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991.
992.
Huebler M Koster A Redlin M Boettcher W Stiller B Nürnberg I Kuppe H Hetzer R 《Journal of cardiac surgery》2005,20(3):261-263
Even in infants and small children, ventricular assist devices have an emerging role in the treatment of congenital and postcardiotomy heart failure. Extracorporeal pneumatic pulsatile devices are considered the strategy of choice if long-lasting bridge to recovery or transplantation is expected. However, complete explantation of the device may be complicated by hemorrhage and subsequent transfusions due to the establishment of CPB. The present case demonstrates successful weaning and complete removal of an apical venting pulsatile LVAD in a 4-kg infant without the employment of CPB. 相似文献
993.
BACKGROUND: Surgical management of patients with metastatic or recurrent rectal cancer remains controversial. Self-expanding metal stents are increasingly used for palliative treatment of advanced tumors, although long-term results are not yet available. METHODS: Between 1996 and 2003, 521 patients underwent surgery for rectal neoplasms. In the same time period, self-expanding metal stents were used for palliation of 34 patients with malignant rectal obstruction and incurable disease. The outcome of the patients was analyzed retrospectively. RESULTS: Rectal stents were successfully placed in 33 of 34 patients (97%) without major complications. Early failure occurred in 7 patients (21%) because of stent migration, pain, or incontinence. Long-term success with a mean patency of 5.3 months was observed in 26 patients (79%), but restenting was required in 2 patients. Despite the initial success of stenting, a colostomy was created in 2 other patients after 3.4 months and 9.2 months because of incontinence and rectovesical fistula. Overall, 6 of 33 patients (18%) underwent palliative surgery because of early complications (n = 4) or long-term failure of stent treatment (n = 2). CONCLUSIONS: Self-expanding metal stents are useful to avoid a colostomy in selected patients with incurable rectal cancer and limited life expectancy. Nonetheless, a considerable number (18%) of patients will require surgical palliation because of failure of stent treatment. 相似文献
994.
995.
Hoeltl W Müller MM Lunglmayr G 《The Journal of urology》2005,173(6):2205; author reply 2205-2205; author reply 2206
996.
Schmelz HU Port M Hauck EW Schwerer MJ Weidner W Sparwasser C Abend M 《BJU international》2005,96(1):158-163
OBJECTIVE: To correlate the number of tumour-infiltrating T lymphocytes (TILs) with the extent of apoptosis in testicular germ cell tumours, as TILs are considered to be a favourable prognostic factor of human testicular tumours, especially of seminomas, but the mechanism by which TIL contribute to an improved outcome is unclear. MATERIALS AND METHODS: Tissue samples from 47 patients with nonseminomatous germ cell tumour (NSGCT) and 15 with seminomatous GCT were investigated immunohistochemically for lymphocyte infiltration and apoptosis. The apoptotic index (AI) was assessed in various categories (DNA condensation and fragmentation) using in-situ end-labelling to identify typical apoptotic DNA strand breaks, and nuclear staining to identify typical apoptotic morphology. RESULTS: In seminomatous GCT there was no correlation between the number of TILs and any AI. In NSGCT there was only a relationship between lymphoid infiltration and those AIs showing morphological criteria of apoptosis in a small subgroup of NSGCT, i.e. metastasized embryonal cell carcinomas. Only 1.2% (AI, chromatin condensation) and 0.8% (AI, fragmentation and condensation) of all tumour cells showed these features of apoptosis. The overall AI in NSGCT was 7.9%. CONCLUSIONS: TILs do not seem to induce apoptosis in testicular tumours. Embryonal cell carcinomas might be susceptible to lymphocyte attack, resulting in apoptosis of the tumour cell. The mechanisms of interaction between lymphocytes and testis tumour cells need further investigation. 相似文献
997.
998.
