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91.
Transmission of hepatitis G virus in patients with angioedema treated with steam-heated plasma concentrates of C1 inhibitor 总被引:2,自引:0,他引:2
F De Filippi; R Castelli ; M Cicardi ; R Soffredini ; MG Rumi ; E Silini ; PM Mannucci ; M Colombo 《Transfusion》1998,38(3):307-311
BACKGROUND: Hepatitis G virus (HGV) is a blood-borne flavivirus that may cause acute and chronic transfusion-transmitted infections. Patients with complement component 1 (C1) inhibitor (C1-INH) deficiency may acquire blood-borne infections through infusion of plasma concentrates. STUDY DESIGN AND METHODS: Serum samples from 84 patients with C1-INH deficiency (19 who received unmodified C1-INH concentrates, 23 who received steam-heated concentrates, and 42 untreated patients) were tested for HGV RNA and hepatitis C virus (HCV) RNA by a nested polymerase chain reaction (PCR). The samples were also tested for antibodies to the E2 envelope protein of HGV (anti-HGV) and to HCV with enzyme-linked immunosorbent assays. RESULTS: Nine (11%) patients had serum HGV RNA; that is, 7 (17%) of 42 patients previously treated with C1-INH concentrates and 2 of 42 previously untreated patients. HGV RNA was as common in the 19 patients treated with unmodified concentrates as in the 23 given steam-heated concentrates (16 vs. 17%, p = 0.60). Anti-HGV was more common among the recipients of unmodified concentrates than among those given steam-heated concentrates (26 vs. 0%, p = 0.014). HCV RNA was more frequently detected in treated patients than in untreated patients (33 vs. 7%, p = 0.005) and in the 19 recipients of unmodified concentrates than in the 23 treated with steam-heated concentrates (58 vs. 16%, p = 0.003). Only one HGV RNA- seropositive patient had elevated serum aminotransferase activity, compared to 11 with HCV RNA. CONCLUSION: HGV was transmitted by both unmodified and steam-heated concentrates, but it caused persistent viremia in a minority of the cases and was rarely associated with liver disease. 相似文献
92.
Objective The aim of this study is to analyse our experience and assess the outcome of surgery for colorectal cancer with curative intent in Greece.Methods During the last 10 years,550 patients were treated for colorectal cancer with curative intent.291(52.9%) of the patients suffered from colonic cancer while 259(47.1%) were operated for rectal cancer.Tumour site,Astler?Coller and TNM classifications and surgical procedures were recorded.Total mortality,morbidity and 5?year survival were evaluated.Results Morbidity rate was 12.0% and mortality rate was 0.68% for colonic cancer surgery,whereas the overall five year survival rate was 77.9%.Morbidity rate was 16.9% and mortality rate was of 0.38% for rectal cancer patients.The overall five year survival rate was 79.6%.Conclusion Morbidity,mortality rate and 5?year survival after colorectal surgery in our department in Greece are comparable to those published in the international literature. 相似文献
93.
Rosamma Joseph MG Jose Raj Shobha Sundareswaran Priyanka Chand Kaushik Amol Vijay Nagrale Susan Jose Sreeraj Rajappan 《World Journal of Rheumatology》2014,4(3):80-87
Periodontitis or Periodontal disease(PD) and Rheumatoid arthritis(RA) are two the most common chronic inflammatory diseases. Periodontitis is a biofilm associated destructive inflammatory disease of the periodontium caused by specific microorganisms. Rheumatoid arthritis is an autoimmune condition and is identified by elevated serum autoantibody titre directed against citrullinated peptides or rheumatoid factor. Periodontitis may involve some elements of autoimmunity. Recent studies have established that PD and RA show a common pathway and could be closely associated through a common dysregulation and dysfunction in inflammatory mechanism. The enzyme peptidyl arginine deiminase(PAD), expressed by Porphyromonas gingivalis(P. gingivalis) is responsible for the enzymatic deimination of arginine residuals to citrulline resulting in protein citrullination and its increased accumulation in RA.Citrullination by PAD may act as a putative biologic link between PD and RA. Association of Human leukocytic antigen-DR4 antigen has been established both with RA and PD. Several interleukins and inflammatory mediators(ILs) and Nuclear factor kappa beta ligand are linked to these common chronic inflammatory diseases. Antibodies directed against heat shock protein(hsp 70 ab) of P. gingivalis, P. melanogenicus and P. intermedia are raised in PD as well as RA. Both the conditions share many pathological and immunological similarities. Bacterial infection, genetic susceptibility, altered immune reaction and inflammatory mediators considered responsible for RA are also associated with PD. So it is plausible that a biological link may exist between PD and RA. Therapies aimed at modifying the expression and effect of inflammatory mediators and effector molecules such as matrix metalloproteinases, proinflammatory cytokines and autoantibodies of structural proteins may probably reduce the severity of both RA and PD. 相似文献
94.
