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81.
Meites E Jay MT Deresinski S Shieh WJ Zaki SR Tompkins L Smith DS 《Emerging infectious diseases》2004,10(3):406-412
Leptospirosis is a reemerging infectious disease in California. Leptospirosis is the most widespread zoonosis throughout the world, though it is infrequently diagnosed in the continental United States. From 1982 to 2001, most reported California cases occurred in previously healthy young adult white men after recreational exposures to contaminated freshwater. We report five recent cases of human leptospirosis acquired in California, including the first documented common-source outbreak of human leptospirosis acquired in this state, and describe the subsequent environmental investigation. Salient features in the California cases include high fever with uniform renal impairment and mild hepatitis. Because leptospirosis can progress rapidly if untreated, this reemerging infection deserves consideration in febrile patients with a history of recreational freshwater exposure, even in states with a low reported incidence of infection. 相似文献
82.
Cheng SY Lee WC Shieh LW Chen JC 《Archives of environmental contamination and toxicology》2004,47(3):352-362
Marsupenaeus japonicus (6.37 ± 1.29 g) individually exposed to 9 different combined solutions of ambient ammonia (C) and nitrite (C) ammonia at 0.003 [control], 0.39, and 1.49 mmol/L combined with nitrite at 0.001 [control], 0.38, and 1.49 mmol/L in 30 ppt were examined for nitrogenous excretion accumulations of ammonia, nitrite, urea, and uric acid in tissues after 48 hours. M. japonicus exposed to 0.39 mmol/L ammonia–0.38 mmol/L nitrite displayed higher levels of urea-nitrogen (UNE) and organic-N (ONE) excretion by a factor of 2.2 and 5.7, respectively, compared with shrimp exposed only to 0.39 mmol/L ammonia. Exposure to 0.39 mmol/L ammonia–0.38 mmol/L nitrite resulted in lower levels of hemolymph uric acid (HUA), gill ammonia (GAM), gill urea (GUE), gill uric acid (GUA), hepatopancreas ammonia (HPAM), hepatopancreas urea (HPUE), and hepatopancreas uric acid (APUA), respectively, compared with shrimp exposed only to 0.39 mmol/L ammonia. We concluded that M. japonicus exposed to combined environments of ammonia and nitrite display increased nitrogen metabolism and production of urea-N and other organic-N. 相似文献
83.
In vitro and in vivo characterization of a novel naphthylamide ATP-sensitive K+ channel opener, A-151892 总被引:1,自引:0,他引:1 下载免费PDF全文
Gopalakrishnan M Buckner SA Shieh CC Fey T Fabiyi A Whiteaker KL Davis-Taber R Milicic I Daza AV Scott VE Castle NA Printzenhoff D London B Turner SC Carroll WA Sullivan JP Coghlan MJ Brune ME 《British journal of pharmacology》2004,143(1):81-90
1. Openers of ATP-sensitive K(+) channels are of interest in several therapeutic indications including overactive bladder and other lower urinary tract disorders. This study reports on the in vitro and in vivo characterization of a structurally novel naphthylamide N-[2-(2,2,2-trifluoro-1-hydroxy-1-trifluoromethyl-ethyl)-naphthalen-1-yl]-acetamide (A-151892), as an opener of the ATP-sensitive potassium channels. 2. A-151892 was found to be a potent and efficacious potassium channel opener (KCO) as assessed by glibenclamide-sensitive whole-cell current and fluorescence-based membrane potential responses (-log EC(50)=7.63) in guinea-pig bladder smooth muscle cells. 3. Evidence for direct interaction with KCO binding sites was derived from displacement of binding of the 1,4-dihydropyridine opener [(125)I]A-312110. A-151892 displaced [(125)I]A-312110 binding to bladder membranes with a -log Ki value of 7.45, but lacked affinity against over 70 neurotransmitter receptor and ion channel binding sites. 4. In pig bladder strips, A-151892 suppressed phasic, carbachol-evoked and electrical field stimulus-evoked contractility in a glibenclamide-reversible manner with -log IC(50) values of 8.07, 7.33 and 7.02 respectively, comparable to that of the potencies of the prototypical cyanoguanidine KCO, P1075. The potencies to suppress contractions in thoracic aorta (-log IC(50)=7.81) and portal vein (-log IC(50)=7.98) were not substantially different from those observed for suppression of phasic contractility of the bladder smooth muscle. 5. In vivo, A-151892 was found to potently suppress unstable bladder contractions in obstructed models of unstable contractions in both pigs and rats with pED(35%) values of 8.05 and 7.43, respectively. 6. These results demonstrate that naphthylamide analogs exemplified by A-151892 are novel K(ATP) channel openers and may serve as chemotypes to exploit additional analogs with potential for the treatment of overactive bladder and lower urinary tract symptoms. 相似文献
84.
