全文获取类型
收费全文 | 794篇 |
免费 | 36篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 37篇 |
妇产科学 | 10篇 |
基础医学 | 65篇 |
口腔科学 | 26篇 |
临床医学 | 108篇 |
内科学 | 194篇 |
皮肤病学 | 32篇 |
神经病学 | 21篇 |
特种医学 | 144篇 |
外科学 | 54篇 |
综合类 | 28篇 |
预防医学 | 42篇 |
眼科学 | 4篇 |
药学 | 18篇 |
1篇 | |
肿瘤学 | 48篇 |
出版年
2023年 | 2篇 |
2022年 | 5篇 |
2021年 | 7篇 |
2020年 | 12篇 |
2019年 | 7篇 |
2018年 | 15篇 |
2017年 | 6篇 |
2016年 | 11篇 |
2015年 | 17篇 |
2014年 | 20篇 |
2013年 | 22篇 |
2012年 | 18篇 |
2011年 | 25篇 |
2010年 | 30篇 |
2009年 | 33篇 |
2008年 | 29篇 |
2007年 | 33篇 |
2006年 | 29篇 |
2005年 | 24篇 |
2004年 | 21篇 |
2003年 | 11篇 |
2002年 | 23篇 |
2001年 | 15篇 |
2000年 | 18篇 |
1999年 | 12篇 |
1998年 | 41篇 |
1997年 | 45篇 |
1996年 | 38篇 |
1995年 | 19篇 |
1994年 | 31篇 |
1993年 | 25篇 |
1992年 | 12篇 |
1991年 | 10篇 |
1990年 | 15篇 |
1989年 | 25篇 |
1988年 | 22篇 |
1987年 | 12篇 |
1986年 | 11篇 |
1985年 | 8篇 |
1984年 | 16篇 |
1983年 | 14篇 |
1982年 | 12篇 |
1981年 | 11篇 |
1980年 | 7篇 |
1979年 | 2篇 |
1978年 | 3篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1975年 | 2篇 |
1973年 | 2篇 |
排序方式: 共有835条查询结果,搜索用时 0 毫秒
61.
JJ Korelitz ; AE Williams ; MP Busch ; TF Zuck ; HE Ownby ; LJ Matijas ; DJ Wright 《Transfusion》1994,34(10):870-876
BACKGROUND: Most blood centers utilize a confidential unit exclusion (CUE) process, intended to reduce the risk of transfusion-associated infectious diseases by allowing high-risk donors confidentially to exclude their blood from use for transfusion. The effectiveness of this method remains controversial. STUDY DESIGN AND METHODS: Confirmatory or supplemental test results for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus, as well as hepatitis B surface antigen and syphilis and screening test results for antibodies to hepatitis B core (antigen) and alanine aminotransferase levels were obtained for approximately 1.8 million units donated during 1991 and 1992 at five blood centers within the United States. The prevalences of these infectious disease markers in units that the donors confidentially excluded (CUE+) and units that the donors did not exclude (CUE-) were calculated and examined within demographic subgroups. RESULTS: Units that were CUE+ were 8 to 41 times more likely to be seropositive for antibodies to human immunodeficiency virus and hepatitis C virus, hepatitis B surface antigen, and syphilis and three to four times more likely to react for antibody to hepatitis B core (antigen) or to have elevated alanine aminotransferase levels than units that were CUE- (p < 0.001). The positive predictive value of CUE (the percentage of CUE+ units that were confirmed seropositive for any marker) was 3.5 percent, and the sensitivity of CUE (the percentage of confirmed-seropositive units that were CUE+) was 2.3 percent. CONCLUSION: The current CUE process has low sensitivity and apparently low positive predictive value, and in many cases, it appeared that donors misunderstood it. Yet, CUE was not a “random process,” as CUE+ units were more likely to be seropositive for any infectious disease marker than CUE- units. This suggests that efforts to improve the CUE system may be warranted. As risk factors for transfusion-transmitted infection become more difficult to identify by history-based screening, however, such efforts may have limited effect. 相似文献
62.
