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73.
Starting from (+)-epi- and (-)-vibo-quercitols readily produced by bioconversion of myo-inositol, some biologically interesting phosphate and polyphosphate analogues, including the Ins(1,4,5)P(3) derivatives of 3-deoxy- and 6-deoxy-D-myo-inositol, could be readily prepared in a conventional manner. In addition, chemical modification at C-2 of the 3-deoxy Ins(1,4,5)P(3) provided 2-epimer, and 2-deoxy and 2-deoxy-2-fluoro forms. Eight polyphosphate analogues obtained were assayed for biological activity against PDH-Pase and PDH-K, and G6Pase, but none proved positive.  相似文献   
74.
Arsenic (+3 oxidation state) methyltransferase (As3MT) catalyzes the methylation of trivalent arsenic (As(III)) to monomethylarsonate (MMA(V)) and dimethylarsinic acid (DMA(V)), and plays an important role in the detoxification of arsenicals. Here, we report the identification of two splicing variants of the human As3MT gene. One splicing variant was an exon-3 skipping (Δ3) form which produced a premature stop codon, and the other was an exon-4 and -5 skipping (Δ4,5) form which produced a 31.1 kDa As3MT protein. In addition to the full-length mRNA of As3MT, Δ4,5 mRNAs were detected in HepG2, A549, HL60, K562, and HEK293 cells. The methyltransferase activity of the recombinant Δ4,5 As3MT and wild-type As3MT proteins purified from Escherichia coli was determined. Speciation analysis by HPLC–ICP-MS showed a clear peak of MMA(V) after incubation of As(III) with the wild-type As3MT protein, but not with the Δ4,5 As3MT protein. In addition, COS-7 cells transfected with Δ4,5 As3MT cDNA did not convert As(III) to MMA(V) or DMA(V). The lack of methyltransferase activity of Δ4,5 As3MT seems to be related to the deletion of an S-adenosylmethionine-binding site and a critical cysteine residue. These data suggest that the expression pattern of splicing variants of the As3MT gene may affect the capacity for arsenic methylation in cells.  相似文献   
75.
Synthetic method of novel prostaglandin (PG) mimetic: FR181175 without PG skeleton are described. The key to success is creation of a chiral epoxide using Sharpless AD reaction with high ee yield. FR181157 shows high potency and agonist efficacy at the IP receptor and has good bioavailability.  相似文献   
76.
This paper reports the synthesis and insecticidal activity of a series of novel 4-hydroxy-3-mesityl-1-methoxymethoxy-1,5-dihydro-2H-pyrrol-2-one derivatives, in which the substituents at the 5-position were varied with a number of alkyl and spirocycloalkyl groups. Investigation of the structure-activity relationships revealed that small alkyl and spirocyclohexyl groups had a favorable effect on the insecticidal activity of these agents against Myzus persicae.  相似文献   
77.
Organic solar cells (OSCs) are promising low‐cost devices for generating electricity. In addition to fill factor, the short circuit current density (JSC) and the open circuit voltage (VOC) are two key factors that have critical influence on the device performance. The energy levels of the donor and acceptor materials are crucial for achieving a high JSC and VOC. However, the interfacial structures between the organic materials substantially affect the JSC and VOC through the energy of the charge transfer (CT) states and the charge separation and recombination reaction kinetics. Here, it is reported that separating the donor and acceptor layer in bilayer OSCs with a thin insulating layer increases the energy of the CT state by weakening the Coulomb interaction at the interface and this also suppresses photoinduced CT and recombination. Although these effects usually increase VOC and decrease JSC, the trade‐off is avoided by doping the insulating layer with a dye to utilize the energy transfer process. The increase in VOC without the reduction in JSC enhances the conversion efficiency of the OSCs by 30%.  相似文献   
78.
