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191.
壬苯醇醚避孕药膜的临床研究   总被引:3,自引:3,他引:0  
894对健康、已育的育龄夫妇,随机分两组:447对使用壬苯醇醚方型膜,447对使用帽型膜,经两年连续观察。按生命表统计法处理数据。总使用妇女月,方型组9601,帽型组9382,随访率100%。累计停用率、妊娠率和续用率,方型组分别为16.8%、15.3%和83.2%,帽型组为18.4%、15.6%和81.6%,两组无显著差异(p>0.05)。临床和实验室资料表明壬苯醇醚药膜是安全、有效、简便、易于推广的避孕药具之一。  相似文献   
192.
活动性类风湿关节炎患者sICAM-1、sVCAM-1的变化及意义   总被引:2,自引:0,他引:2  
目的 :测定活动性类风湿关节炎 (RA)患者血清中sICAM 1、sVCAM 1水平 ,探讨sICAM 1、sVCAM 1与IL 1、TNF、IFN γ及病情的关系。方法 :用酶联免疫分析法 (ELISA)检测 30例活动性RA患者与 30例健康对照者sICAM 1、sVCAM 1、IL 1、TNF、IFN γ水平。结果 :RA患者血清sICAM 1、sVCAM 1、IL 1、TNF、IFN γ水平明显高于正常对照组 (P<0 0 0 1) ,sICAM 1与IL 1、IFN γ正相关 ,与RF亦呈正相关 ,sVCAM 1与IL 1、TNF、IFN γ正相关 ,与ESR、CRP、Stock指数正相关。结论 :RA患者血清sI CAM 1、sVCAM 1水平显著升高 ,sICAM 1、sVCAM 1可能参与RA发病过程 ,sICAM 1可作为判断病情严重性的指标 ,sVCAM 1可作为观察病情活动性的指标。  相似文献   
193.
将昆明小鼠随机分为低(0.025)、中(0.05)、高(0.1)剂量组及生理盐水对照组,以2号海洛因经腹腔注射染毒,20天后,取睾丸组织制成石蜡切片.HE染色,光镜下观察生精小管上皮细胞的形态变化,并应用图像分析系统对初级精母细胞的形态参数进行了分析;结果表明,(1)光镜观察 对照组及低剂量组小鼠睾丸组织未见明显的变化;中剂量组小鼠睾丸曲细精管上皮有不同程度的组织改变;高剂量组小鼠生精管壁细胞明显地出现上皮层次减少,精子细胞和精子减少,并发现曲细精管内有脱落的生精细胞;(2)形态定量分析显示 低剂量组及中剂量组各形态参数(中剂量组圆形度除外)较对照组无显著差异;高剂量组初级精母细胞核面积、核灰度与对照组相比无显著差异,细胞面积、细胞周长及浆面积较对照组明显增大(P<0.05).而核浆比例、圆形度较对照组有减小(P<0.05).结果提示 海洛因可明显改变小鼠生殖细胞的形态结构.  相似文献   
194.
目的:探讨细胞外基质纤维连接蛋白(FN)、层黏连蛋白(LN)及三维基膜Matrigel胶对平滑肌细胞黏着斑激酶(FAK)表达的影响。方法:免疫荧光组织化学技术对生长在FN、LN和Matrigel胶里的平滑肌细胞FAK的表达进行检测。结果:生长存FN、LN和Matrigel胶里的平滑肌细胞FAK的表达依次为最高、次之和最低,各组之间有统计学意义;平滑肌细胞FAK磷酸化水平和FAK的表达呈正相关,生长在FN上的平滑肌细胞FAK(py397)的表达水平最高,生长在Matrigel胶里的平滑肌表达最低。结论:细胞外基质成分及其构筑对平滑肌细胞FAK的表达具有重要调节作用。  相似文献   
195.
