全文获取类型
收费全文 | 246785篇 |
免费 | 15246篇 |
国内免费 | 683篇 |
专业分类
耳鼻咽喉 | 3137篇 |
儿科学 | 9075篇 |
妇产科学 | 6167篇 |
基础医学 | 33498篇 |
口腔科学 | 5230篇 |
临床医学 | 21412篇 |
内科学 | 49487篇 |
皮肤病学 | 4893篇 |
神经病学 | 21562篇 |
特种医学 | 9107篇 |
外国民族医学 | 33篇 |
外科学 | 38394篇 |
综合类 | 3530篇 |
现状与发展 | 1篇 |
一般理论 | 197篇 |
预防医学 | 17351篇 |
眼科学 | 6834篇 |
药学 | 17263篇 |
1篇 | |
中国医学 | 604篇 |
肿瘤学 | 14938篇 |
出版年
2021年 | 3112篇 |
2020年 | 1929篇 |
2019年 | 3203篇 |
2018年 | 3915篇 |
2017年 | 2981篇 |
2016年 | 3600篇 |
2015年 | 4136篇 |
2014年 | 5812篇 |
2013年 | 8266篇 |
2012年 | 12013篇 |
2011年 | 12702篇 |
2010年 | 7209篇 |
2009年 | 6789篇 |
2008年 | 11646篇 |
2007年 | 12437篇 |
2006年 | 12081篇 |
2005年 | 12201篇 |
2004年 | 11687篇 |
2003年 | 10931篇 |
2002年 | 10631篇 |
2001年 | 8406篇 |
2000年 | 8037篇 |
1999年 | 7254篇 |
1998年 | 3174篇 |
1997年 | 2871篇 |
1996年 | 2349篇 |
1995年 | 2216篇 |
1994年 | 1966篇 |
1993年 | 1956篇 |
1992年 | 4591篇 |
1991年 | 4337篇 |
1990年 | 4245篇 |
1989年 | 3964篇 |
1988年 | 3595篇 |
1987年 | 3478篇 |
1986年 | 3348篇 |
1985年 | 3227篇 |
1984年 | 2593篇 |
1983年 | 2192篇 |
1982年 | 1675篇 |
1981年 | 1567篇 |
1980年 | 1343篇 |
1979年 | 2253篇 |
1978年 | 1762篇 |
1977年 | 1499篇 |
1976年 | 1270篇 |
1975年 | 1492篇 |
1974年 | 1538篇 |
1973年 | 1525篇 |
1972年 | 1309篇 |
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
101.
Joe Jacob Shibhu George B. R. Suchit Roy P. U. Rajesh 《Indian journal of otolaryngology and head and neck surgery》2006,58(1):76-77
Malignancy larynx usually presents early, the common symptoms being hoarseness, pain thorat, cough and irritation of throat. An advanced malignancy is likely to be complicated by a pharyngo-cutaneous fistula. However it is an occurrence towards the end stage of the disease. Here we present a case of malignancy larynx primarily presenting as pharyngo-cutaneous fistula without any other symptoms. 相似文献
102.
目的:直肠腺瘤和其他疑似为良性的病变应用经肛门内镜切除术并未普及。该项研究旨在评估经肛门内镜切除术的效能和安全性。方法:回顾性研究分析在1993-2004年之间3所斯德哥尔摩医院中经肛门内镜切除术的患,内容包括患自身及病变特性、并发症、随访时间和复发率。结果:180例中共131例行经肛门内镜切除术。160例经组织学诊断为腺瘤,12例为癌瘤,其余8例分别为增生、纤维化或正常黏膜。直肠腺瘤患中,77例仅行单次经肛门内镜切除术,16例因巨大腺瘤而多次行该手术,27例因复发而需另行经肛门内镜切除术或其他手术。中位复发时间为7个月,但未出现直肠癌。16例手术患出现并发症。2例患必须行Hartman手术,1例因肠穿孔,另1例因出血。手术期间无死亡。未复发的中位随访期为32个月(极差0—67)。[编按] 相似文献
103.
104.
S Chinn S H Downs J M Anto M W Gerbase B Leynaert R de Marco C Janson D Jarvis N Künzli J Sunyer C Svanes E Zemp U Ackermann-Liebrich P Burney 《The European respiratory journal》2006,28(4):763-771
The incidence of asthma has been reported to be associated with obesity. An alternative analysis, of net change in prevalence, does not require exclusion of those with asthma at baseline. Follow-up data were obtained from 9,552 participants in the European Community Respiratory Health Survey and the Swiss cohort Study on Air Pollution and Lung Disease in Adults. Incidence of asthma was analysed by proportional hazards regression, and net changes in symptoms and asthma status by generalised estimating equations, by obesity group. Incidence and net change in ever having had asthma were greater in females than in males, and in participants who remained obese compared with those who were never obese (hazard ratio 2.00, 95% confidence interval 1.25-3.20; excess net change 2.8%, 0.4-5.3% per 10 yrs). The effect of being obese on net change in diagnosed asthma was greater in females than in males, but for net change in wheeze without a cold it was greater in males. The present results are consistent with asthma being more frequently diagnosed in females, especially obese females. These findings may help to explain the reports of a stronger association between asthma and obesity in females than in males. 相似文献
105.
