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排序方式: 共有1286条查询结果,搜索用时 31 毫秒
1.
Rebecca P. Ang Robert M. Klassen Wan Har Chong Vivien S. Huan Isabella Y.F. Wong Lay See Yeo Lindsey L. Krawchuk 《Journal of adolescence》2009,32(5):1225-1237
We provide further evidence for the two-factor structure of the 9-item Academic Expectations Stress Inventory (AESI) using confirmatory factor analysis on a sample of 289 Canadian adolescents and 310 Singaporean adolescents. Examination of measurement invariance tests the assumption that the model underlying a set of scores is directly comparable across groups. This study also examined the cross-cultural validity of the AESI using multigroup confirmatory factor analysis across both the Canadian and Singaporean adolescent samples. The results suggested cross-cultural invariance of form, factor loadings, and factor variances and covariances of the AESI across both samples. Evidence of AESI's convergent and discriminant validity was also reported. Findings from t-tests revealed that Singaporean adolescents reported a significantly higher level of academic stress arising from self expectations, other expectations, and overall academic stress, compared to Canadian adolescents. Also, a larger cross-cultural effect was associated with academic stress arising from other expectations compared with academic stress arising from self expectations. 相似文献
2.
Clinical aspects of pelvic inflammatory disease 总被引:2,自引:0,他引:2
Pelvic inflammatory disease (PID) is a common and poorly managed condition.
Untreated or inadequately treated, it leads to tubal infertility, ectopic
pregnancy and chronic pelvic pain. Diagnostic difficulties are compounded
by the wide variety of clinical presentations and the insensitivity and
poor specificity of laboratory tests. Better recognition of mild and
atypical disease needs a high index of suspicion whenever young, sexually
active women present with gynaecological symptoms. Laparoscopy supplemented
by microbiological tests and fimbrial minibiopsy should be regarded as the
diagnostic 'gold standard' for research studies; new studies are required
to identify techniques which might reduce under- and over-diagnosis. Early
treatment reduces the risk of an adverse effect on fertility. Any
therapeutic regimen selected should be effective against the common
aetiological agents Chlamydia trachomatis, Neisseria gonorrhoeae, genital
mycoplasmas and aerobic and anaerobic bacteria. Since at least 60% of cases
of PID can be attributed to infection with a sexually transmitted organism,
partner notification forms an essential part of management.
相似文献
3.
L H Anderson T L McDonald G M Thiele L W Klassen 《Journal of clinical laboratory analysis》1992,6(3):113-118
Different assay systems have been used to quantitate lymphokine-induced natural cytotoxic activity as a measure of immune status. This study compares the effects of inducing cytotoxicity in a bulk culture system, where effector cells are transferred to a micro culture well for assay, to a micro culture system where the effector cells are not transferred. The effector/target ratio for both the bulk and micro culture systems was calculated using the number of viable effector cells present at the time of target cell addition. After overnight incubation with interleukin-2 (IL-2), the lytic activity of murine spleen cells to targets using a micro culture system was increased two-fold over the bulk culture method. This increase was amplified further after 5 days of activation with IL-2, in that the micro culture system resulted in a four-fold increase in cytotoxic activity. The loss of some adherent cells in the bulk culture system did not explain the overall decrease in recovered cytotoxicity. The difference appeared to be related to cell loss during centrifugation. Therefore, the E/T ratios are different in the two systems if not corrected for the number of viable cells. 相似文献
4.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
5.
6.
J Ansell V Klassen R Lew S Ball M Weinstein T VanderSalm N Okike I Gratz J Leslie A Roberts 《The Journal of thoracic and cardiovascular surgery》1992,104(1):117-123
The effectiveness of prophylactic desmopressin acetate in reducing hemorrhage after cardiopulmonary bypass operations is controversial. We conducted a prospective, randomized, placebo-controlled, double-blind trial to determine its effectiveness and safety in such patients. Eighty-three evaluable patients undergoing valvular heart operations were randomized to receive desmopressin (0.3 microgram/kg) (41) or placebo (42) after cardiac bypass. Demographic characteristics were similar in both groups. There was no significant difference in total 24-hour blood loss between groups (desmopressin 1064.8 +/- 647.1 ml versus placebo 844.4 +/- 507.6 ml; p greater than 0.05), or in the requirement for red blood cell, platelet, or fresh frozen plasma transfusion, or for reexploration for control of hemorrhage. Neither was there a difference in the occurrence of thrombotic complications between groups. Analysis of factor VIII activity, von Willebrand factor, or von Willebrand factor multimers failed to show significant correlations with blood loss or differences between groups except for factor VIII activity, which was significantly higher in the desmopressin group 1 hour after operation than in the placebo group. A detailed comparative analysis of similar trials to determine the reasons for different outcomes suggests that desmopressin should not be used routinely as a prophylactic agent to reduce postsurgical hemorrhage, but that it may be beneficial when used in patients who already manifest excessive bleeding postoperatively. 相似文献
7.
8.