目的:评价双盘封堵器介入治疗继发孔型房间隔缺损(ASD)的临床疗效及安全性。方法:在X线透视和经食道超声心动图(TEE;13岁以下儿童经胸超声心动图,TTE)监视下,采用经皮穿刺放置封堵器方法治疗继发孔型ASD16例,术后立刻、24h、1月、3月进行TEE或TTE和X线胸片检查,以评价其疗效。结果:本组16例封堵器置入均获成功。其中9例术后胸闷症状立即消失,第2天即能下床活动,无特殊不适主诉;另7例症状任2周后逐渐好转。1例术后仍有微量分流,3个月后分流才消失;术后1个月有8例右房及右室内径较术前缩小。14例术后3个月TTE显示ASD无残余分流,封堵器位置良好;另2例失访。结论:经皮封堵治疗继发孔型ASD,是一种有效的介入治疗方法,具有安全、有效、操作简便,成功率高的特点。  相似文献   
196.
The onset response pattern displayed by octopus cells has been attributed to intrinsic membrane properties, low membrane impedance, and/or synaptic inputs. Although the importance of a low membrane impedance generally is acknowledged as an essential component, views differ on the role that ion channels play in producing the onset response. In this study, we use a computer model to investigate the contributions of ion channels to the responses of octopus cells. Simulations using current ramps indicate that, during the "ramp-up" stage, the membrane depolarizes, activating a low-threshold K(+) channel, K(LT), which increases membrane conductance and dynamically increases the current required to evoke an action potential. As a result, the model is sensitive to the rate that membrane potential changes when initiating an action potential. Results obtained when experimentally recorded spike trains of auditory-nerve fibers served as model inputs (simulating acoustic stimulation) demonstrate that a model with K(LT) conductance as the dominant conductance produces realistic onset response patterns. Systematically replacing the K(LT) conductance by a h-type conductance (which corresponds to a hyperpolarization-activated inward rectifier current, I(h)) or by a leakage conductance reduces the model's sensitivity to rate of change in membrane potential, and the model's response to "acoustic stimulation" becomes more chopper-like. Increasing the h-type conductance while maintaining a large K(LT) conductance causes an increase in threshold to both current steps and acoustic stimulation but does not significantly affect the model's sensitivity to rate of change in membrane potential and the onset response pattern under acoustic stimulation. These findings support the idea that K(LT), which is activated during depolarization, is the primary membrane conductance determining the response properties of octopus cells, and its dynamic role cannot be provided by a static membrane conductance. On the other hand, I(h), which is activated during hyperpolarization, does not play a large role in the basic onset response pattern but may regulate response threshold through its contribution to the membrane conductance.  相似文献   
197.
胃癌患者血清CEA、CA19—9及CA72—4联检的临床价值探讨   总被引:2,自引:1,他引:2  
目的:探讨血清CEA、CA19—9及CA72—4联检在胃癌诊断、病情监测及疗效观察中的价值。方法:采用电化学发光技术检测36例正常对照组、42例良性胃病、55例胃癌患者血清CEA、CA19—9、CA72—4的含量,并对胃癌患者进行治疗前后三种肿瘤标志物的含量变化监测随防。结果:胃癌患者血清CEA、CA19—9、CA72—4的阳性率明显高于正常对照组及良性胃病组,差异有显著性(P〈0.01)。胃癌患者治疗后三种肿瘤标志物含量及阳性率较治疗前有明显下降,差异有显著性(P〈0.01)。三者联检的敏感性、准确性均显著提高(P〈0.01)。结论:血清CEA、CA19-9、CA72—4联检有助于提高胃癌诊断的敏感性、同时对疗效观察及术后监测有重要意义。  相似文献   
198.
本研究采用牛房实验小屋,加装不透光百叶窗和透光门廊,从而全面观察药帘对侵入实验小屋蚊虫毒杀情况,包括蚊虫入屋前接触药帘时和屋内蚊虫外逸出屋外后的死亡情况。结果表明,澳氰菊酯、二氯苯醚菊酯毒效强和持效长,浸泡门窗帘后6个月18次试验,对侵入屋内蚊虫毒杀,平均死亡率分别为89.4%和90.6%。两药对入屋内蚊虫的吸血率均没有明显减少,可能与诱饵动物的吸引力有关。二氯苯醚菊酯有明显驱避作用,其减少蚊虫入屋率,按蚊为70.6%,库蚊为75.2%均没有明显减少,阿蚊却没有效应。  相似文献   
199.
