全文获取类型
收费全文 | 37730篇 |
免费 | 3662篇 |
国内免费 | 842篇 |
专业分类
耳鼻咽喉 | 400篇 |
儿科学 | 734篇 |
妇产科学 | 403篇 |
基础医学 | 3760篇 |
口腔科学 | 1300篇 |
临床医学 | 4802篇 |
内科学 | 6604篇 |
皮肤病学 | 694篇 |
神经病学 | 2024篇 |
特种医学 | 1641篇 |
外科学 | 4721篇 |
综合类 | 3962篇 |
现状与发展 | 5篇 |
一般理论 | 24篇 |
预防医学 | 4028篇 |
眼科学 | 517篇 |
药学 | 3600篇 |
23篇 | |
中国医学 | 1192篇 |
肿瘤学 | 1800篇 |
出版年
2023年 | 277篇 |
2022年 | 567篇 |
2021年 | 909篇 |
2020年 | 649篇 |
2019年 | 598篇 |
2018年 | 605篇 |
2017年 | 613篇 |
2016年 | 554篇 |
2015年 | 879篇 |
2014年 | 1169篇 |
2013年 | 1602篇 |
2012年 | 2228篇 |
2011年 | 2349篇 |
2010年 | 1760篇 |
2009年 | 1593篇 |
2008年 | 2105篇 |
2007年 | 2025篇 |
2006年 | 1957篇 |
2005年 | 1795篇 |
2004年 | 1498篇 |
2003年 | 1445篇 |
2002年 | 1282篇 |
2001年 | 1229篇 |
2000年 | 1241篇 |
1999年 | 918篇 |
1998年 | 327篇 |
1997年 | 287篇 |
1996年 | 269篇 |
1995年 | 287篇 |
1994年 | 229篇 |
1993年 | 222篇 |
1992年 | 618篇 |
1991年 | 640篇 |
1990年 | 590篇 |
1989年 | 529篇 |
1988年 | 501篇 |
1987年 | 496篇 |
1986年 | 487篇 |
1985年 | 482篇 |
1984年 | 346篇 |
1983年 | 304篇 |
1982年 | 226篇 |
1981年 | 208篇 |
1979年 | 325篇 |
1978年 | 240篇 |
1977年 | 201篇 |
1974年 | 214篇 |
1973年 | 206篇 |
1971年 | 192篇 |
1970年 | 170篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
Microbial identification by gas chromatography 总被引:1,自引:0,他引:1
M A White M D Simmons A Bishop H A Chandler 《Journal of the Royal Naval Medical Service》1988,74(3):141-146
92.
D M Floyd S D Kimball J Krapcho J Das C F Turk R V Moquin M W Lago K J Duff V G Lee R E White 《Journal of medicinal chemistry》1992,35(4):756-772
As part of a program to discover potent antihypertensive analogues of diltiazem (3a), we prepared 1-benzazepin-2-ones (4). Benzazepinones competitively displace radiolabeled diltiazem, and show the same absolute stereochemical preferences at the calcium channel receptor protein. Derivatives of 4 containing a trifluoromethyl substituent in the fused aromatic ring show potent and long-acting antihypertensive activity. Studies of the metabolism of 4 lead to the metabolically stable antihypertensive calcium channel blockers 5a and 5c. Benzazepinone 5a is a longer acting and more potent antihypertensive agent than the second generation diltiazem analogue TA-3090 (3e). 相似文献
93.
Standard models for the analysis of repeated measurements assume a common response profile for all experimental units within a treatment group. However, in many applications this under-represents the nature of the response. There may be several distinct modes of response within a group (for example, responders versus non-responders to a given treatment), or there may be a set of distinct response profiles which are common to all the treatment groups. In these situations the effect of treatment can be characterized both by the shape of the fitted profiles and by estimating the proportion of cases who exhibit each particular response profile. This paper describes how such experiments may be analysed through the introduction of a latent variable into the standard model. Maximum likelihood estimation is straight-forward using the EM algorithm. Model choice requires some care, but good-fitting models can be identified via inspection of residuals and the use of empirical semi-variogram plots. Once the number of distinct profiles has been determined, treatment effects can be investigated using likelihood-ratio statistics. The approach is illustrated with a re-analysis of a dataset first described by Grizzle and Allen. 相似文献
94.
95.
