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排序方式: 共有1001条查询结果,搜索用时 15 毫秒
91.
92.
Bourassa CV Rivière JB Dion PA Bernard G Diab S Panisset M Chouinard S Dupré N Fournier H Raelson J Belouchi M Rouleau GA 《PloS one》2011,6(1):e16254
Essential tremor (ET) is a complex genetic disorder for which no causative gene has been found. Recently, a genome-wide association study reported that two variants in the LINGO1 locus were associated to this disease. The aim of the present study was to test if this specific association could be replicated using a French-Canadian cohort of 259 ET patients and 479 ethnically matched controls. Our genotyping results lead us to conclude that no association exists between the key variant rs9652490 and ET (Pcorr = 1.00). 相似文献
93.
94.
Recombinant PCR has been used to generate linear fragments for promoter replacement by transformation in Aspergillus nidulans. A cassette vector carrying the pyr-4 non-homologous selectable marker and conditional promoter Pr-alcA was constructed for use as a template for PCR, and is suitable for testing the function of essential genes. Two genes involved in polar growth, cotA and bemA, were used to assess the system. Efficient targeting was possible with both genes using approximately 500bp of flanking homologous sequence. Depending on yield, the linear PCR product could be used directly for transformation, or after first cloning into a suitable vector. bemA, a putative homologue of the Saccharomyces cerevisiae BEM1 gene was identified through sequence comparison. In A. nidulans, this protein appears to have a similar role to the yeast Bem1p, which acts as a scaffold protein involved in the establishment of cell polarity. 相似文献
95.
Foroumadi A Emami S Hassanzadeh A Rajaee M Sokhanvar K Moshafi MH Shafiee A 《Bioorganic & medicinal chemistry letters》2005,15(20):4488-4492
A series of N-(5-benzylthio-1,3,4-thiadiazol-2-yl) and N-(5-benzylsulfonyl-1,3,4-thiadiazol-2-yl) derivatives of piperazinyl quinolones was synthesized and evaluated for antibacterial activity against Gram-positive and Gram-negative microorganisms. Some of these derivatives exhibit high activity against Gram-positive bacteria; Staphylococcus aureus and Staphylococcus epidermidis, comparable or more potent than their parent N-piperazinyl quinolones norfloxacin and ciprofloxacin as reference drugs. The SAR of this series indicates that both the structure of the benzyl unit and the S or SO(2) linker dramatically impact antibacterial activity. 相似文献
96.
Nasr-Esfahani M Moghadam M Tangestaninejad S Mirkhani V 《Bioorganic & medicinal chemistry letters》2005,15(13):3276-3278
Efficient oxidation of Hantzsch 1,4-dihydropyridines to their corresponding pyridine derivatives with (Bu(4)N)IO(4) catalyzed by tetraphenylporphyrinatomanganese(III) chloride [Mn(TPP)Cl] is reported. This catalytic system shows high efficiency in the oxidation of 1,4-dihydropyridines at room temperature in the presence of imidazole. 相似文献
97.
Dutta UK Lane J Roberts LJ Majid DS 《Experimental biology and medicine (Maywood, N.J.)》2006,231(3):269-276
To determine the role of superoxide (O(2)(-)) formation in the kidney during alterations in the renin-angiotensin system, we evaluated responses to the intra-arterial infusion of an O(2)(-) - scavenging agent, tempol, in the denervated kidney of anesthetized salt-depleted (SD, n=6) dogs and salt-replete (SR, n=6) dogs. As expected, basal plasma renin activity was higher in SD than in SR dogs (8.4 +/- 1.0 vs. 2.3 +/- 0.6 ng angiotensin 1/ml/hr). Interestingly, the basal level of urinary F(2)-isoprostanes excretion (marker for endogenous O(2)(-) activity) relative to creatinine (Cr) excretion was also significantly higher in SD compared to SR dogs (9.1 +/- 2.8 vs. 1.6 +/- 0.4 ng F(2)-isoprostanes/mg of Cr). There was a significant increase in renal blood flow (4.3 +/- 0.5 to 4.9 +/- 0.6 ml/min/g) and decreases in renal vascular resistance (38.2 +/- 5.8 to 33.2 +/- 4.7 mm Hg/ml/min/g) and mean systemic arterial pressure (148 +/- 6 to 112 +/- 10 mm Hg) in SD dogs but not in SR dogs during infusion of tempol at 1 mg/kg/min for 30 mins. Glomerular filtration rate and urinary sodium excretion (U(Na)V) did not change significantly during tempol infusion in both groups of dogs. Administration of the nitric oxide synthase inhibitor nitro-L-arginine (50 mug/kg/min) during tempol infusion caused a reduction in U(Na)V in SR dogs (47% +/- 12%) but did not cause a decrease in SD dogs. These data show that low salt intake enhances O(2)(-) activity that influences renal and systemic hemodynamics and thus may contribute to the regulation of arterial pressure in the salt-restricted state. 相似文献
98.
Metazoan Scc4 homologs link sister chromatid cohesion to cell and axon migration guidance 总被引:2,自引:0,他引:2 下载免费PDF全文
Seitan VC Banks P Laval S Majid NA Dorsett D Rana A Smith J Bateman A Krpic S Hostert A Rollins RA Erdjument-Bromage H Tempst P Benard CY Hekimi S Newbury SF Strachan T 《PLoS biology》2006,4(8):e242
99.
100.
Osborne NN Kamalden TA Majid AS del Olmo-Aguado S Manso AG Ji D 《Neurochemical research》2010,35(12):2027-2034
The retina captures and converts light between 400–760 nm into electrical signals that are sent to the brain by way of the
optic nerve and in the process helps to translate these electrical signals into what is known as vision. The same light that
allows vision to occur is nevertheless also potentially toxic to retinal cells in certain situations. The shorter wavelengths
of light are known to interact with chromophores in photoreceptors and pigment epithelial cells to cause oxidative stress
and severe damage. Indeed it is generally accepted that short wavelength light effects is one cause for loss of photoreceptor
function in age-related macular degeneration. Recent studies have demonstrated that light may be a contributing factor for
the death of retinal ganglion cells in certain situations. Light as impinging on the retina, especially the short wavelength
form, affect mitochondrial chromophores and can result in neurone death. Importantly ganglion cell axons within the eye are
laden with mitochondria and unlike the outer retina are not protected from short wavelength light by macular pigments. It
has therefore been proposed that when ganglion cell function is already compromised, as in glaucoma, then light impinging
on their mitochondria might be a contributor to their eventual demise. 相似文献