The hypothalamus regulates many aspects of energy homeostasis, adjusting both the drive to eat and the expenditure of energy in response to a wide range of nutritional and other signals. It is becoming clear that various neural circuits operate to different degrees and probably serve specific functions under particular conditions of altered feeding behaviour. This review will discuss this functional diversity by illustrating hypothalamic neurones that express neuropeptide Y (NPY), the melanocortin-4 receptor (MC4-R) and the orexins. NPY neurones in the arcuate nucleus (ARC) release NPY, a powerful inducer of feeding and obesity, in the paraventricular nucleus (PVN) and the lateral hypothalamic area (LHA). ARC-NPY neurones are inhibited by leptin and insulin and become overactive when levels of these hormones fall during undernutrition. They may function physiologically to protect against starvation. With disruption of the inhibitory leptin signals due to gene mutations, the NPY neurones are overactive, which contributes to hyperphagia and obesity in the ob/ob and db/db mice and fa/fa Zucker rat. The MC4-R is activated by alpha-melanocyte-stimulating hormone [alpha-MSH; a cleavage product of pro-opiomelanocortin (POMC), which is expressed in the other ARC neurones] and inhibits feeding. This effect is antagonised by agouti gene-related peptide (AGRP), which is coexpressed by the ARC-NPY neurones only. Activation of MC4-R, possibly mediated by blockade of AGRP release, appears to restrain overeating of a palatable diet. This response may be programmed by a transient rise in leptin soon after presentation of palatable food, and rats that fail to do this will overeat and become obese. Orexin-A and -B (corresponding to hypocretins 1 and 2) are expressed in specific LHA neurones. These have extensive reciprocal connections with many areas involved in appetite control, including the nucleus of the solitary tracts (NTS), which relays vagal afferent satiety signals from the viscera. Orexin neurones also have close anatomical connections with LHA glucose-sensitive neurones. Orexin-A induces acute feeding but does not cause obesity. Orexin neurones are stimulated by hypoglycaemia partly via the NTS and inhibited by food ingestion. These neurones may therefore be involved in the severe hyperphagia of hypoglycaemia and short-term control of feeding.  相似文献   
200.
Evaluation of endothelial cell migration with a novel in vitro assay system   总被引:1,自引:0,他引:1  
In this study we introduce a novel in vitro 'oil-drop' assay system for the measurement of endothelial cell (EC) migration, based on the original concept of the Teflon fence assay (Pratt et al., 1984; Am. J. Pathol. 117: 349–354). An aliquot of 15–20,000 human umbilical vein EC (HUVEC) is pipetted through a layer of mineral oil. The cells readily attach, spread and migrate on the surface of a matrix-coated tissue culture dish as a confluent circular monolayer. Migration is measured as the net increase in the total area covered at 24 hours. We have used this system to quantify EC migration on matrices composed of a mixture of type I collagen and either von Willebrand factor (vWF) or fibronectin (FN) in the presence or absence of tumor necrosis factor (TNF). Plating efficiency on both vWF/collagen and FN/collagen, measured by counting cells after attachment and spreading, is about 80%. With this method, migration on vWF/collagen was about 6.4 mm2 and 5.3 mm2 for TNF-treated and untreated HUVEC, respectively. HUVEC migration on FN/collagen was slightly greater – 6.4 mm2 and 6.5 mm2 with and without TNF treatment, respectively. During the 24 hour time period, HUVEC numbers increased 30–40% on vWF/collagen, and 60–80% on FN/collagen, with increased proliferation observed with TNF- treatment. EC proliferation could be completely inhibited by 2 mM hydroxyurea. This assay system has proven useful in our studies to quantify cell migration and proliferation.  相似文献   
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