全文获取类型
收费全文 | 1629篇 |
免费 | 109篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 10篇 |
儿科学 | 46篇 |
妇产科学 | 43篇 |
基础医学 | 219篇 |
口腔科学 | 39篇 |
临床医学 | 121篇 |
内科学 | 295篇 |
皮肤病学 | 23篇 |
神经病学 | 231篇 |
特种医学 | 89篇 |
外科学 | 263篇 |
综合类 | 18篇 |
预防医学 | 125篇 |
眼科学 | 40篇 |
药学 | 79篇 |
中国医学 | 6篇 |
肿瘤学 | 96篇 |
出版年
2023年 | 10篇 |
2022年 | 10篇 |
2021年 | 28篇 |
2020年 | 14篇 |
2019年 | 32篇 |
2018年 | 30篇 |
2017年 | 33篇 |
2016年 | 31篇 |
2015年 | 33篇 |
2014年 | 36篇 |
2013年 | 73篇 |
2012年 | 72篇 |
2011年 | 64篇 |
2010年 | 38篇 |
2009年 | 56篇 |
2008年 | 92篇 |
2007年 | 84篇 |
2006年 | 90篇 |
2005年 | 82篇 |
2004年 | 67篇 |
2003年 | 62篇 |
2002年 | 51篇 |
2001年 | 58篇 |
2000年 | 50篇 |
1999年 | 53篇 |
1998年 | 25篇 |
1997年 | 21篇 |
1996年 | 21篇 |
1995年 | 17篇 |
1994年 | 11篇 |
1993年 | 14篇 |
1992年 | 53篇 |
1991年 | 21篇 |
1990年 | 28篇 |
1989年 | 21篇 |
1988年 | 19篇 |
1987年 | 24篇 |
1986年 | 20篇 |
1985年 | 27篇 |
1984年 | 12篇 |
1983年 | 9篇 |
1981年 | 7篇 |
1980年 | 15篇 |
1979年 | 13篇 |
1978年 | 13篇 |
1976年 | 10篇 |
1974年 | 10篇 |
1973年 | 18篇 |
1971年 | 11篇 |
1970年 | 13篇 |
排序方式: 共有1743条查询结果,搜索用时 15 毫秒
1.
L. Matsuoka T. Shah S. Aswad S. Bunnapradist Y. Cho R. G. Mendez R. Mendez R. Selby 《American journal of transplantation》2006,6(6):1473-1478
The use of expanded criteria donors (ECD) has been proposed to help combat the discrepancy between organ availability and need. ECD kidneys are associated with delayed graft function (DGF) and worse long-term survival. The aim of this study is to evaluate the impact of pulsatile perfusion (PP) on DGF and graft survival in transplanted ECD kidneys. From January 2000 to December 2003, 4618 ECD kidney-alone transplants were reported to the United Network for Organ Sharing. PP was performed on 912 renal allografts. The prognostic factors of DGF were analyzed using multivariate logistic regression analysis. Risk factors for reduced allograft viability were greater in donors and recipients of PP kidneys. Three-year graft survival of ECD kidneys preserved with PP was similar to cold storage (CS) kidneys. The incidence of DGF in PP kidneys was significantly lower than CS kidneys (26% vs. 36%, p < 0.001). Despite having a greater number of risk factors for reduced graft viability, the ECD-PP kidneys had similar graft survival compared to ECD-CS kidneys. The use of PP, by decreasing the incidence of DGF, may possibly lead to lower overall costs and increased utilization of donor kidneys. 相似文献
2.
In 17 ambulatory patients with severe intermittent dysphagia an endoscopic electrosurgical radial incision of a Schatzki ring was made with a modified straight retractable sphincterotome. The incision was successfully accomplished with immediate relief of dysphagia in all patients. Fourteen patients remain asymptomatic with a mean follow-up of 46 months after the first treatment. Three patients required a second incision and they have been asymptomatic for more than 24 months. There was one mild bleeding episode. Endoscopic electrosurgical incision of the Schatzki ring is an effective therapeutic modality in selected patients. 相似文献
3.
T-cell dysregulation in patients with hyperprolactinemia: effect of bromocriptine treatment 总被引:1,自引:0,他引:1
A Vidaller L Llorente F Larrea J P Mendez J Alcocer-Varela D Alarcon-Segovia 《Clinical immunology and immunopathology》1986,38(3):337-343
We studied four patients with tumoral hyperprolactinemia and normal ovarian function before and after prolactine levels had become normal with treatment with bromocriptine (BrC), a dopamine agonist that inhibits prolactin release. Their proliferative responses to concanavalin A, pokeweed mitogen, and, to a lesser extent, phytohemagglutinin, their spontaneous and concanavalin A-induced suppression, and their production of interleukin 2 were found to be decreased and to correct partially or completely after bromocriptine treatment. The T-cell response to interleukin 2 was low in two patients in whom it increased after BrC treatment. These findings give insight on the immunomodulatory role of prolactin in vivo. 相似文献
4.
5.
