全文获取类型
收费全文 | 567篇 |
免费 | 42篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 7篇 |
妇产科学 | 9篇 |
基础医学 | 77篇 |
口腔科学 | 68篇 |
临床医学 | 48篇 |
内科学 | 132篇 |
皮肤病学 | 21篇 |
神经病学 | 34篇 |
特种医学 | 22篇 |
外科学 | 38篇 |
综合类 | 2篇 |
预防医学 | 60篇 |
眼科学 | 5篇 |
药学 | 56篇 |
中国医学 | 6篇 |
肿瘤学 | 25篇 |
出版年
2023年 | 18篇 |
2022年 | 20篇 |
2021年 | 39篇 |
2020年 | 27篇 |
2019年 | 26篇 |
2018年 | 35篇 |
2017年 | 12篇 |
2016年 | 20篇 |
2015年 | 22篇 |
2014年 | 24篇 |
2013年 | 36篇 |
2012年 | 42篇 |
2011年 | 53篇 |
2010年 | 33篇 |
2009年 | 21篇 |
2008年 | 33篇 |
2007年 | 33篇 |
2006年 | 28篇 |
2005年 | 21篇 |
2004年 | 21篇 |
2003年 | 24篇 |
2002年 | 13篇 |
2001年 | 3篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 4篇 |
1996年 | 2篇 |
1990年 | 1篇 |
1985年 | 1篇 |
1983年 | 1篇 |
排序方式: 共有616条查询结果,搜索用时 15 毫秒
31.
32.
Megale Costa LJ Soares HP Gaspar HA Trujillo LG Santi PX Pereira RS de Santana TL Pinto FN del Giglio A 《American journal of clinical oncology》2004,27(3):304-306
The number of positive axillary lymph nodes involved by tumor is one of the main prognostic factors for women with locoregional breast cancer (BC) for whom adjuvant chemotherapy is being considered. The prognostic importance of the ratio (P/D) between positive lymph nodes (P) and total dissected lymph nodes (D), previously demonstrated in the high-dose chemotherapy (HDC) setting has not yet been tested, however, in the conventional adjuvant chemotherapy setting. The data of 168 patients who were from 2 institutions and who were treated with adjuvant chemotherapy for BC were retrospectively analyzed, and univariate and multivariate analysis were performed, including the other traditional prognostic factors and P/D ratio as possible predictors of disease free survival (DFS). Disease-free survival for quartile 4 of P/D ratio (ratio >0.30) was statistically different from that for the other quartiles (log-rank test p < 0.001). Mean DFS for this series was not reached as well as for quartiles 1, 2, and 3, while mean DFS for quartile 4 was 44.5 months. In univariate analysis, number of positive lymph nodes (r2 = 0.055; p = 0.023), P/D ratio (r2 = 0.213; p < 0.001), and stage (r2 = 0.105; p = 0.002) were predictive of relapse, while in multivariate analysis, only P/D ratio remained an independent predictor of relapse (r2 = 0.213; p < 0.001). It is concluded that P/D ratio could become a simple, inexpensive, and easily available prognostic factor for patients undergoing conventional chemotherapy for BC. 相似文献
33.
This study examined the impact of changes in self-efficacy over time on HIV-related injection and sex risk behaviors among Puerto Rican drug injectors and crack smokers. Baseline (T1) and 6-month follow-up (T2) data were collected between 1998 and 2000 in New York and Puerto Rico (follow-up rate=79%, 952/1199). Differences in scores on self-efficacy (for risk behaviors) between T1 and T2 were first computed and dichotomized (negative change vs. no/positive change). Those with negative change in self-efficacy were more likely than those with no/positive change to engage in HIV injection and sex risk behaviors at T2. The relationships were significant in multiple logistic regressions after controlling for the effects of potential confounding variables. The findings indicate that improving perceived self-efficacy for risk reduction can help reduce HIV transmission behaviors in high-risk drug users. HIV/AIDS prevention programs should include a focus on enhancing self-efficacy for reducing risk behaviors. 相似文献
34.
