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221.
222.
Cysteine proteinases in bronchoalveolar epithelial cells and lavage fluid of rat lung 总被引:1,自引:0,他引:1
Y Ishii Y Hashizume T Watanabe S Waguri N Sato M Yamamoto S Hasegawa E Kominami Y Uchiyama 《The journal of histochemistry and cytochemistry》1991,39(4):461-468
We examined the presence of cathepsins B, H, and L in bronchoalveolar epithelial cells, including alveolar macrophages, and in bronchoalveolar lavage fluid (BALF), using immunocytochemistry and immunoblotting. By light and electron microscopy, immunoreactivity for cathepsins B, H, and L was detected in lysosomes of ciliated and non-ciliated epithelial cells of bronchi and bronchioles, and in macrophages. Immunodeposits for cathepsin H only were demonstrated in lamellar bodies of Type II alveolar epithelial cells, suggesting the cosecretion of surfactants and cathepsin H from the cells into the alveolar space. By immunoblotting, cathepsins B and H were found to be present in BALF. To further investigate the origin of these enzymes in BALF, alveolar macrophages obtained from BALF were cultured for 6 hr in a serum-free medium. Immunoblotting revealed that protein bands corresponding to the pro-form and mature form of cathepsin B and the mature form of cathepsin H were present in the culture medium. From these results, the presence of cathepsins B and H in BALF can be explained by the fact that cathepsin B is secreted from alveolar macrophages and cathepsin H is secreted mainly with surfactants from Type II cells and also from macrophages. 相似文献
223.
Summary Chromogranins (Cg)/secretogranins (Sg) are representative acidic glycoproteins in secretory granules of many endocrine cells where they are co-stored and co-released with resident amines or peptides. The exact distribution of these proteins in the rat anterior pituitary is unknown. Therefore, pituitaries from untreated male rats were investigated by light- and electron-microscopical immunocytochemistry for the cellular and subcellular localization of CgA, CgB, and SgII. Endocrine cells, identified light-microscopically as gonadotrophs in adjacent semithin sections immunostained for follicle-stimulating hormone (FSH) and luteinizing hormone (LH), concomitantly were immunoreactive for CgA, CgB, and SgII. Ultrastructurally, gonadotrophs exhibited two types of secretory granules which varied in their immunoreactivities for gonadotropins and Cg/Sg. Large-sized (500 nm), moderately electron-dense granules showed antigenicities for FSH, LH, and CgA. Smaller-sized (200 nm), electron-dense granules were immunoreactive exclusively for LH and SgII. The distinct localization of CgA and SgII to morphologically and hormonally different secretory granules indicates the existence of two regulated secretory pathways in rat pituitary gonadotrophs. Hence, these proteins are considered as valuable tools to analyze the intracellular trafficking during granule biogenesis and the possible different regulation of FSH and LH secretion. 相似文献
224.
Changes in the structure and biological property of N----O sulfate-transferred, N-resulfated heparin
The N----O sulfate transfer of heparin has been investigated as an approach to chemical 3-O-sulfation of the D-glucosamine residues in heparin. The pyridinium salt of porcine heparin was heated at 90 degrees C in solid state for 90 min (in vacuo over P2O5) to effect the transfer of the N-sulfate groups to the HO groups in the polysaccharide, followed by N-resulfation. The product (N----O sulfate-transferred, N-resulfated heparin (ST heparin] was depolymerized with HONO to generate a mixture of di- and higher oligosaccharides. The borohydride-reduced oligosaccharides were separated on Bio-Gel P-4 and DEAE-Sephacel. The disaccharide trisulfate fraction (10.4% yield) was found to be a mixture of nearly equal amounts of IdoA(2-SO4)-AManR(3,6-diSO4) and IdoA(2,3-diSO4)-AManR(6-SO4), where IdoA represents L-iduronic acid and AManR represents the alditol formed by reduction of 2,5-anhydro-D-mannose with NaBH4. Chemical and NMR spectroscopic analyses revealed that the N----O sulfate transfer proceeded preferentially at HO-3 positions in both 6-O-sulfo-D-glucosamine and 2-O-sulfo-L-iduronic acid residues. Chromatography on antithrombin III-Sepharose gel indicated that the structural change involved in ST heparin resulted in an obvious increase in the ability to bind antithrombin III. Biological examination also indicated that this structural change resulted in moderate increases in all the activities (blood anti-clotting, anti-Factor IIa, and anti-Factor Xa) and in the strength of intrinsic fluorescence of antithrombin III. 相似文献
225.