C Casanova C G Cote J M Marin J P de Torres A Aguirre-Jaime R Mendez L Dordelly B R Celli 《The European respiratory journal》2007,29(3):535-540
The 6-min walking distance (6MWD) test is used in clinical practice and research into patients with chronic obstructive pulmonary disease (COPD). However, little is known about natural long-term change in this parameter. The 6MWD was measured at baseline and then annually for 5 yrs in 294 patients with COPD and its annual rate of decline was determined. Forced expiratory volume in one second (FEV1) was also measured and the relationship between changes in both markers was explored. At baseline, the median 6MWD was 380 m (range 160-600 m). It declined by 19% (16 m.yr(-1)) over the 5 yrs compared with baseline in patients with American Thoracic Society/European Respiratory Society stage III COPD (FEV1 30-50% predicted) and by 26% (15 m.yr(-1)) in patients with stage IV COPD (FEV1 <30% pred). Over the 5-yr follow-up, the proportion of patients with a minimal clinically significant decline of 54 m increased with the severity of the disease. It was 24% in stage II, 45% in stage III, and 63% in stage IV disease. In contrast, the rate of decline of FEV1 was greater in patients with milder airflow obstruction and lesser in patients with lower absolute FEV1 values. In conclusion, the 6-min walking distance test provides increasingly useful information as the severity of chronic obstructive pulmonary disease increases. 相似文献
6.
Prospective study of antigenemia,plasma viremia and lymphocytic viremia in HIV-infected hemophiliacs
S. Melón Garcia M. de Oña Navarro C. Rodriguez Pinto M. Fernández Urgellés A. Martinez Gutierrez P. de la Iglesia F. J. Mendez García 《European journal of clinical microbiology & infectious diseases》1995,14(5):400-405
A total of 186 blood samples from 24 HIV-1 seropositive hemophiliac patients, monitored every four months for 29 months, were investigated for the presence of viral antigen in plasma. In addition, peripheral blood mononuclear cells (PBMC) were cultured for HIV-1, using normal PBMC as a target for replication. Antigenemia was detected in 51 % of the patients and from PBMC in 87.5 % of the patients. The incidence of HIV isolation in asymptomatic patients (42.8 %) was similar to that found in symptomatic patients (51.4 %). Patients with opportunistic infections had a higher incidence of lymphocytic viremia (p<0.05). Plasma viremia was closely associated (p<0.05) with low CD4+ counts and infection progression. The persistence of antigenemia was also a marker of a poor clinical course. In treated patients, plasma viremia was the marker that better correlated with the clinical course, and it did not appear during the first nine months of therapy. Zidovudine doses of >500 mg/day significantly lowered the appearance of antigenemia and lymphocytic viremia (p<0.05). 相似文献
7.
J. G. Gross W. R. Freeman M. H. Goldbaum T. L. Mendez 《The British journal of ophthalmology》1989,73(6):435-439
Many vitreoretinal procedures are performed in offices and hospitals where cost control is important. We describe three useful devices and techniques that facilitate these procedures at minimal expense and often greater convenience. These include an accurate method for localising the pars plana without the use of callipers, an inexpensive, reliable, pressure regulated air pump for fluid-air exchange, and an easy method for intraocular injection of silicone oil through 20 gauge instrumentation without the need for expensive pumps. These procedures and techniques should prove to be useful in the treatment of vitreoretinal disease. 相似文献
8.
9.
S Varela J Mendez C González de la Cuesta I Iglesias C González M Menéndez 《Journal of investigational allergology & clinical immunology》2003,13(2):124-130
A retrospective study was performed to describe the features of the pollinosis caused by Betula in the area of Ourense, Spain. The pollen count was carried out with a Lanzoni volumetric Hirts spore trap (1993-2000). The Betula pollen represented 5% over the annual total (annual mean quantity: 965 grains). It was present in the air from March to mid-May. The highest peaks took place in April (maximum values mean: 131 grains/m3). The medical records of 222 patients (mean age 25.66 years) diagnosed with pollinosis (1998-2000), who lived at less than 30 km. from the spore trap, were reviewed. In all of them, the skin-prick test (SPT) was carried out with pollen allergens. The percentages of positive SPT were: Lolium perenne, 91.89% (16.6% monosensitized); Plantago lanceolata, 71.17% (1.26% monosensitized); Betula alba, 41.89% (10.75% monosensitized); Platanus hybrida, 34.95%; Olea europea, 10.36%; and Parietaria judaica, 6.3%. The mean age of Betula monosensitized patients was 44.7 years. The majority of them had symptoms in March-April, 40% had asthma symptoms, 80% had lived in Central Europe, and 30% of them presented an oral allergy syndrome to fruits. There were 41.93% of the patients with positive SPT to Betula pollen who had asthma symptoms, in comparison with 23.25% of the patients with negative SPT to Betula (p = 0.0034). There were 20.28% of the patients with positive SPT to Betula pollen, who had lived in Central Europe, in comparison with 4.27% of the patients with negative SPT to Betula, p: 0.00049. The relative risk of sensitization was 2.05. CONCLUSIONS: Betula pollen was the second cause of clinical pollinosis in our patients, after grass, being responsible of the symptoms in the early spring, in a small number of the patients in their forties. The presence of asthma was higher in Betula sensitized patients, and the residence in Central Europe was a sensitization risk factor. 相似文献
10.
R. L. Cabrini A. E. Schwint A. Mendez F. Femopase H. Lanfranchi M. E. Itoiz 《Journal of oral pathology & medicine》1992,21(6):275-279
A morphometric study of nucleolar organizer regions (NOR) was performed to analyze their distribution, volume, number and shape in the different strata of human normal oral mucosa epithelium and papilloma and in squamous cell carcinoma employing microphotographs of silver-stained paraffin sections. The different NOR-related parameters evidenced significant differences between normal mucosa, papilloma and squamous cell carcinoma. The functional polarity of normal mucosa epithelium and of papilloma is also evidenced in terms of NOR-related parameters. The discriminative value of certain NOR parameters was demonstrated. 相似文献