首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1731篇
  免费   130篇
  国内免费   5篇
耳鼻咽喉   16篇
儿科学   118篇
妇产科学   43篇
基础医学   276篇
口腔科学   24篇
临床医学   213篇
内科学   439篇
皮肤病学   18篇
神经病学   152篇
特种医学   34篇
外科学   193篇
综合类   10篇
一般理论   1篇
预防医学   106篇
眼科学   19篇
药学   104篇
中国医学   1篇
肿瘤学   99篇
  2023年   7篇
  2021年   28篇
  2020年   17篇
  2019年   28篇
  2018年   52篇
  2017年   34篇
  2016年   49篇
  2015年   45篇
  2014年   49篇
  2013年   85篇
  2012年   96篇
  2011年   88篇
  2010年   48篇
  2009年   38篇
  2008年   77篇
  2007年   64篇
  2006年   80篇
  2005年   80篇
  2004年   52篇
  2003年   82篇
  2002年   78篇
  2001年   69篇
  2000年   56篇
  1999年   61篇
  1996年   8篇
  1994年   9篇
  1993年   12篇
  1992年   43篇
  1991年   18篇
  1990年   29篇
  1989年   34篇
  1988年   29篇
  1987年   36篇
  1986年   31篇
  1985年   39篇
  1984年   19篇
  1983年   9篇
  1982年   7篇
  1981年   12篇
  1980年   8篇
  1979年   17篇
  1978年   14篇
  1977年   17篇
  1976年   11篇
  1975年   9篇
  1974年   9篇
  1973年   7篇
  1971年   7篇
  1969年   10篇
  1967年   11篇
排序方式: 共有1866条查询结果,搜索用时 31 毫秒
1.

Background

Radium 223 was introduced for metastatic castration-resistant prostate cancer based on the results of a randomized controlled trial showing risk reduction for death and skeletal events. Our aim was to evaluate the outcome of patients receiving radium 223 in a real-world setting.

Patients and Methods

We conducted a multicenter retrospective analysis in the Triveneto region of Italy.

Results

One hundred fifty-eight patients received radium 223 in our region. After a median follow-up of 9.5 months, 75 patients died. The median overall survival (OS) was 14.2 months, and the median progression-free survival (PFS) was 6.2 months. Seventy-one (45%) patients achieved progression as best response. Thirty-seven (23%) patients stopped the treatment early because of progression. Eastern Cooperative Oncology Group performance status was prognostic for OS (18.4 vs. 12.3 vs. 7.5 months; 0 vs. 1, P = .0062; 0 vs. 2, P = .0002), whereas previous prostatectomy or docetaxel exposure were not. A neutrophil to lymphocytes ratio ≥ 3 significantly impacted OS (18.1 vs. 9.7 months; P < .001) and slightly impacted PFS (6.6 vs. 5.6 months; P = .05). Patients with a baseline alkaline phosphatase (ALP) value ≥ 220 U/L had worse OS and PFS (24.1 vs. 10.5 months; 7.2 vs. 5.5 months; P < .001). Patients with changes in ALP value achieved better OS (P = .029) and PFS (P = .002). There was no difference according to the line of therapy (0 vs. ≥ 1; P = .490). The main grade 3/4 toxicities were anemia, asthenia, and thrombocytopenia.

