全文获取类型
收费全文 | 51014篇 |
免费 | 4930篇 |
国内免费 | 3535篇 |
专业分类
耳鼻咽喉 | 617篇 |
儿科学 | 497篇 |
妇产科学 | 378篇 |
基础医学 | 5238篇 |
口腔科学 | 777篇 |
临床医学 | 6740篇 |
内科学 | 6563篇 |
皮肤病学 | 745篇 |
神经病学 | 2305篇 |
特种医学 | 1903篇 |
外国民族医学 | 22篇 |
外科学 | 5016篇 |
综合类 | 10283篇 |
现状与发展 | 14篇 |
一般理论 | 2篇 |
预防医学 | 3780篇 |
眼科学 | 1318篇 |
药学 | 5598篇 |
80篇 | |
中国医学 | 3442篇 |
肿瘤学 | 4161篇 |
出版年
2025年 | 17篇 |
2024年 | 838篇 |
2023年 | 1145篇 |
2022年 | 2418篇 |
2021年 | 2851篇 |
2020年 | 2380篇 |
2019年 | 1772篇 |
2018年 | 1842篇 |
2017年 | 1851篇 |
2016年 | 1616篇 |
2015年 | 2540篇 |
2014年 | 3129篇 |
2013年 | 3025篇 |
2012年 | 4161篇 |
2011年 | 4445篇 |
2010年 | 3052篇 |
2009年 | 2468篇 |
2008年 | 2855篇 |
2007年 | 2645篇 |
2006年 | 2517篇 |
2005年 | 2120篇 |
2004年 | 1512篇 |
2003年 | 1431篇 |
2002年 | 1133篇 |
2001年 | 893篇 |
2000年 | 887篇 |
1999年 | 762篇 |
1998年 | 492篇 |
1997年 | 433篇 |
1996年 | 328篇 |
1995年 | 313篇 |
1994年 | 285篇 |
1993年 | 154篇 |
1992年 | 194篇 |
1991年 | 188篇 |
1990年 | 120篇 |
1989年 | 139篇 |
1988年 | 107篇 |
1987年 | 114篇 |
1986年 | 88篇 |
1985年 | 63篇 |
1984年 | 64篇 |
1983年 | 31篇 |
1982年 | 20篇 |
1981年 | 16篇 |
1980年 | 8篇 |
1979年 | 15篇 |
1978年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
用聚合酶链反应技术制备地高辛素标记核酸探针检测国人喉癌人类乳头瘤病毒DNA 总被引:1,自引:0,他引:1
应用聚合酶链反应(PCR)技术制备非放射性探针标记物——地高辛素标记人类乳头瘤病毒(HPV)共有引物探针,对146例喉不同病变的新鲜组织标本(喉癌68例,喉其它病变48例,正常喉组织30例)进行HPV6,11,16,18,31,33,35,42,58共9型HPVSDNAS感染的检测。结果表明,喉癌组HPV感染阳性率45.6%(31/68),喉癌颈转移淋巴结组阳性率21.0%(3/15),喉癌前病变阳性率11.8%(2/17),声带息肉组阳性率6.3%(1/16),15例癌旁及15例癌周正常喉组织均为HPVDNA阴性。文中还对HPV在喉癌中的致病作用及应用PCR技术制备地高李标记HPV共有引物探针的敏感性及特异性进行了讨论。 相似文献
72.
目的:为探讨喉癌颈淋巴结转移的规律,选择手术方法。方法:采用110例临床N0声门上型喉癌的164侧颈廓清术标本淋巴结连续切片方法观察。结果:发现颈淋巴结转移率为35.5%(39/100)。提出临床N0病理转移的特点:1)转移淋巴结大小大多数介于0.5~1.5之间占84.2%。2)转移淋巴结大多数为早期侵入期和生长发展期占86.0%。3)转移淋巴结绝大多数为单发型占74.4%。4)各个T分期均有转移淋巴结。结论:在颈淋巴结处理上,我们支持尽可能同期行选择性颈廓清术的观点 相似文献
73.
