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151.
In an eosinophilic population of 47 boys of the same age, a large proportion (92%) were helminth infested or atopic, or both, compared with 36% of 36 controls. The methods used to detect these conditions were not costly or elaborate, except for the radioallergosorbent test, which was used to measure concentrations of circulating IgE antibodies to atopic allergens. It is suggested that an economical approach to detect helminthiasis and atopy in cases of eosinophilia is adopted using the methods employed here, with skin prick tests replacing the radioallergosorbent test. 相似文献
152.
Monocyte/macrophage activation by normal bacteria and bacterial products: implications for altered epithelial function in Crohn's disease 总被引:2,自引:0,他引:2 下载免费PDF全文
Zareie M Singh PK Irvine EJ Sherman PM McKay DM Perdue MH 《The American journal of pathology》2001,158(3):1101-1109
Intestinal immune cells are less reactive than those in the peripheral blood; however, such cells from patients with Crohn's disease may be more responsive to bacterial products. Our study examined if nonpathogenic bacteria or lipopolysaccharide (LPS), can affect epithelial function in the presence of monocytes/macrophages. Lamina propria mononuclear cells (LPMCs) and peripheral blood monocytes (PBMs) were obtained from patients with Crohn's disease and control patients. Filter-grown T84 epithelial monolayers were co-cultured with nonactivated or LPS-activated LPMCs or PBMs for 48 hours. Epithelial secretory [baseline short-circuit current (Isc) and DeltaIsc to forskolin] and barrier (transepithelial electrical resistance) parameters were measured in Ussing chambers. LPS-activated PBMs from both controls and patients with Crohn's disease significantly increased Isc ( approximately 300%) and reduced transepithelial electrical resistance ( approximately 40%). Epithelial function was not altered after co-culture with control LPMCs +/- LPS. However, LPMCs from patients with Crohn's disease spontaneously secreted tumor necrosis factor-alpha, and induced epithelial changes similar to those produced by LPS-activated PBMs. Co-culture with control Escherichia coli and PBMs induced comparable changes in epithelial physiology, which were abrogated by anti-tumor necrosis factor-alpha antibody. We conclude that LPMCs of patients with Crohn's disease are spontaneously activated, possibly by gram-negative luminal bacteria, and can directly cause significant alterations in epithelial ion transport and barrier functions. 相似文献
153.
The nucleotide sequence of the 3' terminal 2022 nucleotides (nt) of tobacco ringspot virus (TobRV) RNA 2 has been determined. Protein microsequence analysis of the amino-terminal residues of purified capsid protein localized the capsid protein gene between nt 2014 and 583 (from the 3' terminus) of this sequence. The proteolytic cleavage site that is processed to liberate the capsid protein from the RNA 2-encoded polyprotein was identified as Cys-Ala. The predicted translation product from the gene is a 477 amino acid long polypeptide with a calculated MW of 53 kDa. The gene was modified at the 5' end to facilitate sub-cloning, and to provide it with a methionine initiation codon. The modified gene was sub-cloned, transcribed in vitro and expressed in a rabbit reticulocyte lysate translation system, where it directed the synthesis of a 53 kDa polypeptide. Garnier-Osguthorpe-Robson analyses of the secondary structure of the capsid protein predicted the presence of three beta sheet domains, which suggests that this nepovirus capsid may be structurally analogous to those of the como- and picornaviruses. These and other results from computer analyses of the nucleic acid and amino acid sequences, and comparisons with the capsid proteins of nepoviruses and other related viruses are discussed. 相似文献
154.
Characterization of Pseudomonas aeruginosa adherence to mouse corneas in organ culture. 总被引:1,自引:5,他引:1 下载免费PDF全文
The present study was designed to obtain further information on the nature of the corneal macromolecule(s) to which Pseudomonas aeruginosa adheres and how adherence might be prevented. Scarified adult mouse corneas in organ culture were treated with trypsin or lipase to determine whether the receptor molecule(s) was protein or lipid in nature. Trypsin (20 micrograms/ml) treatment of the cornea for 5 min had no significant effect on bacterial adherence, and longer periods of enzyme exposure resulted in extensive surface cell lysis. In contrast, lipase treatment (50,000 U/ml) for 1 h caused little visible cell lysis and significantly reduced bacterial adherence. To test further the lipid nature of the receptor, a highly purified monosialoganglioside (GM1) preparation (500 micrograms/ml) was used to preincubate (1 h) the cornea prior to bacterial application, and this also inhibited bacterial adherence. Similar corneal treatment with gangliotetraosylceramide (asialo GM1) (500 micrograms/ml) had little effect on ocular bacterial binding. Premixing of the bacterial inoculum with GM1 prior to corneal application had no significant effect on inhibiting bacterial binding, but similarly premixing the bacterial inoculum with asialo GM1 transiently decreased adherence. Lastly, premixing of the bacterial inoculum or preincubation of corneas with fibronectin (500 micrograms/ml for 1 h) both decreased bacterial adherence. These findings provide evidence that the receptor-adhesin interactions of P. aeruginosa at the ocular surface in organ culture are complex, involve a glycolipid moiety, and may be blocked by a ganglioside containing at least one sialosyl residue or by fibronectin, which may bind to membrane-associated gangliosides. 相似文献
155.
