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71.
72.
A newly identified member of the fibroblast growth factor (FGF) family, designated FGF-10, is expressed during development and preferentially in adult lung. The predicted FGF-10 protein is most related to keratinocyte growth factor (KGF, or FGF-7). The latter is unique among FGFs in that it binds and signals only through the FGF receptor (FGFR2b) isoform KGF receptor (KGFR) expressed specifically by epithelial cells. In order to examine the biological and biochemical properties of human FGF-10, we isolated the cDNA and expressed its encoded protein in bacteria. The recombinant protein (rFGF-10) was a potent mitogen for Balb/MK mouse epidermal keratinocytes with activity detectable at 0.1 nM and maximal at around 5 nM. Within this concentration range, FGF-10 did not stimulate DNA synthesis in NIH/3T3 mouse fibroblasts. rFGF-10 bound the KGFR with high affinity comparable to that of KGF, and did not bind detectably to either the FGFR1c (Flg) or FGFR2c (Bek) receptor isoforms. The mitogenic activity of FGF-10 could be distinguished from that of KGF by its different sensitivity to heparin and lack of neutralization by a KGF monoclonal antibody. These results indicate that FGF-10 and KGF have similar receptor binding properties and target cell specificities, but are differentially regulated by components of the extracellular matrix.  相似文献   
73.
BACKGROUND: Astigmatic keratotomy is used conventionally to correct moderate surgical astigmatism. However, cases with very high surgical astigmatism due to wound compression can show a dramatic response to relaxing keratotomies made in the steeper meridian. The effect obtained cannot be predicted pre-operatively by using standard nomograms. METHODS: Coupled arcuate keratotomies combined with corneal valvular incisions were performed in a case of high astigmatism post-cataract surgery. RESULTS/CONCLUSION: Coupled arcuate keratotomies were combined with a corneal valvular incision enabled a surgical correction of nearly 9 D of astigmatism.  相似文献   
74.
Preincubation of microsomes from male Wistar rats with imipramine (IMI) in the presence of NADPH caused a time-dependent loss of bunitrolol 4-hydroxylase activity, indicating that the CYP2D enzyme is inactivated during IMI metabolism, which has also been observed after in vivo administration of IMI. A similar effect was obtained when desipramine, an N-demethylated metabolite of IMI, was used as an inhibitor, whereas 2-hydroxy-IMI had no effect on the activity. Thus, it seems likely that the inactivation of the CYP2D enzyme is related to 2-hydroxylation process of IMI. Incubation of microsomes with [3H]IMI in the presence of NADPH resulted in covalent binding of a 3H-labeled material to microsomal protein. Formation rates of the reactive metabolites covalently bound to protein followed Michaelis-Menten kinetics, and the K(m) value (1.1 microM) was close to that for microsomal IMI 2-hydroxylation. The metabolism-dependent covalent binding of [3H]IMI was lower in Dark Agouti rats, which is an animal model of CYP2D deficiency, than in Wistar rats. The binding was inhibited by propranolol and quinidine, a substrate and an inhibitor of CYP2D, respectively, and by an antibody against CYP2D. Similar strain difference (Dark Agouti < Wistar) and inhibitory effects by the compounds and the antibody were observed in IMI 2-hydroxylase but not in N-demethylase activity. SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis) of microsomal protein incubated with [3H]IMI and NADPH showed that the binding was prominent at the molecular mass of approximately 50 kDa, which would be consistent with the P450 protein being a target for the binding. Furthermore, proteins to which [3H]IMI metabolites covalently bound were immunoprecipitated with the anti-CYP2D antibody. These results suggest that IMI is biotransformed into a chemically reactive metabolite (probably arene-oxide) through its 2-hydroxylation step by the CYP2D enzyme in rat liver microsomes, and the metabolite binds covalently to the enzyme itself, resulting in the inactivation.  相似文献   
75.
Specific expression of the structure-specific recognition protein (SSRP) gene was investigated in rat fetal, adult, and tumor tissues using a 2.0-kb partial sequence of rat SSRP cDNA isolated from a cDNA library of rat renal cell carcinoma. The results revealed that it was rather specifically expressed in rat fetal kidney and renal cell carcinoma induced by Fenitrilotriacetate, but not in adult kidney, when various organs were tested by Northern blot analysis. In situ hybridization further demonstrated that it was located in the neoplastic cells of renal cell carcinoma and in the epithelial cells of fetal kidney but undetectable in any cells of normal adult kidney. These observations seem to imply the involvement of SSRP gene, which is believed to recognize structural alterations of DNA, in kidney development and carcinogenesis of certain types of kidney cancer.  相似文献   
76.
