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61.

Objective

Our case–control study aimed to access the potential association of insertion/deletion (I/D) ACE (angiotensin converting enzyme) gene polymorphism with myocardial infarction (MI) risk of occurrence among a sample of Moroccan patients, especially young ones.

Results

Distribution of I/D ACE gene variant among cases vs controls, showed that healthy controls carried out higher frequency of wild type allele I compared to cases (23.5% vs 21.79% respectively), when cases were carrying higher frequency of mutant allele D (78.21% vs 76.5% for controls). Patients were-after this- divided into two groups of < 45 and > 55 years of age, to investigate whether or not younger patients carried out higher frequency of the mutant allele D, than older ones. As expected, < 45 years old patients carried out more DD genotype than older ones (68.9% vs 54.6% respectively), and higher frequency of mutant allele D (81.08% vs 75% respectively). Besides, a tendency to a positive association was found under the recessive genetic transmission model (OR [95% CI] = 1.85 [0.93–3.69], P = 0.08), suggesting that the I/D ACE polymorphism may be associated with MI occurrence among younger patients (< 45 years of age).
  相似文献   
62.
Steroids influence the activity and plasticity of neurons and glial cells during early development, and they continue to exert trophic and protective effects in the adult nervous system. Steroids are produced by the gonads and adrenal glands and reach the brain, the spinal cord and the peripheral nerves via the bloodstream. However, some of them, named “neurosteroids”, can also be synthesized within the nervous system. They include pregnenolone, progesterone, dehydroepiandrosterone and their reduced metabolites and sulfate esters. Little is known concerning the regulation of steroid synthesis in the nervous system, which involves interactions between different cell types. For example, the synthesis of progesterone by Schwann cells in peripheral nerves is regulated by a diffusible neuronal signal. Neurotrophic and neuroprotective effects of steroids have been documented both in cell culture and in vivo. PROG plays an important role in the neurological recovery from traumatic injury of the brain and spinal cord by mechanisms involving protection from excitotoxic cell death, lipid peroxydation and the induction of specific enzymes. After transection of the rat spinal cord, PROG increases the number of nitric oxide synthase expressing astrocytes immediately above and below the lesion. PROG also plays an important role in the formation of new myelin sheaths. This has been shown in the regenerating mouse sciatic nerve after lesion and in cocultures of sensory neurons and Schwann cells. PROG promotes myelination by activating the expression of genes coding for myelin proteins. The modulation of neurostransmitter receptors, in particular the type A γ-aminobutyric acid, the N-methyl-D-aspartate and the sigma 1 receptors, is involved in the psychopharmacological effects of steroids and allows to explain their anticonvulsant, anxiolytic, antidepressive and sedative effects as well as their influence on memory. Pregnenolone sulfate has been shown to reverse age-related deficits in spatial memory performance and to have protective effects on memory in different models of amnesia.  相似文献   
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64.
The synthesis of a new family of D4T analogues is described to study the influence of pyrazinone base on antiretroviral power. Substitution of 3H by methyl or n-decyl increases the lipophilic character and may facilitate diffusion across cell membranes. The compounds were characterized by 1H NMR and infrared spectroscopy. Antiviral (HIV-1) properties of these compounds were examined.  相似文献   
65.
A total of 21 isolates of Vibrio cholerae non-O1 strains were isolated from three wastewater treatment plants in Agadir, Morocco. The isolates were analyzed by biochemical analysis, antibiogram, pulsed-field gel electrophoresis and the MALDI-TOF patterns of their protein masses were compared. Over 67% of isolates were susceptible to antimicrobial agents tested and 14% proved resistant to both trimethoprim-sulfamethoxazole and nalidixic acid. Typing by pulsed-field gel electrophoresis with NotI digestion revealed that the V. cholerae non-O1 strains from Agadir (Morocco) have a lower level of genetic homogeneity, the restriction patterns of whole-chromosomal DNA grouped the V. cholerae O1 and V. alginolyticus strains into a separate cluster from V. metschnikovii and V. cholerae non-O1 isolates. Furthermore, to gain additional analytical accuracy and reliability in the analysis we used dendrogram based on MALDI-TOF spectral patterns generated by the BioTyper 1.1™ software. All m/z signatures of all strains tested indicate that the mass spectral data contained sufficient information to distinguish between strains of V. cholerae.  相似文献   
66.
