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1.
The methanolic fraction of P. indica root extract was found to possess significant antiulcer activity in different experimental animal models. In preventive antiulcer tests, significant protective actions in acetylsalicylic acid, serotonin and indomethacin-induced gastric lesions were observed in experimental rats. The extract also afforded significant protection to chemically-induced duodenal lesion in guineapigs. Significant enhancement of healing process in acetic acid-induced chronic gastric lesions were also observed in the extract-treated animals. 相似文献
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Sutapa Mukherjee G.P. Talwar 《American journal of reproductive immunology (New York, N.Y. : 1989)》1996,35(1):51-56
PROBLEM: Development of an orally administered abortifacient. METHODS: Subjects were female Wistar rats, weighting 150 to 200 g at the time of experiments. Praneem (a purified extract of neem Azadirachta indica) at a dose of 0.6 ml was given orally from day 8 to 10 after confirming presence and number of implants surgically on day 7 of pregnancy. The animals were examined again under anesthesia on day 15 of pregnancy to check the number of developing embryos. Controls received an equivalent regime of peanut oil. The number and size of implants were counted five days after treatment. RESULTS: Complete resorption of embryos was observed on day 15 of pregnancy in every animal treated with Praneem in contrast to normally developing embryos in rats given peanut oil. In repeat batch experiments, it was established that the effect of the treatment was reversible and animals regained fertility in cycles subsequent to treatment with Praneem. Cytokines of TH1 type, i.e., gamma interferon and TNF, were raised on administration of Praneem, which may be the probable cause of pregnancy termination. CONCLUSIONS: Praneem on oral adminstration can cause termination of pregnancy in rodents, and the action is probably mediated by TH1 cytokines. 相似文献
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A novel approach for immunocontraception by intervention of local cell mediated immunity in the reproductive system by using single intrauterine application of neem oil has been described earlier. The reversible block in fertility was reported to last for 107–180 days in female Wistar rats (Upadhyay et al., 1990. Antifertility effects of neem oil by single intrauterine administration: A novel method of contraception. Proceedings Of The Royal Society Of London B 242, 175–180) and 7–11 months in monkeys (Upadhyay et al., 1994. Long term contraceptive effects of intrauterine neem treatment (IUNT) in bonnet monkeys: An alternative to intrauterine contraceptive devices. Contraception 49, 161–167). The present study, describes the identification and characterization of the biologically active fraction from neem seeds (Azadirachta indica A. Juss. Family Meliaceae), responsible for the above activity in adult female Wistar rats. Initial studies with the mechanically extracted oil and solvent extracts of neem seeds have revealed that the antifertility activity was present in constituents of low to intermediate polarity. A hexane extract of neem seeds was reported to be biologically active (Garg et al., 1994. Comparison of extraction procedures on the immunocontraceptive activity of neem seed extracts. Journal of Ethnopharmacology 22, 87–92). Subsequently, hexane extract was sequentially fractionated through the last active fraction using various separation techniques and tested for antifertility activity at each step. Preparative HPLC was used for isolating individual components of the active fraction in quantities, sufficient for characterization. An analytical HPLC method was developed for standardization of the fraction. The active fraction was identified to be a mixture of six components, which comprises of saturated, mono and di-unsaturated free fatty acids and their methyl esters. Dose response study was performed with the last active fractions. The antifertility activity with the active fraction was reversible in nature and it was completely active until 5% concentration. There was no systemic toxic effect following the administration of the active fraction. This study, for the first time, proposes an active fraction from neem seeds, responsible for long term and reversible blocking of fertility after a single intrauterine administration with high efficacy. 相似文献
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目的 对山莴苣(Lactucaindica L.)染色体核型等进行研究,为该种鉴定、起源、演化、良种培育等的深入研究提供必要的细胞学资料。方法 采用常规制片方法 ,结合显微摄影技术对染色体进行检测分析。结果 山莴苣体细胞染色体数目2n=18;核型公式是K(2n)=18=4m+14sm,染色体相对长度组成为2n=18=8M2+8M1+2S,属于“3A”型。全组染色体总长是60.03μm,长臂总长40.33μm,核型不对称系数为67.18%。染色体总体积113.05μm3。结论 山莴苣染色体的数量、形态清晰,可为进一步的深入研究打下基础。 相似文献
7.
