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71.
Risks for incident human papillomavirus infection and low-grade squamous intraepithelial lesion development in young females. 总被引:21,自引:1,他引:20
A B Moscicki N Hills S Shiboski K Powell N Jay E Hanson S Miller L Clayton S Farhat J Broering T Darragh J Palefsky 《JAMA》2001,285(23):2995-3002
CONTEXT: Low-grade squamous intraepithelial lesions (LSILs) have been described as a benign cytological consequence of active human papillomavirus (HPV) replication. Several studies have reported that certain behavioral and biological risks exist for LSIL, suggesting that HPV alone is not sufficient for the development of LSIL. However, because most of these studies have been cross-sectional, it is not known whether behavioral and biological risks are simply risks for HPV infection itself. OBJECTIVE: To prospectively examine risks of incident HPV infection in HPV-negative females and of incident LSIL development in females with HPV infection. DESIGN: Prospective cohort study conducted between 1990-2000, with a median follow-up of 50 months. SETTING AND PARTICIPANTS: Females aged 13 to 21 years who attended 2 family planning clinics in the San Francisco bay area; 496 had prevalent HPV infection and 105 were HPV-negative. MAIN OUTCOME MEASURE: Incident development of HPV infection and LSIL, analyzed by various demographic, behavioral, and clinical risk factors. RESULTS: Fifty-four incident HPV infections occurred in the 105 females who were HPV-negative at study entry (median duration of follow-up for those who remained HPV-negative was 26 months). Multivariable analysis showed that risks of HPV included sexual behavior (relative hazard [RH], 10.10; 95% confidence interval [CI], 3.24-31.50 per new partner per month), history of herpes simplex virus (RH, 3.54; 95% CI, 1.37-9.10), and history of vulvar warts (RH, 2.73; 95% CI, 1.27-5.87). Current use of oral contraceptives had a significantly protective effect (RH, 0.49; 95% CI, 0.28-0.86). Among the 496 individuals who were HPV-positive at baseline or in follow-up, there were 109 incident cases of LSIL during the follow-up interval, with a median follow-up time of 60 months for those who never developed LSIL. Human papillomavirus infection was the most significant risk factor for development of LSIL. The multivariable model showed the following risks for LSIL: HPV infection for less than 1 year (RH, 7.40; 95% CI, 4.74-11.57); HPV infection for 1 to 2 years (RH, 10.27; 95% CI, 5.64-18.69); HPV infection for 2 to 3 years (RH, 6.11; 95% CI, 1.86-20.06); and daily cigarette smoking (RH, 1.67; 95% CI, 1.12-2.48). CONCLUSION: Our results indicate distinct risks for HPV and LSIL. In addition, most women with HPV infection in our study did not develop LSIL within a median follow-up period of 60 months. These findings underscore the hypothesis that certain biological risks thought to be associated with LSIL are, in fact, risks for acquisition of HPV. Cigarette smoking was a risk specific to LSIL, supporting the role of tobacco in neoplastic development. 相似文献
72.
一阶导数差示脉冲极谱法的建立及在药物分析中的应用 总被引:11,自引:0,他引:11
本文研究了一阶导数差示脉冲极谱法,并将其运用于扑尔敏、氟哌啶醇、维生素B6及其制剂的定量分析中。方法简便、快速、灵敏、结果准确。 相似文献
73.
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75.
