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21.
自乳化释药系统的体外评价   总被引:7,自引:0,他引:7  
目的 探讨自乳化释药系统的体外评价方法。方法 通过测定自乳化时间、乳化后乳剂粒径的大小及模型药物的体外溶出行为对自乳化释药系统进行体外评价。结果 优选出的自乳化处方10min内已基本乳化完全,乳化后乳剂粒子大小大多数在3μm左右,以吲哚美辛和尼莫地平为模型药物制备出自乳化释药系统,体外溶出结果表明:与混悬液相比,两种药物的体外溶出显提高。结论 自乳化释药系统能够提高难溶性药物的体外溶出。  相似文献   
22.
An important operational aspect of Syringe Exchange Programmes (SEPs) is the venue of service delivery. This report describes the programmatic features of the Sacramento Area Needle Exchange (SANE), an illegal SEP operating in California, USA. SANE utilises “satellite exchangers” to distribute the bulk of its syringes and HIV risk reduction supplies. Advantages of relying primarily on Designated Exchangers (DE) for delivery of SEP services are that it: (1) allows for coverage of a large geographical area; (2) keeps operational cost low; (3) provides syringes to clients who may not want to or cannot use fixed site programmes; (4) limits the possibility of detection of programme personnel and clients by law enforcement. Limitations are that: (1) it is not as conducive as fixed sites to providing a wide range of ancillary services; (2) it may not be optimal for drug users who do not want to be reliant on other people for access to syringes; (3) those who receive services from a satellite exchanger may not derive as much counselling and referral services as direct exchangers. The lack of legal status, political support and adequate funding threatens the programme’s existence.  相似文献   
23.
Intravenously injected polystyrene microspheres with functional amino groups (AP-MSs, 0.2,1.0, and 4.0 urn in diameter) were cleared from the blood very rapidly. The calculated half-lives for 0.2-, 1.0-, and 4.0-μm AP-MSs were about 55,60, and 50s; no significant differences were found with 106,107, and 108 microspheres/rat. Loading experiments showed that the liver, spleen, lung, kidney, and heart had a very high capacity to take up AP-MSs. The AP-MSs were distributed mainly to the liver, lung, and spleen, whereas other organs contained less than 1 % of injected AP-MSs. In terms of numbers of AP-MSs per gram of tissue, the highest contents were found in spleen, liver, and lung for 0.2-, 1.0-, and 4.0-um AP-MSs, respectively. There was indication of redistribution of particles from one organ to another during the first 6 h after injection. Chondroitin sulfate A (Chon) and hyaluronic acid (Hya) adsorbed or covalently linked to AP-MSs increased uptake in the liver, with Chon AP-MSs (adsorbed or linked) showing the best effect: about 25% increase compared with unadsorbed 1-μm AP-MSs. Experiments with separated cells in vitro demonstrated that 1 um AP-MSs, intravenously injected, associated only with Kupffer cells. When the microspheres were adsorbed with Chon, there was also association with liver endothelial cells. This finding indicates that conjugation of microspheres with ligands for endothelial receptors may be a useful method for directing microspheres to specific organs, even if the receptors are not by themselves phagocytic  相似文献   
24.
25.
心脏机械瓣膜置换术后分娩的临床研究   总被引:5,自引:0,他引:5  
王以新  苏醒  李斌  刘陶 《北京医学》2003,25(4):243-244
目的 探讨心脏机械瓣膜置换术后分娩的临床处理措施。方法 对19例心脏机械瓣膜置换手术后妊娠及分娩的资料进行回顾性分忻。结果 19例心脏机械瓣膜置换术后产妇均安全度过孕产期。分娩前后心功能Ⅰ~Ⅲ级,分娩时出血200~260m1,胎儿体重2950--3146g。无母婴死亡者,无胎儿出血以及畸形者。结论 心脏机械瓣膜置换术后心功能Ⅰ~Ⅲ级可安全度过孕产期。分娩采用剖宫产术为宜。妊娠期间口服抗凝剂(华法林)不增加分娩时母婴出血和新生儿畸形。  相似文献   
26.
不同分娩方式妇女放置三种IUD的术时评价   总被引:2,自引:1,他引:1  
目的:研究不同分娩方式妇女放置三种新型含铜宫内节育器(CulUD)的术时评价。方法:将观察对象按经阴道和经剖宫产的不同分娩方式分为两组,每组均随机放置CyneFix IN IUD、MCu功能性IUD和TCu380A IUD,记录两组放置不同种IUD的扩宫情况、置器疼痛反应和置器时间。结果:放置GyneFix IN IUD和TCu380A IUD在不同分娩方式组中扩宫率、痛觉评分、置器时间无显著差异(P>0.05)。放置MCu功能性IUD在剖宫产分娩组扩宫率为92.5%,显著高于阴道分娩组的33.3%(P<0.05);痛觉评分为8.62±0.82分,显著高于阴道分娩组(P<0.01);置器时间为(9.62±3.15)min,较另两种IUD置器时间显著延长(P<0.05)。结论:GyneFix IN IUD和TCu380A IUD置器术时扩宫率低、费时少,疼痛反应轻,不受分娩方式影响。  相似文献   
27.
