全文获取类型
收费全文 | 7463篇 |
免费 | 428篇 |
国内免费 | 32篇 |
专业分类
耳鼻咽喉 | 76篇 |
儿科学 | 282篇 |
妇产科学 | 171篇 |
基础医学 | 695篇 |
口腔科学 | 178篇 |
临床医学 | 575篇 |
内科学 | 1671篇 |
皮肤病学 | 173篇 |
神经病学 | 489篇 |
特种医学 | 222篇 |
外科学 | 1559篇 |
综合类 | 118篇 |
一般理论 | 2篇 |
预防医学 | 283篇 |
眼科学 | 232篇 |
药学 | 621篇 |
中国医学 | 34篇 |
肿瘤学 | 542篇 |
出版年
2024年 | 6篇 |
2023年 | 76篇 |
2022年 | 169篇 |
2021年 | 380篇 |
2020年 | 208篇 |
2019年 | 264篇 |
2018年 | 364篇 |
2017年 | 233篇 |
2016年 | 286篇 |
2015年 | 258篇 |
2014年 | 405篇 |
2013年 | 451篇 |
2012年 | 737篇 |
2011年 | 691篇 |
2010年 | 386篇 |
2009年 | 353篇 |
2008年 | 419篇 |
2007年 | 442篇 |
2006年 | 375篇 |
2005年 | 321篇 |
2004年 | 239篇 |
2003年 | 184篇 |
2002年 | 145篇 |
2001年 | 38篇 |
2000年 | 39篇 |
1999年 | 35篇 |
1998年 | 28篇 |
1997年 | 25篇 |
1996年 | 21篇 |
1995年 | 18篇 |
1994年 | 14篇 |
1993年 | 15篇 |
1992年 | 39篇 |
1991年 | 31篇 |
1990年 | 17篇 |
1989年 | 18篇 |
1988年 | 15篇 |
1987年 | 20篇 |
1986年 | 15篇 |
1985年 | 25篇 |
1984年 | 12篇 |
1983年 | 11篇 |
1982年 | 5篇 |
1981年 | 8篇 |
1979年 | 15篇 |
1978年 | 10篇 |
1977年 | 11篇 |
1976年 | 5篇 |
1975年 | 6篇 |
1974年 | 8篇 |
排序方式: 共有7923条查询结果,搜索用时 31 毫秒
81.
82.
Pashtoon Murtaza Kasi Faisal Shahjehan Jordan J. Cochuyt Zhuo Li Dorin Toma Colibaseanu Amit Merchea 《Clinical colorectal cancer》2019,18(1):e87-e95
Background
Recent trends have identified increasing number of young individuals with rectal and colon cancers. These individuals, who are younger than 50 years old, in most instances would not meet screening guidelines. We aimed to report the characteristics and trend of the rising proportion of young individuals being diagnosed with rectal and colon cancers at our institutions.Patients and Methods
This study included 3381 rectal and colon cancer patients from the Mayo Clinic cancer registry from 1972 to 2017 who were diagnosed with rectal or colon cancer and who were < 50 years old. Patient and cancer characteristics are described. The Cochran-Armitage trend test was used to see if the change in percentage diagnosed at age < 50 years had a significant trend over the years. A linear regression model was fit to estimate the percentage change per year when the trend was approximately linear.Results
The percentage of patients diagnosed with rectal or colon cancer in different age categories over the years showed a rising trend for individuals aged < 50. Most of these tumors were distal (rectum, left-sided colon, and right-sided colon were 49.8%, 28.8%, and 21.4%, respectively). This was more so for patients < 50 diagnosed with rectal cancer, which showed a linear increase at a rate of 0.26% per year (P < .001).Conclusion
Our study affirms the rising proportion of colorectal cancers found in young individuals, with a linear ongoing rise of rectal cancers in particular. This may have implications for the current screening recommendations for colorectal cancers, which are already being revised. 相似文献83.