95.
Proteoglycans in human long-term bone marrow cultures: biochemical and ultrastructural analyses 总被引:7,自引:2,他引:5
Proteoglycans within the extracellular matrix of human bone marrow have been implicated in the process of hematopoiesis, but little is known about the structure and composition of these macromolecules in this tissue. Hematopoietically active human long-term bone marrow cultures were incubated with medium containing 35S-sulfate and 3H-glucosamine as labeling precursors. Proteoglycans present in the medium and cell layer were extracted with 4 mol/L guanidine HCI and purified by diethylaminoethyl (DEAE)-Sephacel ion exchange and molecular sieve chromatography. Both culture compartments contain a large chondroitin sulfate proteoglycan (MI, CI) that eluted in the void volume of a Sepharose CL-4B column and contained glycosaminoglycan chains of molecular weight (mol wt) approximately 38,000. A second population of sulfate-labeled material was identified as a broad heterogenous peak (MII, CII) that was included on Sepharose CL-4B at Kav = 0.31. This material when chromatographed on Sepharose CL-6B could be further separated into a void peak (MIIa, CIIa) and an included peak eluting at Kav = 0.39 (MIIb, CIIb). The void peaks (MIIa, CIIa) were susceptible to chondroitinase ABC digestion (99%) but slightly less susceptible to chondroitinase AC digestion (90%). Papain digestion of these peaks revealed them to be proteoglycans with glycosaminoglycan chains of mol wt approximately 38,000. The included peaks on Sepharose CL-6B (MIIb, CIIb) from both medium and cell layer compartments resisted digestion with papain, indicating the presence of glycosaminoglycan chains of mol wt approximately 38,000 either free or attached to a small peptide. Although this material was susceptible to chondroitinase ABC (98%), it was considerably less susceptible to chondrotinase AC (approximately 60%), indicating that it contained dermatan sulfate. A small amount of heparan sulfate proteoglycan was also identified but constituted only approximately 10% of the total sulfated proteoglycan extracted from these cultures. Additionally, approximately 40% of the incorporated 3H- activity radioactivity was present as hyaluronic acid. Electron microscopy revealed a layer of adherent cells covered by a mat containing ruthenium red-positive granules that were connected by thin filaments. The extracellular matrix layer above the adherent cells contained a mixture of hematopoietic cells. Chondroitinase ABC treatment of the cultures completely removed the ruthenium red-positive granules overlying the cells and resulted in a loss of approximately 70% of the 35S-sulfate-labeled material from the cell layer.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
96.
97.
The occipitoparietal pathway of the macaque monkey: comparison of pyramidal cell morphology in layer III of functionally related cortical visual areas 总被引:13,自引:12,他引:1
The dendritic morphology of pyramidal cells located at the base of layer
III in the primary visual area (V1), the second visual area (V2), the
middle temporal area (MT), the ventral portion of the lateral intraparietal
area (LIPv) and in the portion of cytoarchitectonic area 7a within the
anterior bank of the superior temporal sulcus was revealed by injecting
neurons with Lucifer Yellow in fixed, flattened slices of macaque monkey
visual cortex. These areas correspond to different levels of the
occipitoparietal cortical 'stream', which processes information related to
motion and spatial relationships in the visual field. The tissue was
immunocytochemically processed to obtain a light-stable diaminobenzidine
reaction product, revealing the dendritic morphology in fine detail.
Retrogradely labelled MT- projecting neurons in supragranular V1 (layer
IIIc of Hassler's nomenclature, corresponding to Brodmann's layer IVb) were
predominantly pyramidal, although many spiny multipolar (stellate) cells
were also found. The average basal dendritic field area of pyramidal
neurons in sublamina IIIc of V1 was significantly smaller than that in the
homologous layer of V2, within the cytochrome oxidase-rich thick stripes.