Carolina B. Wandscheer Jonny E. Duque Mario A.N. da Silva Yoshiyasu Fukuyama Jonathan L. Wohlke Juliana Adelmann Jos D. Fontana 《Toxicon》2004,44(8):829-835
Ethanolic extracts from the kernels of ripe fruits from the Indian Lilac Melia azedarach and from the well-known Neem tree, Azadirachta indica were assayed against larvae of Aedes aegypti, the mosquito vector of dengue fever. The lethality bioassays were carried out according to the recommendations of the World Health Organization. Extracts were tested at doses ranging from 0.0033 to 0.05 g% in an aqueous medium for 24 and 48 h, at 25 or 30 °C, with or without feeding of the larvae. LC50, LC95 and LC99 were determined. Both seed extracts proved lethal for third to fourth instar larvae. Non-fed A. aegypti larvae were more susceptible to Azadirachta extracts at both temperatures. Under a more realistic environmental situation, namely with fed larvae at 25 °C, the death rates caused by the Melia extract were higher, although at 30 °C the extract of Azadirachta had an even higher lethality. Inter allia, the LC50 values for the crude extracts of these two members of the Meliaceae ranged from 0.017 to 0.034 g% while the LC99 values ranged from 0.133 to 0.189 g%. Since no downstream processing was undertaken to purify the active agents in the extracts, our findings seem very promising, suggesting that it may be possible to increase the larvicidal activity further by improving the extraction and the fractionation of the crude limonoids, for instance removing the co-extracted natural fats. 相似文献
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Manoj Singh Pramesh Chandra Lakhera Balwinder Singh Gohar Taj 《Food and Agricultural Immunology》2013,24(2):203-216
This article aims to characterise and localise the glycosyl moieties of teliospore wall of Tilletia indica a quarantined fungal pathogens by biochemical and immunological approaches. Chemical enzyme modifier studies, followed by determination of structural configuration using phase contrast and SEM after periodate treatment, showed antigenic entities are glycoprotein in nature. Further characterisation using sodium dodecyl sulphate-polyacrylamide gel electrophroesis (SDS-PAGE) glycoprotein staining and western blotting using anti-teliospore antibodies showed two common proteins of molecular weight 28 and 40 kDa, which is also suggestive of glycoprotein nature of antigenic entities of teliospore wall. To study the binding patterns and localisation of glycosyl moieties on the teliospore walls, fluorescein isothiocyanate (FITC) labelled lectins [Wheat Germ Agglutinin (WGA) and Concanavilin A (Con A)] and anti-teliospore antibodies were used. The patterns of WGA and anti-teliospore antibodies binding with teliospore wall are almost similar and hence it is quite reasonable to suggest that immunodominant glycosyl entities of teliospore wall are acetylglucosamine in nature. 相似文献
9.
Objective To study the ent-kaurane diterpenoids from Rabdosia rubescens. Methods The compounds were isolated by chromatographies and their structures were identified by spectral analyses. Results Four compounds were isolated, and they were identified as bisrubescensin E (1), 2α,3α,24-trihydroxyurs-12-en-28-oic acid (2), 2α,3α,24-trihydroxyurs-12,20-(30)-dien-28-oic acid (3), and 6,7-dihydroxycoumarin (4). Conclusion Compound 1 is a new asymmetric ent-kauranoid dimer. Compound 2 is isolated from the plant for the first time. Compounds 3 and 4 are isolated from the plants of Rabdosia (Bl.) Hassk for the first time. 相似文献
10.
对印度雕蚀菌在三带喙库蚊幼虫体内的发育进行了观察,表明1龄幼虫可被真菌所感染,菌体在蚊幼虫血腔内随虫体长大和变态而产生大量孢子囊,即完成其孢子增殖阶段,不再继续发育。孢子囊由死亡腐烂的蚊幼虫体释放于水中,在34℃下经8—12h的发育,囊内游动孢子成熟,于适宜条件下经1/2—1h可全部从囊中逸出。游动孢子在水中极为活跃,1h后活力下降,它为感染剑水蚤宿主的感染期。 相似文献