全文获取类型
收费全文 | 65291篇 |
免费 | 7386篇 |
国内免费 | 1236篇 |
专业分类
耳鼻咽喉 | 266篇 |
儿科学 | 2033篇 |
妇产科学 | 1475篇 |
基础医学 | 4658篇 |
口腔科学 | 1823篇 |
临床医学 | 7474篇 |
内科学 | 12835篇 |
皮肤病学 | 632篇 |
神经病学 | 4845篇 |
特种医学 | 2345篇 |
外国民族医学 | 2篇 |
外科学 | 6502篇 |
综合类 | 5765篇 |
现状与发展 | 10篇 |
一般理论 | 11篇 |
预防医学 | 11486篇 |
眼科学 | 903篇 |
药学 | 5048篇 |
30篇 | |
中国医学 | 645篇 |
肿瘤学 | 5125篇 |
出版年
2024年 | 212篇 |
2023年 | 1602篇 |
2022年 | 2370篇 |
2021年 | 3684篇 |
2020年 | 3445篇 |
2019年 | 3210篇 |
2018年 | 3055篇 |
2017年 | 2933篇 |
2016年 | 2948篇 |
2015年 | 2683篇 |
2014年 | 4668篇 |
2013年 | 5718篇 |
2012年 | 3616篇 |
2011年 | 3916篇 |
2010年 | 2920篇 |
2009年 | 2945篇 |
2008年 | 2925篇 |
2007年 | 2803篇 |
2006年 | 2473篇 |
2005年 | 2288篇 |
2004年 | 1907篇 |
2003年 | 1648篇 |
2002年 | 1361篇 |
2001年 | 1174篇 |
2000年 | 917篇 |
1999年 | 777篇 |
1998年 | 714篇 |
1997年 | 574篇 |
1996年 | 470篇 |
1995年 | 486篇 |
1994年 | 420篇 |
1993年 | 422篇 |
1992年 | 387篇 |
1991年 | 331篇 |
1990年 | 231篇 |
1989年 | 223篇 |
1988年 | 229篇 |
1987年 | 165篇 |
1986年 | 147篇 |
1985年 | 201篇 |
1984年 | 153篇 |
1983年 | 84篇 |
1982年 | 120篇 |
1981年 | 80篇 |
1980年 | 76篇 |
1979年 | 44篇 |
1978年 | 47篇 |
1977年 | 43篇 |
1976年 | 19篇 |
1975年 | 12篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
Tape stripping of human stratum corneum yields cell layers that originate from various depths because of furrows in the skin 总被引:2,自引:0,他引:2
R. G. van der Molen F. Spies J. M. van ‘t Noordende E. Boelsma A. M. Mommaas H. K. Koerten 《Archives of dermatological research》1997,289(9):514-518
Received: 21 November 1996 相似文献
132.
The guinea pig maximization test (GPMT) of Magnusson and Kligman was published in 1969. Since then, a vast body of practical experience with the test has been accumulated. New information requires that certain aspects of the procedure be reevaluated, especially with regard to the interpretation of challenge results. In particular, awareness of the phenomenon of hyperirritable skin (the 'angry back' phenomenon) suggests that presently used controls are not always adequate and may overstate allergenicity owing to false-positive reactions. The control group should be exposed to a chemical insult at induction which provokes an inflammatory reaction comparable to the test substance. We present strategies to distinguish irritant from allergic responses. Allergic reactions should persist on rechallenge weeks later, while nonspecific irritant reactions generally fade and are irreproducible in particular animals. Finally, when a chemical is identified as a contact sensitizer of risk is necessary to estimate the relevance of the test result to usage in the real world. 相似文献
133.
Comorbidity and social phobia: evidence from clinical,epidemiologic, and genetic studies 总被引:3,自引:0,他引:3
Kathleen Ries Merikangas Jules Angst 《European archives of psychiatry and clinical neuroscience》1995,244(6):297-303
This paper reviews evidence from clinical, epidemiologic, and family studies regarding the association between social phobia and other syndromes. Social phobia is strongly associated with other anxiety disorders, substance abuse, and affective disorders in both clinical and community samples. An average of 80% of social phobics identified in community samples meet diagnostic criteria for another lifetime condition. Social phobia is most strongly associated with other subtypes of anxiety disorders, with an average of 50% of social phobics in the community reporting a concomitant anxiety disorder including another phobic disorder, generalized anciety, or panic disorder. Approximately 20% of subjects in the community meet lifetime criteria for a major depressive disorder. The onset of social phobia generally precedes that of all other disorders, with the exception of simple phobia. Both clinical severity and treated prevalence are consistently greater among social phobics with comorbid disorders The results of family and twin studies reveal that shared etiologic factors explain a substantial proportion of the comorbidity between social phobia and depression, whereas the association between social phobia and alcoholism derives from a nonfamilial causal relationship between the two conditions. Clinical and phenomenologic implications of these findings are discussed. 相似文献
134.
