全文获取类型
收费全文 | 6251篇 |
免费 | 385篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 51篇 |
儿科学 | 463篇 |
妇产科学 | 66篇 |
基础医学 | 800篇 |
口腔科学 | 86篇 |
临床医学 | 450篇 |
内科学 | 1111篇 |
皮肤病学 | 134篇 |
神经病学 | 312篇 |
特种医学 | 203篇 |
外科学 | 771篇 |
综合类 | 181篇 |
一般理论 | 1篇 |
预防医学 | 449篇 |
眼科学 | 205篇 |
药学 | 718篇 |
中国医学 | 35篇 |
肿瘤学 | 605篇 |
出版年
2023年 | 37篇 |
2022年 | 69篇 |
2021年 | 164篇 |
2020年 | 94篇 |
2019年 | 93篇 |
2018年 | 150篇 |
2017年 | 112篇 |
2016年 | 154篇 |
2015年 | 152篇 |
2014年 | 216篇 |
2013年 | 270篇 |
2012年 | 392篇 |
2011年 | 429篇 |
2010年 | 256篇 |
2009年 | 188篇 |
2008年 | 327篇 |
2007年 | 308篇 |
2006年 | 272篇 |
2005年 | 252篇 |
2004年 | 224篇 |
2003年 | 207篇 |
2002年 | 155篇 |
2001年 | 181篇 |
2000年 | 144篇 |
1999年 | 144篇 |
1998年 | 50篇 |
1997年 | 45篇 |
1996年 | 36篇 |
1995年 | 39篇 |
1992年 | 101篇 |
1991年 | 73篇 |
1990年 | 84篇 |
1989年 | 91篇 |
1988年 | 67篇 |
1987年 | 68篇 |
1986年 | 67篇 |
1985年 | 84篇 |
1984年 | 64篇 |
1983年 | 56篇 |
1980年 | 33篇 |
1979年 | 70篇 |
1978年 | 39篇 |
1977年 | 38篇 |
1976年 | 48篇 |
1975年 | 66篇 |
1974年 | 38篇 |
1973年 | 60篇 |
1971年 | 41篇 |
1970年 | 32篇 |
1969年 | 39篇 |
排序方式: 共有6641条查询结果,搜索用时 15 毫秒
31.
Rohit R. Badia Solomon Woldu Hiten D. Patel Nirmish Singla Arnav Srivastava Joseph G. Cheaib Phillip M. Pierorazio Aditya Bagrodia 《Urologic oncology》2021,39(2):136.e19-136.e25
BackgroundThe American Joint Committee on Cancer 8th edition staging guidelines for testicular cancer established a 3 cm cutoff to subclassify stage T1 seminomas (<3 cm = pT1a and ≥3 cm = pT1b). The efficacy of this cutoff in predicting metastatic disease and impact on treatment patterns have not been studied.MethodsWe retrospectively reviewed patients with pT1 testicular seminoma in the National Cancer Database from 2004 to 2016. Receiver operating curves were used to determine the efficacy of the 3 cm tumor cutoff in identifying metastatic disease, and multivariable regression was used to compute the effect of tumor size on the rate of adjuvant therapy among Stage I patients.ResultsA total of 10,134 patients with pT1 seminoma were evaluated. The current size cutoff of 3 cm for subclassification did not exhibit high discrimination in identifying metastatic disease (area under receiver operating curve: 0.546). Surveillance has grown as the preferred treatment after orchiectomy ?32.1% in 2004 to 81.2% in 2015. However, the rate of adjuvant therapy for pT1, Stage I seminomas associated positively with tumor size even with adjustment for year of diagnosis. For tumors above 3 cm, the odds ratio stabilized around 1.9. By using the 3 cm cutoff to guide adjuvant therapy, up to 85% of T1b patients may be overtreated.ConclusionThe 3 cm cutoff for subclassification of Stage I seminoma does not predict metastatic recurrence but is associated with increased receipt of adjuvant therapy. A 3 cm cutoff and the pT1a/b classification may therefore contribute to overtreatment in many young patients with a long life expectancy for whom minimizing adverse effects should be prioritized. 相似文献
32.
33.
