全文获取类型
收费全文 | 13699篇 |
免费 | 1003篇 |
国内免费 | 37篇 |
专业分类
耳鼻咽喉 | 90篇 |
儿科学 | 498篇 |
妇产科学 | 355篇 |
基础医学 | 1856篇 |
口腔科学 | 174篇 |
临床医学 | 1714篇 |
内科学 | 2470篇 |
皮肤病学 | 270篇 |
神经病学 | 1328篇 |
特种医学 | 292篇 |
外科学 | 1689篇 |
综合类 | 202篇 |
一般理论 | 26篇 |
预防医学 | 1543篇 |
眼科学 | 165篇 |
药学 | 936篇 |
中国医学 | 32篇 |
肿瘤学 | 1099篇 |
出版年
2023年 | 55篇 |
2022年 | 97篇 |
2021年 | 239篇 |
2020年 | 188篇 |
2019年 | 283篇 |
2018年 | 346篇 |
2017年 | 204篇 |
2016年 | 258篇 |
2015年 | 264篇 |
2014年 | 415篇 |
2013年 | 637篇 |
2012年 | 966篇 |
2011年 | 882篇 |
2010年 | 518篇 |
2009年 | 523篇 |
2008年 | 863篇 |
2007年 | 951篇 |
2006年 | 830篇 |
2005年 | 909篇 |
2004年 | 822篇 |
2003年 | 813篇 |
2002年 | 727篇 |
2001年 | 144篇 |
2000年 | 128篇 |
1999年 | 148篇 |
1998年 | 140篇 |
1997年 | 147篇 |
1996年 | 131篇 |
1995年 | 119篇 |
1994年 | 86篇 |
1993年 | 98篇 |
1992年 | 111篇 |
1991年 | 99篇 |
1990年 | 81篇 |
1989年 | 94篇 |
1988年 | 78篇 |
1987年 | 76篇 |
1986年 | 68篇 |
1985年 | 99篇 |
1984年 | 68篇 |
1983年 | 73篇 |
1982年 | 86篇 |
1981年 | 78篇 |
1980年 | 66篇 |
1979年 | 48篇 |
1978年 | 76篇 |
1977年 | 62篇 |
1976年 | 37篇 |
1975年 | 41篇 |
1973年 | 37篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
901.
902.
Savarirayan R Boyle RJ Masel J Rogers JG Sheffield LJ 《American journal of medical genetics. Part A》2004,(2):148-157
We report the longterm clinical and radiological progression in three unrelated patients with the tibia-metacarpal form of chondrodysplasia punctata (CDP-TM). The patients were followed for 37, 25, and 32 years, respectively. At follow-up intellectual function was normal, and physical function was well preserved. There was also marked resolution of several significant early radiographic features. The patients attained adult heights of 152, 138, and 148 cm. Two patients had chronic serous otitis media requiring tympanostomy tubes during childhood. One patient suffered persisting back pain related to spinal stenosis and required lumbar laminectomy at the age of 26 years. One patient had hip dysplasia requiring orthopedic surgical intervention. All patients had recurrent patella dislocation. Sterol and very long chain fatty acid profiles, FISH analysis for SHOX gene deletions, blood lymphocyte karyotype, and phytanic acid levels were normal in those tested, and no mutations in arylsulfatase D and E genes were detected. These data suggest that the longterm clinical and functional prognosis in this condition appears to be better than that expected based on initial clinical and radiological findings. 相似文献
903.
904.
Yoo GH Nguyen NX Du W Schwartz AG Land S Lin HS Kewson D Murphy LL Cilluffo D Ensley JF Tainsky MA 《The Laryngoscope》2004,114(9):1619-1624
OBJECTIVE: To determine the genetic differences between African Americans (AA) and Non-African Americans (NAA) with head and neck squamous cell carcinoma (HNSCC). METHODS: DNA was obtained from tumor tissues and peripheral blood from 18 AA and 19 NAA patients with HNSCC. Microsatellite analysis using a fluorescent technique was performed on chromosomal arms 1p, 3p, 4q, 9p, 13q, and 17p. Statistical analyses were performed on the molecular and clinical outcome data. RESULTS: Based on the Surveillance, Epidemiologic, and End Result (SEER) data from southeast Michigan, the incidence rate of HNSCC in AA has been higher than for NAA, and the overall 5-year relative survival rate is lower for AA than NAA (36.2% vs. 47.6%). In this study, we found that the rate of loss of heterozygosity of chromosomal arms 1p, 3p, 4q, 9p, 13q, and 17p ranged from 68.8% to 83.3% for HNSCC in AA and from 66.7% to 90.0% in NAA. The difference in the rates of microsatellite alterations in chromosomal arms 3p, 4q, and 9p between AA and NAA were between 12.5% and 20% and were not statistically significant. CONCLUSION: The incidence and clinical outcomes for AA with HNSCC are different from that of NAA in southeast Michigan. In our group of patients with HNSCC, differences in rates of microsatellite alterations and survival were found between AA and NAA; however, these differences were not statistically significant. We conclude that genetic difference, as determined by the rates of microsatellite alterations, is not predictive of outcome difference between AA and NAA HNSCC patients. 相似文献
905.
