全文获取类型
收费全文 | 3441篇 |
免费 | 279篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 26篇 |
儿科学 | 114篇 |
妇产科学 | 83篇 |
基础医学 | 469篇 |
口腔科学 | 22篇 |
临床医学 | 514篇 |
内科学 | 561篇 |
皮肤病学 | 55篇 |
神经病学 | 342篇 |
特种医学 | 102篇 |
外科学 | 453篇 |
综合类 | 86篇 |
一般理论 | 7篇 |
预防医学 | 322篇 |
眼科学 | 28篇 |
药学 | 195篇 |
1篇 | |
中国医学 | 2篇 |
肿瘤学 | 351篇 |
出版年
2023年 | 19篇 |
2022年 | 20篇 |
2021年 | 53篇 |
2020年 | 32篇 |
2019年 | 61篇 |
2018年 | 58篇 |
2017年 | 43篇 |
2016年 | 49篇 |
2015年 | 69篇 |
2014年 | 74篇 |
2013年 | 118篇 |
2012年 | 163篇 |
2011年 | 174篇 |
2010年 | 91篇 |
2009年 | 97篇 |
2008年 | 184篇 |
2007年 | 171篇 |
2006年 | 185篇 |
2005年 | 173篇 |
2004年 | 156篇 |
2003年 | 127篇 |
2002年 | 113篇 |
2001年 | 117篇 |
2000年 | 141篇 |
1999年 | 105篇 |
1998年 | 46篇 |
1997年 | 43篇 |
1996年 | 35篇 |
1995年 | 29篇 |
1994年 | 34篇 |
1993年 | 27篇 |
1992年 | 81篇 |
1991年 | 78篇 |
1990年 | 49篇 |
1989年 | 69篇 |
1988年 | 55篇 |
1987年 | 47篇 |
1986年 | 41篇 |
1985年 | 44篇 |
1984年 | 43篇 |
1983年 | 32篇 |
1982年 | 35篇 |
1981年 | 21篇 |
1980年 | 21篇 |
1979年 | 20篇 |
1978年 | 25篇 |
1975年 | 21篇 |
1974年 | 24篇 |
1973年 | 28篇 |
1972年 | 18篇 |
排序方式: 共有3733条查询结果,搜索用时 15 毫秒
1.
2.
Several psychophysiological abnormalities associated with schizophrenia have been proposed as genetic trait markers of vulnerability to the disorder. Smooth pursuit eye tracking dysfunction and abnormal long latency event-related potentials are the most promising candidates. Both are independent of the effects of psychotropic medication or mental state at the time of testing, and twin studies demonstrate that each has a high level of heritability. Having recorded smooth pursuit eye tracking and event-related potentials in 20 high-density schizophrenic families, we find abnormalities in one or both measures in most of the families studied. The abnormalities, when present, occur in the family members with schizophrenia and other forms of functional psychosis, and they have a bimodal distribution with approximately half the nonschizophrenic relatives also showing eye tracking dysfunction and/or abnormal event-related potentials. Some of these relatives had psychiatric symptoms; others were normal. Our results suggest that psychophysiological examination can help to clarify the boundaries of schizophrenia spectrum disorder. By helping to decide the phenotypic status of nonschizophrenic family members, this should increase the power of DNA linkage studies. 相似文献
3.
Dilatation and curettage (D+C) is the most common operation performed in Britain. The liberal use of D+C has been criticised.
The objective of this study was to evaluate the use of outpatient endometrial pipelle biopsy and determine its safety in terms
of detecting abnormalities. Complications and financial costs were also evaluated. Data were reviewed from an active gynaecological
unit from February 1993 to January 1995. A total of 303 D+Cs and 104 endometrial pipelle biopsies were performed in this period.
Nine malignancies were detected by D+C and 1 by pipelle biopsy. A total of 24 and 3 benign abnormalities were detected by
each method respectively. There was a higher complication rate in the D+C group but the failure rate was higher in the endometrial
pipelle biopsy group. The monetary savings over this period is estimated at £20,307. There were no missed malignancies to
our knowledge over the 8 yr period since endometrial pipelle biopsy was introduced to the hospital. 相似文献
4.