Richard Rothenberg Scott R. Weaver Dajun Dai Christine Stauber Amit Prasad Megumi Kano 《Journal of urban health》2014,91(5):823-835
Available urban health metrics focus primarily on large area rankings. Less has been done to develop an index that provides information about level of health and health disparities for small geographic areas. Adopting a method used by the Human Development Index, we standardized indicators for small area units on a (0, 1) interval and combined them using their geometric mean to form an Urban Health Index (UHI). Disparities were assessed using the ratio of the highest to lowest decile and measurement of the slope of the eight middle deciles (middle; 80 %) of the data. We examined the sensitivity of the measure to weighting, to changes in the method, to correlation among indicators, and to substitution of indicators. Using seven health determinants and applying these methods to the 128 census tracts in the city of Atlanta, USA, we found a disparity ratio of 5.92 and a disparity slope of 0.54, suggesting substantial inequality and heterogeneity of risk. The component indicators were highly correlated; their systematic removal had a small effect on the results. Except in extreme cases, weighting had a little effect on the rankings. A map of Atlanta census tracts exposed a swath of high disparity. UHI rankings, ratio, and slope were resistant to alteration in composition and to non-extreme weighting schemes. This empirical evaluation was limited to a single realization, but suggests that a flexible tool, whose method rather than content is standardized, may be of use for local evaluation, for decision making, and for area comparison. 相似文献
84.
85.
86.
87.
88.
89.
The utilization of impedance technology has enhanced our understanding and assessment of esophageal dysmotility. Esophageal high-resolution manometry (HRM) catheters incorporated with multiple impedance electrodes help assess esophageal bolus transit, and the combination is termed high-resolution impedance manometry (HRIM). Novel metrics have been developed with HRIM—including esophageal impedance integral ratio, bolus flow time, nadir impedance pressure, and impedance bolus height—that augments the assessment of esophageal bolus transit. Automated impedance-manometry (AIM) analysis has enhanced understanding of the relationship between bolus transit and pressure phenomena. Impedance-based metrics have improved understanding of the dynamics of esophageal bolus transit into four distinct phases, may correlate with symptomatic burden, and can assess the adequacy of therapy for achalasia. An extension of the use of impedance involves impedance planimetry and the functional lumen imaging probe (FLIP), which assesses esophageal biophysical properties and distensibility, and could detect patterns of esophageal contractility not seen on HRM. Impedance technology, therefore, has a significant impact on esophageal function testing in the present day. 相似文献
90.
Asit Arora H. H. Nag Abhishek Yadav Shaleen Agarwal Amit Javed Anil K. Agarwal 《The Indian journal of surgery》2015,77(2):99-103
Postcholecystectomy bile duct injuries are a cause of significant morbidity and occasional mortality. Intraoperative recognition and repair of complete biliary transection with hepaticojejunostomy is the recommended treatment; however, it is possible only in few patients as either the injury is not recognized intraoperatively or the center is not geared up to perform an urgent hepaticojejunostomy in these patients with a nondilated duct. Retrospective analysis of data from a tertiary care referral center over a period of 10 years from January 2000 to December 2009 to report the feasibility and outcomes of prompt repair was done (defined as repair within 72 h of index operation) of postcholecystectomy bile duct injury. Ten patients of postcholecystectomy bile duct injury detected intraoperatively and referred early underwent prompt repair. All patients had a complete transection of the bile duct (type of injuries as per Strasberg classification: Type E V: 1, Type E III: 5, Type E II: 3 and Type E I: 1). The mean duration between injury and bile duct repair in the form of Roux-en-Y hepaticojejunostomy (RYHJ) was 22.7 (range 5–42) hours. The mean diameter of the anastomosis was 1.63 (range1–2.1) cm, and the anastomosis was stented in 7 patients. The mean duration of surgery was 4.6 +1.7 h. One patient developed bile leak on the first postoperative day, which settled by day 5. The mean duration of hospital stay was 5.1 (range 4–8) days. With a mean follow-up of 42 (range 24–110) months, all patients had excellent (70 %) or good outcome (30 %). Prompt RYHJ (within first 72 h) for postcholecystectomy biliary transection is an effective treatment and potentially limits the morbidity to the patient. 相似文献