值均<0.05),初潮较早组女生与未来潮组比较,身高、坐高、胸围、体重和BMI分别高5.28 cm、3.37 cm、5.53 cm、6.37 kg、1.79 kg/m2;分年龄段分析,发现初潮较早组与未来潮组之间身高、坐高和体重的差异随年龄增加呈抛物线型变化趋势,胸围呈“U”形变化;9.0~10.8、10.9~11.0、11.1 ~11.2岁组初潮较早女生出现超重肥胖的风险分别是未来潮组的2.98倍(95% CI:1.92 ~4.63)、6.76倍(95% CI:2.79 ~16.39)、2.99倍(95%CI:1.40~6.40).结论 中国青春期女生月经初潮较早与身高、坐高、体重和胸围等生长发育指标有关,且与超重肥胖密切相关.  相似文献   
160.
The timing of puberty is complex, possibly involving many genetic factors that may interact with environmental influences. Familial resemblance for age at menarche was studied in a sample of 4,995 female twins, 1,296 sisters, 2,946 mothers and 635 female spouses of male twins. They had indicated their age at menarche as part of a larger longitudinal survey. We assessed assortative mating for age at menarche, gene–environment interaction effects and estimated the heritability of individual differences in pubertal timing. There was significant evidence of gene–environment interaction, accounting for 1.5% of the variance. There was no indication of consistent mate assortment on age at menarche. Individual differences in age at menarche are highly heritable, with additive genetic factors explaining at least 70% of the true variation. An additional 1.5% of the variation can be explained by a genotype–environment interaction effect where environmental factors are more important in individuals genetically predisposed for late menarche. Edited by Stacey Cherny  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号