Wen MC Wei CH Hu ZQ Srivastava K Ko J Xi ST Mu DZ Du JB Li GH Wallenstein S Sampson H Kattan M Li XM 《The Journal of allergy and clinical immunology》2005,116(3):517-524
BACKGROUND: Chinese herbal medicine has a long history of human use. A novel herbal formula, anti-asthma herbal medicine intervention (ASHMI), has been shown to be an effective therapy in a murine model of allergic asthma. OBJECTIVE: This study was undertaken to compare the efficacy, safety, and immunomodulatory effects of ASHMI treatment in patients with moderate-severe, persistent asthma with prednisone therapy. METHODS: In a double-blind trial, 91 subjects underwent randomization. Forty-five subjects received oral ASHMI capsules and prednisone placebo tablets (ASHMI group) and 46 subjects received oral prednisone tablets and ASHMI placebo capsules (prednisone group) for 4 weeks. Spirometry measurements; symptom scores; side effects; and serum cortisol, cytokine, and IgE levels were evaluated before and after treatment. RESULTS: Posttreatment lung function was significantly improved in both groups as shown by increased FEV(1) and peak expiratory flow findings (P<.001). The improvement was slightly but significantly greater in the prednisone group (P<.05). Clinical symptom scores, use of beta(2)-bronchodilators, and serum IgE levels were reduced significantly, and to a similar degree in both groups (P<.001). T(H)2 cytokine levels were significantly reduced in both treated groups (P<.001) and were lower in the prednisone-treated group (P<.05). Serum IFN-gamma and cortisol levels were significantly decreased in the prednisone group (P<.001) but significantly increased in the ASHMI group (P<.001). No severe side effects were observed in either group. CONCLUSION: Anti-asthma herbal medicine intervention appears to be a safe and effective alternative medicine for treating asthma. In contrast with prednisone, ASHMI had no adverse effect on adrenal function and had a beneficial effect on T(H)1 and T(H)2 balance. 相似文献
34.
Mutational analysis of the PTEN/MMAC1 gene in primary oesophageal squamous cell carcinomas. 总被引:4,自引:0,他引:4
AIM: To investigate whether PTEN/MMAC1 mutations play a role in the carcinogenesis of oesophageal squamous cell carcinoma. METHODS: A panel of 33 primary oesophageal squamous cell carcinoma tumour samples and 20 corresponding morphologically normal tissues was examined for mutations in all nine exons of the PTEN/MMAC1 gene by means of polymerase chain reaction single strand conformational polymorphism analysis (PCR-SSCP) and direct DNA sequencing methods. RESULTS: Only one of 33 oesophageal squamous cell carcinomas showed an aberrant SSCP band. Further sequencing analysis of this sample revealed an 802 -29 T-->C substitution in intron 7. PTEN/MMAC1 mutations were not found in the mutational "hot spot" in exon 5, even after direct sequencing of six oesophageal squamous cell carcinoma samples and three normal tissues. However, a deletion of one nucleotide T at position 492 +8 in intron 5 was seen in all samples. CONCLUSION: These results suggest that PTEN/MMAC1 mutations do not play a major role in the carcinogenesis of oesophageal squamous cell carcinoma. 相似文献
35.
Myocardial infarction complicating gastrointestinal hemorrhage 总被引:5,自引:0,他引:5
Emenike E Srivastava S Amoateng-Adjepong Y al-Kharrat T Zarich S Manthous CA 《Mayo Clinic proceedings. Mayo Clinic》1999,74(3):235-241
OBJECTIVE: To determine the frequency of and risk factors for myocardial infarction (MI) in patients admitted to an intensive-care unit (ICU) with gastrointestinal (GI) hemorrhage and to ascertain the effects on mortality and lengths of stay. MATERIAL AND METHODS: Demographic, laboratory, and outcome data were determined for all patients admitted to a medical ICU with GI hemorrhage between April 1996 and January 1997. Serial creatine kinase with isoenzyme levels and electrocardiograms were interpreted blindly by a senior cardiologist. RESULTS: For 83 consecutive admissions to the ICU because of GI hemorrhage, the patients' mean (+/- standard error) age was 65.0 +/- 1.7 years and APACHE II (acute physiology and chronic health evaluation) score was 15.7 +/- 0.8. In-hospital death occurred in 16 patients (19%). Patients who did not survive had a lower admission systolic blood pressure (99.2 +/- 4.5 versus 115.0 +/- 4.0 mm Hg; P = 0.01) than did those who survived. Eleven of 83 patients (13%) fulfilled both enzymatic and electrocardiographic criteria for MI. Ten patients (12%) had electrocardiographic evidence of myocardial