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31.
32.
肢端黏液样炎性纤维母细胞肉瘤2例及文献复习 总被引:1,自引:2,他引:1
目的探讨肢端黏液样炎性纤维母细胞肉瘤的临床病理学特征及鉴别诊断。方法对2例发生在下肢末端的黏液样炎性纤维母细胞肉瘤进行光镜观察和免疫组化标记,并复习文献。结果2例发生在下肢末端的病程较长的渐进性肿块,术后局部复发。镜检:病变呈多结节状,边界不清;黏液样基质中见数量不等的各类炎细胞浸润,散在或灶性分布梭形、奇异形和多空泡状脂肪母细胞样3种形态的瘤细胞。免疫表型:肿瘤细胞Vim弥漫阳性,CD68和CD34灶性阳性,CK、SMA、HHF-35、S-100蛋白、CD45、CD45R0、CD15、CD30均阴性。结论此病病程较长,术后易局部复发,是一种低度恶性的肿瘤。鉴于病变黏液样基质及各类炎细胞浸润的背景较为突出,而特征性的瘤细胞稀疏,应注意与炎症性病变或具有相似组织形态的良性或恶性肿瘤鉴别。 相似文献
33.
Yang YZ Tian JM Tian JT Chen ZQ Deng XJ Zhang DH 《Journal of biomedical materials research》2000,52(2):333-337
Graded porous titanium coatings have been deposited on titanium substrates for dental implants by plasma spraying in an argon atmosphere. X-ray diffraction (XRD), scanning electron microscopy (SEM), surface roughness measurement, and tensile strength tests were performed on graded porous coatings. The results showed that Ti(3)O(5) was formed in the outermost surface of the porous coatings due to oxidation. The graded porous coatings consisted of three layers. The outer layer was full of macropores with a surface roughness of approximately 100 microm. The diameter of many macropores reached and even surpassed 150 microm, which could be beneficial for tissue to grow into the coating. The middle layer consisted of a mixture of micropores and macropores. The inner layer was a very dense and tight interface layer that included mechanical, physical, and metallurgical bonding. In tensile strength tests, testing bars peeled off the coatings, because the adhesive agent fractured, but the coatings remained intact. 相似文献
34.
The intent of the present study was to use chemical or electrical stimulation of cerebellar afferents to determine how different stimulation paradigms affect the pattern of activation of different populations of neurons in the cerebellar cortex. Specifically, we analyzed immediate changes in neuronal activity, identified neurons affected by different stimulation paradigms, and determined the time course over which neuronal activity is altered. In the present study, we used either systemic (harmaline) or electrical stimulation of the inferior cerebellar peduncle (10 and 40 Hz) to alter the firing rate of climbing and mossy fiber afferents to the rat cerebellum and an antibody made against the proto-oncogene, c-fos, as a marker to identify activated neurons and glia. In control animals, only a few scattered granule cells express nuclear Fos-like immunoreactivity. Although no other cells show Fos-like immunoreactivity in their nuclei, Purkinje cells express Fos-like immunoreactivity within their somatic and dendritic cytoplasm in control animals. Within 15 min of chemical or electrical stimulation, numerous granule and glial cells express Fos-like immunoreactivity in their nuclei. Cells in the molecular layer express Fos-like immunoreactivity following harmaline stimulation in a time and lobule specific manner; they do not appear to be activated in the electrical stimulation paradigm. Following harmaline injections, there is an initial loss of Fos-like immunoreactivity in the cytoplasm of Purkinje cells; 90 min later, nuclear staining is observed in a few scattered Purkinje cells. Following electrical stimulation, the cytoplasmic staining in Purkinje cells is enhanced; it is never present in the nucleus. Data derived from this study reveal cell-specific temporal and spatial patterns of c-Fos activation that is unique to each paradigm. Further, it reveals the presence of an activity dependent protein in the cytoplasm of Purkinje cell somata and dendrites. 相似文献
35.
36.
P D Wilson L Geng X Li C R Burrow 《Laboratory investigation; a journal of technical methods and pathology》1999,79(10):1311-1323
Mutations in the PKD1 gene are responsible for autosomal dominant polycystic kidney disease (ADPKD). Although PKD1 has been cloned and shown to be expressed at high levels in the fetal ureteric bud and ADPKD cystic epithelia in the human kidney, the function of its encoded protein, "polycystin-1" is unknown. In this study we used primary and immortalized human renal epithelial cell lines derived from normal fetal, adult, and ADPKD kidneys, that endogenously express PKD1, to study the biologic function of the polycystin-1 protein. ADPKD renal epithelial cells expressed high levels of polycystin-1 protein and showed increased adhesion to type I collagen by comparison with normal adult human renal epithelia that expressed little polycystin. Adherent ADPKD cells also expressed high levels of alpha2beta1-integrin and their attachment was inhibited by a functional monoclonal antibody to alpha2-integrin. Double labeling and confocal microscopy as well as coimmunoprecipitation analysis showed overlapping colocalization of polycystin-1 with alpha2beta1-integrin as well as with the focal adhesion proteins vinculin and paxillin in multiprotein clusters localized to focal areas of cell membrane contact with type I collagen matrix after short periods of attachment. Immunoprecipitation and Western immunoblot studies also showed that polycystin-1 was posttranslationally modified by tyrosine phosphorylation. These studies suggest that the PKD1-encoded protein is part of a large multiprotein complex in epithelial cells that functions in the regulation of extracellular matrix interactions with the plasma membrane and cell cytoskeleton. 相似文献
37.
