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991.
992.
993.
Use of paper-absorbed fingerstick blood samples for studies of antibody to human immunodeficiency virus type 1 in intravenous drug users 总被引:1,自引:0,他引:1
K A Steger D E Craven B F Shea B R Fitzgerald M Schwerzler R Seage GR d Hoff 《The Journal of infectious diseases》1990,162(4):964-967
The suitability of paper-absorbed (PA) fingerstick blood specimens for antibody testing of human immunodeficiency virus type 1 (HIV-1) was examined in two populations of intravenous drug users (IVDU): 393 persons from a drop-in counseling and testing clinic and 145 from a methadone treatment clinic. From the first group, the same 66 immunoblot-confirmed enzyme immunoassay (EIA)-positive specimens were identified in sera from venipuncture and parallel fingerstick PA specimens. The latter had slightly higher EIA mean background levels resulting in 10 immunoblot-negative EIA-positive samples versus 6 in the sera group. HIV-1 seroprevalence was 17% of 393 from the drop-in clinic. By category of IVDU, the rates were 34% and 14% for active and recovering IVDU, respectively (P less than .001), and 36% in black and Latino compared with 13% in white IVDU (P less than .002). Of the 145 participants in the methadone program, 39% had antibody to HIV-1: 49% for blacks and Latinos compared with 30% in whites (P less than .01). The data indicate that antibody testing for HIV-1 by PA is equivalent to the serum antibody assay of venipuncture specimens. The fingerstick method appears to have greater use for serosurveys and screening programs because of convenience, safety, and ease of storage, transport, and processing of samples. 相似文献
994.
The enhancement of in vitro human hematopoiesis by the addition of a noncytotoxic monoclonal antibody, 9.1C3, is described. Enhancement of all aspects of in vitro hematopoiesis was observed on addition of 9.1C3 antibody to cultures of mononuclear cells from normal bone marrow, cord blood, and peripheral blood from beta-thalassemia major patients. In cultures with no exogenous colony-stimulating factor (CSF), the addition of 9.1C3 resulted in a two- to eightfold increase in nonerythroid colony formation. Similarly, for cultures maximally stimulated with CSF, the addition of 9.1C3 antibody resulted in a one- to fourfold increase in colony formation. These effects were abrogated by the removal of either adherent, Leu-M3+ or Leu-7+ cells. Colony- forming cells were shown to be present among the 9.1C3-negative cells when mononuclear cells were sorted by flow cytometry. Media conditioned in the presence of 9.1C3 and mononuclear cells were able to enhance colony formation in vitro for normal nonadherent bone marrow cells beyond that achieved with supramaximal amounts of human placental- conditioned medium and erythropoietin. The data suggest that natural killer cells interact with monocytes to exert a negative regulatory control on in vitro granulopoiesis and erythropoiesis. Consequently, the number of progenitor and multipotential cells in cultures of unfractionated cell populations may be greatly underestimated. 相似文献
995.
Pharmacovigilance (PV) plays a key role in the healthcare system through
assessment, monitoring and discovery of interactions amongst drugs and their
effects in human. Pharmaceutical and biotechnological medicines are designed to
cure, prevent or treat diseases; however, there are also risks particularly
adverse drug reactions (ADRs) can cause serious harm to patients. Thus, for
safety medication ADRs monitoring required for each medicine throughout its life
cycle, during development of drug such as pre-marketing including early stages
of drug design, clinical trials, and post-marketing surveillance. PV is concerns
with the detection, assessment, understanding and prevention of ADRs.
Pharmacogenetics and pharmacogenomics are an indispensable part of the clinical
research. Variation in the human genome is a cause of variable response to drugs
and susceptibility to diseases are determined, which is important for early drug
discovery to PV. Moreover, PV has traditionally involved in mining spontaneous
reports submitted to national surveillance systems. The research focus is
shifting toward the use of data generated from platforms outside the
conventional framework such as electronic medical records, biomedical
literature, and patient-reported data in health forums. The emerging trend in PV
is to link premarketing data with human safety information observed in the
post-marketing phase. The PV system team obtains valuable additional
information, building up the scientific data contained in the original report
and making it more informative. This necessitates an utmost requirement for
effective regulations of the drug approval process and conscious pre and post
approval vigilance of the undesired effects, especially in India. Adverse events
reported by PV system potentially benefit to the community due to their
proximity to both population and public health practitioners, in terms of
language and knowledge, enables easy contact with reporters by electronically.
Hence, PV helps to the patients get well and to manage optimally or ideally,
avoid illness is a collective responsibility of industry, drug regulators,
clinicians and other healthcare professionals to enhance their contribution to
public health. This review summarized objectives and methodologies used in PV
with critical overview of existing PV in India, challenges to overcome and
future prospects with respect to Indian context. 相似文献
996.
