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31.
The isolation and analysis of nucleated fetal cells (NFCs) from maternal blood may represent a new approach to noninvasive prenatal diagnosis. Although promising, these techniques require highly accurate separation of NFCs from nucleated cells of maternal origin; the two major problems limiting these techniques are the relative rarity of fetal cells in maternal blood and the need to establish their fetal origin. We now report a novel procedure that has allowed accurate separation of NFCs from maternal cells. The technique reported involves direct micromanipulator isolation of histochemically identified hemoglobin F‐positive nucleated cells to obtain fetal nucleated red blood cells (FNRBCs) of high yield and purity. Using this technique, followed by cell‐by‐cell multicolor fluorescence in situ hybridization (FISH) analysis of purified FNRBCs, we were able to detect some of the most common human aneuploidies (including Down syndrome, Klinefelter syndrome, and trisomy 13) in 33 pregnant women referred for amniocentesis. The procedure used, which can be completed in <72 hrs, produced complete concordance with the results of amniocentesis. We also confirm findings of prior studies suggesting that the number of FNRBCs in maternal circulation is remarkably higher in abnormal pregnancies than in normal pregnancies, especially in women carrying a fetus with trisomy 21. © 2001 Wiley‐Liss, Inc.  相似文献   
32.
应用扫描电镜观察了22例糖尿病人4400个红细胞形态的异常百分比,并测定红细胞的渗透脆性。结果表明随着糖尿病病程延长、糖化血红蛋白升高,口形、嵴形红细胞的百分比明显升高(2.64±1.27比4.29±1.03,P<0.001),细胞渗透脆性明显上升(0.17±0.04比0.33±0.17,P<0.05)。提示,糖尿病人异常形态红细胞的出现不仅与红细胞的能量代谢障碍外,还可能与红细胞所处的高血糖、高血脂、高血液粘度的环境有关。而影响红细胞的渗透脆性的因素较为复杂,红细胞的圆形隆起在降低其渗透脆性方面起了重要作用。  相似文献   
33.
目的 分析胎龄<34周早产儿不同断脐方式下血红蛋白、胆红素及相关并发症差异,为早产分娩行挤压脐带断脐法(UCM)提供临床依据。方法 回顾性分析115例经阴道分娩的胎龄<34周的早产儿,根据断脐方式分为UCM组(n=59)和立即断脐(ICC)组(n=56),比较两组早产儿娩出后血红蛋白变化趋势和输血量、住院期间经皮胆红素值及光疗时间以及颅内出血、早产儿视网膜病变、支气管肺发育不良和坏死性小肠结肠炎的发生率。结果 UCM组出生后1 h内、出生后1周左右和出院前血红蛋白显著高于ICC组(t=2.246、2.123、1.886,P<0.05),住院期间ICC组早产儿输血次数及每人次输血量显著多于UCM组(χ2=2.145,t=2.160,P<0.05)。两组经皮胆红素达峰时间均为3~6 d,UCM组经皮胆红素值显著高于ICC组(t=2.231、2.654、2.686、2.038,P<0.05),两组光疗时长差异无统计学意义(P>0.05)。早产儿住院期间发生颅内出血、视网膜病变、支气管肺发育不良及坏死性小肠结肠炎等并发症两组间差异无统计学意义(P>0.05)。结论 与正常断脐相比,挤压脐带可增加胎龄<34周早产儿的血容量和血红蛋白量,减少住院期间输血次数及输血量,且不增加患儿病理性黄疸和并发症的风险,可作为胎龄<34周早产儿首选的断脐方法。  相似文献   
34.
