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51.
A. Keshavarzian MD F. L. Iber MD P. Greer RT J. Wobbteton RNNP 《Alcoholism, clinical and experimental research》1986,10(4):432-435
Nausea and vomiting are common complaints in chronic alcoholics. Autonomic neuropathy and esophageal motor abnormalities are frequently observed in chronic alcoholics, but gastric emptying has not been studied in these patients. Gastric emptying of a solid meal was measured, using 99mTc-sulfur colloid cooked in a scrambled egg, in 10 male chronic alcoholics with upper gastrointestinal complaints of nausea and vomiting. All patients were adequately nourished, recently drinking, but just over withdrawal and free of clinical peripheral neuropathy. Gastric emptying in 10 alcoholics was similar to 5 normal controls (t 1/2 115 +/- 12 versus 107 +/- 8 min). These data suggest that upper gastrointestinal symptoms in chronic alcoholics are not related to gastric motor dysfunction. 相似文献
52.
A nomenclature for tests of thyroid hormones in serum: report of a committee of the American Thyroid Association 总被引:4,自引:0,他引:4
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Calpains promote neutrophil recruitment and bacterial clearance in an acute bacterial peritonitis model 下载免费PDF全文
Vijay Kumar Stephanie Everingham Christine Hall Peter A. Greer Andrew W. B. Craig 《European journal of immunology》2014,44(3):831-841
Activation of the innate immune system is critical for clearance of bacterial pathogens to limit systemic infections and host tissue damage. Here, we report a key role for calpain proteases in bacterial clearance in mice with acute peritonitis. Using transgenic mice expressing Cre recombinase primarily in innate immune cells (fes‐Cre), we generated conditional capns1 knockout mice. Consistent with capns1 being essential for stability and function of the ubiquitous calpains (calpain‐1, calpain‐2), peritoneal cells from these mice had reduced levels of calpain‐2/capns1, and reduced proteolysis of their substrate selenoprotein K. Using an acute bacterial peritonitis model, we observed impaired bacterial killing within the peritoneum and development of bacteremia in calpain knockout mice. These defects correlated with significant reductions in IL‐1α release, neutrophil recruitment, and generation of reactive oxygen species in calpain knockout mice with acute bacterial peritonitis. Peritoneal macrophages from calpain knockout mice infected with enterobacteria ex vivo, were competent in phagocytosis of bacteria, but showed impaired clearance of intracellular bacteria compared with control macrophages. Together, these results implicate calpains as key mediators of effective innate immune responses to acute bacterial infections, to prevent systemic dissemination of bacteria that can lead to sepsis. 相似文献
55.
Simin Lu Kohsuke Kanekura Takashi Hara Jana Mahadevan Larry D. Spears Christine M. Oslowski Rita Martinez Mayu Yamazaki-Inoue Masashi Toyoda Amber Neilson Patrick Blanner Cris M. Brown Clay F. Semenkovich Bess A. Marshall Tamara Hershey Akihiro Umezawa Peter A. Greer Fumihiko Urano 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(49):E5292-E5301
Wolfram syndrome is a genetic disorder characterized by diabetes and neurodegeneration and considered as an endoplasmic reticulum (ER) disease. Despite the underlying importance of ER dysfunction in Wolfram syndrome and the identification of two causative genes, Wolfram syndrome 1 (WFS1) and Wolfram syndrome 2 (WFS2), a molecular mechanism linking the ER to death of neurons and β cells has not been elucidated. Here we implicate calpain 2 in the mechanism of cell death in Wolfram syndrome. Calpain 2 is negatively regulated by WFS2, and elevated activation of calpain 2 by WFS2-knockdown correlates with cell death. Calpain activation is also induced by high cytosolic calcium mediated by the loss of function of WFS1. Calpain hyperactivation is observed in the WFS1 knockout mouse as well as in neural progenitor cells derived from induced pluripotent stem (iPS) cells of Wolfram syndrome patients. A small-scale small-molecule screen targeting ER calcium homeostasis reveals that dantrolene can prevent cell death in neural progenitor cells derived from Wolfram syndrome iPS cells. Our results demonstrate that calpain and the pathway leading its activation provides potential therapeutic targets for Wolfram syndrome and other ER diseases.The endoplasmic reticulum (ER) takes center stage for protein production, redox regulation, calcium homeostasis, and cell death (1, 2). It follows that genetic or acquired ER dysfunction can trigger a variety of common diseases, including neurodegenerative diseases, metabolic disorders, and inflammatory bowel disease (3, 4). Breakdown in ER function is also associated with genetic disorders such as Wolfram syndrome (5–8). It is challenging to determine the exact effects of ER dysfunction on the fate of affected cells in common diseases with polygenic and multifactorial etiologies. In contrast, we reasoned that it should be possible to define the role of ER dysfunction in mechanistically homogenous patient populations, especially in rare diseases with a monogenic basis, such as Wolfram syndrome (9).Wolfram syndrome (OMIM 222300) is a rare autosomal recessive disorder characterized by juvenile-onset diabetes mellitus and bilateral optic atrophy (7). Insulin-dependent diabetes usually occurs as the initial manifestation during the first decade of life, whereas the diagnosis of Wolfram syndrome is invariably later, with onset of symptoms in the second and ensuing decades (7, 10, 11). Two causative genes for this genetic disorder have been identified and named Wolfram syndrome 1 (WFS1) and Wolfram syndrome 2 (WFS2) (12, 13). It has been shown that multiple mutations in the WFS1 gene, as well as a specific mutation in the WFS2 gene, lead to β cell death and neurodegeneration through ER and mitochondrial dysfunction (5, 6, 14–16). WFS1 gene variants are also associated with a risk of type 2 diabetes (17). Moreover, a specific WFS1 variant can cause autosomal dominant diabetes (18), raising the possibility that this rare disorder is relevant to common molecular mechanisms altered in diabetes and other human chronic diseases in which ER dysfunction is involved.Despite the underlying importance of ER malfunction in Wolfram syndrome, and the identification of WFS1 and WFS2 genes, a molecular mechanism linking the ER to death of neurons and β cells has not been elucidated. Here we show that the calpain protease provides a mechanistic link between the ER and death of neurons and β cells in Wolfram syndrome. 相似文献
56.
