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991.
BACKGROUND: There are few studies about dietary supplement use and nutrient intake from these products in Japan. The purpose of this study was to clarify (1) the prevalence of dietary supplement use, (2) the characteristics of dietary supplement users, (3) nutrient intake from dietary supplements, and (4) the existence of dietary supplement users who took excessive nutrients from these products. METHODS: To collect the information on dietary supplement use in the previous year and nutrient intake from these products, we conducted a self-administered dietary supplement frequency questionnaire. The subjects were 2,259 people aged 40-82 years. Dietary supplements were grouped into 8 major categories. A dietary supplement database was developed to estimate nutrient intake from these products. Excess users were defined as people who consumed more nutrient than the tolerable upper intake level of the Dietary Reference Intakes for Japanese. RESULTS: In the previous year, 55 % of males and 61 % of females consumed dietary supplements. Dietary supplement use was especially prevalent in females, subjects who felt unhealthy, and subjects who were more careful of maintaining an appropriate weight, though the association was affected by the frequency of dietary supplement use. The most common dietary supplements were drink type in males and vitamins in females. Some nutrient values obtained from dietary supplements were higher than those from food. Excess users were found for intake of vitamin A, B(6), K, niacin, iron, and magnesium. CONCLUSIONS: It is important to clarify dietary supplement use and to estimate nutrient intake from these products.  相似文献   
992.
993.
This study is the first to report on the use of x-ray photoelectron spectroscopy (XPS or ESCA) for studying the surface films (less than 10 nm thick) of aged amalgams. The concentrations and electron binding energies of the elements on the surfaces of four different amalgams aged for 20 min, one day, seven days, and 30 days were determined quantitatively. For comparison, the bulk compositions of the amalgams aged for seven days were also determined after removal of approximately 5 nm of material from the surface by argon-ion-sputtering. The XPS data revealed that the surface films of aged zinc-containing amalgams were not a simple oxide but were primarily composed of a (hydrated) tin and zinc oxy-hydroxide, whereas, in the zinc-free amalgams, the surface films were primarily a tin oxide. The concentration of mercury in this thin surface film after aging was depleted. This suggests that tin and/or zinc preferentially diffused to the surface and combined with oxygen, forming a surface film and diluting the mercury concentration in the surface. Another probable explanation for the depleted mercury is that a minimal amount of mercury in the surface film evaporated during the aging.  相似文献   
994.
Plasma cross-circulation that resembles clinical plasma exchange was carried out in rats with galactosamine (GalN)-treated hepatic failure to investigate its effect on the damaged liver function. Twenty-four hours after the injection of GalN, plasma cross-circulation was performed at a plasma flow rate of 0.1 ml/min for 6 h. At 48 h after the injection of GalN, survival was obtained in 6 of 8 GalN-injected rats treated with plasma cross-circulation as compared with 4 of 10 GalN-injected rats treated with sham circulation. State 3 oxygen consumption and ATP synthesis (mitochondrial respiratory function) and ATP, ADP, and total adenine nucleotide contents in the liver were significantly higher in the former group than in the latter group at that period, as determined by sacrificing the surviving animals. Although the survival rate was not significantly improved, evidence suggests that plasma cross-circulation enhanced mitochondrial phosphorylative activity and produced an augmented high-energy state of the liver, which had been markedly reduced by GalN administration. An efficient removal of toxic metabolites as well as an influx of a large amount of fresh plasma by plasma cross-circulation would be beneficial for the regenerative process of the necrosing liver tissues.  相似文献   
995.
A reproducible and sensitive rubella plaque neutralization test was established utilizing a Japanese, live, attenuated vaccine strain (KRT-Kitasato, GMK 4/RT 36/RK 1) in a rabbit kidney cell line (RK-13). Rubella strain, cell line derivation, addition of complement and temperature of incubation were all critical to the efficiency of plaque formation. Two hundred sera from 25 children collected longitudinally following rubella vaccination with HPV77DE5 were tested for rubella antibody by three different assays: 1) plaque neutralization, 2) hemagglutination inhibition, and 3) enzyme linked immunoadsorbent assay by commercial kit. Plaque neutralization antibody appeared more slowly after immunization than that determined by hemagglutination inhibition, but persisted in all 22 successfully immunized children over a five to seven year period. The same 22 children had a rise in hemaggulutination inhibition antibody, but lost detectable antibody five to seven years after vaccination. Only 21 children seroconverted by enzyme immunoadsorbent assay. Nine of these lost detectable antibody by five years.  相似文献   
996.