Shieh S Fang YV Becker JL Holm A Beutner EH Helm TN 《Cutis; cutaneous medicine for the practitioner》2004,73(5):327-329
Pemphigus vulgaris (PV) is an autoimmune blistering disorder that usually occurs in the fifth and sixth decades of life but may occur at younger ages and during pregnancy. Circulating intercellular antibodies directed at desmosomal proteins may cross the placenta and place children at risk for neonatal pemphigus (NP). We describe the case of a pregnant woman with PV treated successfully with a combination of systemic corticosteroids and plasmapheresis. The possibility of PV should be considered in any pregnant woman with a worsening, widespread, mucocutaneous, blistering disease. Plasmapheresis offers a useful alternative to immunosuppressive therapy in the setting of pregnancy. 相似文献
85.
Lin CC Ng LT Hsu FF Shieh DE Chiang LC 《Clinical and experimental pharmacology & physiology》2004,31(1-2):65-69
1. The present study was conducted to evaluate the cytotoxic effects of Coptis chinensis and Epimedium sagittatum extracts and their major constituents on hepatoma and leukaemia cells in vitro. 2. Four human liver cancer cell lines, namely HepG2, Hep3B, SK-Hep1 and PLC/PRF/5, and four leukaemia cell lines, namely K562, U937, P3H1 and Raji, were used in the present study. 3. Of the two crude drugs, C. chinensis exhibited the strongest activity against SK-Hep1 (IC50 = 7 microg/mL) and Raji (IC50 = 4 microg/mL) cell lines. The IC50 values for C. chinensis on HepG2, Hep3B and PLC/PRF/5 cell lines were 20, 55 and 35 microg/mL, respectively. The IC50 values for C. chinensis on K562, U937 and P3H1 cell lines were 29, 29 and 31 microg/mL, respectively. 4. With the exception of HepG2 and Hep3B, the E. sagittatum extract inhibited the proliferation of all cell lines (SK-Hep1, PLC/PRF/5, K562, U937, P3H1 and Raji), with IC50 values of 15, 57, 74, 221, 40 and 80 microg/mL, respectively. 5. Interestingly, the two major compounds of C. chinensis, berberine and coptisine, showed a strong inhibition on the proliferation of both hepatoma and leukaemia cell lines, with IC50 values varying from 1.4 to 15.2 microg/mL and from 0.6 to 14.1 microg/mL, respectively. However, icariin (the major compound of E. sagittatum) showed no inhibition of either the hepatoma or leukaemia cell lines. 6. The results of the present study suggest that the C. chinensis extract and its major constituents berberine and coptisine possess active antihepatoma and antileukaemia activities. 相似文献
86.
The degree of epitope density has been shown to be a critical factor influencing the magnitude of epitope-specific responses. However, whether high epitope density in just a single protein molecule can still enhance the humoral response or, more importantly, the protective immunity, has not been determined. To test this, five glutathione-S-transferase fusion proteins bearing various numbers of copies of the M2e epitope on M2 protein of influenza virus (1, 2, 4, 8 and 16 copies) were prepared, and used to immunize mice and rabbits. Our data show clearly that M2e-specific humoral response was enhanced with increasing epitope density. By lethal challenge assay in mice, it was observed that recombinant proteins with higher M2e epitope densities resulted in higher survival rates and slower weight losses. The survival rate was directly related to the degree of epitope density in the single recombinant protein: 100% in the case of 16 M2e copies; 50% with 4 M2e epitopes; and 0% with one. 相似文献
87.
Superoxide activates very late antigen-4 on an eosinophil cell line and increases cellular binding to vascular cell adhesion molecule-1 总被引:5,自引:0,他引:5
The recruitment of eosinophils to the airway is a key event in the pathogenesis of allergy. Very late antigen-4 (VLA-4), an integrin ligand for vascular cell adhesion molecule-1 (VCAM-1), is expressed on eosinophils. VLA-4-mediated adhesion of eosinophils to VCAM-1 may contribute to their selective recruitment to tissues in allergy. Reactive oxygen species (ROS), including nitric oxide (NO), are abundant in the airway of allergic patients, but their role in pathogenesis of allergy is unclear. In this investigation, we studied the effects of ROS on integrin-mediated eosinophil adhesion. Recombinant soluble VCAM-1 and ICAM-1 were used to test the effects of ROS on the integrin-mediated adhesion of an eosinophil cell line. We used phorbol 12-myristate 13-acetate-stimulated neutrophils and hypoxanthine to generate superoxide, NO donors as sources of NO, and a static cell-to-protein adhesion assay to analyze cellular adhesion. Stimulated neutrophils significantly increased eosinophil binding to VCAM-1, which was reversed in the presence of superoxide dismutase. Neutrophils from a chronic granulomatous disease patient lacked this activity in enhancing eosinophil adhesion. Our results suggest that the balance between ROS molecules in different tissue microenvironments may change the integrin-mediated leukocyte adhesion and is likely to be a key factor in leukocyte recruitment in allergic inflammation. 相似文献
88.