Equilibrium gel permeation chromatography was employed to determine the ability of heparin to form complexes with thrombin and antithrombin III. In the eluate from a Sephacryl S-200 column, heparin caused a peak and then a trough in the fluorescence of 48 nM antithrombin III or 63 nM thrombin. The peak-heights with known amounts of heparin were used for standard curves to determine the extent of complex formation by test heparin preparations. Only heparin species with high-affinity for antithrombin III specifically formed a complex with antithrombin III under the conditions used. The ability to form a complex of heparin preparations with different anticoagulant activities for thrombin and antithrombin III could be determined satisfactorily. The heparin species with different affinities for antithrombin III did not coincide those with different affinities for thrombin. Of 4 preparations with one low-affinity and three high-affinity subfractions of heparin for antithrombin III, the species with the lowest affinity for antithrombin III had the highest affinity for thrombin. All of these observations showed that the method could be used to determine the ability to form a complex of test heparin preparations. 相似文献
226.
Uchida M Harada T Enkhtuya J Kusumoto A Kobayashi Y Chiba S Shyaka A Kawamoto K 《Biochemical and biophysical research communications》2012,421(2):323-328
Bacillus anthracis spores germinate to vegetative forms in host cells, and produced fatal toxins. A toxin-targeting prophylaxis blocks the effect of toxin, but may allow to grow vegetative cells which create subsequent toxemia. In this study, we examined protective effect of extractable antigen 1 (EA1), a major S-layer component of B. anthracis, against anthrax. Mice were intranasally immunized with recombinant EA1, followed by a lethal challenge of B. anthracis spores. Mucosal immunization with EA1 resulted in a significant level of anti-EA1 antibodies in feces, saliva and serum. It also delayed the onset of anthrax and remarkably decreased the mortality rate. In addition, the combination of EA1 and protective antigen (PA) protected all immunized mice from a lethal challenge with B. anthracis spores. The numbers of bacteria in tissues of EA1-immunized mice were significantly decreased compared to those in the control and PA alone-immunized mice. Immunity to EA1 might contribute to protection at the early phase of infection, i.e., before massive multiplication and toxin production by vegetative cells. These results suggest that EA1 is a novel candidate for anthrax vaccine and provides a more effective protection when used in combination with PA. 相似文献
227.
Gotoh M Fujiwara Y Yue J Liu J Lee S Fells J Uchiyama A Murakami-Murofushi K Kennel S Wall J Patil R Gupte R Balazs L Miller DD Tigyi GJ 《Biochemical Society transactions》2012,40(1):31-36
LPA (lysophosphatidic acid, 1-acyl-2-hydroxy-sn-glycero-3-phosphate), is a growth factor-like lipid mediator that regulates many cellular functions, many of which are unique to malignantly transformed cells. The simple chemical structure of LPA and its profound effects in cancer cells has attracted the attention of the cancer therapeutics field and drives the development of therapeutics based on the LPA scaffold. In biological fluids, LPA is generated by ATX (autotaxin), a lysophospholipase D that cleaves the choline/serine headgroup from lysophosphatidylcholine and lysophosphatidylserine to generate LPA. In the present article, we review some of the key findings that make the ATX-LPA signalling axis an emerging target for cancer therapy. 相似文献
228.
Yosuke Tashiro Aya Inagaki Kaori Ono Tomohiro Inaba Yutaka Yawata Hiroo Uchiyama 《Bioscience, biotechnology, and biochemistry》2013,77(1):178-181
Biofilms are communities of surface-attached microbial cells that resist environmental stresses. In this study, we found that low concentrations of ethanol increase biofilm formation in Pseudomonas aeruginosa PAO1 but not in a mutant of it lacking both Psl and Pel exopolysaccharides. Low concentrations of ethanol also increased pellicle formation at the air–liquid interface. 相似文献
229.
At present, two methods for cloning mammals by nuclear transfer are employed. The first is based on cell fusion and has been applied to domestic animals, such as sheep, cows, and goats. While, nuclear microinjection has been used in mice only. Cloning by nuclear transfer has been reported mainly with cells from primary culture and freshly isolated cells. Here, using ES cell line TT2, we tried to produce clone mouse embryos by the two methods. With ES cell line TT2 (10-13 passaged), 16% of reconstructed oocytes microinjected with the nuclei developed in vitro to the morula/blastocycst stage, and 50% of these embryos developed to fetuses until 14 dpc when transferred to pseudopregnant females. At 20 dpc implanted sites were degenerated and absorbed. Also, in vitro development of embryos reconstructed by electrofusion shown similar results. But, when transferred to recipients, subsequent development of embryos showed lower rates, as compared with embryos microinjected and from recipients live-born pups could not be obtained. 相似文献
230.
Shinji Hadano Asako Otomo Ryota Kunita Kyoko Suzuki-Utsunomiya Akira Akatsuka Masato Koike Masashi Aoki Yasuo Uchiyama Yasuto Itoyama Joh-E Ikeda 《PloS one》2010,5(3)