Bilateral adrenalectomy markedly aggravated gastric ulcers in rats induced by 5 or 20 mg/kg of indomethacin. The degree of aggravation was much the same in experiments done 1 and 14 days after operation. Pretreatment with prednisolone 10 mg/kg or cortisone acetate 10 mg/kg given subcutaneously significantly suppressed the aggravated ulceration in response to 20 mg/kg of indomethacin in these adrenalectomized rats. Desoxycorticosterone acetate 10 mg/kg, however, had no effect on the aggravation of indomethacin-induced ulcers. Epinephrine 0.1 or 1 mg/kg given subcutaneously markedly suppressed the indomethacin-induced ulcers in adrenalectomized rats. Removal of the adrenal medulla alone did not appreciably influence the development of indomethacin-induced ulcers. These results indicate that the adrenal cortex, particularly the area containing glucocorticoids, plays an important role in suppression of the noxious effect of indomethacin on the rat gastric mucosa.  相似文献   
997.
998.
Through the extensive investigation of new mitomycin C (MMC) derivatives, several compounds with disulfide at N-7 were found to show activities superior to MMC against murine Sarcoma 180 solid tumor. Among them, 7-N-[[2-[[2-(gamma-L-glutamylamino)ethyl]dithio]ethyl]]- mitomycin C (KW-2149) was selected for further evaluation of antitumor activity and toxicity in mice. KW-2149 exhibited activity superior to MMC in increasing survival of i.p. inoculated P388 leukemia-, M5076 sarcoma-, and B16 melanoma-bearing mice. KW-2149 administered i.v. also exhibited superior activity in inhibiting the growth of s.c. inoculated P388 leukemia, M5076 sarcoma, and colon 26 adenocarcinoma and in increasing survival of i.v. inoculated P388 leukemia- and M5076 sarcoma-bearing mice. Furthermore, KW-2149 remarkably increased the life span of MMC-resistant P388 leukemia- and L1210 leukemia-bearing mice. KW-2149 and MMC inhibited the growth of human tumors inoculated into nude mice. The activity of KW-2149 was prominent in human lung carcinoma Lu-65 and Lu-99, bladder carcinoma T24, and epidermoid carcinoma A431. KW-2149 was comparable to MMC in decreasing the number of WBC in the peripheral blood, and the thrombopenia induced by KW-2149 was mild and recovery was rapid. The in vitro anticellular spectrum of KW-2149 against 23 human tumor cell lines was similar to that of MMC. However, KW-2149 inhibited the growth of the cell lines at concentrations of 10- to 100-fold lower than MMC and showed efficient cytotoxicity against MMC-insensitive tumor cell lines. These included lung epidermoid carcinoma Calu-1, stomach carcinoma MKN-28, colon adenocarcinoma DLD-1, colon adenocarcinoma LoVo, bladder carcinoma HT-1197, sarcoma G-292, and melanoma SK-MEL-28 cells. These results indicate that KW-2149 bears interesting characteristics as a new anticancer drug and warrants further development.  相似文献   
999.
The growth-suppressive activity of the retinoblastoma (RB) protein is suggested to be regulated by phosphorylation. In studies on the kinase that phosphorylates the RB proteins, we have previously found that RB proteins can be phosphorylated by purified cdc2 kinase. In this study, we noted that RB proteins immunoprecipitated from human cell lysates are weakly phosphorylated in the absence of purified cdc2 kinase. Immunoblot analysis showed the presence of p34cdc2 in the immunoprecipitates with anti-RB monoclonal antibody. In addition, the coprecipitated kinase was found to have the same substrate specificity as cdc2 kinase. The associated kinase activity was particularly high in cells arrested in G1/S and S phase by aphidicolin. Furthermore, RB proteins were shown to be phosphorylated in nuclear extracts by some endogenous cdc2-like kinase(s). These results suggest that cdc2-like kinase is the main kinase for phosphorylation of RB proteins in vivo.  相似文献   
1000.
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