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71.
BACKGROUND: The aim of this study was to determine the activity of the combination of cisplatin, gemcitabine and 5-fluorouracil (5-FU) as therapy for metastatic or locally advanced inoperable pancreatic adenocarcinoma. PATIENTS AND METHODS: Patients with histologically proven advanced or metastatic pancreatic adenocarcinoma received first-line chemotherapy comprising cisplatin (20 mg/m2 on days 1, 8, 15, 22, 29 and 36), gemcitabine (1000 mg/m2 on days 1, 8, 29 and 36) and 5-FU (200 mg/m2 as continuous infusion on days 1-42) every 56 days. RESULTS: A total of 34 patients were studied. Eighty courses were administered (median two courses per patient). Among 32 patients evaluable for response, two patients had a complete response and four a partial response for an overall response rate of 19% (95% confidence interval 7% to 36%). Thirteen patients had stable disease (40%) and 13 progressed. Median progression-free survival was 4.7 months, median survival 9.0 months and 26% of patients achieved 1-year survival. Ten of 25 patients (40%) with pain at presentation had a sustained reduction of analgesic consumption. The principal grade 3/4 toxicities were neutropenia, thrombocytopenia, anaemia and mucositis, occurring in 24%, 21%, 9% and 3% of patients. CONCLUSION: This schedule seems well tolerated and active in pancreatic cancer and worthwhile of further evaluation.  相似文献   
72.
Tetrachloroethylene, an industrial halogenated solvent, shows several toxic effects. Also at hepatic level this substance can induce a damage but this effect is present only after high exposure, but such high levels have not been found in work environments. Using Wistar rats, we wanted to check whether the chronic administration of ethyl alcohol can modify the action of tetrachloroethylene. Tetrachloroethylene was administered by aerosol and alcohol at the concentration of 15% in drinking water. We observed an increase in plasma triglycerides, and evident histological alteration as a result of steatosis, in rats drinking alcohol as compared to a control group; the administration of tetrachloroethylene to rat drinkers of alcohol did not cause an increase in plasma triglycerides and steatosis as compared to rat drinkers of alcohol, but on the contrary we observed a decrease in alcohol-induced liver damage.  相似文献   
73.
The effect of exogenous L-propionyl carnitine on peroxidative injury was investigated on isolated working rat hearts. The addition of 190 microM hydrogen peroxide to the perfusion buffer caused a marked decrease in aortic flow, minute work and peak aortic pressure, and a release of intracellular enzymes. In the presence of L-propionyl carnitine the haemodynamic damage was significantly lower and enzyme leakage remarkably decreased. The protection was concentration-dependent and the whole structure of the molecule was required, since carnitine alone was found less effective and propionate had no effect. In the absence of hydrogen peroxide L-propionyl carnitine increased heart performance. The effect of L-propionyl carnitine on oxidative stress could account for the beneficial effect of this substance in different models of ischaemic injury. L-propionyl carnitine increases the cardiac performance and protects the rat heart from peroxidation through metabolic and antiperoxidative mechanisms.  相似文献   
74.
In 50 patients, 1 mCi 123I phenylpentadecanoic acid (IPPA) was injected at peak ergometric stress and 1500 frames were acquired (1 frame/s) with a high count rate gamma camera. Parametric images of rates of decrease and increase for different time intervals after stress were compared with coronary angiography and LV ventriculography, separately evaluating the 3 main coronary territories: 18/150 territories supplied by normal coronaries presented rather homogeneous regional clearing rates, whereas a gradual decrease in clearing rates towards the end of the territory (frequently with peripheral defects) was seen in all 87/150 territories with significant coronary narrowing. In local correspondence to clearing defects, initial IPPA accumulations could be observed with later onset of clearing between 10 and 25 min. 44/150 territories presented abnormal clearing rates, mostly with a patchy pattern, with normal coronary anatomy, but all except one had LV dysfunction and a clinical diagnosis of cardiomyopathy, diabetes mellitus or hypertensive disease. Twenty four of the 41 patients with CAD had, in correspondence to a prior myocardial infarction, minimum or missing metabolic activity frequently in circumscribed zones, partly separated by bridges of still viable tissue with preserved but reduced clearing rates.  相似文献   
75.