Furthermore, the average basal dendritic field areas of V1 and V2 pyramidal
neurons were significantly smaller than those of neurons in MT, LIPv and
area 7a. There was no difference in basal dendritic field area between
layer III pyramidal neurons in areas MT, LIPv and 7a. While the shape of
most basal dendritic fields was circularly symmetrical in the dimension
tangential to the cortical layers, there were significant biases in
complexity, with dendritic branches tending to cluster along particular
axes. Sholl analysis revealed that the dendritic fields of neurons in areas
MT, LIPv and 7a were significantly more complex (i.e. had a larger number
of branches) than those of V1 or V2 neurons. Analysis of basal dendritic
spine densities revealed regional variations along the dendrites, with peak
densities being observed 40-130 microns from the cell body, depending on
the visual area. The peak spine density of layer III pyramidal neurons in
V1 was lower than that observed in V2, MT or LIPv, which were all similar.
Pyramidal neurons in area 7a had the greatest peak spine density, which was
on average 1.7 times that found in V1. Calculations based on the average
spine density and number of dendritic branches at different distances from
the cell body demonstrated a serial increase in the total number of basal
dendritic spines per neuron at successive stations of the occipitoparietal
pathway. Our observations, comparing dendritic fields of neurons in the
homologous cortical layer at different levels of a physiologically defined
'stream', indicate changes in pyramidal cell morphology between
functionally related areas. The relatively large, complex, spine-dense
dendritic fields of layer III pyramidal cells in rostral areas of the
occipitoparietal pathway allow these cells to sample a greater number of
more diverse inputs in comparison with cells in 'lower' areas of the
proposed hierarchy.
相似文献
98.
A Toll†¶ R Celis‡ MD Ozalla† M Bruguera§ C Herrero† MG Ercilla‡ 《Journal of the European Academy of Dermatology and Venereology》2006,20(10):1201-1206
OBJECTIVES: To investigate the role of C282Y and H63D mutations, and hepatitis C virus (HCV) infection in the pathogenesis of porphyria cutanea tarda (PCT). DESIGN: Prospective case-control study. SETTING: A large clinical and research institute for the study and treatment of cutaneous diseases in Barcelona, Spain. PATIENTS: Ninety-nine consecutive patients with PCT and one hundred and twenty-six control patients (76 healthy subjects and 50 patients chronically infected with HCV), were recruited. MAIN OUTCOME MEASURES: The frequency of the C282Y and H63D mutations in patients with PCT vs. controls and the relationship of these mutations with HCV infection, and iron status, as judged by serum iron, liver iron and ferritin levels. RESULTS: C282Y mutation was significantly increased in PCT patients. This mutation was more frequent among non-HCV-infected patients. Increased ferritin levels and hepatic iron overload were also observed in PCT patients with heterozygous C282Y state. H63D mutation was only significantly increased among PCT patients with chronic hepatitis C infection. No significant iron overload was observed in patients with H63D mutation. CONCLUSIONS: This study confirms the high frequency of C282Y mutation in patients with PCT and its relationship with iron overload. The C282Y mutation has a relevant role in Spanish patients with PCT not associated with HCV chronic infection. On the other hand, the prevalence of the H63D mutation seems not to be increased in patients with PCT. The possibility of an association between HCV infection and H63D mutation in inducing PCT can be hypothesized. 相似文献
99.
The Landsteiner-Wiener (LW) blood group antigens reside on a 42-kD erythrocyte membrane glycoprotein that has recently been cloned. Here, we found that the molecular basis for the LWa/LWb polymorphism is determined by a single base pair mutation (A308G) that correlates with a Pvu II restriction site and results in a Gln70Arg amino acid substitution. COS-7 cells transfected with LWa or LWb cDNAs reacted with human anti-LWa and anti-LWb sera, respectively, as well as with a murine monoclonal anti-LWab antibody, as shown by flow cytometry analysis. Moreover, a 42-kD protein was immunoprecipitated from the transfected cells with the monoclonal anti-LWab antibody. These findings indicate that LWa and LWb are alleles of the LW blood group locus as defined also by a monoclonal anti-LWab of nonhuman origin. In addition, the LW locus has been assigned to chromosome 19p13.3 by in situ hybridization. Study by Southern blot analysis indicated also that the LW locus is composed of a single gene that was not grossly rearranged in rare LW(a-b-) and Rhnull individuals deficient for LW antigens. In addition, Pvu II restriction fragment-length polymorphism analysis indicated that these variants were all homozygous for a phenotypically silent LWa allele. 相似文献
100.