Mental health is one of the most important issues facing disaster survivors. The purpose of this study is to determine the prevalence and correlates of mental health problems in survivors of the Great East Japan Earthquake and Tsunami at 6–11 months after the disaster. The questionnaire and notification were sent to the survivors in three municipalities in the Tohoku area of the Northern part of Honshu, Japan’s largest island, between September 2011 and February 2012. Questionnaires were sent to 12,772, 11,411, and 18,648 residents in the Yamada, Otsuchi, and Rikuzentakata municipalities, respectively. Residents were asked to bring the completed questionnaires to their health check-ups. A total of 11,124 or (26.0%) of them underwent health check-ups, and 10,198 were enrolled. We excluded 179 for whom a K6 score was missing and two who were both 17 years of age, which left 10,025 study participants (3,934 male and 6,091 female, mean age 61.0 years). K6 was used to measure mental health problems. The respondents were classified into moderate (5–12 of K6) and serious mental health problems (13+). A total of 42.6% of the respondents had moderate or serious mental health problems. Multivariate analysis showed that women were significantly associated with mental health problems. Other variables associated with mental health problems were: younger male, health complaints, severe economic status, relocations, and lack of a social network. An interaction effect of sex and economic status on severe mental health problems was statistically significant. Our findings suggest that mental health problems were prevalent in survivors of the Great East Japan Earthquake and Tsunami. For men and women, health complaints, severe economic status, relocations, and lack of social network may be important risk factors of poor mental health. For men, interventions focusing on economic support may be particularly useful in reducing mental health problems after the disaster.  相似文献   
79.
The relationship between the food demand of a clam population (Ruditapes philippinarum (Adams & Reeve 1850)) and the isotopic contributions of potential food sources (phytoplankton, benthic diatoms, and organic matter derived from the sediment surface, seagrass, and seaweeds) to the clam diet were investigated. In particular, we investigated the manner in which dense patches of clams with high secondary productivity are sustained in a coastal lagoon ecosystem (Hichirippu Lagoon) in Hokkaido, Japan. Clam feeding behavior should affect material circulation in this lagoon owing to their high secondary productivity (ca. 130 g C m−2 yr−1). Phytoplankton were initially found to constitute 14–77% of the clam diet, although phytoplankton nitrogen content (1.79–4.48 kmol N) and the food demand of the clam (16.2 kmol N d–1) suggest that phytoplankton can constitute only up to 28% of clam dietary demands. However, use of isotopic signatures alone may be misleading. For example, the contribution of microphytobenthos (MPB) were estimated to be 0–68% on the basis of isotopic signatures but was subsequently shown to be 35±13% (mean ± S.D.) and 64±4% (mean ± S.D.) on the basis of phytoplankton biomass and clam food demand respectively, suggesting that MPB are the primary food source for clams. Thus, in the present study, the abundant MPB in the subtidal area appear to be a key food source for clams, suggesting that these MPB may sustain the high secondary production of the clam.  相似文献   
80.
Sarcoma-like cells (SCLs) were derived from endarterectomized tissue of a single chronic thromboembolic pulmonary hypertension (CTEPH) patient during incubation of those thrombi at second passage as described at our previous report. These cells had malignant potential, with an increased expression of matrix metalloproteinase-14 (MMP-14), leading to tumor emboli within pulmonary arteries in in vivo studies. The purpose of this study was to perform a more detailed evaluation of the characteristics of SCLs, and to elucidate the role of the increased expression of MMP-14 expression in the growth and death of these cells. In order to elucidate the characteristics of SCLs and to confirm the protein expression of MMP-14, three-dimentional culture, invasion assays, a Western blot analysis and immunohistochemical studies were performed. To examine the role of MMP-14 in tumorigenesis, the metalloproteinase inhibitor, batimastat, was administered to SCID mice which were subcutaneously injected with SCLs. Those mice were sacrificed on day 14 and the tumor volume was evaluated. A Western blot analysis showed the increased expression of MMP-14 in comparison to the expression in lung adenocarcinoma cells (A549). Immunohistochemistry showed that SCLs were positive for vimentin, MMP-14, MMP-2 and CD44. However, endothelial markers, such as CD31 and von Willebrand factor (vWF), were negative. The in vivo studies demonstrated that batimastat could suppress the growth of the subcutaneous tumors formed by the SCLs. This study suggested that MMPs had critical roles on the pathological activities of SCLs and that batimastat might have anti-proliferative and anti-invasive effects on these cells.  相似文献   
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