全文获取类型
收费全文 | 17718篇 |
免费 | 1343篇 |
国内免费 | 723篇 |
专业分类
耳鼻咽喉 | 53篇 |
儿科学 | 59篇 |
妇产科学 | 39篇 |
基础医学 | 1507篇 |
口腔科学 | 330篇 |
临床医学 | 1445篇 |
内科学 | 518篇 |
皮肤病学 | 34篇 |
神经病学 | 2172篇 |
特种医学 | 840篇 |
外国民族医学 | 2篇 |
外科学 | 4080篇 |
综合类 | 2623篇 |
现状与发展 | 1篇 |
预防医学 | 347篇 |
眼科学 | 3196篇 |
药学 | 801篇 |
13篇 | |
中国医学 | 1602篇 |
肿瘤学 | 122篇 |
出版年
2024年 | 67篇 |
2023年 | 298篇 |
2022年 | 512篇 |
2021年 | 670篇 |
2020年 | 661篇 |
2019年 | 454篇 |
2018年 | 524篇 |
2017年 | 567篇 |
2016年 | 634篇 |
2015年 | 609篇 |
2014年 | 1270篇 |
2013年 | 1343篇 |
2012年 | 1107篇 |
2011年 | 1164篇 |
2010年 | 1001篇 |
2009年 | 824篇 |
2008年 | 872篇 |
2007年 | 872篇 |
2006年 | 731篇 |
2005年 | 613篇 |
2004年 | 547篇 |
2003年 | 553篇 |
2002年 | 465篇 |
2001年 | 373篇 |
2000年 | 320篇 |
1999年 | 285篇 |
1998年 | 261篇 |
1997年 | 240篇 |
1996年 | 209篇 |
1995年 | 169篇 |
1994年 | 157篇 |
1993年 | 148篇 |
1992年 | 123篇 |
1991年 | 114篇 |
1990年 | 87篇 |
1989年 | 89篇 |
1988年 | 74篇 |
1987年 | 73篇 |
1986年 | 82篇 |
1985年 | 111篇 |
1984年 | 91篇 |
1983年 | 67篇 |
1982年 | 84篇 |
1981年 | 68篇 |
1980年 | 50篇 |
1979年 | 37篇 |
1978年 | 35篇 |
1977年 | 30篇 |
1976年 | 14篇 |
1975年 | 11篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
Yumiko Motoi Masashi Takanashi Masako Itaya Kazuhiko Ikeda Yoshikuni Mizuno Hideo Mori 《Neuropathology》2004,24(1):60-65
In the present case, a patient in whom limb apraxia and asymmetrical parkinsonism developed suggesting corticobasal degeneration, is reported. Neuropathologic examination revealed numerous tufted astrocytes in the precentral cortex in addition to the characteristic pathologic findings of PSP. Therefore, on the basis of clinicopathologic features, atypical progressive supranuclear palsy was diagnosed. In addition, the brain tissue of the present patient was investigated with an antibody specific for four‐repeat tau (4R‐tau). In the precentral cortex, numerous tau‐positive tufted astrocytes, pretangles, and threads were positive for 4R‐tau. Using a confocal microscopy we demonstrated that tufted astrocytes positive for 4R‐tau were adjacent to astrocytes positive for GFAP. The present findings suggest that accumulation of four‐repeat tau in astrocytes is a degenerative process rather than a reactive process. 相似文献
82.
Transection of an optic nerve (ON) is followed by slow removal of myelin. We studied microglia for the expression of molecules that characterize activated myelin phagocytosing macrophages: MAC-1, FcγII/III receptor (FcR), MAC-2, and F4/80. In-vitro, microglia expressed all molecules and phagocytosed myelin. In-vivo, intact ON displayed high levels of MAC-1, little FcR and F4/80, and no MAC-2. The expression of these molecules was upregulated differentially in in-vivo degenerating ON: MAC-1 uniformly, FcR and F4/80 variably, and MAC-2 sporadically. The distribution of MAC-2 expression correlated best with a pattern of sporadic structural degeneration. Thus in-vivo, ON injury is followed by deficient microglia activation, which we suggest contributes significantly to the slow clearance of myelin. 相似文献
83.
