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971.
The immunological manifestation of granuloma formations in humans largely depends on the delayed-type hypersensitivity response. We investigated the involvement of monocyte chemoattractant protein-1 (MCP-1) in a rabbit model of T cell-mediated pulmonary granulomatosis. Intravenous injection of Propionibacterium acnes (P. acnes) into sensitized rabbits induced massive and diffuse pulmonary granulomas. Levels of MCP-1 in sera and bronchoalveolar lavage fluids (BALF) peaked before the granuloma formation reached the peak (on days 1 and 3 after challenge, respectively). Chemotactic activities toward monocytes and T cells in BALF were inhibited by anti-MCP-1 IgG by 80 and 36%, respectively. The phenotypic analysis of the migrating T cells revealed that activated and memory T cells rather than naive cells were preferentially attracted to the BALF. Administration of anti-MCP-1 antiserum inhibited the development of granuloma formation in both size and number, the numbers of infiltrating leukocytes in BALF, the expression of adhesion molecules on peripheral monocytes/T cells, and on macrophages/T cells in BALF, and the production of TNF-alpha in the lung. Anti-MCP-1 resulted in a trend toward decreased level of IL-1beta in the lung. The inhibition of the production of these cytokines appeared to be induced indirectly through the inhibition of the recruitment of macrophages that produce these cytokines. The results suggest important roles of MCP-1 in the development of granuloma formation in this model through the attraction and activation of specific types of cells.  相似文献   
972.
Morphine (MOR) is an opioid analgesic used for the treatment of moderate to severe pain. MOR is extensively metabolized to morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G). A rapid and sensitive method that was able to reliably detect at least 0.5 ng/ml of MOR and 1.0 ng/ml of M6G was required to define their pharmacokinetic profiles. An LC-MS-MS method was developed in our laboratory to quantify all three analytes with the required sensitivity and a rapid turnaround time. A solid-phase extraction (SPE) was used to isolate MOR, M3G, M6G, and their corresponding deuterated internal standards from heparinized plasma. The extract was injected on a LC tandem mass spectrometer with a turbo ion-spray interface. Baseline chromatographic separation among MOR, M3G, and M6G peaks was achieved on a silica column with an aqueous organic mobile phase consisting of formic acid, water, and acetonitrile. The total chromatographic run time was 3 min per injection, with retention times of 1.5, 1.9 and 2.4 min for MOR, M6G, and M3G, respectively. Chromatographic separation of M3G and M6G from MOR was paramount in establishing the LC-MS-MS method selectivity because of fragmentation of M3G and M6G to MOR at the LC-MS interface. The standard curve range in plasma was 0.5-50 ng/ml for MOR, 1.0-100 ng/ml for M6G, and 10-1000 ng/ml for M3G. The inter-day precision and accuracy of the quality control (QC) samples were <7% relative standard deviation (RSD) and <6% relative error (R.E.) for MOR, <9% RSD and <5% R.E. for M6G, and <3% RSD and <6% R.E. for M3G. Analyte stability during sample processing and storage were established. Method ruggedness was demonstrated by the reproducible performance from multiple analysts using several LC-MS-MS systems to analyze over one thousand samples from clinical trials.  相似文献   
973.
974.
975.
The circadian changes in the metabolism or nocturnal secretion of endogenous corticosteroids (reduction) observed in rheumatoid arthritis (RA) patients are responsible, in part, for the time-dependent changes that are observed in the inflammatory response and related early morning clinical symptoms of the disease. Melatonin (MLT), another circadian nocturnal hormone that is the secretory product of the pineal gland, has been implicated in the time-dependent RA inflammatory reaction with effects that are opposite to those of corticosteroids. As a consequence, altered functioning of the HPA axis (early morning reduced corticosteroid production) and of the pineal gland (night increased MLT production) found in RA patients, seem to be important factors in the appearance and perpetuation of the clinical circadian symptoms of the disease. Consistently, human proinflammatory Th1-type cytokine production (related to MLT stimulation) exhibits a diurnal rhythmicity with peak levels during the night and early morning, at a time when plasma cortisol (inducing the Th2-type cytokine production) is lowest and MLT is highest. Reduced daily light exposure as observed in northern Europe (Estonia), at least during the winter, might explain the higher and more prolonged serum MLT concentrations that were observed in northern RA patients, as well as some epidemiological features versus southern Europe patients.  相似文献   
976.
Gene deletions in an infertile man with sperm fibrous sheath dysplasia   总被引:1,自引:0,他引:1  
BACKGROUND: Asthenozoospermia may sometimes be related to geneticstructural defects of the sperm tail detectable by transmissionelectron microscopy. Dysplasia of the fibrous sheath (DFS) isa genetic sperm defect, characterized by dysplastic developmentof the axonemal and periaxonemal cytoskeleton. We report thecase of an infertile man with normal sperm count and total spermimmotility in which dysplasia of the fibrous sheath, Akap3,Akap4 gene deletions, meiotic segregation of chromosomes 18,X and Y and Y microdeletions were investigated. METHODS: A 32-year-oldman with a 3-year history of primary infertility presented atour Regional Referral Center for Male Infertility. Family medicalhistory, lymphocyte karyotype, PCR analysis, physical examination,hormone assays and semen analysis were performed. RESULTS: Ultrastructuralsperm evaluation showed dysplasia of the fibrous sheath. Immunostainingof AKAP4 protein was negative in sperm tails. PCR analysis revealedintragenic deletions of the Akap3 and Akap4 genes. Fluorescencein situ hybridization on sperm showed a high frequency of XYdisomy. CONCLUSION: In this infertile patient, our results suggesta possible relationship between dysplasia of the fibrous sheath,partial deletions in the Akap3 and Akap4 genes and absence ofAKAP4 protein in the fibrous sheath. These findings, however,were not detected in another four patients with dysplasia ofthe fibrous sheath. Our results require future confirmatorymolecular analyses.  相似文献   
977.
