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71.
Ki CS Lee WY Han DH Sung DH Lee KB Lee KA Cho SS Cho S Hwang H Sohn KM Choi YJ Kim JW 《Journal of human genetics》2002,47(9):473-477
Hereditary spastic paraplegia (HSP) is a group of clinically and genetically heterogeneous neurodegenerative disorders characterized
by slowly progressive spasticity and weakness of the lower extremities. Among eight loci linked with autosomal-dominant (AD)-HSP,
the SPG4 locus on chromosome 2p22 accounts for about 40% of all patients. Recently, mutations in a new member of the AAA protein family,
called spastin, have been identified as responsible for SPG4-linked AD-HSP. Here, we describe a novel missense mutation (c.1031T>A; I344K) in exon 7 of the SPG4 gene identified in a Korean family with typical clinical features of pure AD-HSP. The mutation affects the third amino acid
of the highly conserved AAA cassette domain, which is the most fore part of the domain altered by a missense mutation reported
so far. Clinical presentations of affected individuals carrying the I344K mutation were not different from those of pure AD-HSP
with SPG4 mutations reported previously. However, it is noteworthy that neither urinary dysfunction nor involvement of upper extremities
was noticed in this family. To our knowledge, this is the first report of genetically confirmed AD-HSP in Korea.
Received: February 20, 2002 / Accepted: May 21, 2002 相似文献
72.
Esophageal ulceration triggers expression of hypoxia-inducible factor-1 alpha and activates vascular endothelial growth factor gene: implications for angiogenesis and ulcer healing
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Baatar D Jones MK Tsugawa K Pai R Moon WS Koh GY Kim I Kitano S Tarnawski AS 《The American journal of pathology》2002,161(4):1449-1457
73.
Kim YS Cheon KA Kim BN Chang SA Yoo HJ Kim JW Cho SC Seo DH Bae MO So YK Noh JS Koh YJ McBurnett K Leventhal B 《Yonsei medical journal》2004,45(1):81-89
In order to develop a structured and objective diagnostic instrument, authors completed: (1) the translation and back translation of the Korean version of the Kiddie-Schedule for Affective Disorders and Schizophrenia - Present and Lifetime Version (K-SADS-PL) and (2) the examination of its validity and reliability of the K-SADS-PL-Korean version (K-SADS- PL) when used with Korean children. A total of 91 study subjects were recruited from child and adolescent psychiatry outpatient clinics. Clinical diagnoses were used as a gold standard for the examination of validity of K-SADS-PL-K. Consensual validity of threshold and sub-threshold diagnoses were good to excellent for attention-deficit/hyperactivity disorder (ADHD), fair for tic and oppositional defiant disorders, and poor to fair for anxiety and depressive disorders. Inter-rater and test-retest reliabilities were fair to excellent for ADHD and tic disorder. The significant correlations between the K-SADS-PL-K and Korean Child Behavior Checklist (K-CBCL) were found, which provided additional support for the concurrent validity of the K-SADS-PL-K. Sensitivities varied according to the diagnostic categories, but specificities remained high over all diagnoses, suggesting that the K-SADS-PL-K is a desirable confirmatory diagnostic tool. The results of this study suggest that the K-SADS-PL-K is an effective instrument for diagnosing major child psychiatric disorders, including ADHD, behavioral disorders and tic disorders in Korean children. Future studies will examine the validity and reliability of the K-SADS-PL-K in larger samples, including adolescents and community samples on a variety of child and adolescent psychiatric disorders. 相似文献
74.
