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41.
Occupational exposure to high concentrations of anesthetic gases (more than 500 ppm of nitrous oxide and more than 15 ppm of halothane and enflurane) can cause neurobehavioral effects in operating room personnel. Factors such as stress and work organization play an additional role in reducing performance capacities. It is still unclear whether these conditions may become the predominant factor in behavioral impairment when exposure to anesthetic gases is reduced; in addition, we wished to ascertain the extent of neurobehavioral and neuroendocrine effects at relatively low levels of exposure to such gases. Therefore the same group of 30 operating room personnel was examined with neurobehavioral tests during gaseous and nongaseous anesthesia. In this way, the neuropsychological performance was examined under the same stress conditions, but with different exposure levels to anesthetic gases. Serum cortisol was measured as an additional biological stress indicator. Prolactin secretion was examined to study possible interference of anesthetic gases with the dopaminergic system. The results were compared with those in a control group of 20 hospital workers from other departments, with similar characteristics in respect of age, sex, and education. During work with gaseous anesthesia, average airborne concentrations (geometric mean) of nitrous oxide were 50.9 ppm (SD 20.8) on the first day of the working week and 54.2 ppm (SD 22.1) on the last day of the working week, whereas average urinary nitrous oxide (geometric mean) were 21.54 g/l on the first day of the working week and 25.67 g/l on the last day of the working week. The operating room workers showed slower reaction times at the end of the week with gaseous anesthesia, compared with workers using nongaseous anesthesia and the control group. At the same time they also showed increased secretion of prolactin, whereas cortisol remained unchanged. Therefore, it can be concluded that lower levels of exposure to anesthetic gases (and not only high exposure levels) cause an impairment of neurobehavioral performance, with the action of stress being less relevant. The mechanism of anesthetics' neurotoxic action seems to be related to interference with the dopaminergic system.  相似文献   
42.
Summary The urinary excretion rate ofD-glucaric acid, an in vivo parameter of the activity of drug metabolizing enzymes, has been determined in patients with chronic renal insufficiency (glomerular filtration rate 4.5–80 ml/min/1.73 m2). The mean value of 22.3 µmoles/d (SD 7.2; n 28) was almost identical to that of healthy controls (22.1 µmoles/d, SD 7.3; n 22). Thus, no inhibitory or enhancing effect of renal insufficiency could be detected. The ability of this parameter to indicate alterations in the activity of hepatic drug metabolism, even in patients with renal insufficiency, was demonstrated by the increased excretion rate of glucaric acid (107 µmoles/d, SD 43.5; n 8; p<0.001) after treatment for 7 days with the enzyme inducer phenobarbital. No significant correlation was found between glucaric acid excretion and sex, age, body weight or body surface in 50 patients. Glucaric acid excretion, therefore, should not be related to the creatinine content of urine samples, since creatinine excretion decreases with severity of renal insufficiency and varies with sex, age, body weight and many other conditions. A single dose of dipyrone (Novalgin®), a further in vivo indicator of drug metabolism, increased glucaric acid excretion on the same day, but no interference was found after a single dose of cortisol.  相似文献   
43.
目的:研究慢性吗啡处理和吗啡戒断对大鼠血清中ACTH及其受体mRNA表达水平的影响。方法:利用放射免疫法测定吗啡依赖及戒断大鼠血清中ACTH及皮质醇的浓度;利用核酸分子杂交技术研究下丘脑糖皮质激素受体(GR)基因表达的改变情况。结果:(1)吗啡依赖组大鼠血清中ACTH及皮质醇的浓度明显低于对照组;戒断d1大鼠血清ACTH浓度仍明显低于对照组(P<0.01),但血清皮质醇的浓度则明显高于对照组(P<0.01);戒断d7大鼠血清ACTH浓度与对照组比较,无显著性差异(P>0.05),而血清皮质醇的浓度仍略高于对照组(P<0.05);(2)吗啡依赖组大鼠下丘脑GR基因表达水平下降(P<0.05),戒断组大鼠GR的基因表达均高于对照组,但无显著性差异(P>0.05)。结论:吗啡类物质的长期使用可以对下丘脑-垂体-肾上腺轴的激素分泌功能及GR的基因表达产生明显的抑制作用。  相似文献   
44.
AIM—To compare the efficacy of hydrocortisone with dopamine for the treatment of hypotensive, very low birthweight (VLBW) infants.METHODS—Forty infants were randomly allocated to receive either hydrocortisone (n=21) or dopamine (n=19).RESULTS—All 19 infants randomised to dopamine responded; 17 of 21 (81%) did so in the hydrocortisone group. Three of the four non-responders in the hydrocortisone group had clinically significant left to right ductal shunting. The incidence of bronchopulmonary dysplasia, retinopathy of prematurity, intraventricular haemorrhage, necrotising enterocolitis, symptomatic patent ductus arteriosus, hyperglycaemia, sepsis (bacterial or fungal) or survival did not differ between groups. The adrenocorticotrophic hormone (ACTH) stimulated plasma cortisol activity, either before or after treatment, did not differ between the two groups of infants. Although a significant difference in efficacy between dopamine and hydrocortisone was not noted (P = 0.108), there were four treatment failures in the hydrocortisone group, compared with none in the dopamine group.CONCLUSION—Both hydrocortisone and dopamine are effective treatments for hypotension in very low birthweight infants.  相似文献   
45.
