全文获取类型
收费全文 | 3307篇 |
免费 | 199篇 |
国内免费 | 74篇 |
专业分类
耳鼻咽喉 | 49篇 |
儿科学 | 37篇 |
妇产科学 | 55篇 |
基础医学 | 199篇 |
口腔科学 | 48篇 |
临床医学 | 376篇 |
内科学 | 386篇 |
皮肤病学 | 10篇 |
神经病学 | 154篇 |
特种医学 | 107篇 |
外科学 | 764篇 |
综合类 | 347篇 |
预防医学 | 397篇 |
眼科学 | 13篇 |
药学 | 213篇 |
1篇 | |
中国医学 | 16篇 |
肿瘤学 | 408篇 |
出版年
2024年 | 8篇 |
2023年 | 57篇 |
2022年 | 124篇 |
2021年 | 148篇 |
2020年 | 136篇 |
2019年 | 143篇 |
2018年 | 157篇 |
2017年 | 113篇 |
2016年 | 129篇 |
2015年 | 130篇 |
2014年 | 264篇 |
2013年 | 238篇 |
2012年 | 213篇 |
2011年 | 190篇 |
2010年 | 138篇 |
2009年 | 178篇 |
2008年 | 150篇 |
2007年 | 154篇 |
2006年 | 137篇 |
2005年 | 84篇 |
2004年 | 89篇 |
2003年 | 49篇 |
2002年 | 57篇 |
2001年 | 53篇 |
2000年 | 38篇 |
1999年 | 38篇 |
1998年 | 46篇 |
1997年 | 32篇 |
1996年 | 28篇 |
1995年 | 17篇 |
1994年 | 18篇 |
1993年 | 21篇 |
1992年 | 23篇 |
1991年 | 12篇 |
1990年 | 18篇 |
1989年 | 17篇 |
1988年 | 11篇 |
1987年 | 13篇 |
1986年 | 12篇 |
1985年 | 18篇 |
1984年 | 9篇 |
1983年 | 8篇 |
1982年 | 6篇 |
1981年 | 7篇 |
1980年 | 11篇 |
1979年 | 9篇 |
1978年 | 10篇 |
1977年 | 6篇 |
1975年 | 4篇 |
1973年 | 3篇 |
排序方式: 共有3580条查询结果,搜索用时 15 毫秒
1.
2.
This paper estimates the causal impact of retirement on the Body Mass Index (BMI) of adults aged 50–69 years old, on the probability of being either overweight or obese and on the probability of being obese. Based on the 2004, 2006 and 2010–2011 waves of the Survey of Health, Ageing and Retirement in Europe (SHARE), our identification strategy exploits variation in European Early Retirement Ages (ERAs) and stepwise increases in ERAs in Austria and Italy between 2004 and 2011 to examine an exogenous shock to retirement behavior. Our results show that retirement induced by discontinuous incentives in early retirement schemes causes a 12-percentage point increase in the probability of being obese among men within a two- to four-year period. We find that the impact of retirement is highly non-linear and mostly affects the right-hand side of the male BMI distribution. Additional results show that this pattern is driven by men retiring from strenuous jobs and by those who were already at risk of obesity. In contrast, no significant results are found among women. 相似文献
3.
《Clinics in plastic surgery》2019,46(4):625-639
4.
5.
Mohammad K. Jamal M.D. Eric J. DeMaria M.D. Jason M. Johnson D.O. Brennan J. Carmody M.D. Luke G. Wolfe M.S. John M. Kellum M.D. Jill G. Meador R.N. 《Surgery for obesity and related diseases》2006,2(2):417-127
BACKGROUND: Preoperative dietary counseling (PDC) before bariatric surgery is mandated by a growing number of insurance payers. Their claim is that PDC improves outcomes and postoperative compliance. We compared outcomes of GBP patients undergoing a mandatory 13 weeks of PDC (n = 72) to a contemporaneous group of patients with no such requirement (no-PDC; n = 252) who underwent operation between January 2000 and December 2002. METHODS: The PDC and no-PDC groups were characterized by similar male:female ratios (1:4 vs 1:4.6), mean age (42 years), mean body weight (324 lb vs 309 lb), and mean body mass index (BMI) (52 kg/m2 vs 50 kg/m2). The PDC group had a higher incidence of obstructive sleep apnea compared with the no-PDC group (41% vs 28%; P < .04) but otherwise the two groups had similar incidences of obesity-related comorbidities. The presurgery dropout rate was 50% higher in the PDC group than in the no-PDC group (28% vs 19%; P < .05). RESULTS: At 1 year follow-up, the no-PDC patients had a statistically greater percentage excess weight loss (67% vs 60%; P < .0001), lower BMI (32 vs 35; P < .015), and lower body weight (197 vs 218; P < .01). Resolution of major comorbidities, complication rates, 30-day postoperative mortality, and postoperative compliance with follow-up were similar in the two groups. CONCLUSIONS: The data demonstrate that insurance-mandated PDC is an obstacle to patient access for surgical treatment of severe obesity and has no impact on weight loss outcome or postsurgical compliance. PDC should be abandoned by the insurance industry. 相似文献
6.
