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51.
C-Type natriuretic peptide (CNP) is a vasoactive hormone and the endothelial component of the natriuretic peptide system. We examined the expression of CNP in mouse reproductive organs and embryos at different stages of gestation. Pregnant mice were killed and embryos were dissected on gestational days 9.5, 12.5, 15.5, 18.5 postconceptionem (pc) and at term. Nonpregnant mice were used as controls. Total RNA was isolated from placenta, ovaries, myometrium and from head and trunk of embryos and neonates. CNP-mRNA was quantified by ribonuclease-protection assay (RPA). Uterine CNP-mRNA concentrations increase during pregnancy up to the sevenfold concentration, whereas in the ovaries these levels decrease to 10% compared to nonpregnant controls. In the placenta, a peak of CNP expression has been observed around day 15.5 pc, whereby placenta showed the strongest CNP signals. CNP-mRNA concentrations in embryos are gestational age-dependent with a high level at day 9.5 pc in head and trunk. These results indicate that CNP has a regulatory function in pregnancy and embryonic development.  相似文献   
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Tartrate-resistant acid phosphatase type-5 was purified to apparent homogeneity from human osteoclastomas by sequential chromatography on CM-Sepharose, Phenyl-Sepharose, concanavalin A-Sepharose, FPLC Superose-12, and FPLC Mono-S. The purification over the original tissue extract was 1167-fold, with a yield of 16%. An identity in the N-terminal amino acid sequence and Mr was found between this enzyme and two type-5 tartrate-resistant acid phosphatases isolated from hairy cell leukemia spleen. However, they appeared to be different as assessed by amino acid composition. In contrast to a previous report, no evidence was found for two subunits of the tartrate-resistant acid phosphatase.  相似文献   
53.
The NO/sGC/cGMP/PKG system is one of the most powerful mechanisms responsible for platelet inhibition. In numerous publications, expression of functional NO synthase (NOS) in human and mouse platelets has been reported. Constitutive and inducible NOS isoforms convert l-arginine to NO and l-citrulline. The importance of this pathway in platelets and in endothelial cells for the regulation of platelet function is discussed since decades. However, there are serious doubts in the literature concerning both expression and functionality of NOS in platelets. In this review, we aim to present and critically evaluate recent data concerning NOS expression and function in platelets, and to especially emphasise potential pitfalls of detection of NOS proteins and measurement of NOS activity. Prevailing analytical problems are probably the main sources of contradictory data on occurrence, activity and function of NOS in platelets. In this review we also address issues of how these problems can be resolved. NO donors including organic nitrites (RONO) and organic nitrate (RONO2) are inhibitors of platelet activation. Endogenous inorganic nitrite (NO2 ?), the product of NO autoxidation, and exogenous inorganic nitrite are increasingly investigated as NO donors in the circulation. The role of platelets in the generation of NO from nitrite is also discussed.  相似文献   
54.
The therapy of radioresistant tumors remains an urgent problem in medicine. To solve this problem neutron capture therapy (NCT) and photon activation therapy (PAT) are used. The essential feature of this such technique is the uptake of tumor chemical elements, which interact with thermal neutrons (NCT) and X-rays (PAT). The aims of the investigation were to study a biodistribution of the complexes of hyaluronic acid with boron (3 mg B mL?1) and gold (20 mg Au mL?1) in mice with melanoma B-16 after intratumoral administration. An optimal time for NCT was 30 minutes after administration when boron concentration in the tumor was more than 30 μg g?1 and exceeded boron content in surrounding tissues. The maximal gold content in tumor (180–260 mg g?1) was obtained in 30 minutes after the preparation introduction. The highest ratios of gold in tumor and surrounding tissues (a necessary condition for forming of the local absorbed dose in tumor) was obtained in 0.5 and 1 h. On the basis of the data obtained, it is possible to assume the perspectives of the non-toxic boron compounds for use in NCT and the gold compounds for use primarily as contrast agents for diagnostic purposes.  相似文献   
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Deep subsurface horizons used for the disposal of liquid low- and intermediate-level radioactive wastes of the Siberian Chemical Complex (SCC, Russia) were studied by microbiological, radioisotope, and molecular biological methods. It was shown that a diverse microbial community inhabited the groundwater. The cell numbers of microorganisms of the major metabolic groups and the rates of sulfate reduction, denitrification, and methanogenesis in natural groundwater were low and increased in the zone of wastes dispersion. More than 40 strains belonging to the genera Kocuria, Microbacterium, Pseudomonas, Pantoea, Acinetobacter, Enterobacter, Klebsiella, Stenotrophomonas, Sphingomonas, Staphylococcus, Acidivorax, Shewanella, and Desulfosporosinus were isolated from the disposal sites. Among the isolates, the microorganisms were found that were able to concentrate actinides and other transuranium elements. Aerobic bacteria were able to sorb various radionuclides in laboratory experiments; however, biosorption was low in sample of groundwater and in carbonate solutions containing several radionuclides. Reduction of U(VI) by a sulfate-reducing enrichment culture from the site and reduction of U(VI) and Np(V) by an isolate Shewanella were observed in the presence of various organic substrates. These results show the necessity of further ecosystem characterization based on microbiological and radiochemical studies and modeling of biogeochemical processes at the deep disposal sites for liquid radioactive wastes.  相似文献   
57.