老年黄斑变性的视网膜色素上皮及其视功能的改变 总被引:2,自引:0,他引:2
目的:应用黄斑区密集点矩阵视野并结合眼底荧光血管造影电脑眼底图像分析老年黄斑变性视网膜色素上皮损害与DMMM的视野光敏感度的改变,找出改变的规律有评价其应用价值。方法:用Humphrey-640视野计自行设计DMMM检测AMD干性组51人64只眼湿性且23人27只眼,用Zeiss公司生产的KONTRONELEKTRONIK Inage Analysis Division-计算机图像分析仪总丢失量显 相似文献
84.
Emine Sözeri Dietrich Feist Hans Ruder Karl Schärer 《Pediatric nephrology (Berlin, Germany)》1997,11(3):307-311
Renal lesions have repeatedly been described in Wilson’s disease (WD). We investigated the excretion of total protein, albumin,
low (LMW) and high molecular weight (HMW) proteins, N-acetyl-β-D-glucosaminidase (NAG), and calcium, as well as creatinine clearance, in 24-h urine samples of 41 patients with WD aged 6 – 37
(mean 17) years who had been treated for a period of 0 – 15 (mean 4.5) years with D-penicillamine (900 mg/day). The amount of all protein excreted was significantly increased compared with controls, 39% of
patients presenting with total proteinuria more than two standard deviations from the mean of controls. The changes in protein
excretion depended on the duration of treatment. LMW proteinuria was elevated almost exclusively in the first 2 years after
the start of treatment, indicating early tubular damage. This is supported by an initially high excretion of β2-microglobulin, NAG, and calcium. Increased excretion of HMW proteins, including albumin, persisted over longer periods, which
suggests glomerular injury in some patients, possibly related to the use of D-penicillamine. Creatinine clearance remained roughly within normal limits. We propose that renal function should regularly
be checked in patients with WD.
Received October 26, 1995; received in revised form August 27, 1996; accepted September 20, 1996 相似文献
85.
Summary. A prevalence study of Ureaplasma urealyticum (UU) infection of the male genital tract was carried out in Shanghai between March 1992 and June 1995. Significantly higher frequency of UU infection was found among infertile males (549/1416) as compared to fertile controls (34/375). Examination of 8 specimens each from infertile men and fertile subjects by electron microscopy, immunogold and immunofluorescence techniques, demonstrated adhesion of Ureaplasma urealyticum to the membrane of spermatozoa and exfoliated germ cells. In addition, gold particles on Ureaplasma urealyticum were found to be adhered to the sperm surface in 4 of the 8 samples. Strong specific anti-UU fluorescence was detected in 6 of 8 samples, mainly on the midpieces and post-acrosomal regions of the spermatozoa.
To further study the effects of Ureaplasma urealyticum on fertility, 47 male Sprague-Dawley (SD) rats were infected artificially with Ureaplasma urealyticum serotype 8 (T960). Morphological changes in the seminiferous tubules were observed 3–5 weeks after inoculation in the sacrificed animals. Dramatic impairment of spermatogenesis of both testes was found in 11 rats. Mating experiment confirmed infertility in 12 of 40 rats. Offsprings of the infected rats were significantly smaller than those of controls in terms of prenatal weights and birthweights. 相似文献
To further study the effects of Ureaplasma urealyticum on fertility, 47 male Sprague-Dawley (SD) rats were infected artificially with Ureaplasma urealyticum serotype 8 (T960). Morphological changes in the seminiferous tubules were observed 3–5 weeks after inoculation in the sacrificed animals. Dramatic impairment of spermatogenesis of both testes was found in 11 rats. Mating experiment confirmed infertility in 12 of 40 rats. Offsprings of the infected rats were significantly smaller than those of controls in terms of prenatal weights and birthweights. 相似文献
86.
87.
腰椎间盘突出症患者手术前后血浆内皮素及降钙素基因相关肽的变化 总被引:4,自引:0,他引:4
目的 探讨血浆内皮素 (ET)及降钙素基因相关肽 (CGRP)在腰椎间盘突出症(PLID)患者手术前后的变化及其意义。方法 采用放射免疫法检测 40例正常人及 40例患者手术前后的血浆CGRP及ET值。结果 40例PLID患者术前血浆ET值明显高于正常对照组 ,术后ET值明显低于术前 (P <0 .0 1) ,但患者术后血浆ET值与正常对照组差异无显著性 (P >0 .0 5 )。40例PLID患者术前血浆CGRP值与正常对照组比较差异无显著性 (P >0 .0 5 ) ,40例PLID患者术后疼痛明显改善 ,且其血浆CGRP值明显高于术前及正常对照组 (P <0 .0 1)。正常对照组ET与CGRP无明显相关 ,病组术前ET与CGRP呈正相关 ,而术后两者无明显相关。结论 ET与CGRP共同参与了PLID的发病过程 ,为探讨PLID保守治疗方法提供了依据。 相似文献
88.
