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991.
A diet containing adequate amounts of protein rapidly suppresses myofibrillar protein degradation after refeeding in young rats and mice. However, it is unclear whether this suppression is seen in adult animals. This study was undertaken to compare dietary protein-induced suppression of myofibrillar protein degradation in young and adult mice. Reductions in rates of myofibrillar protein degradation measured by N-methylhistidine (MeHis) released from the isolated extensor digitorum longus muscle were found at 4 to 7 h after refeeding in both young (7-wk-old) and adult (8-mo-old) mice, indicating that the response time of feeding-induced suppression of myofibrillar protein degradation was the same. When young (8-wk-old) mice were fed a 20% casein diet (20C) for 1 h after 18 h starvation, the rate of myofibrillar protein degradation was significantly decreased at 4 h after refeeding; however, mice fed a 10% casein diet (10C), 5% casein diet (5C), or protein-free diet (0C) did not show suppression of myofibrillar protein degradation. Adult (8-mo-old) mice fed 20C or 10C showed a reduction in the rate of MeHis release. The plasma concentration of leucine in young mice was only higher when they were fed 20C. Adult mice fed 20C or 10C showed higher plasma concentrations of leucine. These results suggest that postprandial suppression of myofibrillar protein degradation occurs in adult mice as in young mice, but the adult mice respond to a lower amount of dietary casein compared to the young mice.  相似文献   
992.
A new alpha-glucosidase inhibitor, penasulfate A, has been isolated from a marine sponge Penares sp.(1) Its structure was elucidated by spectral and chemical methods to be a scalemic mixture of methyl pipecolates acylated with a novel sulfated fatty acid.  相似文献   
993.
We report 3 gastric cancer patients with peritoneal dissemination who failed to take TS-1 due to adverse effects and who were successfully treated with weekly paclitaxel administered intravenously. The patients were 2 men and 1 woman from 73 to 82 years in age. The histological types of gastric cancer were undifferentiated adenocarcinoma in all cases. Intravenous infusion of TXL (62-80 mg/m2) after short premedication was continued for 3 weeks followed by 1 week rest. Clinical symptoms, including ascites and intestinal obstruction, improved only after administration of 1 cycle in all patients. Except for 1 event with grade 3 neutropenia, no major adverse reactions were observed. Weekly administration of paclitaxel may be a promising chemotherapy for controlling peritoneal metastasis and improving the quality of life of patients with advanced or recurrent gastric cancer.  相似文献   
994.
Although an expression of MHC molecules and tumor associated antigens of the cancer are not uniform, we consider that the cancer immunotherapy for some specific tumor antigens cannot correspond to molecular biological varieties of the cancer. Consequently, we tried to develop a method to separate dendritic cells (DC), T-cells and natural killer (NK) cells from peripheral blood mononuclear cells (PBMC) obtained from healthy volunteers. PBMC were separated by centrifugation on Ficoll-Hypaque gradients from peripheral blood obtained from healthy volunteers. After separating these cells, the cells were put into a plastic flask, and we isolated monocyte fraction (dendritic cells), NK cell fraction and T-cell fraction one after another by the difference in its ability to adhere to a plastic flask. We analyzed surface markers and activation states of these groups. We could induce dendritic cells from the monocyte fraction, CD3-activated T-cells (CAT) from the T-cell fraction, and adherent lymphokine activated-killer cells (A-LAK) from the NK cell fraction. Therefore, we indicate the possibility of the combined cell therapy with three immune cell fractions in which we can induce from the same blood at once.  相似文献   
995.
Gallbladder cancer has a dismal prognosis. Understanding the disease at the biological, genetic, molecular, cellular, and clinical level is essential for effective diagnostics and therapeutics. However, the currently established gallbladder cell lines are insufficient for better understanding and further research. The aim of our present study was to establish and characterize human gallbladder cancer cell lines. We established 5 cell lines from resected specimens of gallbladder cancers. These cell lines revealed typical tumor histopathological characteristics. We examined growth characteristics and the colony-forming ability of established cell lines in terms of their cell cycle parameters, expression of tumor markers (carcinoembryonic antigen; CEA, carbohydrated antigen 19-9; CA19-9, MUC-1 and c-kit) and the oncogene c-erbB2 by flow cytometer. Comparative genomic hybridization (CGH) analysis with specific gene probes was performed to detect changes in the gene copy numbers. Human origin of cell lines was confirmed by chromosomal analysis. Cells maintained differentiation characteristics of the original tumors. The doubling time of different cell lines varied from 30 to 96 h. All 5 cell lines formed colonies in the colony forming assays and expressed CEA, CA19-9, MUC-1 and the oncogene c-erbB2 and showed chromosomal aneuploidy. CGH analysis demonstrated gain of chromosomal region bearing SRC, RAB1, and PAP in all cell lines and hTERT in 4 cell lines. These newly established cell lines might serve as a useful model for studying the molecular pathogenesis of gallbladder cancer. Furthermore, they may serve as a model for testing new therapeutics against gallbladder cancer. These chromosomal aberrations and imbalances provide a starting point for molecular analyses of genomic regions and genes in gallbladder carcinogenesis.  相似文献   
996.
