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排序方式: 共有355条查询结果,搜索用时 15 毫秒
111.
Rauch A Thiel CT Schindler D Wick U Crow YJ Ekici AB van Essen AJ Goecke TO Al-Gazali L Chrzanowska KH Zweier C Brunner HG Becker K Curry CJ Dallapiccola B Devriendt K Dörfler A Kinning E Megarbane A Meinecke P Semple RK Spranger S Toutain A Trembath RC Voss E Wilson L Hennekam R de Zegher F Dörr HG Reis A 《Science (New York, N.Y.)》2008,319(5864):816-819
Fundamental processes influencing human growth can be revealed by studying extreme short stature. Using genetic linkage analysis, we find that biallelic loss-of-function mutations in the centrosomal pericentrin (PCNT) gene on chromosome 21q22.3 cause microcephalic osteodysplastic primordial dwarfism type II (MOPD II) in 25 patients. Adults with this rare inherited condition have an average height of 100 centimeters and a brain size comparable to that of a 3-month-old baby, but are of near-normal intelligence. Absence of PCNT results in disorganized mitotic spindles and missegregation of chromosomes. Mutations in related genes are known to cause primary microcephaly (MCPH1, CDK5RAP2, ASPM, and CENPJ). 相似文献
112.
Bais MV Kataria RS Tiwari AK Viswas KN Reddy AV Prasad N 《Veterinary research communications》2004,28(7):641-646
Veterinary Research Communications - 相似文献
113.
Tews I Findeisen F Sinning I Schultz A Schultz JE Linder JU 《Science (New York, N.Y.)》2005,308(5724):1020-1023
Class III adenylyl cyclases contain catalytic and regulatory domains, yet structural insight into their interactions is missing. We show that the mycobacterial adenylyl cyclase Rv1264 is rendered a pH sensor by its N-terminal domain. In the structure of the inhibited state, catalytic and regulatory domains share a large interface involving catalytic residues. In the structure of the active state, the two catalytic domains rotate by 55 degrees to form two catalytic sites at their interface. Two alpha helices serve as molecular switches. Mutagenesis is consistent with a regulatory role of the structural transition, and we suggest that the transition is regulated by pH. 相似文献
114.
Wentworth P McDunn JE Wentworth AD Takeuchi C Nieva J Jones T Bautista C Ruedi JM Gutierrez A Janda KD Babior BM Eschenmoser A Lerner RA 《Science (New York, N.Y.)》2002,298(5601):2195-2199
Recently, we showed that antibodies catalyze the generation of hydrogen peroxide (H2O2) from singlet molecular oxygen (1O2*) and water. Here, we show that this process can lead to efficient killing of bacteria, regardless of the antigen specificity of the antibody. H2O2 production by antibodies alone was found to be not sufficient for bacterial killing. Our studies suggested that the antibody-catalyzed water-oxidation pathway produced an additional molecular species with a chemical signature similar to that of ozone. This species is also generated during the oxidative burst of activated human neutrophils and during inflammation. These observations suggest that alternative pathways may exist for biological killing of bacteria that are mediated by potent oxidants previously unknown to biology. 相似文献
115.
Anita Losonczi George Szakacs Emilia Csiszar Outi Kareela 《浙江大学学报(农业与生命科学版)》2004,30(4):437-437
Preparation and bleaching are among the most energy and chemical intensive steps of the traditional cotton finishing. About 75% of the organic pollutants arising from textile finishing are derived from the preparation of cotton goods. Biopreparation may be a valuable and environmentally friendly alternative to harsh alkaline chemicals for preparing of cotton. Different enzymes i.e. cellulases, pectinases, lipases and proteases have been tested for biopreparation. Many papers have been publishe… 相似文献
116.
Grain hardness is one of the most important quality characteristics of cultivated bread wheat (Triticum aestivum L.). A large deletion in the puroindoline a (Pina) gene or single nucleotide polymorphisms (SNPs) in the puroindoline b (Pinb) gene results in hard grain texture. So far, nine Pina alleles (Pina-D1a–Pina-D1b, Pina-D1k–Pina-D1q) and seventeen Pinb alleles (Pinb-D1a–Pinb-D1g, Pinb-D1p–Pinb-D1ab) have been identified in bread wheat. The major Pina and Pinb alleles identified in hard wheat cultivars are Pina-D1b, Pinb-D1b, Pinb-D1c and Pinb-D1d. In this study, a three-primer PCR system was employed to develop nine co-dominant STS markers for genotyping Pina-D1a and Pina-D1b, whereas temperature-switch (TS) PCR was used to develop six co-dominant SNP markers for genotyping the Pinb-D1a, Pinb-D1b, Pinb-D1c and Pinb-D1d alleles. These STS and TS-PCR markers were used to verify the grain hardness genotype of 100 wheat cultivars. The reliability and genotyping accuracy of TS-PCR markers were confirmed through sequencing of PCR products and a comparison with previously published results. Therefore, STS and TS-PCR markers offer a simple, cost-effective and reliable method for high-throughput genotyping Pina and Pinb alleles to select grain hardness in wheat quality breeding programs and for wheat market classification. 相似文献
117.
Ethanol production from agro-waste provides an alternative energy-production system. Statistical experimental designs were used for optimization of critical nutrients and process variables for ethanol production. The critical nutrients and process variables were initially selected according to a Placket-Burman (PB) design. Selected factors (inoculum level 1-5%, pH 4.5-7, temperature 25-35 °C and urea concentration 0.25-0.75 g/L) were optimized by response surface methodology (RSM) based on a three-level four-factor Box-Behnken design (BBD). Under optimum conditions of inoculum level 3%, pH 5.75, temperature 30 °C and urea concentration 0.50 g/L maximum ethanol production obtained 13.2 g/L from microwave alkali pretreated rice straw with ethanol productivity 0.33 g/L/h. Under optimum conditions ethanol production studied at fermenter level and obtained ethanol concentration 19.2 g/L, ethanol productivity 0.53 g/L/h and ethanol yield to consumed sugar 0.50 g/g. These results indicated that ethanol production can be enhanced by optimization of nutritional and process variables. 相似文献
118.
119.
Tiwari AK Kataria RS Indervesh Prasad N Gupta R 《Comparative immunology, microbiology and infectious diseases》2003,26(1):47-53
In order to differentiate infectious bursal disease virus (IBDV) isolates/strains, a quick method of RT-PCR followed by restriction enzyme analysis of VP1 gene sequence is being reported for the first time. A 480 bp fragment, comprising one of the RNA dependent RNA polymerase motifs of VP1 gene sequence of an Indian classical virus, an attenuated vaccine strain, Georgia and two Indian field isolates, genetically similar to reported very virulent strains of IBDV, was amplified by RT-PCR. Restriction enzyme digestion of PCR products with Taq1 enzyme generated distinct profile for field isolates, different from the classical and attenuated viruses, whereas restriction profile with BstNI restriction enzyme was similar in all the viruses, irrespective of the pathotype. Therefore, the present results suggest that Taq1 digestion can be taken up for the differentiation of field isolates from the classical and vaccine strains. The sequence analysis of VPI gene of reported very virulent IBD viruses from Europe and Japan, using 'MapDraw' programme of Lasergene software, revealed similar restriction enzyme profile as in Indian field isolates. 相似文献
120.