ischemia but did not meet criteria for MI. Patients with MI were older (74.4 +/- 4.0 versus 61.7 +/- 2.0 years; P < 0.05), had a higher acuity of illness (APACHE II score, 21.6 +/- 3.0 versus 14.6 +/- 0.7; P < 0.05), and had more coronary risk factors (2.3 +/- 0.3 versus 1.4 +/- 0.1; P < 0.05) in comparison with those without MI or ischemia. Patients with MI also had longer ICU (8.6 +/- 2.4 versus 3.3 +/- 0.4 days; P < 0.05) and hospital (16.3 +/- 3.4 versus 9.1 +/- 0.8 days; P < 0.05) lengths of stay. Patients older than 65 years had a threefold increased risk (risk ratio, 4.0; 95% confidence interval, 0.9 to 17.4) and those with two or more risk factors for coronary artery disease had a ninefold increased risk of MI (risk ratio, 10.2; 95% confidence interval, 1.4 to 76.1) in comparison with those who were younger or who had fewer coronary risk factors, respectively. MI complicating GI hemorrhage did not significantly affect the risk of in-hospital mortality (risk ratio, 1.5; 95% confidence interval, 0.5 to 4.4). CONCLUSION: MI occurs frequently in patients with GI hemorrhage admitted to an ICU. Age more than 65 years and two or more risk factors for coronary artery disease identify patients who are at greatest risk for occurrence of MI, which is associated with longer ICU and hospital stays. 相似文献
36.
37.
Prognostic impact of ANX7-GTPase in metastatic and HER2-negative breast cancer patients. 总被引:4,自引:0,他引:4
Meera Srivastava Lukas Bubendorf Mark Raffeld Christoph Bucher Jochen Torhorst Guido Sauter Cara Olsen Olli P Kallioniemi Ofer Eidelman Harvey B Pollard 《Clinical cancer research》2004,10(7):2344-2350
PURPOSE: ANX7-GTPase located on chromosome 10q21 is significantly altered and associated with hormone-refractory metastatic prostate cancers. Therefore, we investigated whether levels of ANX7 correlate with breast cancer progression and survival EXPERIMENTAL DESIGN: A diagnostic tumor tissue microarray containing 525 human breast tissue specimens at different stages of the disease was assayed for ANX7 using immunocytochemical methods with ANX7 monoclonal antibody. A separate prognostic tumor tissue microarray containing 553 human breast tissue specimens annotated with clinicopathological parameters was assayed for ANX7, HER2, estrogen receptor, progesterone receptor, and p53 protein. RESULTS: We report here for the first time that the expression of ANX7-GTPase is significantly enhanced and associated with the presence of metastatic disease (P < 0.0001) in the 525 human breast tissue specimens analyzed. Furthermore, using a separate 553 case retrospective prognostic tumor tissue microarray, we found that increased ANX7 expression is also significantly associated with poor overall patient survival (P < 0.014). This is particularly true when restricted to patients in whom the BRE clinical grade is 2 (P < 0.001) or for whom there is a lack of HER2 expression (P < 0.002). Finally, Cox regression analysis shows that as the expression of ANX7 rises, the probability of survival decreases by more than 10-fold for those patients with HER2-negative tumors. These latter patients represented 66% of the population affected with breast cancer in this study. CONCLUSIONS: High levels of ANX7 in tumor correlate strongly with poor survival of HER2-negative patients and the most aggressive forms of breast cancer. This is the first study to demonstrate that ANX7 antibody has the potential for development into an in vivo diagnostic and therapeutic tool. This simple and reliable immunohistochemical assay may therefore become an important biomarker for metastatic breast cancer diagnosis and management of HER2-negative breast tumor patients. 相似文献
38.
The concentration of chlorinated pesticides and heavy metals (lead and cadmium) was measured using gas liquid chromatography and the graphite tube atomizer of atomic absorption spectrophotometer, respectively, in semen samples collected from men in the normal human population. Significant concentrations of lead and cadmium were detected. Significant amounts of hexachlorocyclohexane (HCH) and its isomers alpha, beta, gamma and delta, the dichlorodiphenyl trichloroethane (DDT) metabolite 1,1,1-trichloro-2,2-bis (p chlorophenyl ethane) (pp'-DDE) and low values of 1,1,2-dichloro-2, 2-bis(p chlorophenyl ethane) (pp'-DDD) aldrin or endosulfan were detected. The presence of these xenobiotics in human semen might be related to the extensive use of pesticides, emission of exhaust from motor vehicles, consumption of tobacco and industrial operations. 相似文献
39.
40.