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排序方式: 共有1266条查询结果,搜索用时 15 毫秒
1.
T. A. Fedotcheva N. L. Shimanovskii A. I. Senderovich N. S. Chermnykh A. V. Semeikin V. M. Rzheznikov L. E. Golubovskaya G. S. Grinenko V. V. Banin P. V. Sergeev 《Pharmaceutical Chemistry Journal》2007,41(7):345-349
The hormonal compound with the highest cytostatic activity against MCF-7 tumor cells (human breast cancer, BC) and the lowest
activity against normal cells (rat skin fibroblasts) was sought among gestagens, androstenes, and antiestrogencytostatics.
It was found that antiestrogencytostatics and androstenes had the highest cytostatic activity against tumor cells whereas
gestagens and antiestrogencytostatics were least active against fibroblasts. Studies of the activity of the hormonal compounds
in combination with doxorubicin on the viability of MCF-7 and rat skin fibroblasts found that all investigated compounds with
the exception of dehydroepiandrosterone (DHEA) intensify the cytostatic activity of doxorubicin against tumor cells, the greatest
effect seen for antiestrogencytostatics. A chemoprotective effect of androstenes on normal cells was noted.
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Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 7, pp. 3–7, July, 2007. 相似文献
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M. S. Tverskaya V. V. Karpova A. O. Virganskii V. V. Banin L. A. Tsareva I. Zh. Satylganov R. V. Rogulenko E. I. Tikhvinskaya M. A. Chumakova I. G. Saganelidze 《Bulletin of experimental biology and medicine》1992,113(3):430-433
N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. S. Savel'ev.) Translated from Byulleten' Ékperimental'noi Biologii i Meditsiny, Vol. 113, No. 3, pp. 327–329, March, 1992. 相似文献
4.
Modified vaccinia virus Ankara (MVA) is a highly attenuated strain of vaccinia virus, which propagates efficiently in chicken embryo fibroblasts but fails to complete its growth cycle in many types of mammalian cells. We constructed a recombinant virus MVA/EK5, which has a chimeric gene encoding for the extracellular domain of the HIV envelope protein fused to the cytoplasmic and transmembrane domain of the B5R protein of vaccinia virus. The fused HIV envelope antigen was expressed in the African green monkey kidney BS-C-1 cells infected with the recombinant virus. This virus, which had been grown in chicken embryo fibroblasts, induced in rabbits antibodies against the HIV envelope antigen, in addition to those against poxvirus. 相似文献
5.
Neurons have ion channels that are directly gated by voltage, ligands and temperature but not by light. Using structure-based design, we have developed a new chemical gate that confers light sensitivity to an ion channel. The gate includes a functional group for selective conjugation to an engineered K(+) channel, a pore blocker and a photoisomerizable azobenzene. Long-wavelength light drives the azobenzene moiety into its extended trans configuration, allowing the blocker to reach the pore. Short-wavelength light generates the shorter cis configuration, retracting the blocker and allowing conduction. Exogenous expression of these channels in rat hippocampal neurons, followed by chemical modification with the photoswitchable gate, enables different wavelengths of light to switch action potential firing on and off. These synthetic photoisomerizable azobenzene-regulated K(+) (SPARK) channels allow rapid, precise and reversible control over neuronal firing, with potential applications for dissecting neural circuits and controlling activity downstream from sites of neural damage or degeneration. 相似文献
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Erez T. Yirmiya Ehud Mekori‐Domachevsky Ronnie Weinberger Michal Taler Miri Carmel Doron Gothelf 《American journal of medical genetics. Part A》2020,182(3):461-468
22q11.2 deletion syndrome (22q11.DS) is a neurogenetic disorder caused by a microdeletion in chromosome 22. Its phenotype includes high rates of psychiatric disorders, immune system abnormalities, and cognitive impairments. We assessed the quality of sleep in 22q11.2DS and its potential link to inflammatory markers and cognitive deficits. Thirty‐three 22q11.2DS individuals and 24 healthy controls were studied. Sleep parameters were assessed by the Pittsburgh sleep quality index (PSQI) questionnaire and correlated with serum cytokine levels and cognitive functioning, measured using the Penn computerized neurocognitive battery (CNB). The 22q11.2DS individuals had significantly worse sleep quality scores than the controls, unrelated to the psychiatric or physical comorbidities common to 22q11.2DS. Interleukin 6 levels were correlated with the overall score of the PSQI questionnaire for nonpsychotic 22q11.2DS participants only. Several domains of the CNB were associated with poorer sleep quality, suggesting that cognitive impairments in 22q11.2DS may be at least partially explained by poor sleep quality. Our findings confirm sleep impairments in individuals with 22q11.2DS, which might negatively affect their cognitive functioning, and corroborate a potential role of immunological pathways in the 22q11.2DS neuro‐phenotype. 相似文献
8.