<正> 患者男性,52岁,突发上腹痛6 h来诊。疼痛呈持续性,无放射痛,无呕吐、腹泻、黄疸。既往有胃溃疡病史。查体:神清,T37.8℃,痛苦面容,平卧位,巩膜皮肤无黄染,心肺(-),上腹部压痛,轻度肌卫,无反跳痛,肝浊音界存在,移动性浊音(-),肠鸣音减弱。化验:WBC12.0×10~9/L、中性0.87。腹 相似文献
96.
Lorna M Gillespie Simon D White Sunil K Sinha Steven M Donn 《Journal of perinatology》2003,23(3):205-207
OBJECTIVE: We performed a prospective, randomized clinical trial to compare the usefulness of the minute ventilation test (MVT) with clinical judgement in predicting readiness for extubation in preterm newborns with respiratory distress syndrome requiring surfactant therapy and mechanical ventilation. STUDY DESIGN: A total of 42 preterm infants with respiratory distress syndrome were randomized when they reached preselected ventilator settings. The primary outcome measure was the time from study entry to extubation, provided the infant remained extubated for at least 24 hours. RESULTS: Infants evaluated by the MVT were extubated in a significantly shorter period of time (mean of 8 hours) than those evaluated clinically (mean of 36 hours). The extubation failure rate was similar in the two groups. CONCLUSION: The MVT is an easily performed objective measure that can be used to predict readiness for extubation in preterm infants. In this study, it significantly shortened the time for extubation and was not associated with a higher rate of reintubation. 相似文献
97.
年龄小于45岁原发性慢性闭角型青光眼的显微手术治疗 总被引:1,自引:0,他引:1
目的探讨原发性慢性闭角型青光眼年轻患者临床治疗的经验和体会。方法对临床收治的41例52眼、年龄〈45岁、临床确诊为进展期或晚期原发性慢性闭角型青光眼的病例进行抗青光眼显微手术处理的病例进行回顾性分析。结果随访时间平均(32.50±5.08)个月;男16例,女25例;进展期28眼,晚期24眼;52眼均行抗青光眼手术-复合式小梁切除手术治疗;眼轴长平均(22.40±1.63)mm,其中〈21mm占17.31%,小眼球占13.46%;前房深度平均(1.90±0.39)mm,其中〈1.9mm占61.46%;超声生物显微镜检查高褶虹膜构型占59.62%,其中睫状突位置靠前者10眼;术前平均眼压(41.73±12.26)mmHg,末次术后平均眼压(12.03±4.57)mmHg,术前后眼压差异有统计学意义(t=3.520,P〈0.001)。术后并发症主要有浅前房,恶性青光眼。恶性青光眼手术处理方式包括玻璃体抽液、前段玻璃体切割以及超声乳化白内障吸除加人工晶状体植入术治疗。4眼因眼压控制不理想,行二次抗青光眼手术治疗。结论年轻原发性慢性闭角型青光眼患者,女性多见,多伴有眼轴短、前房浅等特点,抗青光眼复合式小梁手术治疗要注意防治术后浅前房、恶性青光眼的发生。术前详细检查、手术操作精细以及有效处理术后并发症将有助于提高手术成功率和减少并发症。 相似文献
98.
99.
This report aims to encourage optometrists to reflect on the legal implications of clinical contact lens practice, with particular reference to the practice of orthokeratology (ortho-k), which has seen a recent revival of interest. A patient may claim compensation if an optometrist is negligent by breaching his duty to exercise reasonable care and skill in diagnosis, advice or treatment. However, the optometrist will only be liable for reasonably foreseeable harm to the patient, so practitioners need to be fully aware of the foreseeable risks. Failure to adequately inform the patient may lead to a claim for negligence, if disclosure of the risks would have influenced the patient's decision to undergo or forego the procedure. It is important that the professional bodies establish guidelines on acceptable practice, with particular emphasis on the provision of information to patients. Reasonable disclosure, use of appropriate information/consent forms, and proper documentation of cases, should all focus on the needs of, and benefits to, patients. 相似文献
100.
肌病肾病代谢综合征治疗进展 总被引:1,自引:0,他引:1
肌病肾病代谢综合征是急性动脉阻塞致骨骼肌溶解的严重并发症。积极治疗原发病,及早补液扩容、碱化尿液、早期血液净化治疗是降低截肢率、病死率的关键。本文就肌病肾病代谢综合征治疗进展作一综述。 相似文献