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11.
Studies of paracrystal formation by column purified light meromyosin (LMM) prepared in a variety of ways led to the following conclusions: (a) different portions of the myosin rod may be coded for different stagger relationships. This was concluded from observations that paracrystals with different axial repeat periodicities could be obtained either with LMM framents of different lengths prepared with the same enzyme, or with LMM fragments of identical lengths but prepared with different enzymes. (b) Paracrystals with a 14-nm axial repeat periodicity are most likely formed by the aggregation of sheets with a 44-nm axial repeat within the sheets which are staggered by 14 nm. All of the axial repeat patterns expected from one sheet or aggregates of more than one sheet, on this basis, were observed in the same electron micrograph. (c) C-protein binding probably occurs preferentially to LMM molecules related in some specific way. This was concluded from the observation that the same axial repeat pattern was obtained in paracrystals formed from different LMM preparations in the presence of C-protein, regardless of differences in the axial repeat obtained in the absence of C-protein. (d) Nucleic acid is responsible for the 43-nm axial repeat patterns observed in paracrystals formed by the ethanol-resistant fraction of LMM. In the absence of nuclei acid, paracrystals with a 14nm axial repeat are obtained. (e) The 43-nm axial repeat pattern observed with the ethanol-resistant fraction of LMM is different for LMM preparations obtained by trypsin and papain digestions. 相似文献
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Background
In the backdrop of conflicting reports (some studies reported adverse outcomes of biomass fuel use whereas few studies reported absence of any association between adverse health effect and fuel use, may be due to presence of large number of confounding variables) on the respiratory health effects of biomass fuel use, this cross sectional survey was undertaken to understand the role of fuel use on pulmonary function.Method
This study was conducted in a village of western India involving 369 randomly selected adult subjects (165 male and 204 female). All the subjects were interviewed and were subjected to pulmonary function test. Analysis of covariance was performed to compare the levels of different pulmonary function test parameters in relation to different fuel use taking care of the role of possible confounding factors.Results
This study showed that biomass fuel use (especially wood) is an important factor for deterioration of pulmonary function (particularly in female). FEV1 (p < .05), FEV1 % (p < .01), PEFR (p < .05) and FEF25–75 (p < .01) values were significantly lower in biomass fuel using females than nonusers. Comparison of only biomass fuel use vs. only LPG (Liquefied Petroleum Gas) use and only wood vs. only LPG use has showed that LPG is a safer fuel so far as deterioration of pulmonary function is concerned. This study observes some deterioration of pulmonary function in the male subjects also, who came from biomass fuel using families.Conclusion
This study concluded that traditional biomass fuels like wood have adverse effects on pulmonary function. 相似文献13.
14.
Systems Biology involves the study of the interactions of biological systems and ultimately their functions. Down''s syndrome (DS)
is one of the most common genetic disorders which are caused by complete, or occasionally partial, triplication of chromosome 21,
characterized by cognitive and language dysfunction coupled with sensory and neuromotor deficits. Neural Tube Disorders
(NTDs) are a group of congenital malformations of the central nervous system and neighboring structures related to defective
neural tube closure during the first trimester of pregnancy usually occurring between days 18-29 of gestation. Several studies in the
past have provided considerable evidence that abnormal folate and methyl metabolism are associated with onset of DS & NTDs.
There is a possible common etiological pathway for both NTDs and Down''s syndrome. But, various research studies over the years
have indicated very little evidence for familial link between the two disorders. Our research aimed at the gene expression profiling
of microarray datasets pertaining to the two disorders to identify genes whose expression levels are significantly altered in these
conditions. The genes which were 1.5 fold unregulated and having a p-value <0.05 were filtered out and gene interaction network
were constructed for both NTDs and DS. The top ranked dense clique for both the disorders were recognized and over
representation analysis was carried out for each of the constituent genes. The comprehensive manual analysis of these genes yields
a hypothetical understanding of the lack of familial link between DS and NTDs. There were no genes involved with folic acid
present in the dense cliques. Only – CBL, EGFR genes were commonly present, which makes the allelic variants of these genes –
good candidates for future studies regarding the familial link between DS and NTDs.
Abbreviations
NTD - Neural Tube Disorders, DS - Down''s Syndrome, MTHFR - Methylenetetrahydrofolate reductase, MTRR– 5 - methyltetrahydrofolate-homocysteine methyltransferase reductase. 相似文献15.
Hong Lewis Z Hong Shuzhen Wong Han Teng Aw Pauline PK Cheng Yan Wilm Andreas de Sessions Paola F Lim Seng Gee Nagarajan Niranjan Hibberd Martin L Quake Stephen R Burkholder William F 《Genome biology》2014,15(11):1-14
Epidemiologists aim to inform the design of public health interventions with evidence on the evolution, emergence and spread of infectious diseases. Sequencing of pathogen genomes, together with date, location, clinical manifestation and other relevant data about sample origins, can contribute to describing nearly every aspect of transmission dynamics, including local transmission and global spread. The analyses of these data have implications for all levels of clinical and public health practice, from institutional infection control to policies for surveillance, prevention and treatment. This review highlights the range of epidemiological questions that can be addressed from the combination of genome sequence and traditional ‘line lists’ (tables of epidemiological data where each line includes demographic and clinical features of infected individuals). We identify opportunities for these data to inform interventions that reduce disease incidence and prevalence. By considering current limitations of, and challenges to, interpreting these data, we aim to outline a research agenda to accelerate the genomics-driven transformation in public health microbiology. 相似文献
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17.
Background
The tolerability and efficacy of single dose albendazole (400 mg), diethylcarbamazine citrate (DEC) (6 mg/kg bodyweight) or co-administration of albendazole (400 mg) + DEC (6 mg/kg bodyweight) was studied in 54 asymptomatic Wuchereria bancrofti microfilaraemic volunteers in a double blind hospital-based clinical study. 相似文献18.
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20.
A P Element Containing Suppressor of Hairy-Wing Binding Regions Has Novel Properties for Mutagenesis in Drosophila Melanogaster 总被引:4,自引:0,他引:4
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R. R. Roseman E. A. Johnson C. K. Rodesch M. Bjerke R. N. Nagoshi P. K. Geyer PK 《Genetics》1995,141(3):1061-1074
P elements are widely used as insertional mutagens to tag genes, facilitating molecular cloning and analyses. We modified a P element so that it carried two copies of the suppressor of Hairy-wing [su(Hw)] binding regions isolated from the gypsy transposable element. This transposon was mobilized, and the genetic consequences of its insertion were analyzed. Gene expression can be altered by the su(Hw) protein as a result of blocking the interaction between enhancer/silencer elements and their promoter. These effects can occur over long distances and are general. Therefore, a composite transposon (SUPor-P for suppressor-P element) combines the mutagenic efficacy of the gypsy element with the controllable transposition of P elements. We show that, compared to standard P elements, this composite transposon causes an expanded repertoire of mutations and produces alleles that are suppressed by su(Hw) mutations. The large number of heterochromatic insertions obtained is unusual compared to other insertional mutagenesis procedures, indicating that the SUPor-P transposon may be useful for studying the structural and functional properties of heterochromatin. 相似文献