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81.
82.
Calligonolides A (1) and B (2), two new butanolides, and a new steroidal ester, 3, have been isolated from the whole plant of Calligonum polygonoides, together with four known compounds, tetracosan-4-olide, beta-sitosterol and its glucoside, and ursolic acid. Their structures were elucidated by spectroscopic and mass-spectrometric studies. Compounds 1-3 showed moderate inhibitory potential against lipoxygenase from soybean. 相似文献
83.
Seeking causes: Classifying and evaluating congenital heart defects in etiologic studies 总被引:1,自引:0,他引:1
Botto LD Lin AE Riehle-Colarusso T Malik S Correa A;National Birth Defects Prevention Study 《Birth defects research. Part A, Clinical and molecular teratology》2007,79(10):714-727
BACKGROUND: Classification and analysis of congenital heart defects (CHD) in etiologic studies is particularly challenging because of diversity of cardiac phenotypes and underlying developmental mechanisms. We describe an approach to classification for risk assessment of CHD based on developmental and epidemiologic considerations, and apply it to data from the National Birth Defect Prevention Study (NBDPS). METHODS: The classification system incorporated the three dimensions of cardiac phenotype, cardiac complexity, and extracardiac anomalies. The system was designed to facilitate the assessment of simple isolated defects and common associations. A team with cardiologic expertise applied the system to a large sample from the NBDPS. RESULTS: Of the 4,703 cases of CHDs in the NBDPS with birth years 1997 through 2002, 63.6% were simple, isolated cases. Specific associations of CHDs represented the majority of the remainder. The mapping strategy generated relatively large samples for most cardiac phenotypes and provided enough detail to isolate important subgroups of CHDs that may differ by etiology or mechanism. CONCLUSIONS: Classification of CHDs that considers cardiac and extracardiac phenotypes is practically feasible, and yields manageable groups of well-characterized phenotypes. Although best suited for large studies, this approach to classification and analysis can be a flexible and powerful tool in many types of etiologic studies of heart defects. 相似文献
84.
Sukhadeo Baliram Barbuddhe Deepak Bhiwa Rawool Swapnil Prakash Doijad Jess Vergis Satyaveer Singh Malik Trinad Chakraborty 《Environmental microbiology》2022,24(6):2759-2780
Listeria monocytogenes, the causative agent of listeriosis, has been implicated in increasing foodborne outbreaks worldwide. The disease is manifested in various forms ranging from severe sepsis in immune-compromised individuals, febrile gastroenteritis, still birth, abortions and meningoencephalitis. In India, data from studies on the detection and molecular epidemiological analysis of L. monocytogenes are only recently emerging. The presence of Listeria in different ecological niches has been recorded from India, including foods, soil, vegetables, mangrove swamps, seafood, freshwater fishes, clinical cases, and also insects. The organism has also been isolated from women with spontaneous abortions, miscarriage or recurrent obstetric history, aborted foetuses, animal clinical cases and wildlife samples. A novel species of Listeria has also been characterized. Listeria monocytogenes strains isolated from clinical, environmental, and foods showed biofilm-forming abilities. Listeria monocytogenes serotype 4b isolates of ST328, a predominant and unique ST observed in India, was repeatedly isolated from different sources, times, and geographical locations. Here, we reviewed the occurrence of Listeria in different sources in India, its resistance to biocides, and provide epidemiological analysis on its genomic landscape. 相似文献
85.
Javed Muhammad Umar Javaid Nadeem Malik Muhammad Waseem Akbar Mariam Samuel Omaji Yahaya Adamu Sani Othman Jalel Ben 《Cluster computing》2022,25(3):1839-1867
Cluster Computing - In this study, a secure and coordinated blockchain based energy trading system for Electric Vehicles (EVs) is presented. The major goals of this study are to provide secure and... 相似文献
86.
Faizan Q. Siddiqui Farnaz Malik F. R. Y. Fazli 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1995,666(2)
A rapid, sensitive and specific high-performance liquid chromatographic method was developed for the determination of serum levels of retinol in humans. A direct serum injection technique after deproteinisation was used to avoid lengthy pretreatment steps which can result in degradation of retinol during analysis. The column used was CLC-ODS, the mobile phase was acetonitrile-water and detection wavelength was 328 nm. Deterioration in column performance was not observed even after injection of 300 samples. The lower detection limit was 10 μg/l. On analyzing a serum pool six times, a C.V of 0.7% was obtained. The method is quantitative, reproducible, rapid and highly accurate for routine analysis. 相似文献
87.
S. Parvez M. I. Rajoka M. N. Ahmed F. Latif R. Shahid K. A. Malik 《Folia microbiologica》1998,43(1):59-62
Citric acid production from sugar cane molasses byAspergillus niger NIAB 280 was studied in a batch cultivation process. A maximum of 90 g/L total sugar was utilized in citric acid production
medium. From the parental strainA. niger, mutant strains showing resistance to 2-deoxyglucose in Vogal's medium containing molasses as a carbon source were induced
by γ-irradiation. Among the new series of mutant strains, strain RP7 produced 120 g/L while the parental strain produced 80
g/L citric acid (1.5-fold improvement) from 150 g/L of molasses sugars. The period of citric acid production was shortened
from 10 d for the wild-type strain to 6–7 d for the mutant strain. The efficiency of substrate uptake rate with respect to
total volume substrate consumption rate,Q
s (g per L per h) and specific substrate consumption rate,q
s (g substrate per g cells per h) revealed that the mutant grew faster than its parent. This indicated that the selected mutant
is insensitive to catabolite repression by higher concentrations of sugars for citric acid production. With respect to the
product yield coefficient (Y
p/x), volume productivity (Q
p) and specific product yields (q
p), the mutant strain is significantly (p≤0.05) improved over the parental strain. 相似文献
88.