77.
We previously isolated a novel protein having two C2-like domains known to interact with Ca2+ and phospholipid, and named Doc2 (Double C2). Doc2 is predominantly expressed in brain and is implicated in Ca(2+)-dependent neurotransmitter release. We have isolated here an isoform of Doc2 and named the original one Doc2 alpha and the new one Doc2 beta. Doc2 beta alsp has two C2-like domains and is 61% identical to Doc2 alpha at the amino acid level. In contrast to Doc2 alpha, the Doc2 beta mRNA is expressed ubiquitously. These results indicate that there are at least two isoforms of Doc2, and suggest that Doc2 beta is involved in Ca(2+)-dependent intracellular vesicle trafficking in various types of cells.  相似文献   
78.
A 19-year-old woman was admitted to Kushiro city general hospital due to chest pain and dyspnea. Chest radiographs and computed tomographic scan showed a large intrathoracic mass adjacent to the pleura. Angiographs disclosed feeding veins of the tumor arising from lateral thoracic artery. Fine-needle aspiration cytology of the tumor revealed small round cells with a large nuclear/cytoplasmic ratio. Immunocytochemical study demonstrated that the tumor cells were positive for neuron-specific enolase and MIC 2 gene product. The diagnosis was primitive neuroectodermal tumor of the parietal pleura (also known as Askin tumor). Chemotherapy combined with peripheral blood stem cell transplantation reduced the size of the tumor significantly. However, multiple bone metastasis recurred, and the patient died 35 months after the start of therapy.  相似文献   
79.
The use of electron spin resonance for measurement of the ground state population (GSP) of Cr3+in a ruby rod during optical pumping is described. For a 7.7 cm long rod at 90°K and a mirror reflectance productR_{1}R_{2} > 0.08, the GSP at laser threshold was found to be 55 ± 5 percent in good agreement with theory and previous optical measurements. At room temperature, a limiting value of approximately 30 percent for the GSP was approached at high pump energies. Observations of the relativeR_{1}(3/2), R_{1}(1/2)thresholds at 90°K as a function of mirror reflectivity indicated that the2E excited state absorption cross section at the laser wavelength is less than5 times 10^{-21}cm2. Detection of total internal reflection oscillations in cooled ruby lasers from ESR observations is also described.  相似文献   
80.
Drug susceptibility of 430 Staphylococcus aureus strains isolated in 1991 from clinical specimens at all of the Japanese national university hospitals was evaluated in relationship with the epidemiological markers, namely, coagulase typing, and staphylococcal enterotoxins (SE) and toxic shock syndrome toxin 1 (TSST-1) production. There were five major methicillin-resistant Staphylococcus aureus (MRSA) groups in all the 252 MRSA strains: coagulase-type II-SEC + TSST-1- producing strains (II-SEC + TSST-1): 34.5%; coagulase-type II-no toxin-producing strains (II-): 15.4%; coagulase-type IV-SEA-producing strains (IV-SEA): 10.3%; coagulase-type II-SEA + SEC + TSST-1- producing strains (II-SEA + SEC + TSST-1): 8.7%; and coagulase-type III-no toxin-producing strains (III-): 7.1%. II-SEA + SEC + TSST-1 group was highly resistant to OFLX, whereas half of the other strain groups were sensitive to OFLX. Seventy-eight percent of the IV-SEA group was sensitive to FMOX, but there was no sensitive strain to FMOX in the II-SEA + SEC + TSST-1 group. More than 50% of the IV-SEA, III- and II-groups were sensitive to IPM, while the II-SEC + TSST-1 and II-SEA + SEC + TSST-1 groups were highly resistant to IPM. The III- and II-groups showed very good sensitivity to MINO, but the sensitivity to it of the II-SEA + SEC + TSST-1 group was very low. All of the strain groups were sensitive to ST except for the IV-SEA group. These results may provide useful information in the choice of antibacterial agents for MRSA infection.  相似文献   
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