摘 要:目的:了解上海市高桥社区外来务工子弟小学学生血红蛋白值的变化特征,为制定预防贫血的策略提供参考依 据。方法:以2019学年上海市高桥社区外来务工子弟小学1~4年级所有在校学生为研究对象,分别于2019年6月和2020年 6月对其进行血红蛋白值检测。结果:共检测学生730人,其中男生417人 (57.12%)、女生313人 (42.88%)。男生两次血红 蛋白均值分别为 (128.95±13.72) g/L和 (133.07±13.32) g/L,女生分别为 (126.25±12.33) g/L和 (128.87±12.84) g/L,男生 两次血红蛋白均值均高于女生,差异有统计学意义 (t值分别为8.19和4.33,P值均<0.05)。7岁组、8岁组、9岁组和10岁 组学生第二次血红蛋白均值均高于第一次,差异均有统计学意义 (t值分别为5.82、3.34、5.53和3.11,P值均<0.05)。肥胖 组、超重组、正常组、轻度消瘦组、中重度消瘦组学生血红蛋白均值第二次均高于第一次,差异均有统计学意义 (t值分别 为 3.50 、2.94 、7.08 、2.26 和 2.20,P值均<0.05)。研究对象贫血发病率、恢复率和人群持续率分别为 13.32%、61.48%和 6.44%。女生贫血发病率和人群持续率均高于男生,差异均有统计学意义 (χ2值分别为4.45,4.35,P值均<0.05);各年龄组 贫血发病率、恢复率和人群持续率比较,差异均有统计学意义 (χ2值分别为19.91、7.62和12.78,P值均<0.05);不同营养 状况学生贫血发病率、恢复率和人群持续率比较,差异均有统计学意义 (χ2值分别为 16.65、5.11和 37.26,P 值均<0.05)。 结论:应加强对外来务工子弟小学学生的贫血检测工作,干预措施重点实施对象为女生、低年级、消瘦和持续贫血的学生。  相似文献   
35.
Background: Diet has been associated with poor glycemic control in diabetes. Few studies have examined this association in people with type 1 diabetes (T1D), who are at a higher risk for cardiovascular disease than people without diabetes. Methods: We report data from cross-sectional and longitudinal analyses from a coronary artery calcification in type 1 diabetes (CACTI) study (n = 1257; T1D: n = 568; non-diabetic controls: n = 689) collected between the years 2000 and 2002. Participants completed a validated food frequency questionnaire, a physical examination, and biochemical analyses. Dietary patterns based on variations in food group intake were created with principal components analysis. Linear regression was used to examine the associations of dietary patterns, macronutrients, and food groups with HbA1c in a model adjusted for relevant covariates and stratified by diabetes status. Results: Three dietary patterns were identified: “fruits, veggies, meats, cereal”, “baked desserts” and “convenience foods and alcohol” patterns. At baseline, a higher intake of the “baked dessert” pattern was significantly associated with higher HbA1c in T1D at baseline as well at year 6 of the study when adjusted for age, sex, BMI, total calories, and diabetes duration. No such associations were observed in the case of non-diabetic controls. Dietary saturated fats and animal fats were also positively associated with HbA1c in adults with T1D at baseline and/or at year 6. Conclusions: The habitual intake of a dietary pattern that is characterized by an increased intake of added sugar and saturated fats, such as in baked desserts, may increase risks of poor glycemic control in T1D.  相似文献   
36.
目的研究丁酸盐对血红蛋白合成的诱导作用和不同给药方式对丁酸盐诱导的K562细胞向红系分化的影响。方法以K562细胞为体外模型,采用联苯胺染色定性技术检测细胞内血红蛋白,比较丁酸盐不同浓度、不同给药方式诱导K562细胞前后的阳性细胞率;测量波长为414nm的D(λ)值和醋酸纤维膜电泳检测药物诱导的血红蛋白含量的变化。结果不同浓度的丁酸盐诱导后联苯胺染色阳性细胞率(BZ%)增加4~6倍,细胞平均血红蛋白较用药前增加9~14倍;丁酸盐选择性地刺激HbF合成;单次脉冲式给药BZ%在72 h达高峰,峰值在19%~28%之间,之后迅速下降,约在7~9d接近用药前水平,孵育时间的长短与BZ%上升以及上升后持续时间的长短无关;丁酸盐持续诱导的BZ%变化与一次脉冲式用药总体趋势相似;间断脉冲式用药BZ%在72 h达到峰值后持续保持在20%~30%之间的水平,直至3个周期的用药结束。结论丁酸盐可诱导珠蛋白基因表达,促进血红蛋白的合成,尤其能够选择性地刺激胎儿血红蛋白的合成增加;间断脉冲式用药能够持续诱导K562细胞向红系分化,可作为丁酸盐治疗β-珠蛋白基因缺陷疾病的理想给药方式。  相似文献   
37.