The pedicle patch urethroplasty provides an alternative single-stage vascularised graft procedure for the repair of moderately severe hypospadias. Over a 7-year period, 38 primary hypospadias repairs were performed employing this technique. The fistula rate was 18% in the 34 patients reviewed, but there were few other significant complications. The operation is recommended when the urethral plate can be preserved and the penis straightened in boys who are unsuitable for a meatal-based flap. 相似文献
5.
Edward Black Jason Niamat Srikanth Boddu Antonio Martin-Ucar John P Duffy William Ellis Morgan Francis David Beggs 《European journal of cardio-thoracic surgery》2006,29(2):244-247
OBJECTIVE: There are limited and conflicting data available concerning the incidence of inadvertent splenectomy and its impact on the outcome in patients who have undergone oesophagectomy. The aim of this study is to identify the factors associated with a likelihood of inadvertent splenectomy and its influence on early and long-term outcome in patients having oesophagectomy for oesophageal carcinoma. METHODS: A consecutive series of 738 oesophagectomies performed between 1991 and 2004 was analysed. In our practice, the spleen was removed only if damaged intraoperatively. Routine chemo- and immunoprophylaxis would subsequently be used. Multivariate analysis with logistic and Cox models determined significant variables. RESULTS: Of the 738 oesophagectomies, 48 (6.5%) had splenectomy. Neoadjuvant chemotherapy was administered to a minority of patients; none subsequently had splenectomy. There were significant differences between types of operation (Ivor-Lewis 18 (9.0%), left thoracolaparotomy 14 (9.9%) and left thoracophrenotomy 15 (3.9%), p=0.01). Splenectomy was more common with advanced N stage disease (OR=0.44 [0.20-0.95]; p=0.04). Splenectomy resulted in more blood transfusions (median, 2 units vs 0 units; p=0.03) more anastomotic leaks (7 [14.6%] vs 42 [6.1%]; p=0.02) but not an increase in pulmonary complications (p=0.64) or in-hospital mortality (1 [4.6%] vs 37 [5.4%]; p=0.30). Splenectomy did not significantly affect median survival (551 [332-770] days vs 627 [554-700] days; p=0.63). CONCLUSION: Although inadvertent splenectomy increased the morbidity of oesophagectomy, it did not impair survival. Type of operation and advanced N stage are important risks for splenectomy. Though best avoided, most of the consequences of splenectomy can be managed. An unexpected relationship between splenectomy and anastomotic leaks needs further investigation. 相似文献
6.
7.
8.
9.
Ultrasound and more recently colour Doppler ultrasound has been successfully used in the diagnosis of lower limb venous occlusive disease. Colour Doppler ultrasound has shown promise in the diagnosis of calf vein thrombosis but to date there has been no prospective trial to specifically evaluate its potential. In view of this, we carried out a prospective trial of 50 patients comparing the accuracy of colour Doppler ultrasound with venography in the diagnosis of deep venous thrombosis both above and below knee but in particular with respect to the detection of calf vein clot. Of the 50 patients studied, 10 had only one imaging modality performed as there were eight venographic failures and two ultrasonic failures. Comparison was only thus possible in 40 cases. As in previous studies, colour Doppler ultrasound was shown to be accurate in the diagnosis of thrombosis within the femoro-popliteal veins and had a sensitivity and specificity of 100% respectively. With respect to calf vein lesions, there was one false negative scan using the ultrasonic technique giving a sensitivity of 95%, specificity of 100% and accuracy of 97.5%. We feel colour Doppler ultrasound can and should be used as a first line alternative to venography and can be employed for the exclusion of both above and below knee deep venous thrombosis. Venography should now be reserved for those patients who are unsuitable for ultrasound examination or who have an equivocal ultrasound scan. 相似文献
10.
Development of leukemia after doxorubicin and cisplatin treatment for ovarian cancer 总被引:1,自引:0,他引:1
Alkylating agents have been the major group of chemotherapeutic agents associated with an increased incidence of secondary leukemias. In ovarian cancer alkylating agents have resulted in a lesser, although still increased, risk of secondary malignancies. This paper reports two cases of ovarian cancer treated with cisplatin and doxorubicin (Adriamycin, Adria Laboratories, Columbus, OH), and the subsequent development of an acute nonlymphocytic leukemia and a preleukemia syndrome. This regimen does not contain alkylating agents, and has not been associated with leukemia in patients with ovarian cancer. In these two cases, abnormalities of chromosomes 5, 7, 11, and 17 are reported which have been shown to occur in therapy-related leukemia. 相似文献