Fungal allergens have been found to be one of the most prevalent aeroallergens in India. Knowledge of shared/unique components among different fungi is necessary for proper diagnosis and treatment of patients allergic to fungi. In the present study, crude extracts (CE) of 11 common fungi (Alternaria alternata, Aspergillus flavus, Asp. fumigatus, Asp. niger, Asp. tamarii, Asp. versicolor, Cladosporium herbarum, Curvularia lunata, Mucor hiemalis, Penicillium citrinum, and Fusarium solani) were characterized by isoelectric focusing (IEF), SDS-PAGE, and immunoblot. On IEF (pI 3–9), the number of protein bands was found to be greatest (46) in M. hiemalis extract. SDS-PAGE exhibited a varied number of bands, generally 18–40, with mol. mass ranging from 14 to 100 kDa. IgG-specific immunoprint using rabbit anti-F. solani CF antibodies demonstrated a mol. mass distribution of shared antigenic proteins of 14–100 kDa in most of the fungi. Shared allergenicity was observed in a number of allergenic proteins in fungal extracts with mol. mass ranging between 14 and 70 kDa on IgE-specific immunoblot using pooled sera of patients allergic to Fusarium. A 45-kDa protein was found to be common among these fungi on immunoblot with patients as well as with rabbit antibodies. F. solani CF extract contained more antigenic/allergenic proteins than F. solani CE. It was concluded that F. solani CF shared several antigenic/allergenic components with CE of other common fungi. This fact needs to be taken into account when fungal extracts are used in diagnosis and immunotherapy of allergic patients. 相似文献
156.
L J Yonk R P Warren R A Burger P Cole J D Odell W L Warren E White V K Singh 《Immunology letters》1990,25(4):341-345
CD4+ (helper) T cells are a heterogenous population of lymphocytes including at least two distinct subpopulations. To investigate the possibility that immune abnormalities in some subjects with autism may involve abnormal distributions of CD4+ and/or CD8+ cells, (suppressor) T cells, peripheral blood lymphocytes of 25 autistic subjects were characterized with monoclonal antibodies and flow cytometry. The autistic subjects had a significantly lower percentage and number of CD4+ cells, a lower number of T cells (CD2+ cells) and B cells (CD20+ cells), and a lower percentage and number of total lymphocytes than siblings and normal subjects. The level of blood values for female subjects appeared lower than those for males as compared to normal subjects of the same sex. These results suggest that a decrease in CD4+ cells is associated with autism. 相似文献
157.
The present investigation was carried out for increasing the yield of tannase of Aspergillus niger and the physico-chemical characterization of this enzyme. the extraction of enzyme protein. However, extraction of fungal pigments and proteins was observed to have high pH dependence, and maximum enzyme extraction was obtained at pH 5.5. The two-step purification protocol gave 51-fold purified enzyme with a yield of 20%. The total tannase activity was made up of nearly equal activity of esterase and depsidase. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis of purified tannase protein indicated it to be made up of two polypeptides of molecular weight 102 and 83 kDa. Based on the Michaelis-Menten constant (Km) of tannase for three substrates tested, tannic acid was the best substrate with Km of 2.8 x 10(-4) M, followed by methyl gallate and propyl gallate. The inhibition was maximum for CaCl2 (58%) whereas EDTA had no modulatory effect on tannase activity. The inhibitor binding constant (KI) of CaCl2 was 5.9 x 10(-4) M Homogenization and detergent pretreatments did not have any remarkable effect on and the inhibition was of noncompetitive type. 相似文献
158.
159.
Richmond FJ Singh K Corneil BD 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1999,125(1):14-18
Obliquus capitis inferior (OCI) is a monoarticular suboccipital muscle linking the transverse process of the atlas (C1) to
the spinous process of the axis (C2). Histochemical analysis of fiber-type composition showed that the muscle has a marked
gradient of fiber-type distribution in which type I fibers comprise 95–100% of fibers in the deepest region but less than
10% of fibers in the superficial layer. Step-like changes in fiber-type proportions occurred between groups of fascicles.
In most instances the boundaries between these fascicles did not exhibit different perimysial features from those fascicles
with similar fiber-type proportions. OCI contained large numbers of muscle spindles, which were concentrated in deep regions
rich in type I fibers. The degree of nonuniformity in fiber-type distribution seen in OCI is unusually large when compared
with patterns described in other primate muscles, and has implications for the way that the muscle is studied anatomically
and physiologically.
Received: 11 August 1998 / Accepted: 23 September 1998 相似文献
160.
Present pilot study was conducted to evaluate efficacy and safety of polyunsaturated phosphatidyl choline (PPC) in a phase III clinical trial in patients of fulminant and subacute hepatic failure over one year period in a prospective randomised blinded controlled design. We found that in patients of fulminant hepatic failure, recovery period from encephalopathy was faster and mortality rate lower in the test group of patients who received PPC in a dose of 350 mg thrice daily for 6 to 8 weeks as compared to the control groups who did not receive it. In the patients of subacute hepatic failure, recovery from encephalopathy was faster, mortality rate lower and regression of ascites was significantly higher (P = 0.0022) in test group of patients who received PPC as compared to the control group. However, as the number of patients in the present pilot study is small, we propose that larger clinical trials are warranted in this direction to prove the efficacy and safety of PPC in fulminant and subacute hepatic failure. 相似文献