The efficacy of spirulina platensis (S. platensis) as an add-on therapy to metformin and its effect on atherogenic keys in patients with uncontrolled Type 2 Diabetes Mellitus (T2DM) was evaluated. Sixty patients were randomly assigned to S. platensis (2 g/day) or placebo group for three months while continuing metformin as their usual treatment. The efficacy of S. platensis was determined using the pre- and post-intervention HbA1c levels (primary outcome) as well as tracking FBS and lipid profiles levels (TC, LDL-C, TG, and HDL-C) as secondary outcomes at the different treatment time points (0,30,60,90 days). During the three–month intervention period, supplementation with S. platensis resulted in a significant lowering of HbA1c (↓1.43, p < 0.001) and FBS (↓ 24.94 mg/dL, p < 001) levels. Mean TG in the intervention group was found to be significantly lower in the intervention group than in controls (p < 0.001). Total cholesterol (TC) and its fraction, LDL-C, exhibited a fall (↓41.36 mg/dL and ↓38.4 mg/dL, respectively; p < 0.001) coupled with a marginal increase in the level of HDL-C (↑3 mg/dL; p < 0.001). Add-on therapy with S. platensis was superior to metformin regarding long-term glucose regulation and controlling blood glucose levels of subjects with T2DM. Also, as a functional supplement, S. platensis has a beneficial effect on atherogenic keys (TG and HDL-C) with no adverse events.  相似文献   
38.
39.
Maternal diabetes is known to be related to an increase in birth weight of the offspring. However, the mechanism of the association is not entirely clear. In addition, the contribution of the demographic, obstetric and metabolic factors to birth weight in diabetic mothers is not well defined. All the diabetic women (68 requiring insulin-treatment and 403 on diet alone) and a random sample of 1 in 12 of all non-diabetic women (893 women) who delivered in one regional hospital between March 1987 and June 1988 inclusive, were included in the study. Tests for gestational diabetes are routinely performed in our pregnant women population, thus, the study is a population based one. The mean birth weight of infants of diabetic mothers adjusted for gestational age was higher than in those of non-diabetic mothers. However, no relationship was found between maternal glycosylated hemoglobin measured at delivery and the infants birth weight. Furthermore, at each week of gestation, infants born to diabetic mothers were heavier than the infants of non-diabetic mothers (for weeks 37 to 40, p < 0.05), while no differences were found in glycosylated hemoglobin levels between the two groups at any time. In a multivariate model we showed that after controlling for gestational age, the only factors which independently and significantly affected birth weight in our population were diabetes, ethnic origin, and the parity of the mother. Our findings support the possibility that substances which induce hyperinsulinemia, other than glucose, may be related to the higher birth weight of infants of diabetic mothers.  相似文献   
40.
卒中应激性高血糖与糖尿病并发卒中的鉴别诊断研究   总被引:7,自引:0,他引:7  
目的 :探讨糖化血红蛋白和糖化血清蛋白在卒中应激性高血糖与糖尿病并发卒中的鉴别诊断中的作用。方法 :通过测定卒中伴高血糖患者血液中的糖化血红蛋白和糖化血清蛋白水平 ,判断这种血糖升高的原因是应激性高血糖还是糖尿病并发卒中。结果 :2 4例脑出血伴高血糖的患者中 ,应激性高血糖 11例 ,糖尿病并发卒中 13例 ;38例脑梗死伴高血糖的患者中 ,应激性高血糖 8例 ,糖尿病伴发卒中 30例。结论 :糖化血红蛋白和糖化血清蛋白鉴别应激性高血糖与糖尿病并发卒中方法可靠 ,值得推广。  相似文献   
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