Mehta D Ahmmed GU Paria BC Holinstat M Voyno-Yasenetskaya T Tiruppathi C Minshall RD Malik AB 《The Journal of biological chemistry》2003,278(35):33492-33500
We tested the hypothesis that RhoA, a monomeric GTP-binding protein, induces association of inositol trisphosphate receptor (IP3R) with transient receptor potential channel (TRPC1), and thereby activates store depletion-induced Ca2+ entry in endothelial cells. We showed that RhoA upon activation with thrombin associated with both IP3R and TRPC1. Thrombin also induced translocation of a complex consisting of Rho, IP3R, and TRPC1 to the plasma membrane. IP3R and TRPC1 translocation and association required Rho activation because the response was not seen in C3 transferase (C3)-treated cells. Rho function inhibition using Rho dominant-negative mutant or C3 dampened Ca2+ entry regardless of whether Ca2+ stores were emptied by thrombin, thapsigargin, or inositol trisphosphate. Rho-induced association of IP3R with TRPC1 was dependent on actin filament polymerization because latrunculin (which inhibits actin polymerization) prevented both the association and Ca2+ entry. We also showed that thrombin produced a sustained Rho-dependent increase in cytosolic Ca2+ concentration [Ca2+]i in endothelial cells overexpressing TRPC1. We further showed that Rho-activated Ca2+ entry via TRPC1 is important in the mechanism of the thrombin-induced increase in endothelial permeability. In summary, Rho activation signals interaction of IP3R with TRPC1 at the plasma membrane of endothelial cells, and triggers Ca2+ entry following store depletion and the resultant increase in endothelial permeability. 相似文献
89.
ANALYSIS OF MITOCHONDRIAL DNA DIVERSITY WITHIN AND BETWEEN NORTH AND SOUTH ATLANTIC RIGHT WHALES 总被引:1,自引:0,他引:1
DNA sequences of the mitochondrial control region of 180 North Atlantic right whales ( Euhalaena glacialis ) and 16 South Atlantic right whales ( E. australis ) have been determined using a combination of direct DNA sequencing and single stranded conformation polymorphism (SSCP) analysis. Five haplotypes were found in E. glacialis , and 10 in E. australis , but none were shared, supporting the reproductive isolation and separate species status of the North and South Atlantic right whales. One haplotype in E, glacialis was found in only three males born before 1982 and this matriline will likely be lost soon. The nucleotide diversity estimates for the five North Atlantic right whale haplotypes was 0.6% and 2.0% for the 10 haplotypes found in the South Atlantic right whales. The average haplotypic diversity was 0.87 in E. glacialis and 0.96 in E. australis , which is consistent with other studies showing a lower level of genetic variation in the North Atlantic right whale. Phylogenetic analysis identified two major assemblages of haplotypes in E. australis from the samples collected from Peninsula Valdes, suggesting a mixing of two historically divergent populations. Using genetic distance measurements with a divergence rate of 0.5%–1.0%/myr, we estimate E. glacialis diverged from E. australis 3–12.5 mya. 相似文献
90.
Mehnaz S Mirza MS Haurat J Bally R Normand P Bano A Malik KA 《Canadian journal of microbiology》2001,47(2):110-117
The present study deals with the isolation of plant growth promoting rhizobacteria (PGPR) from rice (variety NIAB IRRI-9) and the beneficial effects of these inoculants on two Basmati rice varieties. Nitrogen-fixing activity (acetylene-reduction activity) was detected in the roots and submerged shoots of field-grown rice variety NIAB IRRI-9. Estimation of the population size of diazotrophic bacteria by ARA-based MPN (acetylene reduction assay-based most probable number) in roots and shoots indicated about 10(5)-10(6) counts/g dry weight at panicle initiation and grain filling stages. Four bacterial isolates from rice roots and shoots were obtained in pure culture which produced phytohormone indoleacetic acid (IAA) in the growth medium. Among these, three isolates S1, S4, and R3 reduced acetylene to ethylene in nitrogen-free semi-solid medium. Morphological and physiological characteristics of the isolates indicated that three nitrogen-fixing isolates S1, S4, and R3 belonged to the genus Enterobacter, while the non-fixing isolate R8 belonged to the genus Aeromonas. 16S rRNA sequence of one isolate from root (R8) and one isolate from shoot (S1) was obtained which confirmed identification of the isolates as Aeromonas veronii and Enterobacter cloacae, respectively. The 1517-nucleotide-long sequence of the isolate R8 showed 99% similarity with Aeromonas veronii (accession No. AF099023) while partial 16S rRNA sequence (two stretches of total 1271 nucleotide length) of S1 showed 97% similarity with the sequence of Enterobacter cloacae (accession No. AJ251469). The seedlings of two rice varieties Basmati 385 and Super Basmati were inoculated with the four bacterial isolates from rice and one Azospirillum brasilense strain Wb3, which was isolated from wheat. In the rice variety Basmati 385, maximum increase in root area and plant biomass was obtained in plants inoculated with Enterobacter S1 and Azospirillum Wb3, whereas in the rice variety Super Basmati, inoculation with Enterobacter R3 resulted in maximum increase of root area and plant biomass. Nitrogen fixation was quantified by using 15N isotopic dilution method. Maximum fixation was observed in Basmati 385 with the inoculants Azospirillum Wb3 and Enterobacter S1 where nearly 46% and 41% of the nitrogen was derived from atmosphere (%Ndfa), respectively. In general, higher nitrogen fixation was observed in variety Basmati 385 than in Super Basmati, and different bacterial strains were found more effective as inoculants for the rice varieties Basmati 385 and Super Basmati. 相似文献