目的通过观察血清α-L-岩藻糖昔酶(AFU)活性水平在原发性肝细胞癌(HCC)患者与肝硬化、肝炎及其他恶性肿瘤患者中的变化,评价其在HCC诊断中的价值。方法对44例HCC、18例肝硬化、36例肝炎和30例其他恶性肿瘤患者测定血清AFU活性水平。部分HCC患者曾经接受经导管肝动脉化疗栓塞术(TAE)。结果对照组平均血清AFU活性水平为150.39±35.34nKat/L,HCC组280.11±148.15nKat/L,肝硬化组、肝炎组及其他肿瘤组分别为248.89±68.82、196.67±79.61、168.93±49.89nKat/L。HCC组与对照组及肝炎组、其他肿瘤组之间存在明显差别,但与肝硬化组有部分重叠。结论AFU可作为肿瘤标志物用于诊断HCC与AFP及超声等联合参照应用。 相似文献
74.
脑震荡患者在恢复期或伤后3个月内,头部仍有胀痛,搏动性疼痛,或有紧缩感,脑力劳动后多加重,常伴有头昏、脑晕、耳鸣、记忆力减退、失眠及植物神经功能紊乱等症状,为脑震荡后遗症。祖国医学认为,头为清阳之会,五脏精华之血、六腑清阳之气均上注于头。若头部受外伤则阻滞气血之运行,脑失其养或清阳遏阻则可出现上述症状。笔者近两年来用王不留行籽耳穴贴压治疗脑震荡后遗症20例,疗效满意,现报告如下。 相似文献
75.
Adjuvant monoarthritis was induced by the injection of 50μl Complete Freund‘s Adjuvant(CFA) into ankle joint of adult SD rats. Electroacupuncture (EA)was performed on Huantiao (GB30)and Yanglingquan (GB 34) (0.5-1.5 v, 4-16 Hz, 30 min) after the injection. 相似文献
76.
Zinc-positive neurons and terminals, known to be associated with the glutamatergic projections in the brain, can be demonstrated by the histochemical Timm method and later modifications thereof. The adult rat neocortex contain a uniform lamination of zinc-positive cells with specific projections to, e.g., the striatum. We have previously reported that fetal neocortical grafts implanted in the adult rat neocortex combined with rearing in an enriched environment can improve behavioral functions and reduce the secondary atrophy of thalamus after cortex infarction in adult rats. In order to examine whether the expression of zinc positivity is ontogenetically inherent to neocortical neurons we grafted fetal neocortical tissue to aspiration or ischemic lesions of the frontoparietal neocortex of adult rats, followed by histochemical visualization of the vesicular zinc pool by selenite or sulfide. One further aim of the study was to elucidate to what extent the distribution of zinc-containing neurons and terminals in the grafts depended on rearing under different environmental conditions. The foremost finding of the present study was that the overall density of zinc-containing terminals in fetal cortical transplants placed in brain infarcts of adult spontaneously hypertensive rats is higher when the rats are reared in an enriched environment. Moreover, the presence and expression of zinc-positive neurons and terminals do not seem to be ontogenetically inherent to the cortical neurons as the fetal neocortical grafts placed in aspiration lesions contained no zinc-selenide-positive neurons and few or no zinc-selenide-positive terminals. The presence or expression of zinc-positive cells may thus be induced by ingrowth of fibers and terminals from the host brain as transplants placed in the ischemic lesions expressed both zinc-positive neurons and terminals. 相似文献
77.