A randomized prospective comparison of oral versus intraperitoneal ofloxacin as the primary treatment of CAPD peritonitis 总被引:1,自引:0,他引:1
Ignatius KP CHENG SL LUI GX FANG PY CHAU SW CHENG Frances H CHIU TM CHAN WK LO BY CHOY CY LO 《Nephrology (Carlton, Vic.)》1997,3(6):431-435
Summary: Oral ofloxacin has been successfully used in our centres for the primary treatment of peritonitis complicating continous ambulatory peritoneal dialysis (CAPD). In view of the progressive rise in the resistance rate to ofloxacin among peritoneal bacterial isolates, a study was conducted to determine if oral ofloxacin remains a viable first line treatment for CAPD peritonitis in our centres and if the result can be improved by changing from an oral to an intraperitoneal (i.p.) route. In patients on three 2 L daily CAPD exchanges, ofloxacin given at the i.p. dosage of 200 mg loading followed by 25 mg/L of peritoneal dialysate achieved overnight trough peritoneal levels which are at least four times the minimal 90% inhibitory concentration (MIC90) of most bacterial pathogens without significant accumulation in the systemic circulation. This i.p. dosage was therefore chosen for the clinical study and the result was compared to that using ofloxacin given in the oral dosage of 400 mg loading followed by 300 mg once daily as maintenance. of all the recruited episodes, 35 were eligible for analysis. the overall primary cure rate including primary failures and relapses was 55.6% (10/18) in the oral treatment group and 70.6% (12/17) in the i.p. treatment group. the corresponding figures for gram positive bacterial (g +) infections were 36.4% and 50%, for gram negative bacterial (g -) infections were 66.7 and 80% and for culture negative infections were 75 and 80%. In culture positive cases, all treatment failures were due to resistant infections which were observed in 42.3% of all bacterial isolates, 47.1% of g + isolates and 33.3% of g - isolates. Due to the high background level of bacterial resistance among our CAPD population, ofloxacin monotherapy given either by the oral or the i.p. route can no longer be recommended for the primary treatment of CAPD peritonitis. 相似文献
76.
Quality systems and total process control in blood banking 总被引:3,自引:0,他引:3
Blood banking has dramatically changed in the past few years. Is the old business hierarchy and medical model for management still workable? How do we want to organize our work today for success in the future? Implementation of quality systems may seem overwhelmingly complex at this time to many blood banking establishments. However, by methodically adhering to the requirements of organization development described in this review, blood centers can achieve goals of quality improvement and TPC. The FDA and the pharmaceuticals and medical device industries have set the direction and provided guidance to blood establishments. The AABB, American Society for Quality Control, the American Society for Training and Development, and numerous other professional organizations can contribute information and materials. The FDA's document on quality assurance and the CFR are the basic texts guiding the approach presented in this paper. The organization's structure and processes may need to be reengineered to meet the requirements of a culture based on quality and process control. 相似文献
77.
The procoagulant subcellular matrix of stimulated endothelial cells that contains tissue factor (TF) was used to investigate the mechanism by which TF pathway inhibitor (TFPI) inhibits thrombin formation initiated by TF/factor VIIa (FVIIa) under flow conditions. Purified coagulation factors VII, X, and V and prothrombin were perfused at a wall shear rate of 100 s-1 through a flow chamber containing a coverslip covered with matrix of cultured human umbilical vein endothelial cells. This resulted in a TF- and FVII-dependent FXa and thrombin generation as measured in the effluent at the outlet of the system. Inhibition of this TF/FVIIa-triggered thrombin formation by TFPI purified from plasma was dependent on the amount of TF present on the endothelial cell matrix. The rate of prothrombinase assembly and steady-state levels of thrombin formation were decreased by TFPI. Because persistent albeit decreased steady-state levels of thrombin formation occurred in the presence of TFPI, we conclude that plasma- TFPI does not inhibit FXa present in the prothrombinase complex. The addition of FIX and FVIII to perfusates containing FVII and FX increased the FXa generation on endothelial matrices, and counteracted the inhibition of thrombin formation on endothelial cell matrices by TFPI. Our data provide further evidence for the hypothesis that the rapid inactivation of TF/FVIIa by TFPI in combination with the absence of either FVIII or FIX causes the bleeding tendency of patients with hemophilia A or B. 相似文献
78.