《野叟曝言》的“文格”与夏敬渠的创作人格有一致性,但存在明显的、不可忽视的矛盾,这种矛盾对《野叟曝言》的文本价值产生了极复杂的影响。导致夏敬渠“人格”与《野叟曝言》“文格”矛盾的原因是多方面的,研究视角不能简单化、绝对化。  相似文献   
28.
Two hundred and seventy healthy university students were surveyed in December 1995 using Bond's Defense Style Questionnaire (DSQ) to measure the subjects' defense mechanisms. At the same time, a survey using Byrne's R-S Scale (Repression–Sensitization Scale) of the MMPI (Minnesota multiphasic personality inventory) and five psychiatric symptom indexes (anxiety, sense of inadequacy, sensitivity, depression and impulsive anger) selected from the CMI (Cornell Medical Index-Health Questionnaire) was conducted. Three factors were extracted from the DSQ through factor analysis: immature defenses, neurotic defenses, and mature defenses. The results of analysis of variance revealed the following: (i) for anxiety and anxiety related symptoms, both immature defenses and neurotic defenses indicated principal effect; (ii) for impulsive anger and depression, immature defenses presented principal effect; and (iii) for sensitivity and impulsive anger, interaction between a mature defense style and neurotic defense style was noted. The relationship between defense styles and psychiatric symptoms in healthy people is studied in this paper.  相似文献   
29.
Summary The effects of opioids on the permeability of the blood-brain barrier (BBB) were examined in mice with sodium fluorescein as an indicator of the permeability. The brain was perfused with saline 30 min after injection of sodium fluorescein (40 mg/kg, i. v.) and examined by fluorometry. Morphine hydrochloride (0.3–10 mg/kg, s. c.) markedly increased the brain level of sodium fluorescein dose-dependently without influencing the plasma level, when administered 20 min before sodium fluorescein injection. Intracerebroventricularly (i. c. v.) injected morphine hydrochloride (0.5 and 1.0 Erg) increased the brain sodium fluorescein level. Buprenorphine (0.1 and 0.5 mg/kg, s. c.) was also effective. However, pentazocine, ethylketazocine, U-50488H and SKF-10047 had no significant influence. The i.c.v. administration of [D-Ala2, McPhe4, Gly(ol)5]enkephalin (0.1 g) and [D-Ala2, D-Leu5]enkephalin (0.5 g) but not of [D-Thr2, Leu5]enkephalin-Thr increased the brain level of sodium fluorescein significantly. A small dose of naloxone (i. p.) significantly inhibited the effects of morphine, buprenorphine, [D-Ala2, McPhe4, Gly(ol)5]enkephalin and [D-Ala3, D-Leu5]enkephalin. ICI-174864 co-administered i. c. v. with [D-Ala2, D-Leu5]enkephalin was ineffective in antagonizing the effect of the latter. These findings suggest that the stimulation of µ opioid receptors results in an increase in BBB permeability to sodium fluorescein. Send offprint requests to K. Saeki  相似文献   
30.
Using a reverberatory epilepiform discharge of hippocampal-parahippocampal circuits termed maximal dentate activation, this study investigated whether the local release of nitric oxide within these circuits functions as an antiepileptic agent. Two nitric oxide synthase inhibitors (l-nitro-arginine methyl ester and 7-nitro-indazole) and a guanylate cyclase inhibitor (methylene blue) were tested, and none had a significant effect on the time to onset or duration of maximal dentate activation. A membrane-permeable analogue of cyclic guanosine monophosphate (cGMP), 8-bromo-cGMP, caused an increase in the time to onset and a decrease in the duration of maximal dentate activation. The number of neurons expressing NADPH diaphorase activity (a marker for nitric oxide synthase) was also examined after repeated elicitation of maximal dentate activation. After 18 seizures there was a significant, but transient, decrease in the number of hilar/subgranular neurons that were NADPH diaphorase-positive. The decrease was only seen at 1 h after the last seizure. There was no induction of NADPH diaphorase activity. These results are not consistent with the hypothesis that, in hippocampal-parahippocampal circuits in vivo, nitric oxide is released in response to neuronal activity and then acts to terminate the neuronal activity.  相似文献   
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