In a retrospective study using univariate analysis, we identified tumor type (nonendometrioid vs endometrioid), depth of myoinvasion (MI), mode of MI (infiltrative vs cohesive), and direct anatomic invasion of the cervical wall from the isthmus as significant positive risk factors for intramyometrial lymphvascular space involvement (LVSI). On multivariate analysis, tumor grade, depth of MI, and mode of MI retained their significance. We created a grid for the relative risks of LVSI with respect to these variables individually or in combination. We suggest that our indirect estimate of the risk of LVSI can help in assessing prognosis and determining the need for adjuvant therapy whenever LVSI is important in clinical decision making, but its pathologic diagnosis is uncertain. 相似文献
7.
Summary Intracavitary application of ultrasound was first performed for diagnostic purposes in 1967; since that time, it has been
more and more widely used. As far as the gastrointestinal tract is concerned, endoscopically controlled ultrasonic probes
provide visualization of the various layers of the intestinal wall. It is therefore possible to describe lesions of the esophagus,
stomach, and the rectum with regard to their nature and depth of infiltration. Furthermore, periesophageal and perigastric
organs can be visualized. It has become evident that endosonography is particularly important for pretherapeutic staging of
tumors of the esophagus, stomach, and rectum. Here prospective comparative studies confirm the superiority of this new diagnostic
procedure when compared to the methods available to date. 相似文献
8.
Timothy M. Pawlik Kelly Olino Ana Luiza Gleisner Michael Torbenson Richard Schulick Michael A. Choti 《Journal of gastrointestinal surgery》2007,11(7):860-868
Some investigators have suggested that preoperative chemotherapy for hepatic colorectal metastases may cause hepatic injury
and increase perioperative morbidity and mortality. The objective of the current study was to examine whether treatment with
preoperative chemotherapy was associated with hepatic injury of the nontumorous liver and whether such injury, if present,
was associated with increased morbidity or mortality after hepatic resection. Two-hundred and twelve eligible patients who
underwent hepatic resection for colorectal liver metastases between January 1999 and December 2005 were identified. Data on
demographics, clinicopathologic characteristics, and preoperative chemotherapy details were collected and analyzed. The majority
of patients received preoperative chemotherapy (n = 153; 72.2%). Chemotherapy consisted of fluoropyrimidine-based regimens: 5-FU monotherapy, 31.6%; irinotecan, 25.9%; and
oxaliplatin, 14.6%. Among those patients who received chemotherapy, the type of chemotherapy regimen predicted distinct patterns
of liver injury. Oxaliplatin was associated with increased likelihood of grade 3 sinusoidal dilatation (p = 0.017). Steatosis >30% was associated with irinotecan (27.3%) compared with no chemotherapy, 5-FU monotherapy, and oxaliplatin
(all p < 0.05). Irinotecan also was associated with steatohepatitis, as two of the three patients with steatohepatitis had received
irinotecan preoperatively. Overall, the perioperative complication rate was similar between the no-chemotherapy group (30.5%)
and the chemotherapy group (35.3%) (p = 0.79). Preoperative chemotherapy was also not associated with 60-day mortality. In patients with hepatic colorectal metastases,
preoperative chemotherapy is associated with hepatic injury in about 20 to 30% of patients. Furthermore, the type of hepatic
injury after preoperative chemotherapy was regimen-specific.
Presented at the American Hepato-Pancreato-Biliary Association 2006 Annual Meeting, March 11, Miami, Florida. 相似文献
9.
Retrospective review of the preoperative biliary and gastrointestinal evaluation for gastric bypass surgery 总被引:1,自引:0,他引:1
Vincent W. Vanek M.D. C.N.S.P. F.A.C.S. Michele Catania R.N. B.S.N. Kimberly Triveri R.D. L.D. Robert W. Woodruff Jr M.D. 《Surgery for obesity and related diseases》2006,2(1):839-22
BACKGROUND: The purpose of this study was to analyze the frequency and results of preoperative biliary and gastrointestinal (GI) evaluation of patients undergoing Roux-en-Y gastric bypass (RYGB). METHODS: Retrospective review of the preoperative evaluation of 144 consecutive RYGB patients. RESULTS: Cholecystectomy had already been performed in 43 (30%) patients; 22% of those patients with an intact gallbladder had cholelithiasis. Ten patients (7%) had an upper GI x-ray (UGI), and 94 patients (65%) had an esophagogastroduodenoscopy (EGD). Abnormalities were found in 40% of the UGIs and 84% of the EGDs. A total of 96 patients (67%) were tested for Helicobacter pylori; 11% were positive. Twenty-one patients (15%) underwent preoperative colonoscopy; 48% were abnormal, but most of the abnormalities were not clinically significant. Three patients had barium enema x-ray, which was normal in all cases. CONCLUSIONS: The preoperative biliary and GI evaluation of bariatric surgery patients should include a routine ultrasound of the gallbladder. Routine preoperative EGD will detect a significant number of abnormalities that should be treated, but should rarely alter the bariatric surgical procedure or result in denial of bariatric surgery. Many abnormalities will be asymptomatic. Patients should be routinely screened for H. pylori and, if positive, treated before bariatric surgery. Lower GI evaluation should be performed selectively based on the patient's symptoms, physical findings, and guidelines for colorectal cancer and polyp screening. 相似文献
10.