Matthew S Lewis Paul Maruff Brendan S Silbert Lis A Evered David A Scott 《Archives of clinical neuropsychology》2006,21(5):421-427
The reliable change index (RCI) expresses change relative to its associated error, and is useful in the identification of post-operative cognitive dysfunction (POCD). This paper examines four common RCIs that each account for error in different ways. Three rules incorporate a constant correction for practice effects and are contrasted with the standard RCI that had no correction for practice. These rules are applied to 160 patients undergoing coronary artery bypass graft (CABG) surgery who completed neuropsychological assessments preoperatively and 1 week post-operatively using error and reliability data from a comparable healthy non-surgical control group. The rules all identify POCD in a similar proportion of patients, but the use of the within subject standard deviation, expressing the effects of random error, as an error estimate is a theoretically appropriate denominator when a constant error correction, removing the effects of systematic error, is deducted from the numerator in a RCI. 相似文献
106.
Mohammad-Reza Movahed John Vu Paul Lizotte 《Cardiovascular Revascularization Medicine》2006,7(4):250-254
We present a patient with a history of coronary artery disease and exertional angina after an acute anterior myocardial infarction. Angiography and ventriculography revealed multivessel coronary artery disease and a large apical aneurysm. Echocardiography and gated SPECT studies were performed for further evaluation of ischemia and assessment of left ventricular function. Gated SPECT and echocardiography failed to detect a large apical aneurysm due to a hyperdynamic left ventricular wall at the neck of the aneurysm. This case demonstrates the importance of using multiple imaging modalities in the evaluation of ventricular function in the setting of coronary artery disease. 相似文献
107.
Henk R Franke F Froukje Snaaijer Paul W H Houben Marius J van der Mooren 《Gynecological endocrinology》2006,22(12):692-697
OBJECTIVE: To assess the effects of adding combined estradiol/norethisterone acetate therapy (CENT) to goserelin acetate treatment (GA) of dysfunctional uterine bleeding (DUB) in perimenopausal women. METHODS: In a randomized, placebo-controlled, double-blind trial followed by an open follow-up study, 31 perimenopausal women with DUB were recruited from gynecological outpatient departments of two Dutch hospitals and randomized for treatment with either GA/placebo or GA/CENT for 6 months followed by 18 months of GA/CENT for all. The main outcome measures were abdominal pain, number of bleeding days, double-layer endometrial thickness (DET), Greene climacteric score (GCS), visual analog scale for well-being, bone mineral density (BMD) and mammographic density (BI-RAD score). RESULTS: Abdominal pain, number of bleeding days and DET decreased in both groups, the between-group difference in decrease not being statistically significant. GCS initially showed significant improvement in the GA/CENT group. BMD decreased significantly in the GA/placebo group (-4.1%) compared with the GA/CENT group (-0.3%). Another 18 months of GA/CENT did not result in a lasting difference in BMD between groups. BI-RAD scores did not differ significantly between or within the two groups. CONCLUSIONS: Adding CENT to GA treatment for DUB in perimenopausal women initially prevented BMD loss and improved climacteric complaints, while having no negative impact on vaginal bleeding, abdominal pain or BI-RAD scores. However, prolonged treatment did not result in a lasting prevention of bone loss. 相似文献
108.
M. RAUVALA K. AGLUND† U. PUISTOLA T. TURPEENNIEMI-HUJANEN‡ G. HORVATH§ R. WILLÉN & U. STENDAHL† 《International journal of gynecological cancer》2006,16(3):1297-1302
The incidence of uterine cervical cancer has increased slightly in Western countries, with an increase in relatively young women. Overexpression of matrix metalloproteinases (MMPs)-2 and -9 has turned out as a prognostic factor in many cancers. We compared the expression of the proteins MMP-2 and MMP-9 in cervical primary tumors with clinical outcome and risk factors of cervical cancer. One hundred sixty-one patients with cervical cancer treated in Ume? University Hospital or Sahlgrenska University Hospital, Sweden, between 1991 and 1995 were included in the study. Paraffin-embedded tissue samples obtained prior to treatment were examined immunohistochemically by specific antibodies for MMP-2 and MMP-9. Forty-two percent of the tumors were intensively positive for MMP-2 and 31% for MMP-9. Nineteen percent of the samples were intensively positive for both proteinases and 47% negative or weak for both. Overexpression of MMP-2 seemed to predict unfavorable survival under Kaplan-Meier analysis and in the multivariate analysis. Early sexual activity and low parity seemed to correlate to overexpression of MMP-2. MMP-9 was not associated with survival or sexual behavior. Intensive MMP-9 was noted in grade 1 tumors. We conclude that MMP-2 and MMP-9 have different roles in uterine cervical cancer. MMP-2 could be associated with aggressive behavior, but MMP-9 expression diminishes in high-grade tumors. 相似文献
109.
110.