VALUE AND LIMITATIONS OF SINUS NODE FUNCTION TE.ST
BY ATRIAL PACING IN SICK SINUS SYNDROME DIAGNOSIS
Sun Rui-long孙瑞龙 Chen Xin陈新 Wang Fang-zhengHu Sheng-jun胡绳俊 Tian Rui-guo田瑞国and Qi Lian-xiaClinical Electrophysiology Laborato''ry Institute of Cardiovascular Diseases Chinese Academy of Medical Sciences Beijing 《中华医学杂志(英文版)》1984,97(2):142-146
In order to evaluate the significance of the
sinus node function test by transvenous atrial
pacing in the diagno,sis of sick sinus syndrome
(SSS), sinus node recovery time (SRT), co]rrected
sinus node recovery time (CSRT) and total atrio-
sinus and sino-atrial conduction time (SACT)
are observed in 69 patients including non-SSS
group 39 cases and SSS group 30 cases.
According to our data, we suggest criteria
for sinus node dysfunction as follows. SRT>1,400
ms and/or A-V junctional esca.pe before sinus
recovery and;or secondary pause, CSRT>560 ms.
total SACT>300 ms. With l item abnormal, the
false positive rat.e in the non-SSS group is 7.7c7。
and the false negative rate in the S.SS group 3.30i"
with 2 items abnormal, the false positive rate in
the non-SSS group Oi and the false negative
rate in the SSS grOiup 6.7'70.
Atropine test results are compared with that
of atrial pacing, 95.8To and 84.2% are compatible
with each other in these 2 groups. In order to
cut the use of invasive technic to the minimum,
we propose performing the atropine test first.
Only in those with unexplainable test results
should the trial pacing test. be resorted to.. 相似文献
38.
皮下通道型胆囊肝胆管成形术治疗肝胆管结石 和胆管狭窄的临床研究 总被引:2,自引:1,他引:1
目的:总结皮下通道型胆囊肝胆管成形术的临床效果。方法:统计了1994年以来我院76例行STHG手术患者的适应症、临床效果及术后早期并发症。并选择同期实施的125 列行传统胆肠吻合(CJ)的患者进行对照。结果:STHG的手术适应症与传统胆肠吻合基本相同;STHG组患者的手术时间、住院时间、术中出血量明显少于CJ组,术后恢复良好,仅2例次并发症。结论;该术式既保存了胆囊及Oddi括约肌功能,又保证了胆汁的生理流向;防止了肠液的反,所以避免了消化功能紊乱,防止了反 流性胆管炎,对患者的影响小,是一种较为理想的治疗肝胆管结石和肝门胆管狭窄的术式。 相似文献
39.
大鼠去势后胸腺变化的组织学及超微结构的观察 总被引:2,自引:0,他引:2
目的:探讨去势对大鼠胸腺淋巴细胞超微结构与细胞功能的影响。方法:分别于去势大鼠术后2周、4周、6周、8周后,取胸腺组织进行HE染色和透射电镜观察。结果:实验表明去势导致胸腺淋巴细胞结构坏死,或者细胞器严重受损。结论:去势后胸腺淋巴细胞形态和功能均受到损害。 相似文献
40.
鸡贫血病毒VP 3基因的克隆及其体外凋亡诱导效应的研究 总被引:1,自引:0,他引:1
用PCR方法扩增了鸡贫血病毒标准株的vp3基因,并将其克隆于真核表达载体pcDNA3上,构建了重组体pcDNA-vp3.经酶切鉴定及测序分析表明,该片段和预期相符.在体外利用LipofectAMINETM介导的基因转染,将pc-DNA-vp3、pcDNA3分别转入肝癌细胞系HepG2和二倍体肝细胞系L-02中,转染后的RT-PCR结果证实vp3基因在细胞中得到了表达.同时利用筛选稳定表达细胞株的技术和原位细胞凋亡检测法,证明了鸡贫血病毒是以凋亡的方式诱导细胞死亡,并且只诱导癌细胞的凋亡,而不诱导正常或二倍体细胞死亡.表明鸡贫血病毒vp3基因很可能成为一种极具潜力的抗肿瘤生物制剂. 相似文献