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排序方式: 共有1030条查询结果,搜索用时 15 毫秒
41.
The synthesis of drugs, drug intermediates, and flavor and amide compounds by PLE (pig liver esterase) and PPL (pig pancreatic
lipase) carried out in this laboratory has been reviewed and their selectivity in the synthesis of compounds compared. A new
method of synthesis of paracetamol, a common analgesic drug, using PLE and PPL to overcome the complicated steps for chemical
synthesis starting from p-aminophenol, which is an unstable compound, has been discussed. A new route for enzymatic transesterification of geraniol
has been efficiently carried out by PLE, and the result was better than PPL.
An erratum to this article can be found at 相似文献
42.
OBJECTIVE: To investigate whether the ratio of fetal cells in the maternal circulation differs before and after the blood passes through the maternal lung. METHODS: We performed polymerase chain reaction-based Y-sequence analysis of DNA derived from antecubital vein blood obtained before and 2 hours after cesarean delivery, and from uterine vein blood obtained during cesarean of 14 women carrying male fetuses. RESULTS: Fetal DNA was detected in 17 tested specimens and, as estimated by comparison with parallel dilution series, the fetal-maternal DNA ratio was 1:10(5) to 1:10(6). However, there was no significant difference in the amount of Y-chromosomal DNA detectable between uterine vein blood and peripheral blood after polymerase chain reaction and Southern hybridization. In DNA derived from peripheral blood after delivery, the intensity of Y-specific fetal DNA sequences was also not significantly increased. CONCLUSION: Our results argue against the often-stated hypothesis of different ratios of fetal to maternal DNA in the uterine vein versus peripheral blood, and indicate that even delivery does not seem to increase the flow of fetal cells into the maternal circulation. 相似文献
43.
44.
Approximately 15-20% of error in the diagnosis of acute appendicitis argues for new diagnostic methods. In recent years it has been proposed that Computed Tomography be used in the diagnosis of acute appendicitis with high sensitivity and specificity. In our study, the effect of Computed Tomography on the diagnosis of acute appendicitis and on negative appendectomy was investigated on patients with suspected acute appendicitis. In the last 18 months, spiral Computed Tomography without contrast material has been used for 65 patients. The history, physical findings, laboratory results and Computed Tomography images of patients were compared and the final decision to operate was always made by an attending surgeon. The results of Computed Tomography have been correlated with the reports of pathology and operation findings. Other patients who have not been operated on have been followed up clinically. Correlating Computed Tomography results with operation findings revealed; 42 true positive, 3 false positive, 17 true negative and 3 false negative results. The sensitivity and specificity of CT have been found to be 93.3% and 85% respectively. Forty-eight out of 65 patients have been operated on for acute appendicitis and the negative appendectomy rate has been calculated as 6.25%. As a consequence, it was thought that in the diagnosis of acute appendicitis the use of Computed Tomography could decrease the negative appendectomy rate when used together with clinical follow-up. 相似文献
45.
Urman B Mercan R Alatas C Balaban B Isiklar A Nuhoglu A 《Journal of assisted reproduction and genetics》2000,17(10):586-590
Purpose: The aim was to evaluate the effect of aspirin on pregnancy and implantation rates in an unselected group of patients undergoing intracytoplasmic sperm injection (ICSI).
Methods: Two hundred and seventy-nine patients were randomized to receive 80 mg of aspirin (n = 139) or no treatment (r = 136) starting from the first day of controlled ovarian hyperstimulation.
Results: Duration of stimulation, gonadotropin consumption, peak estradiol, number of oocytes retrieved, fertilization rate, cleavage rate, and number of embryos transferred were similar in the two groups. Implantation and clinical pregnancy rates were 15.6% and 39.6% versus 15.1% and 43.4% in aspirin treated and untreated groups, respectively (P > 0.05).
Conclusions: Low-dose aspirin administration does not improve implantation and pregnancy rates in an unselected group of patients undergoing ICSI. 相似文献
46.