Ureaplasma urealyticum induces apoptosis in human lung epithelial cells and macrophages 总被引:2,自引:0,他引:2
Chronic lung disease (CLD) of prematurity remains a significant cause of morbidity among premature infants. It is a multifactorial disorder and characterized by an early increased number of neutrophils and alveolar macrophages, with later architectural epithelial and endothelial cell damage. Recently, apoptosis of type 2 pneumocytes in the lung of preterm neonates with acute and chronic lung disease has been examined and apoptosis of mesenchymal cells was detected in the chronic stage of bronchopulmonary dysplasia. Infection and inflammatory responses in the lungs play important roles. However, the contribution of Ureaplasma urealyticum to the development of CLD is debated. We found that U. urealyticum induced apoptosis in human type II lung epithelial cells (A549 cell line) and macrophages (derived from human monocytic cell line THP-1) by measuring the outer leaflets translocation of phosphatidylserine (flow cytometry analysis and fluorescence microscopy assessment), DNA fragmentation analysis, cell morphology changes such as diminution in cell volume, increased cytoplasmic staining, and nuclear pyknosis (hematoxylin and eosin staining) and viable counting (trypan blue exclusion). Anti-TNF-alpha monoclonal antibody partially protected the macrophages from undergoing apoptosis after infection with U. urealyticum. Our findings imply that U. urealyticum might be involved in impairing lung structure and host immune response during the development of CLD. 相似文献
89.
Shieh JS Chang LW Wang MS Sun WZ Wang YP Yang YP 《Medical & biological engineering & computing》2002,40(1):128-136
Pain control in conscious patients was investigated using a push-button, demand-driven supply of drugs. A fuzzy logic patient-controlled
analgesia (PCA) algorithm was compared with a conventional algorithm, for alfentanil administration in extracorporeal shock-wave
lithotripsy. The conventional PCA algorithm used an initial dose of 0.25 mg, a fixed infusion rate of 60 mg h−1 and a fixed bolus size of 0.2 mg with a 1 min lockout. The fuzzy logic PCA algorithm used an initial dose of 0.25 mg, a changeable
infusion rate and a bolus size of 0.1 or 0.05 mg. The infusion rate was adjusted according to a look-up table that accepted
the button-pressing history over the last three lockout intervals. The look-up table was designed using fuzzy logic. The bolus
size was adjusted according to the button-pressing history over the past two lockout intervals. Twelve patients were treated
using conventional PCA, and thirteen were treated with PCA + fuzzy logic control (FLC). PCA+FLC patients consumed 45% less
drug. Also, PCA-FLC patients had a mean delivery/demand ratio of 82%, compared with 60% in conventional PCA. When the pain
intensity scale was analysed, PCA+FLC patients had acceptable pain intensity at 62%, compared with 44% in conventional PCA. 相似文献
90.
Development of an automated immunoassay for advanced glycosylation end products in human serum 总被引:1,自引:0,他引:1
OBJECTIVE: Nonenzymatic reaction of protein and carbohydrate produce a series of brown fluorescent advanced glycosylation end products (AGEs). However, a convenient and rapid assay for serum AGEs level is currently unavailable.METHODS: We raised AGEs-specific polyclonal antibodies, which were used to develop a fully automated, noncompetitive, homogeneous, light-scattering immunoassay for serum AGEs.RESULTS: The assay requires a sample volume of 2 microL and takes a reaction time of 2 min. The coefficient of variation range from 1.8 to 6.1%, and the mean recovery rate was 98.6%. Comparative analysis shows moderate correlation with competitive ELISA (r = 0.8209, n = 52). The mean +/- SD concentration of AGEs in young and in older healthy subjects were 4.6 +/- 1.5 (n = 39) and 4.9 +/- 1.4 (n = 40), respectively. The level of AGEs was significantly higher in serum from patients with type II DM 7.8 +/- 4.8 (n = 89) than that from the normal subjects (p < 0.05).CONCLUSIONS: The automatic immunoassay for AGEs is appropriate for clinical use. 相似文献