Phase II trial of 2-chlorodeoxyadenosine for the treatment of cutaneous T-cell lymphoma [see comments] 总被引:1,自引:0,他引:1
Kuzel TM; Hurria A; Samuelson E; Tallman MS; Roenigk HH Jr; Rademaker AW; Rosen ST 《Blood》1996,87(3):906-911
We investigated the efficacy of 2-chlorodeoxyadenosine (2-CdA) therapy in patients with mycosis fungoides (MF) and the Sezary syndrome (SS). Between February 1991 and November 1993, 21 patients with relapsed or refractory MF/SS were treated with 2-CdA. 2-CdA was administered by continuous intravenous infusion at a dose of 0.1 mg/kg/d for 7 days initially (13 patients), but was subsequently reduced to 5 days (nine patients) due to hematologic toxicity. All patients had failed to respond to at least one prior treatment for MF/SS (median number of total prior therapies, five; median number of systemic prior therapies, three) and had an Eastern Cooperative Oncology Group performance status of two or better. Cycles were administered at 28-day intervals. Assessable patients received at least 5 days of 2-CdA. Fourteen patients received more than one cycle of 2-CdA. An overall response rate of 28% was achieved. Three patients (14%) had a complete response with a median duration of 4.5 months (range, 2.5 to 16). Three (14%) had a partial response with a median duration of 2 months (range, 2 to 4). Fifteen patients (72%) had no response. The most significant toxicities encountered were bone marrow suppression (62% of patients) and infectious complications (62% of patients). Thirty-eight percent of patients experienced no toxicity from 2-CdA. 2-CdA has activity as a single agent in patients with previously treated relapsed MF/SS. Studies in less heavily pretreated individuals with 2-CdA alone or in combination will be undertaken. 相似文献
79.
Muhammad A. Alvi Darragh G. McArt Paul Kelly Marc-Aurel Fuchs Matthew Alderdice Clare M. McCabe Victoria Bingham Claire McGready Shailesh Tripathi Frank Emmert-Streib Maurice B. Loughrey Stephen McQuaid Perry Maxwell Peter W. Hamilton Richard Turkington Jacqueline A. James Richard H. Wilson Manuel Salto-Tellez 《Oncotarget》2015,6(25):20863-20874
80.
Molecular classification of non-invasive breast lesions for personalised therapy and chemoprevention
Niamh Buckley David Boyle Darragh McArt Gareth Irwin D. Paul Harkin Tong Lioe Stephen McQuaid Jacqueline A. James Perry Maxwell Peter Hamilton Paul B. Mullan Manuel Salto-Tellez 《Oncotarget》2015,6(41):43244-43254
Breast cancer screening has led to a dramatic increase in the detection of pre-invasive breast lesions. While mastectomy is almost guaranteed to treat the disease, more conservative approaches could be as effective if patients can be stratified based on risk of co-existing or recurrent invasive disease.Here we use a range of biomarkers to interrogate and classify purely non-invasive lesions (PNL) and those with co-existing invasive breast cancer (CEIN). Apart from Ductal Carcinoma in situ (DCIS), relative homogeneity is observed. DCIS contained a greater spread of molecular subtypes. Interestingly, high expression of p-mTOR was observed in all PNL with lower expression in DCIS and invasive carcinoma while the opposite expression pattern was observed for TOP2A.Comparing PNL with CEIN, we have identified p53 and Ki67 as predictors of CEIN with a combined PPV and NPV of 90.48% and 43.3% respectively. Furthermore, HER2 expression showed the best concordance between DCIS and its invasive counterpart.We propose that these biomarkers can be used to improve the management of patients with pre-invasive breast lesions following further validation and clinical trials. p53 and Ki67 could be used to stratify patients into low and high-risk groups for co-existing disease. Knowledge of expression of more actionable targets such as HER2 or TOP2A can be used to design chemoprevention or neo-adjuvant strategies. Increased knowledge of the molecular profile of pre-invasive lesions can only serve to enhance our understanding of the disease and, in the era of personalised medicine, bring us closer to improving breast cancer care. 相似文献