Enteropathy-type T-cell lymphoma (ETL) is an intraepithelial T-lymphocyte (T-IEL) tumor. The tumor cells are usually CD3+, CD4-, CD8+, and contain cytotoxic granule associated proteins. We report on a CD3-negative CD56-positive enteropathy-associated lymphoma (ETL). This is the first case report of CD3-negative, CD56-positive, CD94-negative, and CD161-positive ETL. ETL cells originate from intraepithelial T-lymphocytes of the intestine. CD3-negative intraepithelial lymphocytes are known as natural killer (NK)-IELs. The phenotype of NK-IELs is also CD3-negative, CD56-positive, CD94-negative, and CD161-positive, while most normal NK cells express CD56 and CD94. CD3-negative lymphoma cells in this report also expressed CD56 and CD161, but not CD94. Because Southern blotting analysis showed a rearrangement of T-cell receptor (TCR) Cbeta in this case, the tumor is classified as an ETL. Based on the findings, NK-IELs may originate from T-cells, not NK-cells.  相似文献   
997.
Dihydropyrazines (DHPs), which generate hydroxyl and carbon-centered radicals, cleaved DNA single-strand. It is new knowledge that DHPs were recently determined to produce 8-hydroxydeoxyguanosine. The remarkable increase in the DNA strand-cleavage activity upon the addition of Cu2+ suggests that the primary reactive species is carbon-centered radicals rather than the hydroxyl radical generated the initiation reaction. This proposal was in fair agreement with of the observed carbon-centered radical signal intensity, but an effect was not observed with the increase in the hydroxyl radical signal intensity.  相似文献   
998.
Stress-induced colonic functional changes have been investigated mainly under conditions involving physical stress, like in the restraint stress model. In this study, we established a new stress-induced defecation model involving the placement of Mongolian gerbils in a novel environment (novelty stress) and determined the effects of several drugs on novelty stress-induced fecal pellet output. When animals kept in groups were placed individually in small cages, the fecal pellet output markedly increased, although the upper intestinal transit measured by charcoal method was not changed. The concentration of plasma adrenocorticotropic hormone was moderately but significantly increased by the novelty stress. Drugs reportedly effective for stress-induced defecation, like alosetron hydrochloride, atropine sulfate, and trimebutine maleate, inhibited both the novelty stress-induced increase in fecal pellet output and spontaneous defecation. In contrast, TAK-637, a tachykinin NK1-receptor antagonist, and diazepam inhibited the novelty stress induced defecation but did not inhibit spontaneous defecation. The present study indicated that novelty stress increases fecal pellet output without affecting the upper intestinal transit; this model may be useful for evaluating the effects of drugs on stress-stimulated colonic motility.  相似文献   
999.
A 51-year-old man had been diagnosed with severe aplastic anemia (AA) at the age of 9 years. He was treated with occasional transfusions for the next 35 years. Following initiation of cyclosporin A (CsA), the patient became transfusion-independent at 44-years-old. Anemia improved after cessation of CsA and no therapy was required for the next 5 years. However, severe pancytopenia suddenly developed at the age of 51. Bone marrow aspiration revealed myelodysplastic syndrome (MDS) with der (1;7). The ineffectiveness of CsA for MDS led to resumed dependence on transfusion. This case suggests that the appearance of MDS clones might have contributed to transient hematological improvement. Bone marrow aspiration should be considered in patients with AA if unexpected hematological improvement appears.  相似文献   
1000.
A variety of medicines have been used for the treatment of inflammatory bowel disease. Antibacterial therapy has demonstrated promise by both improving symptoms and causing disease remission. The mechanism is unknown, but may be related to either eliminating a key pathogen, decreasing the number of bacterial secretory products or defective particles, a direct immunomodulating effect, or reducing secondary bacterial invasion. Historically, a large number of bacterial species have been suspected as being major contributors to the etiology of inflammatory bowel disease, including ulcerative colitis and Crohn's disease. Many trials of antibacterial agents have been carried out in inflammatory bowel disease. Recently, treatments have focused on Gram-negative anaerobes and mycobacteria. The present paper briefly reviews antimicrobial and antimycobacterial treatments in inflammatory bowel disease.  相似文献   
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