颈淋巴结清扫手术后乳糜漏的处理 总被引:10,自引:0,他引:10
目的 :探讨颈淋巴结清扫手术后乳糜漏的处理方法。方法 :回顾分析颈淋巴结清扫手术 12 85例术后发生乳糜漏 2 1例的临床资料。结果 :乳糜漏的发生率为 1.6 % ,18例经保守治疗治愈 ,3例经再次手术治愈。结论 :对颈淋巴结清扫术后的乳糜漏应及早诊断 ,术中应加强预防并及时处理 相似文献
135.
136.
137.
探刊干性型老年黄斑变性(age-related macular deganeration,AMD)的病变发展特征并 寻找监测AMD病情进展的较敏感指标。
方法:用眼底彩色照相和眼底荧光血管造影(FFA)、明视视网膜电囤(ERG)、FM100-hue 色彩试验及视力检查,对60例(111眼)50~80岁、视力≤1.0的干性型AMD患者进行3~74个月(平均30.2个月)的随访观察。
结果:本组68眼经FFA检查、平均25.6个月随访,其中25%的患眼病灶损害有快慢不一的发展.全部111眼视力在平均30.2个月随访中有18%患眼的视力下降2行以下,且与病灶进展相符,FM100-hue 色彩试验的被随访者中,随访2年以后,其总错误分明显的增加(P<0.01).63眼的明视ERG在随访过程中无明显变化。
结论:大部分干性AMD患眼的病灶损害和视力可以在较长时间内维持稳定。FM100—hue的总错误分可能为监测AMD病情进展的较敏感指标.
(中华眼底病杂志,1997,13:150-152) 相似文献
138.
抗—HCV阳性单采浆供血员HGV感染随访研究 总被引:3,自引:0,他引:3
为了解单采浆供血员庚型肝炎病毒(HGV)感染及其转归,对102名抗-HCV阳性单采浆供血员冻存血清进行抗-HGV和HGVRNA检测,对抗-HGV和(或)HGVRNA阳性者作3年随访研究。采用EIA法检测抗-HGV,包被抗原来自HGV不同功能区的合成肽。应用RT-PCR法检测HGVRNA,引物选自HGVNS3区。结果表明,抗-HCV阳性单采浆供血员HGVRNA阳性率为19.61%(20/102),抗-HGV阳性率为17.65%(18/102),HGV感染率(抗HGV和/或HGVRNA阳性)为24.51%(25/102),而对照组仅为0.94%(1/106)。提示单采血浆是HGV感染的重要危险因素。HGVRNA和抗-HGV的3年阴转率分别为35.00%(7/20)和11.11%(2/18),说明HGV感染有慢性携带趋势 相似文献
139.
The effects of MPP+ (2.5–20 mg/kg) on the adrenal glands and heart were investigated in rats. At various periods after s.c. drug administration the rats were decapitated and tissue catecholamine levels were determined by means of HPLC with electrochemical detection. Adrenal dopamine (DA) levels were reduced at 2–8 h after MPP+ administration, but this decrease was followed by an elevation after 16 h and return to the control values after one week. Three successive injections of MPP+ caused a statistically significant elevation in adrenal DA, one day, with a tendency to elevation four and seven days after the last injection, whereas a severe (up to 96%) decrease in heart noradrenaline (NA) was found one day after the last injection. Seven days after the last injection a 50% depletion of NA in the heart was still observed. Pretreatment with GBR 12909 (30 mg/kg, 4 h) blocked the MPP+ (10 mg/kg, 2 h) induced reduction of adrenal DA levels, but at the same time GBR 12909 failed to block the effects of MPP+ in the heart. One day after three successive daily injections of MPP+ (10 mg/kg each), the DA-uptake inhibitor GBR 12909 (30 mg/kg, 6 h) could still induce an increase in adrenal DA.MPP+ appears to lack persistent cytotoxic action in the adrenal medulla but rather to cause a transient inhibition of DA synthesis followed by a compensatory stimulation. The inhibition can be blocked by specific inhibitor of the DA-uptake mechanism, suggesting a direct effect of MPP+ taken up by adrenomedullary cells. The data obtained so far do not suggest any involvement of peripheral dopaminergic nerves in the action of MPP+ on the adrenal medulla. The long-lasting depletion of the heart NA, however, suggests a lesion of peripheral noradrenergic nerves.Part of this work was presented at 6th International Symposium on Chromaffin Cell Biology, Marburg, Germany, 18–23 August 1991
Correspondence to: M. Kujacic at the above address 相似文献
140.
家禽加工流水线作业工人颈肩腕疾患的调查 总被引:1,自引:0,他引:1
对149名家禽加工厂作业女工的颈肩腕疾患进行了调查。结果表明:观察组职业性颈肩腕疾患OCD,(肩周炎、尺管综合征、腕管综合征、腱鞘炎、肱骨内外髁炎)的总发生率为39.60%,与对照组相比差异有非常显著意义(P<0.01),其发生率与工龄、年龄及工种别有关。我们认为OCD发生的职业危险因素主要是上肢反复用力活动、静力作业、不合理的操作姿势,而且低温、高温的作业环境对OCD的发生也起到一定的促进作用。 相似文献