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排序方式: 共有140条查询结果,搜索用时 265 毫秒
121.
R. Khan S. Burton S. Morley S. Daya B. Potgieter 《Cellular and molecular life sciences : CMLS》1990,46(1):88-89
Summary Prior melatonin administration (1,5 and 10 mg/kg b. wt) causes a significant reduction in gastric ulceration induced in male rats by restraint immobilization in the presence of low temperatures. 相似文献
122.
A S Khan A S Wilcox M H Polymeropoulos J A Hopkins T J Stevens M Robinson A K Orpana J M Sikela 《Nature genetics》1992,2(3):180-185
We have performed single pass sequencing of 1,024 human brain cDNAs, over 900 of which seem to represent new human genes. Library prescreening with total brain cDNA significantly reduced repeated sequencing of highly represented cDNAs. A subset of sequenced cDNAs were physically mapped to their chromosomal locations using gene-specific STS primers derived from 3' untranslated regions. We have also determined that human brain cDNAs represent a rich source of gene-associated polymorphic markers. Microsatellite-containing cDNAs can be physically mapped and converted to highly informative genetic markers, thus facilitating integration of the human physical, expression and genetic maps. 相似文献
123.
We report physicochemical characteristics of various kinds of liquid milk commercially available in Pakistan in comparison with those of fresh natural milk from animals. Milk samples were collected from local markets at Peshawar, Pakistan, and analyzed for their physical features, including moisture, total solids, specific gravity, conductivity, viscosity and titratable acidity (lactic acid equivalent), and chemical components and macro-minerals, including total protein, casein, lactose, ash and minerals (Na, K and Mg). These items were compared with the physicochemical characteristics of the fresh natural milk samples from buffalo, cow and goat. The results were also compared with reported nutritional quality of milk from various countries and World Health Organization (WHO) standards. We found that all the physical features and chemical components of commercially available milk in Pakistan markets meet WHO's requirements, except for Na, K, Ca and Mg, which are below the standards. 相似文献
124.
Avian flu: isolation of drug-resistant H5N1 virus 总被引:1,自引:0,他引:1
Le QM Kiso M Someya K Sakai YT Nguyen TH Nguyen KH Pham ND Ngyen HH Yamada S Muramoto Y Horimoto T Takada A Goto H Suzuki T Suzuki Y Kawaoka Y 《Nature》2005,437(7062):1108
The persistence of H5N1 avian influenza viruses in many Asian countries and their ability to cause fatal infections in humans have raised serious concerns about a global flu pandemic. Here we report the isolation of an H5N1 virus from a Vietnamese girl that is resistant to the drug oseltamivir, which is an inhibitor of the viral enzyme neuraminidase and is currently used for protection against and treatment of influenza. Further investigation is necessary to determine the prevalence of oseltamivir-resistant H5N1 viruses among patients treated with this drug. 相似文献
125.
Parvari R Hershkovitz E Grossman N Gorodischer R Loeys B Zecic A Mortier G Gregory S Sharony R Kambouris M Sakati N Meyer BF Al Aqeel AI Al Humaidan AK Al Zanhrani F Al Swaid A Al Othman J Diaz GA Weiner R Khan KT Gordon R Gelb BD;HRD/Autosomal Recessive Kenny-Caffey Syndrome Consortium 《Nature genetics》2002,32(3):448-452
The syndrome of congenital hypoparathyroidism, mental retardation, facial dysmorphism and extreme growth failure (HRD or Sanjad-Sakati syndrome; OMIM 241410) is an autosomal recessive disorder reported almost exclusively in Middle Eastern populations. A similar syndrome with the additional features of osteosclerosis and recurrent bacterial infections has been classified as autosomal recessive Kenny-Caffey syndrome (AR-KCS; OMIM 244460). Both traits have previously been mapped to chromosome 1q43-44 (refs 5,6) and, despite the observed clinical variability, share an ancestral haplotype, suggesting a common founder mutation. We describe refinement of the critical region to an interval of roughly 230 kb and identification of deletion and truncation mutations of TBCE in affected individuals. The gene TBCE encodes one of several chaperone proteins required for the proper folding of alpha-tubulin subunits and the formation of alpha-beta-tubulin heterodimers. Analysis of diseased fibroblasts and lymphoblastoid cells showed lower microtubule density at the microtubule-organizing center (MTOC) and perturbed microtubule polarity in diseased cells. Immunofluorescence and ultrastructural studies showed disturbances in subcellular organelles that require microtubules for membrane trafficking, such as the Golgi and late endosomal compartments. These findings demonstrate that HRD and AR-KCS are chaperone diseases caused by a genetic defect in the tubulin assembly pathway, and establish a potential connection between tubulin physiology and the development of the parathyroid. 相似文献
126.
Oaks JL Gilbert M Virani MZ Watson RT Meteyer CU Rideout BA Shivaprasad HL Ahmed S Chaudhry MJ Arshad M Mahmood S Ali A Khan AA 《Nature》2004,427(6975):630-633
127.
WajidRehman MusaKaleemBaloch BakhtiarMuhammad AminBadshah KhalidM.Khan 《科学通报(英文版)》2004,49(2):119-122
The synthesis and in vitro antifungal activity of some Schiff bases and their Sn (Ⅳ) complexes has been tested against plant pathogenic fungi and it is found that they possess excellent fungicidal activity. On the basis of ^1H-, ^13C-,^119Sn NMR-, ^119Sn Mǒssbauer, IR and Elemental analysis the tetrahedral geometry is proposed for the synthesized compounds. 相似文献
128.
Summary Wistar rats show a circadian variation in their response to stress. Pinealectomy exacerbates stress-induced gastric ulceration in rats. This effect is counteracted by melatonin administration. 相似文献
129.
T. R. Khan S. B. Singh R. K. Singh T. K. Singh 《Cellular and molecular life sciences : CMLS》1978,34(1):49-51
Summary The brain neurosecretory material is involved in the control of Corpora allata activity during post-embryonic development. A high concentration of neurosecretory material within the Corpora allata restrains the activity of the gland. 相似文献
130.
F. R. Khan M. Saleemuddin M. Siddiqi 《Cellular and molecular life sciences : CMLS》1976,32(5):551-552
Summary Removal of embryo axis before germination markedly prevents the development as well as subsequent decline in Flax cotyledon isocitritase. Cycloheximide inhibited the development and decline of the enzyme in intact cotyledons but prevented only the former in excised cotyledons.We thank Prof.W. Rahman, Head, Department of Chemistry for his interest and C.S.I.R. (India) for the award of Junior Research Fellowship to F.R.K. 相似文献