Neuropeptide S (NPS) increasingly emerges as a potential novel treatment option for anxiety diseases like panic and posttraumatic stress disorder. However, the neural underpinnings of its anxiolytic action are still not clearly understood. Recently, we reported that neurons of the ventral hippocampus (VH) take up intranasally administered fluorophore-conjugated NPS and, moreover, that application of NPS to mouse brain slices affects neurotransmission and plasticity at hippocampal CA3-CA1 synapses. Although these previous findings define the VH as a novel NPS target structure, they leave open whether this brain region is directly involved in NPS-mediated anxiolysis and how NPS impacts on neuronal activity propagation in the VH. Here, we fill this knowledge gap by demonstrating, first, that microinjections of NPS into the ventral CA1 region are sufficient to reduce anxiety-like behavior of C57BL/6N mice and, second, that NPS, via the NPS receptor, rapidly weakens evoked neuronal activity flow from the dentate gyrus to area CA1 in vitro. Additionally, we show that intranasally applied NPS alters neurotransmission and plasticity at CA3-CA1 synapses in the same way as NPS administered to hippocampal slices. Thus, our study provides, for the first time, strong experimental evidence for a direct involvement of the VH in NPS-induced anxiolysis and furthermore presents a novel mechanism of NPS action.  相似文献   
58.
Preeclampsia is a serious cardiovascular complication in pregnancy which is associated with an increased future metabolic and cardiovascular risk for mother and newborn. Recently, chemerin was introduced as a novel adipokine inducing insulin resistance in vitro and in vivo. In the current study, we investigated serum concentrations of chemerin by ELISA in control and preeclampsia patients during pregnancy (Control: n=37, preeclampsia: n=37) and 6 months after delivery (Control: n=35, preeclampsia: n=36). Furthermore, the association between chemerin and markers of renal function, glucose and lipid metabolism, as well as inflammation was studied in pregnant patients. Median maternal chemerin concentrations were significantly elevated in preeclampsia patients (249.5 [range: 123.1-366.9] μg/l) as compared to controls (204.8 [138.5-280.8] μg/l) (p<0.001). Furthermore, chemerin serum levels positively correlated with blood pressure, creatinine, free fatty acids, cholesterol, triglycerides (TG), leptin, adiponectin, and C-reactive protein in univariate analyses. In multivariate analyses, TG and leptin remained independently associated with circulating chemerin. Interestingly, median chemerin concentrations 6 months after delivery remained significantly higher in former preeclampsia patients (196.0 [119.8-368.7] μg/l) as compared to controls (152.2 [102.8-216.4] μg/l). Taken together, maternal chemerin serum concentrations are significantly increased in preeclampsia during and after pregnancy. Furthermore, TG and leptin are independent predictors of circulating chemerin during pregnancy.  相似文献   
59.
Expression of the genes Ubx, abd-A, and Abd-B of the bithorax complex depends on its cis-regulatory region, which is divided into discrete functional domains (iab). Boundary/insulator elements, named Mcp, Fab-6, Fab-7 and Fab-8 (PTS/F8), have been identified at the borders of the iab domains. Recently, binding sites for a Drosophila homolog of the vertebrate insulator protein CTCF have been identified in Mcp, Fab-6 and Fab-8 and also in several regions that correspond to predicted boundaries, Fab-3 and Fab-4 in particular. Taking into account the inability of the yeast GAL4 activator to stimulate the white promoter when the activator and the promoter are separated by a 5-kb yellow gene, we have tested functional interactions between the boundaries. The results show that all dCTCF-containing boundaries interact with each other. However, inactivation of dCTCF binding sites in Mcp, Fab-6 and PTS/F8 only partially reduces their ability to interact, suggesting the presence of additional protein(s) supporting distant interactions between the boundaries. Interestingly, only Fab-6, Fab-7 (which contains no dCTCF binding sites) and PTS/F8 interact with the upstream region of the Abd-B promoter. Thus, the boundaries might be involved in supporting the specific interactions between iab enhancers and promoters of the bithorax complex.  相似文献   
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