Eldar-Geva T Margalioth EJ Gal M Ben-Chetrit A Algur N Zylber-Haran E Brooks B Huerta M Spitz IM 《Human reproduction (Oxford, England)》2005,20(7):1814-1819
BACKGROUND: Anti-Mullerian hormone (AMH) is expressed in pre- and small-antral follicles. High serum levels are found in women with polycystic ovaries (PCO), accordant with their increased content of small follicles. To evaluate the relationship between AMH, folliculogenesis and hyperandrogenism, we compared serum AMH levels between women with PCO with and without hyperandrogenism and normal controls during controlled ovarian hyperstimulation (COH). METHODS: Nineteen women with PCO and hyperandrogenism (group A), 10 women with PCO but no hyperandrogenism (group B) and 23 ovulatory women with normal ovarian morphology (group C, controls) underwent COH with the long protocol. Serum levels of AMH, estradiol, androstenedione and follicular tracking were determined before gonadotropins treatment (day 0) and every 2-4 days up to the day of HCG administration. RESULTS: AMH levels declined gradually throughout COH in the three groups, but remained higher in groups A and B compared with the controls. Significantly higher levels were found in group A compared with group B, despite comparable numbers of small follicles. Multiple regression analysis revealed that both the number of small follicles and serum androgens were correlated to AMH. CONCLUSIONS: Women with PCO have higher serum AMH levels during COH than controls. Hyperandrogenism is associated with an additional increase in AMH. It is conceivable that hyperandrogenism may reflect more severe disruption of folliculogenesis in women with PCO or may affect AMH secretion. 相似文献
9.
Tsai JC de Groot L Pinon JD Iacono KT Phillips JJ Seo SH Lavi E Weiss SR 《Virology》2003,312(2):369-380
Targeted recombination was carried out to select mouse hepatitis viruses (MHVs) in a defined genetic background, containing an MHV-JHM spike gene encoding either three heptad repeat 1 (HR1) substitutions (Q1067H, Q1094H, and L1114R) or L1114R alone. The recombinant virus, which expresses spike with the three substitutions, was nonfusogenic at neutral pH. Its replication was significantly inhibited by lysosomotropic agents, and it was highly neuroattenuated in vivo. In contrast, the recombinant expressing spike with L1114R alone mediated cell-to-cell fusion at neutral pH and replicated efficiently despite the presence of lysosomotropic agents; however, it still caused only subclinical morbidity and no mortality in animals. Thus, both recombinant viruses were highly attenuated and expressed viral antigen which was restricted to the olfactory bulbs and was markedly absent from other regions of the brains at 5 days postinfection. These data demonstrate that amino acid substitutions, in particular L1114R, within HR1 of the JHM spike reduced the ability of MHV to spread in the central nervous system. Furthermore, the requirements for low pH for fusion and viral entry are not prerequisites for the highly attenuated phenotype. 相似文献
10.
Purification and characterization of placental heparanase and its expression by cultured cytotrophoblasts 总被引:9,自引:2,他引:9
Goshen Ran; Hochberg Abraham A.; Korner Gill; Levy Ehud; Ishai-Michaeli Rivka; Elkin Michael; de Groot Nathan; Vlodavsky Israel 《Molecular human reproduction》1996,2(9):679-684
The role of different extracellular matrix (ECM)-degrading enzymesin the normal functioning of the placenta is well documented.Heparan sulphate proteoglycan (HSPG) is an integral constituentof the placental and decidual ECM. Because this proteoglycanspecifically interacts with various macromolecules in the ECM,its degradation may disassemble the matrix. Hence, in the caseof the placenta, this may facilitate normal placentation andtrophoblast invasion. Crude placental specimens were collectedfrom first and third trimester placentas. Heparanase (endo-P-glucuronidase)was isolated and purified by ammonium sulphate precipitationfollowed by sequential chromatographies on carboxymethyl-, heparin-and ConA-Sepharose columns. The placental enzyme was furthercharacterized for its molecular weight and specific inhibitionby heparin, and was shown to resemble heparanase expressed byhighly metastatic tumour cells and activated cells of the immunesystem. In order to locate the source of heparanase activityin the placenta, primary cytotrophoblast cultures were established.Intact cells, as well as conditioned medium and cell lysates,were analysed for heparanase activity using metabolically sulphate-labelledECM as a natural substrate. Heparanase was highly active inlysates of cytotrophoblasts. This activity was also expressedby intact cytotrophoblasts seeded on ECM, but no activity couldbe detected in the culture medium. Incubation of the cytotrophoblastsin contact with ECM resulted in release of ECM-bound basic fibroblastgrowth factor (bFGF). We propose that the cytotrophoblasticheparanase facilitates placentation, through cytotrophoblastextravasation and localized neovascularization. cytotrophoblast/extracellular matrix/heparanase/heparan sulphate proteoglycan/placenta 相似文献