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991.
S Yao  K Ying  Z Li  L Shen 《中国医疗器械杂志》1999,23(4):207-9, 238
A spot weld & heating treatment tri-uses device based on modern mechanical-electric technique, was developed for dental spot weld, stainless steel orthodontic wire heating-reversion and Ni-Ti orthodontic wire heating-overload metamorphism. The device will be very helpful instrument in orthodontic clinic. The paper not only described the operating methods of the device, but also discussed the Performance-improved principles of stainless steel orthodontic wire and the principles of heating overload metamorphism of Ni-Ti orthodontic wire.  相似文献   
992.
993.
Hongshan  Chen  Chenjin  Jin 《眼科学报》1999,15(1):61-64
Purpose: To investigate the compliance of the patients with ocular fundus diseases with recommendation for follow-up examination after laser treatment, and the underlying reasons for non-compliance.Methods: 53 patients with ocular fundus disease were asked to fill in a questionnaire which includes the socio-demographic characteristics, fear of the fundus disease, conception of the laser treatment and the motivation for staying healthy. Variables were compared for the compliers group and the non-compliers group by chi-square test. Result; Of the 53 subjects, 35 were classified as non-compliers and 18 were classified as compliers. There was no statistically significant difference between the two groups on all selected socio-demographic factors, conception of the laser treatment and the motivation for staying healthy. Significant difference was found between the two groups on two of those items concerning the fear of the diseases (P<0. 05). About half of the participants showed the lack of knowledge about  相似文献   
994.
目的观察和研究敏感期内、末不同时限单眼斜视(monocularstrabismus,MS)和单眼剥夺(monoculardeprivation,MD)幼猫视皮质、外侧膝状体的脑源性神经营养因子(brainderivedneurotrophicfactor,BDNF)的可塑性变化。从形态学、分子神经生物学角度探讨不同时限MS和MD幼猫视  相似文献   
995.
人眼晶体悬韧带的张力测定   总被引:1,自引:0,他引:1  
目的:进行人眼晶体悬韧带部位及其张力的测定。 方法:对26只离体尸眼进行测定。悬韧带的最大张力规定为:在其放松及最大伸张情况下,从睫状突到嵌入晶体前囊膜内的悬韧带的距离的差值。  结果:悬韧带在拉断之前平均能被拉长4.48±1.78mm,年轻组为5.33±1.19mm,老年组为2.17±0.70mm。无韧带区老年组为6.98±0.70mm,年轻组为7.66±0.42mm,平均为7.48±0.58mm。结论:悬韧带具有一定的张力,随着年龄的增长,悬韧带有向囊膜中心生长的趋势,无韧带区随年龄的增加而减小,悬韧带的张力随年龄的增加而减少。  相似文献   
996.
患儿男,10个月。因双眼凝视2天于1998年3月29日来我院就诊。追问病史,患儿自2个半月前开始服用浓鱼肝油滴剂,每日3次,每次维生素A3.5万IU,服用2个月后,患儿逐渐出现食纳减退、精神萎靡、烦躁、易激惹、口唇皲裂、前囟隆起等症状。既往体健,无感染及高热惊厥史。体检:体温37.6℃,发育正常,营养中等。精神差,表情淡漠,头发稀少,口唇皲裂、结痂,前囟隆起,心肺腹正常,神经系统正常。眼部检查:双眼向内凝视,视乳头边缘模糊。B超、CT提示脑积水,颅内压增高。诊断:维生素A慢性中毒。立即停用维生素…  相似文献   
997.
分离性垂直偏斜(简称DVD)亦称上隐斜。该病病因不清,治疗方法亦各不相同,临床较多采用上直肌减弱术。下斜肌止端转位术是KratZ1989年报道的一种新的DVD矫正术。近三年我们采用上直肌后徙术及下斜肌止端转位术治疗DVD,取得较好疗效。现报告如下,l临床资料11对象本组16例,年龄7一月岁,男6例,女10例,合并内斜9例,合并外斜5例,Helveston综合征2例。患者术前均行视力、屈光状态、眼位、注视性质、眼底、三棱镜及同视机检查。1.2手术设计及效果DVD手术定量主要根据第一眼位用交替遮盖试验测量最大斜视程度来决定,一般在Drp影…  相似文献   
998.