灵芝孢子粉提取物降血糖作用及机制的实验研究   总被引:5,自引:0,他引:5  
用Stz复制大鼠糖尿病模型观察了灵芝孢子粉乙醇提取物的水溶部分(Glse)的降糖作用及其对胰岛素离体生物活力和内分泌激素Ins、GH、Cor的影响。实验结果表明Glse(相当生药6250mg/kg)对糖尿病大鼠有明显的降低血糖作用,增强耐糖效应,对Stz损伤有一定的对抗作用,促进糖尿病大鼠的Ins分泌,维持GH、Cor的正常水平。含药血清对胰岛素离体生物活力无明显影响  相似文献   
46.
按“虚证辨证参考标准”,筛选出52例典型的阴虚或阳虚患者,另设正常组20例。分别测定3组外周血白细胞、血浆皮质醇及外周血混合白细胞糖皮质激素受体(GR)。结果表明,3组间白细胞、血浆皮质醇差异无显著性(P>0.05),而阴虚、阳虚两组GR值明显低于正常组,差异均有显著性((P<0.01),且阳虚组与阴虚组比较,差异亦有显著性(P<0.05)。提示GR减少可能是典型阴虚阳虚证发展到一定程度的共同病理改变,而GR减少幅度上的差异可能是两者临床表现不一致的病理基础之一。  相似文献   
47.
留针时间对肾阳虚家兔皮质醇及生命质量的影响   总被引:3,自引:0,他引:3  
目的:探索留针时间长短与肾阳虚证的疗效关系。方法:将31只家兔随机分成A.空白对照组;B.模型空白对照组;C.留针时间15min组;D.留针时间30min组;E.留针时间40min组。分组后,除A组外,各组动物于每天上午在腹部皮下注射氢化可的松25mg/kg,连续注射7天。从第11天开始,A、B组只给予正常饲养,C、D、E除给予正常饲养外,按不同的留针时间要求分别给予针刺治疗观察,连续针刺10次。各组家兔分别在造模前(注射氢化可的松前)、造模后(注射氢化可的松后)及治疗10次后3次采血,每次均取清晨空腹血1ml用于检测皮质醇。结果:(1)留针时间15min组皮质醇显著高于留针时间40min组(P<0.05);留针时间15min组与留针时间30min组对比有明显差异(P<0.05);而留针30min组与留针40min组对比无明显差异(P>0.05)。(2)各组家兔生命质量积分比较,空白对照组明显低于模型组与针刺组(15,30及40min)(P<0.05),模型组与针刺组比较,(P<0.05);而留针15min与30min组及40min组间相比无明显差异(P>0.05)。结论:适当地缩短留针时间可以提高针刺治疗肾阳虚证患者的疗效。  相似文献   
48.
目的:探索利用正交试验设计法选择高效液相色谱法(IIPLC)检测尿氢化可的松和可的松水平的最佳试验条件,从而建立检测的方法。方法:对试验中关键因素进行正交试验设计,根据设计方案进行试验,采用液相萃取法提取样品,然后进行HPLC分析。结果:试验次数由原来的243次(3^3+6^3)减少到36次,即可获得满意的试验结果。结论:正交试验设计法对HPLE测定微量物质的备件选择有一定参考和使用价值.  相似文献   
49.
50.
This study investigated the relationships among abuse, nocturnal levels of cortisol and norepinephrine (NE), and coronary heart disease (CHD) risk as measured by the Framingham risk score among women with human immunodeficiency virus (HIV). Participants (n?=?53) from the Chicago Women’s Interagency HIV Study (WIHS), a longitudinal prospective cohort study initiated in 1994, were enrolled in this study during 2012. At WIHS baseline and annual follow-up visits, women were asked about recent experiences of abuse. Summary variables captured the proportion of visits for which women reported recent (past 12 months) physical, sexual, and domestic abuse. Cortisol and NE were assayed in overnight urine samples and adjusted for creatinine levels. Recent abuse was not significantly associated with levels of cortisol, NE, or NE/cortisol ratio. However, higher NE/cortisol ratio was significantly related to higher CHD risk score, higher cortisol was significantly related to lower CHD risk score, and NE was not associated with CHD risk score. In addition, higher proportions of visits with recent sexual abuse, physical abuse, and domestic abuse were significantly related to higher CHD risk score. The association between abuse exposure and CHD risk in the context of HIV infection is likely complex and may involve dysregulation of multiple neurobiological systems. Future research is needed to better understand these relationships and prevention and intervention efforts are needed to address abuse among women with HIV.  相似文献   
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