Harsh Panwar Danielle Calderwood Irene R. Grant Sunita Grover Brian D. Green 《European journal of nutrition》2014,53(7):1465-1474
Purpose
Inhibitors of intestinal alpha-glucosidases are used therapeutically to treat type 2 diabetes mellitus. Bacteria such as Actinoplanes sp. naturally produce potent alpha-glucosidase inhibitor compounds, including the most widely available drug acarbose. It is not known whether lactic acid bacteria (LAB) colonising the human gut possess inhibitory potential against glucosidases. Hence, the study was undertaken to screen LABs having inherent alpha- and beta-glucosidase inhibitory potential.Methods
This study isolated, screened, identified and extracted Lactobacillus strains (Lb1–15) from human infant faecal samples determining their inhibitory activity against intestinal maltase, sucrase, lactase and amylase. Lactobacillus reference strains (Ref1–7), a Gram positive control (Ctrl1) and two Gram negative controls (Ctrl2–3), were also analysed to compare activity.Results
Faecal isolates were identified by DNA sequencing, with the majority identified as unique strains of Lactobacillus plantarum. Some strains (L. plantarum, L. fermentum, L. casei and L. rhamnosus) had potent and broad spectrum inhibitory activities (up to 89 %; p < 0.001; 500 mg/ml wet weight) comparable to acarbose (up to 88 %; p < 0.001; 30 mg/ml). Inhibitory activity was concentration-dependent and was freely available in the supernatant, and was not present in other bacterial genera (Bifidobacterium bifidum and Escherichia coli or Salmonella typhimurium). Interestingly, the potency and spectrum of inhibitory activity across strains of a single species (L. plantarum) differed substantially. Some Lactobacillus extracts had broader spectrum activities than acarbose, effectively inhibiting beta-glucosidase activity (lactase) as well as alpha-glucosidase activities (maltase, sucrase and amylase). Anti-diabetic potential was indicated by the fact that oral gavage with a L. rhamnosus extract (1 g/kg) was able to reduce glucose excursions (Area under curve; 22 %; p < 0.05) in rats during a carbohydrate challenge (starch; 2 g/kg).Conclusion
These results definitively demonstrate that Lactobacillus strains present in the human gut have alpha- and beta-glucosidase inhibitory activities and can reduce blood glucose responses in vivo. Although the potential use of LAB such as Lactobacillus as a dietary supplement, medicinal food or biotherapeutic for diabetes is uncertain, such an approach might offer advantages over drug therapies in terms of broader spectrum activities and fewer unpleasant side effects. Further characterisation of this bioactivity is warranted, and chronic studies should be undertaken in appropriate animal models or diabetic subjects. 相似文献997.
Harsh Chauhan Anuj Kuldipkumar Timothy Barder Ales Medek Chong-Hui Gu Eman Atef 《Pharmaceutical research》2014,31(2):500-515
Purpose
To correlate the polymer’s degree of precipitation inhibition of indomethacin in solution to the amorphous stabilization in solid state.Methods
Precipitation of indomethacin (IMC) in presence of polymers was continuously monitored by a UV spectrophotometer. Precipitates were characterized by PXRD, IR and SEM. Solid dispersions with different polymer to drug ratios were prepared using solvent evaporation. Crystallization of the solid dispersion was monitored using PXRD. Modulated differential scanning calorimetry (MDSC), IR, Raman and solid state NMR were used to explore the possible interactions between IMC and polymers.Results
PVP K90, HPMC and Eudragit E100 showed precipitation inhibitory effects in solution whereas Eudragit L100, Eudragit S100 and PEG 8000 showed no effect on IMC precipitation. The rank order of precipitation inhibitory effect on IMC was found to be PVP K90?>?Eudragit E100?>?HPMC. In the solid state, polymers showing precipitation inhibitory effect also exhibited amorphous stabilization of IMC with the same rank order of effectiveness. IR, Raman and solid state NMR studies showed that rank order of crystallization inhibition correlates with strength of molecular interaction between IMC and polymers.Conclusions
Correlation is observed in the polymers ability to inhibit precipitation in solution and amorphous stabilization in the solid state for IMC and can be explained by the strength of drug polymer interactions. 相似文献998.
Harsh Sancheti Ishan Patil Keiko Kanamori Roberta Díaz Brinton Wei Zhang Ai-Ling Lin Enrique Cadenas 《Journal of cerebral blood flow and metabolism》2014,34(11):1749-1760
Alzheimer''s disease (AD) is characterized by age-dependent biochemical, metabolic, and physiologic changes. These age-dependent changes ultimately converge to impair cognitive functions. This study was carried out to examine the metabolic changes by probing glucose and tricarboxylic acid cycle metabolism in a 7-month-old triple transgenic mouse model of AD (3xTg-AD). The effect of lipoic acid, an insulin-mimetic agent, was also investigated to examine its ability in modulating age-dependent metabolic changes. Seven-month-old 3xTg-AD mice were given intravenous infusion of [1-13C]glucose followed by an ex vivo
13C nuclear magnetic resonance to determine the concentrations of 13C-labeled isotopomers of glutamate, glutamine, aspartate, gamma aminobutyric acid, and N-acetylaspartate. An intravenous infusion of [1-13C]glucose+[1,2-13C]acetate was given for different periods of time to distinguish neuronal and astrocytic metabolism. Enrichments of glutamate, glutamine, and aspartate were calculated after quantifying the total (12C+13C) concentrations by high-performance liquid chromatography. A hypermetabolic state was clearly evident in 7-month-old 3xTg-AD mice in contrast to the hypometabolic state reported earlier in 13-month-old mice. Hypermetabolism was evidenced by prominent increase of 13C labeling and enrichment in the 3xTg-AD mice. Lipoic acid feeding to the hypermetabolic 3xTg-AD mice brought the metabolic parameters to the levels of nonTg mice. 相似文献
999.
Sensitivity of brachial versus femoral vein injection of agitated saline to detect right‐to‐left shunts with Transcranial Doppler
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1000.
Martin A. Alpert Harsh Agrawal Kul Aggarwal Senthil A. Kumar Arun Kumar 《Current heart failure reports》2014,11(2):156-165
Obesity is both a risk factor and a direct cause of heart failure (HF) in adults. Severe obesity produces hemodynamic alterations that predispose to changes in left ventricular morphology and function, which, over time, may lend to the development of HF (obesity cardiomyopathy). Certain neurohormonal and metabolic abnormalities as well as cardiovascular co-morbidities may facilitate this process. Substantial purposeful weight loss is capable of reversing most of the alterations in cardiac performance and morphology and may improve functional capacity and quality of life in patents with obesity cardiomyopathy. 相似文献