OBJECTIVE: To examine the expression of apoptosis-related genes c-IAP2 and caspase-4 in sinonasal squamous carcinoma. To investigate the role and mechanism of the two apoptosis-related genes in nasal cavity and sinus squamons carcinoma. METHODS: Forty-one pathologically confirmed specimens of nasal cavity and sinus squamons carcinoma were subjected for immunohistochemical staining to analyze the expression of c-IAP2 and caspase-4, in addition 10 normal nasal mucosa were used as control. RESULTS: The positive rate of c-IAP2 in sinonasal squamons carcinoma was 87.8%, among which 14 cases were strongly stained(+ + +), 15 cases were stained(+ +), 7 cases were stained (+), only 5 cases were negative. In 10 normal control tissues, no case was stained(+ + +), 2 cases were stained (+ +), 3 cases were stained(+), the other 5 cases were negative. Higher level expression of c-IAP2 protein was detected more often in squamons carcinoma specimens than that in normal nasal mucosa. There was statistically significant difference between the two groups for the staining(P < 0.05). The expression of c-IAP2 was not correlated with clinical staging (P > 0.05), but there were positive correlation with clinical prognosis (P < 0.01) and pathological classification (P < 0.01); The positive rate of caspase-4 in nasal cavity and sinus squamons carcinoma was 58.5%, among which 4 cases were strongly stained (+ + +), 7 cases were stained (+ +), 13 case was stained(+), 17 cases were negative. The expression of caspase-4 protein was more deletion in squamons carcinoma specimens than that in control group, there was statistically significant difference between the two groups for the staining (P < 0.05). The expression of caspase-4 protein was negatively correlated with clinical prognosis (P < 0.01) and pathological classification ( P < 0.01), not correlated with clinical staging(P > 0.05). The expression of c-IAP2 was negativelly correlated with the experssion of caspase-4. CONCLUSIONS: The results indicates that in sinonasal squamous carcinoma, c-IAP2 is activated, while caspase-4 is restrained, the signal transduction pathway of apoptosis is arrested, leading to surviving of tumor cells, this maybe directly associated with the development of sinonasal squamons carcinoma, and with the failure of tumor trentment. 相似文献
78.
79.
Autoradiographic localization of tachykinin and calcitonin gene-related peptide receptors in adult urinary bladder 总被引:1,自引:0,他引:1
PURPOSE: In bladder, sensory afferent nerve fibers contain the "sensory neuropeptides" substance P (SP), neurokinin A (NKA) and calcitonin gene-related peptide (CGRP), which interact with tachykinin NK-1 and NK-2 receptors and CGRP receptors, respectively. The purpose of this study was to examine the autoradiographic distribution of these three receptor types in the human bladder, to determine whether the anatomic location of the receptors was consistent with their known functional roles. MATERIALS AND METHODS: Specimens of urinary bladder from 9 patients (58-74 years) were obtained at cystectomy. Frozen sections of dome were labeled with [125I]-Bolton-Hunter [Sar9,Met(O2)11]-SP (NK-1 receptors), [125I]-[Lys5,Tyr(I2)7,MeLeu9,Nle10]-NKA(4-10) (NK-2 receptors) and [125I]-rat CGRP-I. Binding sites were visualized using emulsion autoradiography. RESULTS: NK-1 receptors were found over the endothelium of arterial blood vessels within the detrusor muscle and lamina propria, and over small vessels in the subepithelium. NK-2 receptors were seen over the detrusor muscle and very sparsely over blood vessels, whereas CGRP receptors were expressed densely over the smooth muscle layer of arteries and arterioles, and weakly over collecting venules. NK-1 and CGRP receptors were not observed over the detrusor muscle. CONCLUSIONS: Although the afferent nerves contain all three peptides, not all cell types express receptors for each peptide. The general distribution of receptors is in good agreement with the location of nerves, and with the known actions of SP and CGRP as vasodilator agents, and of NKA (but not SP or CGRP) in contracting the detrusor muscle. 相似文献
80.
儿童塑型性支气管炎的诊断与治疗 总被引:21,自引:0,他引:21
目的 报告 5例儿童塑型性支气管炎病例 ,并复习相关文献 ,总结诊断及治疗方法。方法 2 0 0 1年5月至 2 0 0 3年 10月 ,对 5例年龄 9个月至 10岁 ,主诉为反复咳嗽、气促并出现急性呼吸窘迫的塑型性支气管炎患儿 ,给予支气管镜检及气道内异物取出术 ,配以反复纤维支气管气道内冲洗、呼吸机机械通气、胸部物理治疗、强化护理及吸痰等综合治疗。结果 5例中 ,4例支气管镜检取出异物 ,1例为吸痰时吸出支气管状条形异物 ,经病理检查确诊。双侧支气管病变 1例 ,左侧支气管病变 2例 ,右侧支气管病变 1例 ,另 1例吸痰时可吸出。死亡 2例 ,其余 3例均痊愈出院。病理组织学分型按Seear方法 :Ⅰ型 3例 ,Ⅱ型 2例。结论 塑型性支气管炎是一种高危性疾病 ,确诊需依靠支气管镜检查和病理组织学检查。支气管镜异物取出术是唯一有效的治疗方法。气道护理和胸部物理治疗是重要的辅助治疗手段。 相似文献