The opioid activity pattern of 8 dermorphin tetrapeptides, W-Tyr-D-MetO-Phe-Xaa-Y (W = H, H2N-C = (NH); Xaa = Gly, 2-aminoethanol, sarcosine; Y = NH2, NH-alkyl), was determined in guinea-pig ileum (GPI) preparations and in brain binding assays and compared with their antinociceptive potency in mice. Almost all modifications increased potency on the GPI test as well as the antinociceptive action of the parent H-Tyr-D-Ala-Phe-Gly-NH2. Dermorphin, H-Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2, and related tetrapeptide analogues show negligible K-binding activity and, like morphine, possess a higher affinity to mu- than delta-receptors. Nevertheless the correlation of analgesia with the effects on GPI and binding data separate the peptides from morphine. For example, in comparison with the opiate alkaloid H-Tyr-D-MetO-Phe-Gly-ol and H-Tyr-D-MetO-Phe-Gly-NH2 displayed a lower affinity for mu sites, a moderately higher potency on GPI but an exceptionally stronger analgesia, being respectively 350 and 1500 times as potent an analgesic as morphine. This may involve different subpopulations of opioid mu-receptors.  相似文献   
76.
77.
Thirty-nine patients with locally advanced breast cancer (T3b-4, N1-3 or inflammatory carcinoma) received 3 cycles of induction chemotherapy with estrogenic recruitment before surgery. The therapeutic regimen consisted of diethylstilbestrol (DES) orally on days 1-3, 5-Fluorouracil + Doxorubicin + Cyclophosphamide on day 4 q 21 days (DES-FAC). After surgery 6 additional cycles of chemotherapy (3 DES-FAC alternating with 3 DES-CMF with Methotrexate + F and C as in FAC) were administered. The objective response rate was 71.8% with 15.4% CR, and 56.4% PR; after surgery 36/39 (92.3%) patients were rendered disease-free. So far, 13 of 26 patients in stage IIIb have relapsed (9 of 13 with inflammatory carcinomas). Three-year survival and progression-free survival are 60% and 53.5%, respectively. Twenty-three of the 39 patients were subjected to serial tumor biopsies during the first DES-FAC regimen to allow for tumor-cell kinetic studies during DES and chemotherapy. A significant estrogenic recruitment occurred in 16 patients (69.6%), irrespective of estrogen-receptor status. At surgery, 3-4 weeks after induction chemotherapy, tumor proliferative activity was significantly depressed in comparison to basal values. These results indicate that breast cancer cells can be recruited in vivo with DES and that chemotherapy following estrogenic stimulation is effective and feasible with acceptable toxicity.  相似文献   
78.
Endothelin-1 (ET-1) is an amino peptide produced by endothelial cells with a potent vasoconstrictor activity; this effect is regulated by a release of other endogenous vasal factors. Recent studies have demonstrated that endothelin is capable of releasing from different tissues, and particularly from perfused organs such as spleen and kidney, many vasal factors and prostanoids. The present study investigates whether perfusion with a solution of endothelin-1 in rat isolated kidney can induce the release of histamine, another vasal factor (until now not investigated in relation with endothelin-1) and whether treatment with propionyl carnitine, a compound with vasoprotecting activity, inhibits this release. This research demonstrates that histamine released by rat kidney perfused with endothelin is lowered if previously treated with propionyl carnitine. This effect of propionyl carnitine can be considered to be another important factor in a complex mechanism involved in its vasoprotective and cardiovascular action.  相似文献   
79.
A method is presented for measuring the volume of the oedema induced by intraplantar infection of polymyxin B, a polyenic antibiotic, in the hind paw of the rat. Peak values of the oedema reached the maximum within 30 min to 1 h after injecting the drug and decreased with time until the 24th h, when it had almost disappeared. The phlogogenic effect of polymyxin B seems to be related to that induced by serotonin and histamine, rather than to the reaction provoked by carrageenin or prostaglandins. The oedema was inhibited by pretreating the animals p.o. with both steroidal and non-steroidal antiinflammatory agents. The inhibitory effect of antiinflammatory drugs was found to be dose-dependent.  相似文献   
80.
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