We propose some considerations about adolescence, a topic that starts from the know-how of paediatricians and then includes other meanings. One of the most boisterous periods of our life and at the same time one of the most fascinating ones is adolescence. Complex changes characterize this age and these can lead to suffering and confusion even in normal conditions. The age of adolescence is at risk mostly for drug addiction, boredom, uneasiness. A safe basis and a good environment are the necessary conditions enabling adolescents to overcome this critical period for their mental space and to integrate into the adult world so as to reach a new stability. Nevertheless, young people have to confront quick changes, multiple subcultures, the transiency of the intergenerationsl conflict scheme. The dynamics of adolescents reflect some aspects of a society, in which the crisis of the limits and the extreme plurality are the factors that make the elaboration of coherent sense problematic. Today the young encounter many difficulties in relating to their parents due to the complexity of the familiar dynamics. During the long and tiring way to adulthood young people show a huge need of information and attention from the adults. Our duty as paediatricians is to detect, understand and pay attention to these messages. The method is to provide effective information to adolescents. In order to acquire this ability, we think that some conditions are fundamental: professional support and training, listening, networked services. In conclusion, adolescence needs a multiprofessional approach. 相似文献
35.
Cecchin CR Félix TM Magalhães RB Furlanetto TW 《American journal of medical genetics. Part A》2003,(1):52-54
Satoyoshi syndrome (OMIM 600705) is a rare disorder of unknown cause characterized by progressive painful intermittent muscle spasms, amenorrhea, alopecia, malabsorption, and skeletal abnormalities mimicking a skeletal dysplasia. In this report, we describe a Caucasian 12-year-old girl that presented with characteristic manifestations, including alopecia, muscle cramps, and short stature with onset at age 7. Prednisone 60 mg/m(2) every other day and amytriptiline 25 mg QD were administered. After 2 months, alopecia had significantly improved and muscle cramps had almost disappeared, so that glucocorticoid treatment was tapered. Follow-up, 9 months later, showed a normal looking and asymptomatic girl. 相似文献
36.
Robles RR Matos TD Colón HM Sahai H Reyes JC Marrero CA Calderón JM 《Puerto Rico health sciences journal》2003,22(4):369-376
This paper assesses mortality rate for a cohort of drug users in Puerto Rico compared with that of the Island's general population, examining causes of death and estimating relative risk of death. Date and cause of death were obtained from death certificates during 1998. Vital status was confirmed through contact with subjects, family, and friends. HIV/AIDS was the major cause of death (47.7%), followed by homicide (14.6%), and accidental poisoning (6.3%). Females had higher relative risk of death than males in all age categories. Not living with a sex partner and not receiving drug treatment were related to higher mortality due to HIV/AIDS. Drug injection was the only variable explaining relative risk of death due to overdose. Puerto Rico needs to continue developing programs to prevent HIV/AIDS among drug users. Special attention should be given to young women, who appear to be in greatest need of programs to prevent early mortality. 相似文献
37.
38.
Sherry Deren Sung-Yeon Kang Hector M. Colón Rafaela R. Robles 《Journal of urban health》2007,84(2):243-254
This study examined mobility on the airbridge between New York (NY) and Puerto Rico (PR) for Puerto Rican drug users and its relationship to HIV risk. Over 1,200 Puerto Rican injection drug users (IDUs) and crack smokers were recruited by outreach workers in NY and PR; interview data included questions on mobility (lifetime residences and recent trips). Two-thirds of the NY sample had lived in PR; one-quarter of the PR sample had lived in NY; the most commonly sited reasons for moving were family-related. Fewer than 10% had visited the other location in the prior 3 years. Variables related to risk were number of moves, recent travel, and having used drugs in PR (all with p < 0.05). Implications included the need to enhance risk reduction efforts for IDUs in PR and address sexual risk among mobile drug users. 相似文献
39.
40.
Increased Activation Amplitude Levels of Gluteus Medius in Women During Isometric and Dynamic Conditions Following a 4‐week Protocol of Low‐load Eccentric Exercises 下载免费PDF全文