Pseudotype hepatitis C virus enters immature myeloid dendritic cells through the interaction with lectin 总被引:3,自引:0,他引:3
Kaimori A Kanto T Kwang Limn C Komoda Y Oki C Inoue M Miyatake H Itose I Sakakibara M Yakushijin T Takehara T Matsuura Y Hayashi N 《Virology》2004,324(1):74-83
Dendritic cells (DC) are the most potent antigen-presenting cells that regulate immune responses. One of the mechanisms for hepatitis C virus (HCV) persistence is the ability of HCV to suppress DC function. Direct HCV infection to blood DC has been implicated for DC dysfunction. To clarify the susceptibility of each DC subset to HCV, we used pseudotype vesicular stomatitis virus (VSV) coated with chimeric HCV envelope glycoproteins (E1 and E2). We demonstrate that pseudotype VSV enters myeloid DC (MDC) but not plasmacytoid DC (PDC). The highest efficiency of pseudotype VSV entry to MDC was observed when MDC were cultured with GM-CSF. Such efficiency decreased when MDC are matured with the treatment of IL-4, CpG oligodeoxynucleotide, or CD40 ligand. Mannan inhibited pseudotype VSV entry to MDC, but Ca(2+) chelators failed to do so. These results show that pseudotype VSV possessing HCV-E1 and E2 enters immature MDC through the interaction with lectins in a Ca(2+)-independent manner. 相似文献
75.
Distribution patterns and the relative frequency of different types of endocrine cells were demonstrated in the alimentary tract of the grass lizard, Takydromus wolteri, using nine specific antibodies raised against mammalian regulatory peptides. The alimentary tract of the lizard was divided into six portions from the esophagus to the rectum. Most endocrine cells were found in the epithelial lining and were generally spindle shaped with long cytoplasmic processes ending in the lumen (open cell type), whereas cells that were spherical in shape (closed cell type) were occasionally found in gastric, esophageal and intestinal glands. Endocrine cells were stained for the following regulatory peptides: bovine Sp-1/chromogranin (BCG), serotonin, somatostatin, gastrin, cholecystokinin (CCK)-8, glucagon, insulin, human pancreatic polypeptide (HPP) and secretin. Cells stained for BCG and serotonin were present throughout the entire gastrointestinal tract and they occurred with the highest frequency in stomach and pylorus, respectively. Somatostatin-positive cells were detected throughout the entire gastrointestinal tract except for the esophagus and large intestine, and were most predominant in pylorus and duodenum. Cells stained for gastrin were restricted to the pylorus and duodenum and occurred with a relatively low frequency. CCK-8-positive cells were observed from pylorus to small intestine and showed the highest frequency in the pylorus. Glucagon- and insulin-containing cells were located in duodenum and small intestine but were found only rarely. HPP-stained cells were detected in duodenum and small intestine with the highest frequency in duodenum. Cells stained for secretin were restricted to duodenum and were found only rarely. In conclusion, distribution patterns and the relative frequency of these endocrine cells correspond well with previous reports on distribution patterns of endocrine cells in reptile species but some deviating patterns were also observed. 相似文献
76.
A discrete-time kinetic model for chemotherapy was developed to deal with the effects of antitumor drugs on the cell cycle
and proliferation kinetics of experimental tumor cell populations in which cell kinetic responses of chemotherapy are represented
in terms of perturbation of cell kinetic parameters—cell age, cell size and DNA content distributions. The time-course behavior
of these cell kinetic parameters was predicted by solving the discrete-time state equations which characterize the dynamics
of tumor-drug interactions. The amount of antitumor drug administered was expressed to be the control function of the state
equations and the transition matrix representing two modes of drug action, namely, cell kill and progression delay or accumulation
of cells due to drug, was derived. The performance of the model, assessed by examining the effects of cell cycle stage-specific
agents such as cytosine arabinoside on spontaneous AKR leukemia, compared favorably with experimental data. Utilizing an optimization
scheme in engineering systems studies, an analytical method is described for optimizing the regimen of drug administration
so as to maximize the effectiveness of drug dosage schedules and minimize the use of toxic amounts of the drug. The superiority
of the schedule designed by an optimization scheme was evident at the termination of therapy, although the schedule designed
by experimental trials reduced the number of surviving tumor cells more effectively than the one designed by an optimization
scheme during the earlier therapy period. In the model, the proposed schedule will function more effectively for the entire
therapy period when additional parameters of drug characteristics, such as the toxicity to the host and drug resistance, are
encompassed. 相似文献
77.