A new technique for the treatment of lumbar far lateral disc herniation: technical note and preliminary results 总被引:2,自引:0,他引:2
A newly designed technique for a minimally invasive approach to the laterally herniated disc is presented. Fifteen patients suffering from far lateral disc herniation (extraforaminal) were operated according to this technique. Through a small skin incision (1.5 cm), the paraspinal muscles are spread by dilators, until a working channel of 9 mm inner diameter and 11 mm outer diameter can be placed. The next steps are done through this channel using the surgical microscope. No bone resections are necessary and the facet joints are left untouched. However, partial resection of the intertransverse ligament may be necessary. The mean follow-up period for these 15 patients was 11.5 months, and they were evaluated by using the visual analogue scale (VAS) and the Oswestry Disability Index (ODI). The average surgical time was 43 min. The ODI improved from 30.6 (preoperative) to 14.3 (postoperative). The VAS of leg pain improved from 7 (preoperative) to 3.6 (postoperative), which represented a statistically significant improvement at the significance level of (P<0.01). No intra-operative or early postoperative complications occurred. However, one recurrence did occur, which was treated by the same technique. This technique combines the advantages of three-dimensional visual control (operating microscope) with the minimal surgical trauma of endoscopic techniques, while avoiding some of the shortcomings of both the microsurgical and endoscopic techniques. 相似文献
89.
腰椎间盘术后椎间盘炎的诊治 总被引:1,自引:1,他引:0
目的:探讨腰椎间盘术后椎间盘炎的病因。早期诊断和治疗问题。方法:分析10例术后腰椎间盘炎的临床表现、血象、血流变化、血和病灶细菌培养、腰椎X线平片、CT、MRI所见在发病后的敏感程度,比较3例非手术与7例经前路腹膜后(2例联合后入路)病灶清除,一期椎间植骨融合本治疗的效果。结果:不同程度的发热、痉挛性腰痛、血流增快是本病的特点。MRI、CF、X线片三者的诊断敏感性存在时间差,分别约为发病后1、3、5周。仅2例血和病灶细菌培养均阳性。前路减压植骨融合术减少全身性抗生素和镇痛剂的使用量,明显缩短病程。结论:ESR、MRI对早期确诊、引导手术价值较高。高热、痉挛性腰痛、血沉增快三者具一持续2周得不到控制,可考虑及早手术。手术疗法近期效果更为确切。 相似文献
90.
A prospective and controlled study of training after surgery for lumbar disc herniation (LDH). The objective was to determine
the effect of early neuromuscular customized training after LDH surgery. No consensus exists on the type and timing of physical
rehabilitation after LDH surgery. Patients aged 15–50 years, disc prolapse at L4–L5 or L5–S1. Before surgery, at 6 weeks,
4, and 12 months postoperatively, the following evaluations were performed: low back pain and leg pain estimated on a visual
analog scale, disability according to the Roland–Morris questionnaire (RMQ) and disability rating index (DRI). Clinical examination,
including the SLR test, was performed using a single blind method. Consumption of analgesics was registered. Twenty-five patients
started neuromuscular customized training 2 weeks after surgery (early training group=ETG). Thirty-one patients formed a control
group (CG) and started traditional training after 6 weeks. There was no significant difference in pain and disability between
the two training groups before surgery. Median preoperative leg pain was 63 mm in ETG and 70 mm in the CG. Preoperative median
disability according to RMQ was 14 in the ETG and 14.5 in the CG. Disability according to DRI (33/56 patients) was 5.3 in
the ETG vs. 4.6 in the CG. At 6 weeks, 4 months, and 12 months, pain was significantly reduced in both groups, to the same
extent. Disability scores were lower in the ETG at all follow-ups, and after 12 months, the difference was significant (RMQ
P=.034, DRI P=.015). The results of the present study show early neuromuscular customized training to have a superior effect on disability,
with a significant difference compared to traditional training at a follow-up 12 months after surgery. No adverse effects
of the early training were seen. A prospective, randomized study with a larger patient sample is warranted to ultimately demonstrate
that early training as described is beneficial for patients undergoing LDH surgery. 相似文献