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D J Rosen M D Fejgin R Rabinowitz R H Regev Y Beyth 《Journal of perinatal medicine》1991,19(3):173-176
Indomethacin has been used in twins with polyhydramnios to decrease amniotic fluid volume. Under therapy, a marked reduction of both fetuses' urine production has been demonstrated within 24 hours concomitant with maternal symptomatic relief. Discontinuation of therapy was associated with a rapid increase in fetal urine production. The clinical observation indicates that the benefit of indomethacin in prolonging such pregnancies is most probably the result of relief of polyhydramnios through decreased fetal urine production. 相似文献
3.
Einat Rabinovitch Dror Harats Pnina Yaron Tamar Luvish Merav Lidar Ron Kedem Aviv Shaish Issahar Ben-Dov Avi Livneh 《Annals of allergy, asthma & immunology》2007,99(6):517-521
BACKGROUND: Asthma is an inflammatory airway disease caused by interaction between susceptibility genes and diverse environmental factors. In Israel, asthma seems to be familial and more severe in patients of Iraqi Jewish descent. On the other hand, asthma is less frequent in individuals with familial Mediterranean fever, an autoinflammatory disease prevalent in the Iraqi Jewish community and linked to mutations in the familial Mediterranean fever gene, designated MEFV. OBJECTIVES: To explore a possible role for mutated MEFV in the reduced susceptibility to asthma and to determine its expression in Israeli subjects of Iraqi origins. METHODS: Using a case-control approach, we studied the presence of the 3 most common MEFV mutations (M694V, V726A, and E148Q) in DNA samples from 75 patients with asthma and 45 asymptomatic first-degree relatives, all of Iraqi Jewish origin. The severity of asthma was evaluated using a published severity score. RESULTS: Eleven patients with asthma and 14 of their relatives carried 1 or 2 mutations in the MEFV gene, a carrier rate significantly lower in patients with asthma than in their first-degree relatives and in ethnically matched healthy individuals (P < .03 and P < .003, respectively). Carriers of MEFV mutations had less severe disease, compared with noncarriers (P < .002). CONCLUSION: These findings suggest that MEFV mutations may have a protective effect in the pathogenesis of asthma. 相似文献
4.
George J Barshack I Keren P Gazit A Levitzki A Keren G Roth A 《Experimental and molecular pathology》2005,78(3):233-238
BACKGROUND: Inflammation has been shown to play an important role in promoting the response to arterial injury and proinflammatory cytokines, such as tumor necrosis factor (TNF) alpha, are candidate mediators. AG-556 is a tyrosine kinase inhibitor proven to be effective in a model of multiple sclerosis-like syndrome in mice due to its immunomodulating effect. In the current study, we investigated the effect of the tyrphostin AG-556 on neointimal thickening and cytokine profile in a model of arterial injury in the mouse. METHODS: Injury was induced by external cuff placement on the left femoral artery of wild-type C57BL/6 mice. AG-556 dissolved in DMSO was injected intraperitoneally daily to the injured mice in a dosage of 2 mg/mouse. Control mice received DMSO injections. Histological analysis was carried out to assess neointimal formation. Splenocytes were cultured in the absence and presence of a mitogen for evaluation of thymidine incorporation and cytokine production. RESULTS: AG-556 treatment significantly attenuated intimal thickening (43,000+/-17,000 microm2; n=11) when compared to DMSO administration (286,000+/-127,000 microm2; n=10; P<0.05). Basal interferon-gamma production by splenocytes from AG-556-treated mice was increased by approximately 20-fold in comparison with levels in DMSO-treated animals, whereas Con-A induced secretion of the cytokine was similar between both groups. Levels of TNF-alpha, IL-4 and IL-10 in the culture supernatant from treated and non-treated animals did not differ significantly. CONCLUSION: The tyrosine kinase inhibitor AG-556 may have a role in the reduction of intimal thickening. The effect could be mediated via an immune modulating effect involving a significant increase in the smooth muscle cell inhibitory cytokine IFN-gamma. 相似文献
5.