Development of the Manchester framework for the evaluation of emergency department pharmacy services
Greenwood D Tully MP Martin S Steinke D 《International journal of clinical pharmacy》2022,44(4):930-938
International Journal of Clinical Pharmacy - Many countries, including the United Kingdom, have established Emergency Department (ED) pharmacy services where some ED pharmacists now work as... 相似文献
63.
64.
65.
Hussein MA Sandstrom K Elson P Finke J McLain D Rayman P Rybicki LA Bukowski RA 《Journal of cancer research and clinical oncology》2001,127(10):619-624
PURPOSE: Some limitations of effective therapy in multiple myeloma include the low growth fraction of the malignant plasma cells, multi-drug resistance, and the presence of other concurrent diseases in this patient population. A phase I study was conducted to evaluate the toxicity of granulocyte macrophage colony stimulating factor (GM-CSF) in myeloma patients as well as the potential effect on the plasma cell labeling index (PCLI). Relapsed patients with multiple myeloma were eligible. METHODS: The first phase of this trial assessed the toxicity (including the effect on disease progression) of escalating doses (125-500 microg/m2 SC, days 1-5) of GM-CSF, and the effects of this cytokine on PCLI. Patients whose PCLI doubled and increased to > or = 1.7% were treated with chemotherapy including cyclophosphamide, vincristine, prednisone, and GM-CSF. Twenty-two patients were enrolled. RESULTS: The toxicity of GM-CSF was mild, and no dose-limiting side effects were seen. Twenty-five percent of patients (5/20) achieved the target PCLI, and 4/5 proceeded to receive chemotherapy. No relationship of GM-CSF dose to increases of the PCLI was noted. All patients who received chemotherapy responded. CONCLUSIONS: GM-CSF has acceptable toxicity in patients with multiple myeloma and produced increases of PCLI in selected individuals. Further studies of GM-CSF alone or in combination with chemotherapy are indicated. 相似文献
66.
MP Busch ; EA Operskalski ; JW Mosley ; CE Stevens ; ER Schiff ; SH Kleinman ; H Lee ; M Lee ; M Harris 《Transfusion》1994,34(10):858-864
BACKGROUND: The long-term course of human immunodeficiency virus type 1 (HIV-1)-related disease among seropositive blood donors has not been described. The enrollment and epidemiologic background of HIV-1- infected donors in the Transfusion Safety Study and their immunologic and clinical progression are described. STUDY DESIGN AND METHODS: Through the testing of approximately 200,000 sera from donations made in late 1984 and early 1985, 146 anti-HIV-1-positive donors and 151 uninfected matched donors were enrolled. These two cohorts were followed with 6-month interval histories and laboratory testing. RESULTS: Seropositive donors detected before the institution of routine anti-HIV-1 screening disproportionately were first-time donors and men with exclusively male sexual contacts. The actuarial probability of a person's developing AIDS within 7 years after donation was 40 percent; the probability of a person's dying of AIDS was 28 percent. AIDS developed more often when the donor was p24 antigen-positive at donation. Over a 3-year period, significant decreases occurred in CD4+, CD2+CD26+, CD4+CD29+, and CD20+CD21+ counts, but not in CD8+ subsets, CD20+, or CD14+. CONCLUSION: The high proportions of first-time donations and exclusively homosexual men among seropositive donors suggest that test-seeking may have contributed to the high HIV-1 prevalence in the repository. Implementation of alternative test sites when routine donor screening began in 1985 may have averted many high- risk donations. The disease course in HIV-1-infected donors had the same wide spectrum of immunologic and clinical manifestations as were reported for other cohorts. 相似文献
67.