W P Vaughan J D Dennison E C Reed L Klassen T R McGuire W G Sanger P P Kumar P I Warkentin B G Gordon P J Bierman 《Bone marrow transplantation》1991,8(6):489-495
Twenty-four patients between the ages of 8 and 48 years (median 27.5) with high-risk for relapse hematologic malignancy received a marrow transplant from an HLA and MLC compatible sibling donor after chemotherapy with busulfan, 4 mg/kg/day for 4 days by mouth, cyclophosphamide 60 mg/kg/day i.v. for 2 days, and etoposide 60 mg/kg i.v. over 4 h on the first day of cyclophosphamide treatment (BU/CY/VP). Toxicity consisted of mucositis, skin rash, and nausea and vomiting in all patients, transient fever thought to be due to etoposide administration in 16/24 (67%) patients, and clinical veno-occlusive disease (VOD) of the liver in 4/24 (17%). There were nine deaths from causes other than recurrent disease in the first 100 days after transplant and two deaths after day 100, a total transplant mortality of 11/24 (46%). Three patients relapsed, but 10/24 (40%) remain alive and disease free 26-182 weeks (median 60 weeks) from transplant. These results compare favorably with results in a group of 12 similar risk patients treated with total body irradiation (TBI) containing regimens during an overlapping time period. Six of the TBI patients have had persistent or recurrent disease and only two (17%) are currently alive and disease free. The probability of disease persistence or relapse is 67% in the TBI group and 20% in the BU/CY/VP group (p less than 0.02). 相似文献
9.
Incidence and determinants of moderate COPD (GOLD II) in male smokers aged 40–65 years: 5-year follow up
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Roeland MM Geijer Alfred PE Sachs Theo JM Verheij Philippe L Salom Jan-Willem J Lammers Arno W Hoes 《The British journal of general practice》2006,56(530):656-661
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is a major health problem with an estimated prevalence of 10-15% among smokers. The incidence of moderate COPD, as defined by the Global Initiative for Chronic Obstructive Lung Disease (GOLD), is largely unknown. AIM: To determine the cumulative incidence of moderate COPD (forced expiratory volume in 1 second/forced vital capacity ratio [FEV1/FVC] <0.7 and FEV1 <80% predicted) and its association with patient characteristics in a cohort of male smokers. DESIGN: Prospective cohort study. SETTING: The city of IJsselstein, a small town in the Netherlands. METHOD: Smokers aged 40-65 years who were registered with local GPs, participated in a study to identify undetected COPD. Baseline measurements were taken in 1998 of 399 smokers with normal spirometry (n = 292) or mild COPD (FEV1/FVC <0.7 and FEV1 >or=80% predicted, n = 107) and follow-up measurements were conducted in 2003. RESULTS: After a mean follow-up of 5.2 years, 33 participants developed moderate COPD (GOLD II). This showed an estimated cumulative incidence of 8.3% (95% CI = 5.8 to 11.4) and a mean annual incidence of 1.6%. No participant developed severe airflow obstruction. The risk of developing moderate COPD in smokers with baseline mild COPD (GOLD I) was five times higher than in those with baseline normal spirometry (one in five versus one in 25). CONCLUSIONS: In a cohort of middle-aged male smokers, the estimated cumulative incidence of moderate COPD (GOLD II) over 5 years was relatively high (8.3%). Age, childhood smoking, cough, and one or more GP contacts for lower respiratory tract problems were independently associated with incident moderate COPD. 相似文献
10.
Chest radiography in general practice: indications, diagnostic yield and consequences for patient management
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Anouk M Speets Yolanda van der Graaf Arno W Hoes Sandra Kalmijn Alfred PE Sachs Matthieu JCM Rutten Jan Willem C Gratama Alexander D Montauban van Swijndregt Willem PThM Mali 《The British journal of general practice》2006,56(529):574-578
BACKGROUND: Chest radiography (CXR) is frequently performed in Western societies. There is insufficient knowledge of its diagnostic value in terms of changes in patient management decisions in primary care. AIM: To assess the influence of CXR on patient management in general practice. DESIGN OF STUDY: Prospective cohort study. SETTING: Seventy-eight GPs and three general hospitals in the Netherlands. METHOD: Patients (n = 792) aged > or =18 years referred by their GPs for CXR were included. The main outcome was change in patient management assessed by means of questionnaires filled in by GPs before and after CXR. RESULTS: Mean age of the patients was 57.3+/-16.2 years and 53% were male. Clinically relevant abnormalities were found in 24% of the CXRs. Patient management changed in 60% of the patients following CXR. Main changes included: fewer referrals to a medical specialist (from 26 to 12%); reduction in initiation or change in therapy (from 24 to 15%); and more frequent reassurance (from 25 to 46%). However, this reassurance was not perceived as such in a quarter of these patients. A change in patient management occurred significantly more frequently in patients with complaints of cough (67%), those who exhibited abnormalities during physical examination (69%), or those with a suspected diagnosis of pneumonia (68%). CONCLUSION: Patient management by the GP changed in 60% of patients following CXR. CXR substantially reduced the number of referrals and initiation or change in therapy, and more patients were reassured by their GP. Thus, CXR is an important diagnostic tool for GPs and seems a cost-effective diagnostic test. 相似文献