The aggressive behavior of breast cancer cells can at times be modulated by hormonal mechanisms. Exposure to glucocorticoids (GC) has been shown to stimulate the invasiveness, motility and adhesiveness of breast cancer cells containing the glucocorticoid receptor. This is largely explained by GC-associated overexpression of the c-fms proto-oncogene, which encodes the receptor for the colony stimulating factor-1 (CSF-1). Our objective is to investigate additional GC-associated genetic alterations that could modulate c-fms related malignant behavior in breast cancer cells. A microarray technique using an oligonucleotide array representing 16,700 known expressed human genes was used to analyze the gene expression profile of breast cancer cells exposed to dexamethasone (Dex) or vehicle. Results were confirmed by western blot analysis. Six genes were found to be consistently differentially overexpressed in the Dex-exposed cells compared to control. We focused on serum-glucose kinase 1 (SGK1), a serine-threonine kinase known to be involved in intracellular signal transduction pathways and induced by GC and serum. An adhesion assay was performed on extracellular matrix after exposing the breast cancer cells to Dex, CSF-1 or to Dex or CSF-1 plus LY294002, a functional inhibitor of SGK1 action. Exposure to LY294002 significantly decreased both CSF-1 and Dex-induced adhesiveness to the level of control cells. SGK1 may act as a downstream intracellular regulator of c-fms, particularly of c-fms-induced adhesiveness of breast cancer cells after exposure to GC or CSF-1. This finding may have implications for potential therapeutic interventions aimed at decreasing the aggressiveness of breast cancer cells. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
978.
The HIV/AIDS surveillance system in Japan, which began collecting data on the number of AIDS patients in 1984 and the number of HIV-infected persons in 1987, has played an important role in monitoring the trend and magnitude of Japan's HIV/AIDS epidemic and its distribution across various population subgroups. However, the system lacks any personal identifiers, making it impossible to eliminate duplication or to track cases for disease progression. It also does not permit the identification of the residence of HIV-infected persons because the residence of only the reporting physician is documented under the New Infectious Diseases Control Law, effective since April 1, 1999. The number of people with HIV/AIDS in Japan continues to grow. Among youth, sexually transmitted diseases, induced abortion, and sexual activities have shown a marked increase since the mid-1990s. Behavioral risk of infection for both injection drug users (IDUs) and men who have sex with men (MSM) remains alarmingly high. Accurate monitoring of infection rates is critical to the planning and evaluation of treatment, care and prevention programs. Japan should restructure its HIV/AIDS surveillance system to more accurately monitor the HIV/AIDS epidemic and related risk behaviors.  相似文献   
979.
Exercise and skeletal muscle ageing: cellular and molecular mechanisms   总被引:2,自引:0,他引:2  
As we age, our skeletal muscle becomes smaller and weaker. In addition, the remaining muscle is more susceptible to damage, particularly following exercise, recovery from damage is severely impaired and muscle is unable to adapt rapidly following sequential periods of exercise. The mechanisms by which skeletal muscle damage occurs are poorly understood and the role that an increased production of free radical species plays in this damage is controversial. However, evidence is emerging which suggests that an increased production of free radicals may act as an activator of the adaptive response in skeletal muscle, resulting in the increased production of antioxidant enzymes and heat shock proteins (HSPs). The increased content of these proteins facilitates rapid remodelling of muscle and provides considerable protection against subsequent periods of damaging exercise. There is considerable evidence that the production of free radicals is modified during the ageing process. The aim of this review is to examine the possible effects of this modification on the ability of muscle cells to respond to stress and the functional effect that this may have on our muscles as we age.  相似文献   
980.
The acceleration of nephritis in SNF(1) mice by CD4(+) T-cell clones reactive with a nephritogenic idiotype, Id(LN)F(1) [1], as well as the ability of anti-Id(LN)F(1) antisera to down-regulate the production of Id(LN)F(+)(1) immunoglobulin (Ig) in vivo and delay nephritis [2], suggests that dysregulation of this idiotype may contribute to the development of SNF(1) nephritis. Herein, we show that a monoclonal Id(LN)F(1)-expressing antibody, 540, significantly (P< or = 0.01) stimulated Id(LN)F(1)-reactive T-cell clones B6 and D2 to proliferate, while other Id(LN)F+1 antibodies did not. Further, injection of 540-producing hybridoma cells into nonautoimmune (SWRxBalb/c)F(1) mice resulted in the deposition of Id(LN)F(+)(1) Ig in the kidneys, in a pattern indicative of early nephritis. To identify the pathogenetic Id(LN)F(1) epitope(s) at the molecular level, we compared the deduced amino acid sequences of the heavy and light chain variable regions of pathogenetic and non-pathogenetic Id(LN)F(1)-expressing Igs 540, 317, and 533. Two overlapping peptides derived from the V(H) sequence of 540 (aa 54-66 and 62-73), which both contain the triple basic amino acid motif K(X)K(X)K, stimulated SNF(1) T cells and T-cell clones B6 and D2. These results further support the involvement of a subset of Id(LN)F(1)-expressing Ig in SNF(1) nephritis.  相似文献   
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