The SRY gene on the short arm of the Y chromosome is necessary for male development. Without SRY, patients with 46,XY karyotype develop as females, fail to achieve normal puberty and have dysgenic gonads and a high incidence of gonadoblastoma. Here we report a female fetus, aborted at 17 weeks of pregnancy, with a non-mosaic 46,X,del(Y)(p11.2).ish del(Y)(SRY-) karyotype diagnosed by classical cytogenetics and fluorescence in situ hybridization (FISH). Ovarian tissue was full of oocytes and mitotic figures. FISH studies of ovarian tissues with X and Y centromere probes revealed extensive sex chromosome mosaicism, manifested by loss of the Y chromosome and polysomy of the X chromosome. We propose that X chromosome polysomy is a post-zygotic event that arises to facilitate gonadal differentiation in the absence of all factors necessary for normal gonadal development. 相似文献
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Efficient induction and selection of chloroplast-encoded antibiotic-resistant mutants in Nicotiana 总被引:3,自引:0,他引:3 下载免费PDF全文
Fluhr R Aviv D Galun E Edelman M 《Proceedings of the National Academy of Sciences of the United States of America》1985,82(5):1485-1489
A high rate of plastome-encoded mutations was induced in Nicotiana by exposing seeds to N-nitroso-N-methylurea. Seeds then were subjected to nutritional and in vitro selection procedures for systematic isolation of plastome-dependent antibiotic-resistant plants. Multiple flowering lines resistant to streptomycin, spectinomycin, lincomycin, or chloramphenicol were obtained. A detailed analysis of the streptomycin-resistant lines is presented. Sexual hybridization, cybrid formation following protoplast fusion, and in organello protein synthesis were used to rigorously assign the mutations to the chloroplast genome. The efficient rates of mutagenesis combined with the in vitro mass-screening procedures described here should facilitate investigation of fundamental aspects of chloroplast genetics in higher plants. 相似文献
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9.
Plant cells were entrapped by mixing suspended MENTHA cells with linear, water soluble polyacrylamide-hydrazide chains followed by the stoichiometric addition of glyoxal as the cross linking agent (PAAH-G entrapment). In parallel, some cells were entrapped in calcium-alginate beads, as previously described. The capability of both immobilized cell systems to reduce monoterpenes was compared with freely suspended MENTHA cells. Entrapment by either alginate or PAAH-G did not impair cell vitality, as observed by fluorescein diacetate staining. Biotransformation of (-) menthone to (+) neomenthol by M-cells and of (+) pulegone to (+) isomenthone by P-cells indicated that the transformation efficiency of the cells entrapped in PAAH-G is as high as that of freely suspended cells. Moreover, the distribution of both precursor and product in the medium versus their content in the cells (or cells contained in gel-beads) showed that less monoterpenes were retained in cells entrapped in PAAH-G, as compared to the freely suspended cells. Thus prolonged incubation (e.g. 24 hr), which usually results in appreciable loss of monoterpenes from the chloroform extract of freely-suspended-cells, caused considerably less loss from the PAAH-G entrapped-cells. In a preliminary test it was shown that PAAH-G entrapped cells were capable to perform three, consecutive, batch-type monoterpene biotransformations, without significant decrease of transformation capability. The capability to immobilize living plant cells within this synthetic chemically crosslinked gel system, combined with the favourable beads/ free-medium ratio of monoterpene distribution, point towards a potential development of a continuous biotransformation process carried out by plant-cells entrapped in this system. 相似文献
10.
Previous results indicated that all tested cell suspension lines derived from various MENTHA chemotypes were capable to biotransform (-) menthone to (+)-neomentol but only some of these lines converted (+)-pulegone to (+)-isomenthone. In order to quest whether only the natural secondary metabolites or also other compounds with similarities to pulegone are biohydrogenated by MENTHA cell suspensions, we incubated such suspensions with 5 unsaturated alpha-beta; ketones. No conversion was detected when mesityl oxide, trans-6-tert. butyl pulegone or 3-isopropylidine-9-methyl-decalone-2 were incubated with MENTHA cells, while saturation of the alpha-beta double bond of 2-isopropylidine cyclohexanone and of trans-6-methyl pulegone was observed in suspensions of those cell lines which are capable of pulegone transformation. Suspensions of MENTHA cell lines which were incapable to hydrogenate pulegone did not biotransform the two latter pulegone analogues. 相似文献