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排序方式: 共有2725条查询结果,搜索用时 15 毫秒
61.
Dallo FJ Weller SC 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(18):10574-10579
Screening guidelines proposed by the Expert Committee on the Diagnosis and Classification of Diabetes Mellitus have been endorsed by several medical societies. However, one-third of cases are undiagnosed, and complications at the time of diagnosis indicate that disease may have been present for several years before diagnosis. This study evaluates the effectiveness of the guidelines for detecting new cases of diabetes mellitus. By using a cross-sectional, representative sample of the United States (National Health and Nutritional Examination Survey, NHANES III), the guidelines are tested on adults, 20 years and older without a prior diagnosis of diabetes. Individuals are classified as nondiabetics (n = 6,241) or as having undiagnosed diabetes (n = 274) based on their blood glucose. Screening when one risk factor is present, as stated in the guidelines, has a true-positive rate of 100% and would require that 83% of the population be tested. Screening when two risk factors are present is more efficient, with a comparable true-positive rate (98%), but requires that only 59% of the population be tested. A notable finding is the earlier age of onset among minorities, which may be associated with other health disparities. Because diabetes occurs at younger ages in minorities, screening whites who are > or =40 and minorities > or =30 years of age has a high true-positive rate (95%) and also reduces testing (60%). The screening guidelines would be effective, if followed, and would essentially eliminate undiagnosed cases of diabetes. 相似文献
62.
Roy O. Weller Cheryl A. Hawkes Raj N. Kalaria David J. Werring Roxana O. Carare 《Brain pathology (Zurich, Switzerland)》2015,25(1):63-78
White matter abnormalities on magnetic resonance imaging (MRI) are associated with dementia and include white matter hyperintensities (WMH; also termed leukoaraiosis) and visible perivascular spaces (PVS). We review the potential role of impaired drainage of interstitial fluid in the pathogenesis of WMH and PVS. Whereas the volume of extracellular space in the grey matter is tightly controlled, fluid accumulates and expands the extracellular spaces of the white matter in acute hydrocephalus, vasogenic edema and WMH. Although there are no conventional lymphatic vessels in the brain, there is very effective lymphatic drainage for fluid and solutes along restricted pathways in the basement membranes of cerebral capillaries and arteries in young individuals. Lymphatic drainage of the brain is impaired with age and in association with apolipoprotein E ε4, risk factors for Alzheimer's disease and cerebral amyloid angiopathy (CAA). Deposition of proteins in the lymphatic drainage pathways in the walls of cerebral arteries with age is recognized as protein elimination failure angiopathy (PEFA), as in CAA and cerebral autosomal dominant arteriopathy and leukoencephalopathy (CADASIL). Facilitating perivascular lymphatic drainage from the aging brain may play a significant role in the prevention of CAA, WMH and Alzheimer's disease and may enhance the efficacy of immunotherapy for Alzheimer's disease. 相似文献
63.
2-Methoxyestradiol overcomes drug resistance in multiple myeloma cells 总被引:13,自引:11,他引:13
Chauhan D Catley L Hideshima T Li G Leblanc R Gupta D Sattler M Richardson P Schlossman RL Podar K Weller E Munshi N Anderson KC 《Blood》2002,100(6):2187-2194
2-Methoxyestradiol (2ME2) an estrogen derivative, induces growth arrest and apoptosis in leukemic cells and is also antiangiogenic. In this study, we demonstrate that 2ME2 inhibits growth and induces apoptosis in multiple myeloma (MM) cell lines and patient cells. Significantly, 2ME2 also inhibits growth and induces apoptosis in MM cells resistant to conventional therapies including melphalan (LR-5), doxorubicin (Dox-40 and Dox-6), and dexamethasone (MM.1R). In contrast to its effects on MM cells, 2ME2 does not reduce the survival of normal peripheral blood lymphocytes. Moreover, 2ME2 enhances Dex-induced apoptosis, and its effect is not blocked by interleukin-6 (IL-6). We next examined the effect of 2ME2 on MM cells in the bone marrow (BM) milieu. 2ME2 decreases survival of BM stromal cells (BMSCs), as well as secretion of vascular endothelial growth factor (VEGF), and IL-6 triggered by the adhesion of MM cells to BMSCs. We show that apoptosis induced by 2ME2 is mediated by the release of mitochondrial cytochrome-c (cyto-c) and Smac, followed by the activation of caspases-8, -9, and -3. Finally, 2ME2 inhibits MM cell growth, prolongs survival, and decreases angiogenesis in a murine model. These studies, therefore, demonstrate that 2ME2 mediates anti-MM activity directly on MM cells and in the BM microenvironment. They provide a framework for the use of 2ME2, either alone or in combination with Dex, to overcome drug resistance and to improve outcome in MM. 相似文献
64.