Jang SH Seol JY Kim CH Yoo CG Kim YW Han SK Shim YS Lee CT 《International journal of molecular medicine》2004,13(1):181-186
TRAIL is a cytokine that can induce tumor-specific apoptosis through its specific death receptors (DR4 and DR5) and p53 has been proven to increase the expression of death receptors. To examine their interaction in tumor suppression, p53 and TRAIL genes were inserted in recombinant adenovirus vectors and transferred simultaneously into non-small cell lung cancer cell lines (NCI-H157, NCI-H358, NCI-H460 and A549). Western blot assay demonstrated production of TRAIL protein in NCI-H157 and A549 cell lines. Increased expressions of DR4 and DR5 of NCI-H157 and DR4 of A549 after p53 overexpression were confirmed by flow cytometry. p53 or TRAIL gene transfer increased sub-G1 fraction in cell cycle analysis and inhibited the tumor growth dose-dependently and the degree was potentiated by co-transfer. But isobologram analysis indicated an additive effect. Together, these data indicate that p53 and TRAIL interact additively on tumor apoptosis despite theoretical synergism. 相似文献
78.
79.
Pathogenicity of Treponema pallidum may depend upon the binding of Treponema pallidum to matrix proteins, especially to fibronectin. Infectious organism or cell to matrix interactions are mediated by a family of adhesion molecule receptors known as integrins. Once in the host, the pathogenic Treponema pallidumdum adheres to the vascular endothelium and readily penetrates surrounding tissues. Fibronectin plays an important role in the mediation of the attachment of Treponema pallidum to host cells, including endothelial cells. We found that the binding of Treponema pallidum to human dermal microvascular endothelial cells and to a glass surface coated with fibronectin is inhibited by the presence of arginine-glycine- aspartic acid (RGD), and analysis of the surface receptor revealed an antigenic similarity to an integrin molecule, namely alpha5. This ability to adhere to host endothelium and fibronectin is quite unique to T. pallidum among the treponemes, and may be a key pathogenic factor. 相似文献
80.
Kim CK Kim SW Park CS Kim BI Kang H Koh YY 《The Journal of allergy and clinical immunology》2003,112(1):64-71
BACKGROUND: The pathogenetic basis for the relationship between acute bronchiolitis and asthma has not yet been completely elucidated. OBJECTIVE: The aim of this study was to compare these 2 diseases in terms of their patterns of airway cytokine response (T(H)1 or T(H)2). METHODS: By using a bronchoalveolar lavage (BAL) technique, this study investigated the cytokine levels of BAL fluid in children with acute asthma who had no identifiable respiratory syncytial virus (RSV) infection (n = 18) and in infants with acute bronchiolitis caused by RSV (n = 22). Comparisons were made with normal control subjects (n = 14). IFN-gamma (T(H)1) and IL-4 and IL-5 (T(H)2) levels were measured in concentrated BAL fluids by means of ELISA. RESULTS: The IL-5 level (P <.001) and IL-5/IFN-gamma ratio (P <.001) were significantly increased in the asthmatic group with no identifiable RSV infection and in the RSV-induced bronchiolitis group compared with values in the control group. When infants in the bronchiolitis group were divided into eosinophil-positive and eosinophil-negative subgroups, the eosinophil-positive subgroup had significantly increased IL-5 levels (P <.001) and IL-5/IFN-gamma ratios (P <.01) compared with those in the control group, but similar cytokine responses were not induced in the eosinophil-negative subgroup. The percentage of BAL eosinophils correlated significantly with levels of BAL IL-5 in both the asthma group (r = 0.80, P =.000) and the bronchiolitis group (r = 0.82, P =.000). CONCLUSIONS: These findings suggest that a subgroup of the RSV-induced bronchiolitis group results in a T(H)2-type response, and this could provide a valuable framework to explain the link between RSV-induced bronchiolitis and asthma. 相似文献