Biebl M Hakaim AG Lau LL Oldenburg WA Klocker J Neuhauser B Paz-Fumagalli R McKinney JM Stockland A 《Vascular》2005,13(1):16-22
The purpose of this study was to evaluate the incidence and durability of additional proximal cuffs during endovascular abdominal aortic aneurysm repair (EVAR). A retrospective review of 90 EVAR patients was conducted. Postoperative survival, proximal sealing zone-related complications, and secondary procedures were analyzed. Additional proximal cuffs were used in 11%. Their use did not affect postoperative survival (p = .58), type I endoleak rate (4.4%; p = .19), or the need for sealing zone-related secondary procedures (6.3%; p = .38) compared with patients without cuff placement but was related to a higher cumulative graft migration rate (2.2% overall p = .02). Two patients (2.5%; p = .79) underwent conversion to open surgery, both for proximal sealing zone-related complications. Application of proximal cuffs appears to be an effective intraoperative adjunctive procedure to achieve a proximal seal during EVAR, with favorable midterm results. However, the risk of late endograft migrations may be elevated in this group. 相似文献
999.
1000.
Randomized trials stopped early for benefit: a systematic review 总被引:17,自引:2,他引:15
Montori VM Devereaux PJ Adhikari NK Burns KE Eggert CH Briel M Lacchetti C Leung TW Darling E Bryant DM Bucher HC Schünemann HJ Meade MO Cook DJ Erwin PJ Sood A Sood R Lo B Thompson CA Zhou Q Mills E Guyatt GH 《JAMA》2005,294(17):2203-2209
Context Randomized clinical trials (RCTs) that stop earlier than planned because of apparent benefit often receive great attention and affect clinical practice. Their prevalence, the magnitude and plausibility of their treatment effects, and the extent to which they report information about how investigators decided to stop early are, however, unknown. Objective To evaluate the epidemiology and reporting quality of RCTs involving interventions stopped early for benefit. Data Sources Systematic review up to November 2004 of MEDLINE, EMBASE, Current Contents, and full-text journal content databases to identify RCTs stopped early for benefit. Study Selection Randomized clinical trials of any intervention reported as having stopped early because of results favoring the intervention. There were no exclusion criteria. Data Extraction Twelve reviewers working independently and in duplicate abstracted data on content area and type of intervention tested, reporting of funding, type of end point driving study termination, treatment effect, length of follow-up, estimated sample size and total sample studied, role of a data and safety monitoring board in stopping the study, number of interim analyses planned and conducted, and existence and type of monitoring methods, statistical boundaries, and adjustment procedures for interim analyses and early stopping. Data Synthesis Of 143 RCTs stopped early for benefit, the majority (92) were published in 5 high-impact medical journals. Typically, these were industry-funded drug trials in cardiology, cancer, and human immunodeficiency virus/AIDS. The proportion of all RCTs published in high-impact journals that were stopped early for benefit increased from 0.5% in 1990-1994 to 1.2% in 2000-2004 (P<.001 for trend). On average, RCTs recruited 63% (SD, 25%) of the planned sample and stopped after a median of 13 (interquartile range [IQR], 3-25) months of follow-up, 1 interim analysis, and when a median of 66 (IQR, 23-195) patients had experienced the end point driving study termination (event). The median risk ratio among truncated RCTs was 0.53 (IQR, 0.28-0.66). One hundred thirty-five (94%) of the 143 RCTs did not report at least 1 of the following: the planned sample size (n = 28), the interim analysis after which the trial was stopped (n = 45), whether a stopping rule informed the decision (n = 48), or an adjusted analysis accounting for interim monitoring and truncation (n = 129). Trials with fewer events yielded greater treatment effects (odds ratio, 28; 95% confidence interval, 11-73). Conclusions RCTs stopped early for benefit are becoming more common, often fail to adequately report relevant information about the decision to stop early, and show implausibly large treatment effects, particularly when the number of events is small. These findings suggest clinicians should view the results of such trials with skepticism. 相似文献