Clinical, biochemical, serological, histological and ultrastructural features of liver disease in drug abusers 下载免费PDF全文
I V Weller D Cohn A Sierralta M Mitcheson M G Ross L Montano P Scheuer H C Thomas 《Gut》1984,25(4):417-423
Heroin abusers are frequently found to have abnormal liver function tests and hepatic histology. Hepatitis viruses A, B, and NANB, other drugs or drug contaminants and excessive alcohol consumption are factors thought to contribute. One hundred and sixteen heroin abusers attending a London treatment centre were studied. Sixty two (53%) had a raised aspartate transaminase. This was not explained by current infection with hepatitis A and B, cytomegalo or Epstein-Barr viruses, excessive alcohol consumption (greater than 80 g/day) or concomitant drug taking. Abnormal liver function tests were as frequent in those with markers of current or past HBV infection as those without and there was evidence that both HBV infection and the cause of the abnormal liver function tests were acquired in the first few years of intravenous drug abuse. Liver biopsies from eight patients showed chronic hepatitis with a mild lobular and portal inflammatory infiltrate, fatty change and prominent sinusoidal cells. Electron microscopy showed cytoplasmic trilaminar tubular structures and dense fused membranes in dilated endoplasmic reticulum. These clinical, biochemical, serological, and histological features would suggest a major role for NANB virus infection in the aetiology of hepatitis in heroin abusers. 相似文献
65.
Lefkowitz JB DeBoom T Weller A Clarke S Lavrinets D 《American journal of hematology》2000,63(3):149-155
A new fibrinogen variant was discovered as a result of discrepancies found in routine laboratory screening. The patient, a healthy 37-year-old woman, had a mild bleeding history. Initial coagulation studies on the patient revealed a prolonged prothrombin time (PT) and a normal activated partial thromboplastin time (APTT). Further investigation on the patient and her mother demonstrated both had a PT with no end point using an optical detection method (ACL3000+) and a normal PT using an electromechanical detection method (ST4 Clot Detection System). The APTT for both the patient and her mother were essentially normal with both optical and mechanical detection methods. The patient and her mother also had markedly prolonged thrombin time and reptilase time results on the ACL3000+, but they were normal on the ST4. Coagulation test results on the patient's father were all normal. We believe the fibrinogen defect in this family may affect fibrin polymerization only enough to effect light scatter interpretation, while there is enough polymerization to increase plasma viscosity and yield an end point using an electromechanical analyzer. This report should alert pathologists and clinicians to possible discrepancies between mechanical and spectrophotometric clot testing methods. 相似文献
66.
67.
Stoecklein Veit Michael Kellert Lars Patzig Maximilian Küpper Clemens Giese Armin Ruf Viktoria Weller Jonathan Kreth Friedrich-Wilhelm Schöberl Florian 《Journal of neurology》2021,268(1):367-376
Journal of Neurology - To evaluate the diagnostic accuracy and safety of extended stereotactic brain biopsy (ESBB) in a single center cohort with suspected primary angiitis of the central nervous... 相似文献
68.
Two patients had gangrenous dermal necrosis associated with chronic renal disease and secondary hyperparathyroidism. Thromobosed and heavily calcified small arteries were underlying the infarcted areas. One patient had severe hypotension secondary to hemorrhage, which immediately preceded the appearance of dermal lesions. Both patients had notably elevated serum parathyroid hormone and serum alkaline phosphatase levels, as well as severe hyperphosphatemia. Therapy with phosphate binders and calcium and vitamin D supplementation corrected the hyperphosphatemia and reduced serum alkaline phosphatase levels. One patient died; the other patient's dermal lesions healed completely. Localized thrombosis, rather than obliterative intimal proliferation, represents a unique cause of dermal necrosis in this condition. 相似文献
69.
Smadar Nahaliel Eliane Sommerfeld Israel Orbach Aron Weller Alan Apter Gil Zalsman 《Comprehensive psychiatry》2014
Background
This study used path-analysis to examine the assumption that the presence of mental pain in adults mediates the relationship between self-destruction, number of losses experienced in one’s life, and suicidal tendency.Methods
Fifty suicidal inpatients, 50 non-suicidal inpatients and 50 healthy volunteers were assessed for self-destruction, losses experienced, depression, suicidal tendency, and mental pain.Results
Self-destruction was found to have both a direct effect on suicidal tendency as well as one mediated by the presence of mental pain. Number of losses effected suicidal tendency only indirectly, mediated by the presence of mental pain. Overall, self-destruction was a more significant determinant of suicidal tendency than were the number of losses experienced during one’s life. A competing model, with depression replacing mental pain as the mediator, was also found to fit the data.Discussion
These findings provide evidence that the presence of mental pain is a mediator in the relationships between both self-destruction and number of losses experienced, and between suicidal tendencies. More studies are needed in order to further differentiate between mental pain and depression as mediators in suicidal tendency. 相似文献70.
Lacee J. Laufenberg Gregory E. Weller Charles H. Lang Victor Ruiz-Velasco 《The Journal of surgical research》2013