Identifying the appropriate wheelchair for a person who needs one has implications for both disabled persons and society. For someone with severe locomotive problems, the right wheelchair can affect mobility and quality of life. However, policymakers are concerned about the increasing demand for unnecessarily elaborate chairs. The Office of Inspector General, U.S. Department of Health and Human Services, issued 4 reports between 2009 and 2011 detailing fraud and misapplication of Medicare funds for powered wheelchairs, more than a decade after similar concerns were first raised by 4 contractors who process claims for durable medical equipment. Subsequent concerns have arisen about whether some impaired persons who need wheeled mobility devices may now be inappropriately denied coverage. A transparent, evidence-based approach to wheeled mobility service delivery (the matching of mobility-impaired persons to appropriate devices and supporting services) might lessen these concerns. This review describes the process of wheeled mobility service delivery for long-term wheelchair users with complex rehabilitation needs and presents findings from a survey of the literature (published and gray) and interviews with key informants. Recommended steps in the delivery process were identified in textbooks, guidelines, and published literature. Delivery processes shared many commonalities; however, no research supports the recommended approaches. A search of bibliographic databases through March 2011 identified 24 studies that evaluated aspects of wheeled mobility service delivery. Most were observational, exploratory studies designed to determine consumer use of and satisfaction with the process. The evidence base for the effectiveness of approaches to wheeled mobility service delivery is insufficient, and additional research is needed to develop standards and guidelines. 相似文献
57.
58.
Feasibility of using multivector impedance to monitor pulmonary congestion in heart failure patients
Philip F. Binkley James G. Porterfield Linda M. Porterfield Scott L. Beau Raffaele Corbisiero G. Stephen Greer Charles J. Love Melanie Turkel Anders Bjorling Fujian Qu Taraneh G. Farazi 《Journal of interventional cardiac electrophysiology》2012,35(2):197-206
Purpose
Pulmonary edema (PE) is associated with fluid accumulation in the lungs. Device-based impedance measurements have been used to detect fluid overload prior to hospitalization. However, studies have reported a high false positive rate (FPR). The objective of this study was to develop and test a new multivector impedance-based algorithm that reliably tracks PE clinical events.Methods
We enrolled patients with implanted CRT-Ds in 23 US centers within 2 weeks of device implant. Six-vector impedance data was collected automatically by the CRT-Ds every 30 min during emergency department visits/hospitalizations and every 2 h at all other times. Detection algorithms for cardiac resynchronization therapy defibrillator (CRT-D) and implantable cardiac defibrillator (ICD) devices were developed using those impedance vectors that would be available in corresponding devices and retrospectively evaluated.Results
There were 75 patients (69 % male), mean age 66?±?12 years, with a LVEF of 23?±?6 % and QRS of 149?±?25 ms. Twenty-one major clinical events occurred over 8.2?±?2.6 months of follow-up time. CRT-D vector combinations resulted in a sensitivity of 71.4 % (95 % confidence interval 47.8–88.7) and a FPR of 0.56 (0.30–0.94) false positives per patient-year (FPs/pt-yr); ICD vector combinations resulted in a sensitivity of 61.9 % (38.4–81.9) and a FPR of 0.63 (0.36–0.90) FPs/pt-yr. In comparison, the single-vector RVCoil-Can implementation of this algorithm resulted in a sensitivity of 57.1 % (34.0–78.2) and a FPR of 0.74 (0.44–1.12) FPs/pt-yr.Conclusions
This multivector impedance algorithm was effective in tracking PE clinical events in this patient population. Additional studies are needed to prospectively evaluate the performance of this algorithm in a larger population. 相似文献59.
60.
Anna E. Greer Stacey Davis Cristina Sandolo Nicole Gaudet Brianna Castrogivanni 《Journal of nutrition education and behavior》2018,50(2):133-140.e1