1. 12,14-dichlorodehydroabietic acid (12,14-Cl2DHA) reduced GABA-stimulated uptake of 36Cl- into mouse brain synaptoneurosomes suggesting inhibition of mammalian GABA(A) receptor function. 2. 12,14-Cl2DHA did not affect the binding of [3H]-muscimol to brain membranes but displaced specifically bound [3H]-EBOB. The inhibitory effect on [3H]-EBOB binding was not reversible. 12,14-Cl2DHA reduced the availability of [3H]-EBOB binding sites (Bmax) without changing the KD of the radioligand for remaining sites. 12,14-Cl2DHA did not affect the rate of association of [3H]-EBOB with its chloride channel receptor, but increased the initial rate of [3H]-EBOB dissociation. 3. 12,14-Cl2DHA enhanced the incidence of EPSCs when rapidly applied to cultured rat cortical neurones. Longer exposures produced block of IPSCs with marked increases in the frequency of EPSCs and min EPSCs. 12,14-Cl2DHA also irreversibly suppressed chloride currents evoked by pulses of exogenous GABA in these cells. 4. Ultimately, 12,14-Cl2DHA inhibited all synaptic traffic and action currents in current clamped cells indicating that, in contrast to picrotoxinin (which causes paroxysmal bursting), it is not fully selective for the GABA(A) receptor-chloride channel complex. 5. The depolarizing block seen with 12,14-Cl2DHA in amphotericin-perforated preparations implicates loss of Ca2+ buffering in the polarity change and this may account for inhibition of spontaneous action potentials. 6. Our investigation demonstrates that 12,14-Cl2DHA blocks GABA-dependent chloride entry in mammalian brain and operates as a non-competitive insurmountable GABA(A) antagonist. The mechanism likely involves either irreversible binding of 12,14-Cl2DHA to the trioxabicyclooctane recognition site or a site that is allosterically coupled to it. We cannot exclude, however, the possibility that 12,14-Cl2DHA causes localized proteolysis or more extensive conformational change within a critical subunit of the chloride channel.  相似文献   
999.
The biology of fracture healing: optimising outcome   总被引:3,自引:0,他引:3  
Optimising the results of fracture treatment requires a holistic view of both patients and treatment. The nature of the patient determines the priority targets for outcome, which differ widely between the elderly and the young, and between the victims of high and low energy trauma. The efficacy of treatment depends on the overall process of care and rehabilitation as well as the strategy adopted to achieve bone healing. The rational basis for fracture treatment is the interaction between three elements: (i) the cell biology of bone regeneration; (ii) the revascularisation of devitalized bone and soft tissue adjacent to the fracture; and (iii) the mechanical environment of the fracture. The development of systems for early fracture stabilisation has been an advance. However, narrow thinking centred only on the restoration of mechanical integrity leads to poor strategy--the aim is to optimise the environment for bone healing. Future advances may come from the adjuvant use of molecular stimuli to bone regeneration.  相似文献   
1000.
Brief ischaemia or heat stress protects the myocardium against ischaemia-reperfusion injury. Heat stimulus evokes release of sensory nerve transmitters, including calcitonin gene-related peptide (CGRP). Since CGRP has been shown to play an important role in the mediation of ischaemic preconditioning, the present study examined whether early or delayed preconditioning induced by retrograde hyperthermic perfusion in vitro or by whole-body hyperthemia in vivo also involves endogenous CGRP. Isolated rat hearts were perfused in the Langendorff mode and subjected to 30 min global ischaemia and 30 min reperfusion. Heart rate, coronary flow, left ventricular pressure and its first derivatives (±dp/dt) were recorded and the CGRP-like immunoreactivity (CGRP-LI) content and the release of creatine kinase (CK) during reperfusion were measured. Retrograde hyperthermic perfusion (42 °C) for 5 min improved the recovery of cardiac function, decreased the release of CK and elevated the content of CGRP-LI in the coronary effluent. CGRP8–37 (10–7 mol/l), a selective CGRP receptor antagonist, abolished the cardioprotection by heat stress. Pretreatment with capsaicin (50 mg/kg s.c.), which specifically depletes sensory nerve transmitter content, abolished both the cardioprotection and the increased release of CGRP-LI. Whole-body hyperthermia (42 °C for 15 min) caused an increase in the plasma concentration of CGRP-LI. Early or delayed protection was shown in the hearts obtained from the animals subjected to whole-body hyperthermia 10 min or 48 h before the experiments. The early or delayed protection by heat stress was also abolished by pretreatment with capsaicin. The present study suggests that, in the rat, the early and delayed cardioprotection induced by heat stress involves endogenous CGRP. Received: 31 December 1998 / Accepted: 6 April 1999  相似文献   
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