Sarkar M Gangopadhyay P Basak B Chakrabarty K Banerji J Adhikary P Chatterjee A 《Contraception》2000,62(5):271-274
To study the antifertility effect of an extract (alcoholic) of the leaf-stalk of Piper betle Linn., one set of experiments with two different doses in Swiss male albino mice were evaluated. Initially, 500 mg of the leaf-stalk extractive for 30 days and then 1000 mg for next 30 days/animal/day/kg body weight were administered orally. The extract reduced fertility to 0% within 60 days. Suppression of cauda epididymal sperm count and motility (p <0.05) was observed. Biochemical parameters did not show any marked alterations in testosterone content in serum nor 17beta-hydroxysteroid dehydrogenase (17beta-HSD) activity in testes although fructose content in seminal vesicles was reduced as are the weights of reproductive organs. The cholesterol content in testes increased, although not appreciably. After cessation of drug (plant extract) treatment, the altered parameters recovered. Results suggest that the contraceptive effect of the extract of leaf-stalk of Piper betle Linn. is mainly on the maturation process of spermatozoa in epididymides without influencing hystemic hormonal profiles. Withdrawal of the extract restored all altered parameters including organ weights and fertility after 60 days. 相似文献
47.
J. Zaloudik S. Basak M. Nesbit D. W. Speicher W. H. Wunner E. Miller C. Ernst-Grotkowski R. Kennedy L. P. Bergsagel T. Koido D. Herlyn 《British journal of cancer》1997,76(7):909-916
The CO17-1A/GA733 antigen is associated with human carcinomas and some normal epithelial tissues. This antigen has shown promise as a target in approaches to passive and active immunotherapy of colorectal cancer. The relevance of animal models for studies of immunotherapy targeting this antigen in patients is dependent on the expression of the antigen on normal animal tissues. Immunohistoperoxidase staining with polyclonal rabbit antibodies to the human antigen revealed the human homologue on normal small intestine, colon and liver of mice, rats and non-human primates, whereas mouse monoclonal antibodies to the CO17-1A or GA733 epitopes on the human antigen did not detect the antigen. Polyclonal rabbit antibodies, elicited by the murine antigen homologue derived from recombinant baculovirus-infected insect cells, immunoprecipitated the antigen from mouse small intestine, colon, stomach, kidney and lung. The isolated recombinant murine protein bound polyclonal, but not monoclonal, antibodies to the human CO17-1A/GA733 antigen, and recombinant human antigen bound polyclonal antibodies elicited by the murine antigen homologue. Thus, the antigen homologue expressed by animal tissues is similar, but not identical, to the human antigen. These results have important implications for experimental active and passive immunotherapy targeting the CO17-1A/GA733 antigen. 相似文献
48.
Structure and stereochemistry of nardostachysin, a new terpenoid ester constituent of the rhizomes of Nardostachys jatamansi 总被引:1,自引:0,他引:1
Chatterjee A Basak B Saha M Dutta U Mukhopadhyay C Banerji J Konda Y Harigaya Y 《Journal of natural products》2000,63(11):1531-1533
The structure and stereochemistry of a new terpenoid ester, nardostachysin (1), isolated from the rhizomes of Nardostachys jatamansi, were established as the 7',8'-dihydroxy-4'-methylene hexahydrocyclopenta[c]pyran-1'-one-8'-methyl ester of 7, 9-guaiadien-14-oic acid, by spectral and chemical studies. 相似文献
49.
50.
Vitamin D3, having gained scientific interest for so long because of its role in mineral homeostasis, has now received great importance as a possible antitumor agent. This study was undertaken in an attempt to visualize the possible anticlastogenic potential of the vitamin in an ascitic mouse lymphoma model namely, Dalton's lymphoma. Frequencies of structural type chromosomal aberrations, sister chromatid exchanges and micronucleus assays have been chosen as the genotoxic endpoints in the proposed investigation. All these cytogenetic markers have been found to be markedly elevated during the progression of lymphoma in bone marrow cells. Vitamin D3 effectively suppressed the frequencies of chromosomal aberrations and sister chromatid exchanges in the lymphoma-bearing mice during the entire phase of tumor growth that significantly coupled with almost two-fold increase in survival time (37 +/- 2 and 68 +/- 2 days in lymphoma controls and vitamin D3-treated lymphoma-bearing mice, respectively), thus substantiating the antineoplastic efficacy of this secosteroid. The outcome of this study also is clearly reflected in the depletion of circulating (serum) vitamin D3 levels in the lymphoma control mice compared with normal (vehicle) controls while a still higher level was maintained in the VD3-treated lymphoma mice. This anticlastogenic property of the vitamin has so far been neglected and this is the first attempt to unravel the vitamin D3's effect in combating tumor development in vivo by limiting the frequencies of chromosomal aberrations, sister chromatid exchanges and micronuclei at least in transplantable murine model studied herein. 相似文献