Mills N Anderson BJ Barber C White J Mahadevan M Salkeld L Douglas G Brown C 《International journal of pediatric otorhinolaryngology》2004,68(11):1367-1373
OBJECTIVE: There is a controversy about day stay pediatric tonsillectomy in the UK and Australia. New Zealand has a similar health structure and we wished to compare day stay tonsillectomy from our hospital with those reported from other centers. METHODS: We performed a prospective audit of day stay tonsillectomy to determine conversion to hospital admission rate and the incidence of postoperative hemorrhage. RESULTS: There were 4850 paediatric tonsillectomies performed with 80% of them as day stay procedures over a 9-year study period (1993-2002) in a university-affiliated tertiary children's hospital. The primary postoperative hemorrhage rate (within 24h of surgery) was 0.9% (CI 0.68-1.22%) and 83% occurred within the mandatory 4h postoperative observation period. Primary hemorrhage requiring re-operation to achieve hemostasis occurred in 18 children (0.37%, CI 0.2-0.54%). No child with a primary hemorrhage who presented after discharge following day stay surgery required re-operation or blood transfusion. Day stay surgery was planned in 4041 children and 4.7% (CI 4.1-5.4%) required conversion to hospital admission. Postoperative vomiting was the most common indication for conversion (2.65%, CI 2.2-3.1%), while hemorrhage contributed only 0.95% (CI 0.64-1.24%). CONCLUSIONS: This study was performed in a health system similar to that of Australia and the UK. Complication and conversion rates are similar to those reported in North American centers. Pediatric day stay tonsillectomy is a safe procedure when performed with strict preoperative criteria, trained day stay unit (DSU) staff, and with in-patient facilities on site. 相似文献
906.
907.
Five new antipsychotic drugs introduced in the United States in the last decade offer physicians the ability to treat patients with schizophrenia and bipolar mania without the adverse effects of the first-generation antipsychotics. In this article, the authors discuss the advantages and side effects of these agents and present a guide to help physicians choose the optimal drug in the most favorable formulation for each patient. 相似文献
908.
909.
Inhibitory activities of colicins against Escherichia coli strains responsible for postweaning diarrhea and edema disease in swine 下载免费PDF全文
Stahl CH Callaway TR Lincoln LM Lonergan SM Genovese KJ 《Antimicrobial agents and chemotherapy》2004,48(8):3119-3121
The efficacies of colicins E1 and N against Escherichia coli strains responsible for postweaning diarrhea and edema disease, two of the most prevalent disease problems for pigs in the United States, were determined in vitro. These proteins may provide an environmentally sound means for the prevention of these infections in swine. 相似文献
910.
Regional variations in breast cancer among california teachers 总被引:2,自引:0,他引:2
Reynolds P Hurley S Goldberg DE Anton-Culver H Bernstein L Deapen D Horn-Ross PL Peel D Pinder R Ross RK West D Wright WE Ziogas A 《Epidemiology (Cambridge, Mass.)》2004,15(6):746-754
BACKGROUND: Observed regional differences in breast cancer incidence could provide valuable clues to the etiology of this disease. The pattern of historically higher breast cancer rates among residents of California's San Francisco Bay and Southern Coastal areas is evident in the disease experience among members of the California Teachers Study. This large cohort study has followed female professional school employees for cancer incidence since 1995 and has collected extensive information on breast cancer risk factors. METHODS: Between 1996 and 1999, invasive breast cancer was diagnosed in 1562 of the 115,611 cohort members who could be geocoded to a California address in 1995 and who had no previous breast cancer diagnosis. Adjusted hazard rate ratios (HRs) were estimated through multivariate Cox proportional hazards modeling. RESULTS: Rates were higher for cohort members in the San Francisco Bay area (HR = 1.22; 95% confidence interval = 1.06-1.40) and Southern Coastal area (1.16; 1.04-1.30) compared with those in the rest of California. The distributions of variables representing socioeconomic status, urbanization, and personal risk factors were consistent with higher risks for cohort members residing in the San Francisco Bay and Southern Coastal areas. Adjustment for these factors, however, did not explain regional differences in incidence, resulting in HRs that remained elevated for these 2 areas. CONCLUSION: Regional differences in breast cancer incidence in this large, well-defined cohort are not easily explained by known risk factors. 相似文献