This paper describes the synthesis of new click-generated nitrogen mustards and their biological evaluation. By using the copper-catalyzed azide-alkyne cycloaddition (CuAAC) reaction, we managed to synthesize eight new nitrogen mustards. This strategy paves the way for the synthesis of a new family of nitrogen mustard, with an important structural variability. Furthermore, we studied the biological activity of synthesized compounds by testing their cytotoxicity on four representative cancer cell lines A431, JURKAT, K562, and U266. One structure, 1-benzyl-4-(N,N-di-2-chloroethylaminomethyl)-1H-[1 Noll, D.M.; McG.Mason, T.; Miller, P.S. Formation and repair of interstrand cross-links in DNA. Chem. Rev. 2006, 106, 277301.[Crossref], [PubMed], [Web of Science ®] [Google Scholar],2 Rink, S.M.; Hopkins, P.B. Direct evidence for DNA intrastrand cross-linking by the nitrogen mustard mechlorethamine in synthetic oligonucleotides. Bioorg. Med. Chem. Lett. 1995, 5(23), 28452850.[Crossref], [Web of Science ®] [Google Scholar],3 Chabner, B.A.; Collins, J.M. Cancer Chemotherapy: Principles and Practices, PA, J.B. Lippincott Company, Philadelphia, 1990, pp. 276313. [Google Scholar]]triazole, showed an interesting cytotoxic effect.  相似文献   
67.
Somatic embryogenesis of olive Olea europaea (L.) ‘Chetoui’ was studied using cell suspension cultures initiated from mature leaf-derived calli. Calli were developed on half-strength MS medium supplemented with 10 μM NAA and 2.25 μM 2i-P in the dark. Different combinations of three plant growth regulators (2,4-D, NAA and zeatin) were tested to determine cell proliferation and somatic embryogenesis induction and differentiation. Embryogenic suspension cultures were established in olive-modified medium for embryogenesis (OMe) containing 2.5 μM 2,4-D and 2.5 μM zeatin. Pre-globular and globular embryos were induced from mature olive tissue in liquid medium. In addition, the nitrogen form as inorganic (reduced; (NH4)2SO4 or oxidized; KNO3) and organic (CH) was used separately or in combination to improve the cell growth and proliferation. The most effective growth rate and cell proliferation were obtained with the medium containing inorganic and organic nitrogen forms.  相似文献   
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69.
The short-term effects of p -chloromercuribenzenesulphonic acid (PCMBS) on the transmembrane potential difference (PD) of broad bean ( Vicia faba L. cv. Aguadulce) cotyledon cells and on sugar beet ( Beta vulgaris L. cv. Klein E.) leaf cells were studied by the electrophysiological method. These effects were compared with that of the permeant thiol reagents N-ethylmaleimide and HgCl2. N-Ethylmaleimide and HgCl2 markedly and rapidly depolarised the PD of all the material studied, while PCMBS caused either a slight depolarisation (cotyledon cells) or no depolarisation (leaf cells) during the first 30 min of treatment. In cotyledons, PCMBS markedly inhibited sucrose uptake (89%) and the sucrose-induced depolarisation associated with the proton-sucrose symport (67%), while it decreased the proton-motive force only marginally (7%). It is concluded that during short treatments (30 min or less). PCMBS inhibits sucrose uptake directly by blocking the sucrose carrier, and not the proton pump. For longer treatments, indirect effects cannot be excluded.  相似文献   
70.
After traumatic brain injury, progesterone has important neuroprotective effects in the nervous system. There is better functional outcome and less oedema formation in pseudopregnant rat females (high levels of endogenous progesterone) than in males. In addition to intracellular progesterone receptors, membrane binding sites of the hormone such as 25-Dx may also be involved in neuroprotection. In the present study we investigated the distribution of the membrane-associated progesterone-binding protein 25-Dx in rat brain. Immunohistochemical analysis showed that 25-Dx is particularly abundant in the hypothalamic area, circumventricular organs, and ependymal cells of the lateral walls of the third and lateral ventricles. A strong signal was also detected in the meninges. Double immunofluorescence immunolabelling and confocal microscopy showed that 25-Dx is co-expressed with vasopressin in neurones of the paraventricular, supraoptic and retrochiasmatic nuclei. Levels of 25-Dx expression were higher in pseudopregnant females than in males. After traumatic brain injury, 25-Dx expression was up-regulated in neurones and induced in astrocytes, which play an important role in regulating water and ion homeostasis. The expression of 25-Dx in structures involved in CSF production (choroid plexus) and in osmoregulation (circumventricular organs, hypothalamus and meninges), and its up-regulation after brain damage, point to a novel and potentially important role of this progesterone-binding protein in the maintenance of water homeostasis after traumatic brain injury.  相似文献   
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