Conclusion

This large real-world report confirms comparable OS and PFS data when compared with the pivotal study, as well as the predictive role of ALP and neutrophil to lymphocytes ratio. The definition of the optimal position of radium 223 in the treatment of metastatic castration-resistant prostate cancer has still to be defined.  相似文献   
2.
Newer policies of community care for those with disabilities have resulted in the home becoming the usual site of care. Policy makers must now give attention to the needs of those at home giving this care. This article explores the constraints on sociability opportunities of 73 mothers who were caring for children with disabilities. These opportunities are often built into leisure pursuits for women without caring responsibilities. However, choice of out-of-house leisure activity was circumscribed for the mothers in this study and their reported leisure activities revolved around home and neighbourhood. Even these sites offered limited scope for sociability because of the way in which caring affected domestic space and because of the characteristics of the modern Australian suburb. It is argued in this paper that personal time and personal domestic space are needed by care-givers so their sociability needs can be fulfilled. An understanding of the constraints imposed by use of the home as a place of care may make possible the planning of a rearrangement of domestic space to increase sociability opportunities for carers.  相似文献   
3.
Objectives: To illustrate endoscopic techniques used in the treatment of esthesioneuroblastoma and to advocate this method of management followed by radiation therapy in selected cases. Methods: A retrospective case series of 10 patients with esthesioneuroblastomas treated between 1999 and 2004 at a tertiary referral center using endonasal techniques. Results: Mean age of patients at presentation was 56.2 years (median 57 years). Seven patients were female and 3 patients were male. Kadish staging at presentation was: A - 3 patients, B - 5 patients, C - 2 patients. Dulguerov stage at presentation was: T1 - 4 patients, T2 - 4 patients, T3 - 2 patients. The period of follow-up ranged from 11 months to 74 months (mean 38.1 months, median 39 months). To date no recurrence has developed in any patient. Conclusions: Our experience suggests that endoscopic surgery can be an effective method of management. Strict attention to selection criteria, careful surgical techniques, and regular follow-up are key elements for success.  相似文献   
4.
OBJECTIVE: To determine whether hyperinsulinemia has a negative effect on uterine blood supply in patients with polycystic ovary syndrome (PCOS). METHODS: Sixty-three patients with normal body mass index were included prospectively in the study: 48 had clinical and hormonal features of PCOS and 15 were normo-ovulatory. All patients underwent Doppler flow measurement of the uterine artery, and determination of serum concentrations of luteinizing hormone, follicle stimulating hormone, prolactin, estradiol, androgens, insulin and C-peptide during the early follicular phase of the menstrual cycle. The 48 PCOS-patients were divided into two groups according to the pulsatility index (PI) value of the uterine artery: Group 1, PI < 3; Group 2, PI >or= 3 and the groups were compared. RESULTS: The mean PI of the uterine artery (3.01 +/- 1.0 vs. 1.93 +/- 0.3, respectively) and fasting levels of insulin (50.9 +/- 9.3 vs. 40.3 +/- 10.9) and C-peptide (366.9 +/- 118.4 vs. 243.6 +/- 120.3) of PCOS-patients were significantly higher than those of the control group. No correlation was found between insulinemia and C-peptide and PI of the uterine artery and no significant difference was found in insulin and C-peptide levels among the two groups of PCOS-affected patients. Only the serum level of dehydroepiandrosterone sulfate was significantly higher in Group 2, and a direct correlation was found between PI values of the uterine artery and DHEAS plasma levels. CONCLUSION: Insulin and C-peptide do not seem to interfere with uterine perfusion in PCOS-affected patients.  相似文献   
5.
6.
7.
8.
A pregnancy obtained in a patient with 46XY gonadal dysgenesis (Swyer's syndrome) after ovum donation and IVF/ET is described. The efficacy of this technique in overcoming particular cases of otherwise irreversible infertility is discussed.  相似文献   
9.
OBJECTIVE: To investigate the association between the use of fluoroquinolone agents and the risk of tendinitis in a large population-based case-control study. METHODS: The study was performed by linking automated health databases from the Region of Lombardia, Italy. Cases were patients aged > or =18 years who had a hospital discharge diagnosis of non-traumatic tendinitis in 2002-3. For each case, up to five controls were randomly selected among those eligible for inclusion in the study. A conditional logistic regression model was used to estimate the odds ratio of tendinitis associated with the current, recent and past use of fluoroquinolones. Odds ratios were adjusted for exposure to other antibacterials and other drugs. RESULTS: 22,194 cases and 104,906 controls met the inclusion criteria. Current use of fluoroquinolones significantly increased the risk of tendon disorders as a whole (odds ratio [OR] = 1.7; 95% CI 1.4, 2.0), tendon rupture (OR = 1.3; 95% CI 1.0, 1.8) and rupture of the Achilles' tendon (OR = 4.1; 95% CI 1.8, 9.6). Concomitant use of corticosteroids and fluoroquinolones increased the risk of both tendon rupture (OR = 3.1; 95% CI 1.5, 6.3) and rupture of the Achilles' tendon (OR = 43.2; 95% CI 5.5, 341.1). DISCUSSION: Evidence that exposure to fluoroquinolones is associated with the sudden occurrence of tendinitis is supported by this large population-based study. We can estimate that a single case of rupture of the Achilles' tendon would occur for every 5958 persons treated with fluoroquinolones (95% CI 2148, 23,085). The corresponding number needed to harm is 979 (95% CI 122, 9172) for patients who concomitantly use corticosteroids and 1638 (95% CI 351, 8843) for those aged >60 years. CONCLUSION: Clinicians should be aware of this adverse effect, and the increased risk for fluoroquinolone-associated tendinitis in elderly patients with corticosteroid use must be considered when these agents are prescribed.  相似文献   
10.
Penicillin acylase (EC 3.5.1.11) from E. coli, both in solution and immobilized on solid supports, has been commercially exploited for the large scale production of 6-aminopenicillanic acid (6-APA), which is an important intermediate for the manufacturing of semisynthetic penicillins. In this paper a very simple procedure of penicillin acylase purification is reported, which employs only one affinity chromatographic step (Sepharose-phenylacetic column). The enzyme was obtained at a high degree of purity and could be used for immobilization on partially hydrolyzed and activated nylon. Since the support is chemically inert and mechanically stable the catalyst can be used several times without any significant loss of activity, making the process of great commercial importance.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号