TM Sankary ; G Yang ; JM Romeo ; PP Ulrich ; MP Busch ; BD Rawal ; GN Vyas 《Transfusion》1994,34(8):656-660
BACKGROUND: Since screening for antibody to hepatitis C virus (HCV) was introduced in 1990, posttransfusion hepatitis has been reduced to nearly background levels. This has led to reconsideration of the value of testing donated blood for elevated alanine aminotransferase (ALT). The contribution of ALT testing in detecting seronegative infection was evaluated by the performance of polymerase chain reaction (PCR) for hepatitis B virus (HBV) or HCV in plasma from ALT-elevated blood units. STUDY DESIGN AND METHODS: Testing was performed on 375 units of plasma, derived from an equivalent of 47,500 blood donations, with a highly sensitive hemi-nested PCR procedure. Using a triplet of primers directed at the conserved regions of HBV DNA and 5'-noncoding regions of HCV RNA, the hemi-nested PCR assay can reliably amplify 10 viral molecules to levels detectable in ethidium bromide-stained agarose gels. Pools of plasma from groups of four donors were screened with hemi-nested PCR. For any reactive pools, the plasma from individual donors was retested twice on different aliquots. RESULTS: Two of 375 units, both with midrange ALT elevation, were repeatedly reactive in hemi-nested PCR (one each for HBV DNA and HCV RNA). However, samples from the two suspect donors tested 9 and 5 months later revealed no seroconversion, elevated ALT, or viral genomes in hemi-nested PCR. CONCLUSION: The lack of confirmed HBV or HCV infection in this study representing an estimated 47,500 voluntary blood donations suggests that routine ALT testing for further prevention of posttransfusion hepatitis after exclusion of HBV- and/or HCV-seropositive blood may be superfluous. 相似文献
68.
Maat M Buysse CM Emonts M Spanjaard L Joosten KF de Groot R Hazelzet JA 《Critical care (London, England)》2007,11(5):R112
Background
To gain insight into factors that might affect results of future case-control studies, we performed an analysis of children with sepsis and purpura admitted to the paediatric intensive care unit (PICU) of Erasmus MC-Sophia Children's Hospital (Rotterdam, The Netherlands). 相似文献69.
Shenaz Ramtoola Edward Jude Anthony Robinson Iqbal Malik Gerrard Rayman Cuong Dang Graham David Ross Martin Amar Ali 《Journal of diabetes science and technology》2014,8(4):776-782
Background:Accurate calculation and adjustment of insulin doses is integral to maintaining glycemic control in insulin treated patients. Difficulties with insulin dose calculations may lead to poor adherence to blood glucose monitoring and insulin treatment regimes, resulting in poor metabolic control. The main objective of this study was to evaluate ease of use and user preference of a high specification touch screen blood glucose meter, which has an in-built insulin calculator, compared to patients’ usual method of testing blood glucose and deciding insulin doses.Methods:Patients with diabetes on a multiple daily injection insulin regime used the Test Meter without the insulin calculator and 1 of 3 comparator meters, each for a 7-day period. They then used the Test Meter with the in-built calculator for 10 days. Patients completed an ease of use questionnaire after each 7-day period, a preference questionnaire after the second 7-day period, and a questionnaire comparing the Test Meter with their usual method after the final 10-day period.Results:Of 164 patients who completed the study, 76% stated a preference for the Test Meter as a diabetes management tool compared to their usual method. A small number of patients preferred familiar methods and/or calculating insulin doses themselves. The log book function of meters was important to most patients.Conclusions:The Test Meter system with in-built insulin calculator supports people to better manage their diabetes and increases their confidence. Patients have different needs and preferences which should be acknowledged and supported in a patient centered health service. 相似文献
70.
Mepacrine uptake into platelets and bone marrow megakaryocytes was analyzed to further characterize the dense granule defects in a group of seven mouse pigment mutants that have characteristics of platelet storage pool disease (SPD). In contrast to our previous studies using electron microscopy, this method revealed that all mutants had normal numbers of dense granules. However, total mepacrine uptake in all mutant platelets was significantly diminished to less than 50% of normal uptake. Also, the flashing phenomenon observed when normal dense granules are irradiated with ultraviolet light was either greatly diminished or absent when platelets of individual mutants were similarly irradiated. Therefore the principal defect in the mutant platelets is an inability to accumulate dense granule contents rather than an absence of the granules. Mepacrine uptake into megakaryocytes was indistinguishable in normal and mutant mice. This indicates the mutant dense granule defects appear either very late in megakaryocyte development or early in platelet formation in correlation with development of the mature dense granule. By standard transmission electron microscopy we have not been able to detect gross structural or subcellular abnormalities in either platelets or megakaryocytes of mutant mice. It appears all seven mutants produce immature or functionally abnormal dense granules. 相似文献