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1.
The performance of The Subhuman Primate Pregnancy Test Kit was evaluated for routine detection of early (days 19-21) pregnancy in the rhesus monkey. Out of 123 confirmed matings, 19 resulted in pregnancy. In the pregnant animals the kit had an accuracy of 73.7%. In the nonpregnant females the accuracy was higher, 88.5%. False positives were encountered in ovariectomized females as well as adult intact males.  相似文献   
2.
The rotational motions of human fibrinogen in solution at 20 degrees C have been examined, in the 0.2-12-microseconds time range, by measuring the laser-induced dichroism of the triplet state of an erythrosin probe covalently bonded to the protein. The decay of the anisotropy was multiexponential, and up to three correlation times (phi 1 = 380 +/- 50 ns, phi 2 = 1.1 +/- 0.1 microseconds, and phi 3 = 3.3 +/- 0.6 microseconds) were needed to obtain a satisfactory analysis. The experimental data are consistent with the brownian motions of an elongated, rigid particle. If the correlation times are combined with previous data on the intrinsic viscosity of fibrinogen, the rotational and translational diffusive properties of the protein can be reproduced with high accuracy by idealizing it as an elongated ellipsoid of revolution with dimensions (2a x 2b) of (54 +/- 6) x (7.2 +/- 0.5) nm, having rotational diffusion constants of D parallel = (6.2 +/- 0.7) x 10(5) s-1 and D perpendicular = (5 +/- 1) x 10(4) s-1. The possibility of Ca(2+)-dependent changes in the rigidity or conformation of fibrinogen was excluded by examining the submicrosecond time-resolved fluorescence depolarization of 1-methylpyrene conjugates of the protein in the presence of different calcium concentrations. Although there are inherent difficulties to extrapolate the data on isolated fibrinogen molecules to the polymerizing species, this relatively stiff conformation meets the requirements of the classical half-staggered double-stranded model of fibrin polymerization rather better than those of the recently proposed interlocked single-stranded mechanism.  相似文献   
3.
A virus isolated from turnip in Aligarh, India, which caused mild mosaic, mottling and curling of leaves followed by overall stunting of plants, was characterized as potato virus X (PVX) on the basis of its host range, biological and physical properties, particle morphology, ultrastructural studies, and serological relationship.  相似文献   
4.
5.
Liver disorders may occur as a result of exposure to chemical compounds capable of inducing the oxidative stress and hepatic injuries. The aim of present study was to investigate the effects of flower extracts of B. Variegata for the treatment of liver injury induced by the CCl4. About 1 ml/kg body weight (b.w) of CCl4 was induced to experimental mice by intraperitoneal way for 14 days. The methanol and chloroform extracts (100, 200 and 300 mg/kg b.w) were administered to experimental animals for 14 days along with standard drug Silymarine (100 mg/kg b.w). The extracts alone showed no evidence of hepatic toxicity but animals exposed to CCl4 without the treatment with B. Variegata presented variations in levels of liver enzymes, antioxidant enzymes, proteins and blood cells as well as injuries in liver cells were also observed during histopathological study. However, after the treatments especially with 300 mg/kg b.w of methanol flower extracts levels of liver markers (ALT, AST and ALP), antioxidant enzymes and blood cells decreases and turned towards normal levels. Whereas level of total proteins and bilirubin was improved and damaged liver cells were repaired. The curative activity of flower extracts can be correlated to the higher potential of antioxidants and occurrence of Quercetin and some other organic compounds those were investigated from flower extracts of B. Variegata during HPLC and GC-MS analysis. The finding of this study supports the use of B. Variegata flower formulation in folk medicines.  相似文献   
6.
Exome sequencing coupled with homozygosity mapping was used to identify a transition mutation (c.794T>C; p.Leu265Ser) in ELMOD3 at the DFNB88 locus that is associated with nonsyndromic deafness in a large Pakistani family, PKDF468. The affected individuals of this family exhibited pre-lingual, severe-to-profound degrees of mixed hearing loss. ELMOD3 belongs to the engulfment and cell motility (ELMO) family, which consists of six paralogs in mammals. Several members of the ELMO family have been shown to regulate a subset of GTPases within the Ras superfamily. However, ELMOD3 is a largely uncharacterized protein that has no previously known biochemical activities. We found that in rodents, within the sensory epithelia of the inner ear, ELMOD3 appears most pronounced in the stereocilia of cochlear hair cells. Fluorescently tagged ELMOD3 co-localized with the actin cytoskeleton in MDCK cells and actin-based microvilli of LLC-PK1-CL4 epithelial cells. The p.Leu265Ser mutation in the ELMO domain impaired each of these activities. Super-resolution imaging revealed instances of close association of ELMOD3 with actin at the plasma membrane of MDCK cells. Furthermore, recombinant human GST-ELMOD3 exhibited GTPase activating protein (GAP) activity against the Arl2 GTPase, which was completely abolished by the p.Leu265Ser mutation. Collectively, our data provide the first insights into the expression and biochemical properties of ELMOD3 and highlight its functional links to sound perception and actin cytoskeleton.  相似文献   
7.
Six bioactive compounds were isolated from the seeds extract of Piper nigrum Linn. following a larvicidal activity guided isolation against 4th instar larvae of Aedes aegypti L., a Dengue vector mosquito and a carrier of yellow fever. Their structures were elucidated using spectroscopic methods including HR-EI-MS, FAB-MS, 1H and 13C NMR (Broad Bond Decoupled, & DEPT), and 2D-NMR techniques (1H–1H COSY, NOESY, HMQC, HMBC, & 2D-J-resolved). These include three new constituents namely pipilyasine (1), pipzubedine (2) and pipyaqubine (3), and three known constituents pellitorine (4), pipericine (5) and piperine (6). The larvicidal activity was determined by WHO method.  相似文献   
8.
Mughees  Mohd  Chugh  Himanshu  Wajid  Saima 《Protoplasma》2020,257(2):345-352
Protoplasma - Vesicular trafficking between endoplasmic reticulum and Golgi plays a major role in the growth and proliferation of breast cancer cells. Various proteins regulate this ER-Golgi...  相似文献   
9.
Haider  Saida  Sajid  Irfan  Batool  Zehra  Madiha  Syeda  Sadir  Sadia  Kamil  Noor  Liaquat  Laraib  Ahmad  Saara  Tabassum  Saiqa  Khaliq  Saima 《Neurochemical research》2020,45(11):2762-2774

Noise has always been an important environmental factor that induces health problems in the general population. Due to ever increasing noise pollution, humans are facing multiple auditory and non-auditory problems including neuropsychiatric disorders. In modern day life it is impossible to avoid noise due to the rapid industrialization of society. Continuous exposure to noise stress creates a disturbance in brain function which may lead to memory disorder. Therefore, it is necessary to find preventive measures to reduce the deleterious effects of noise exposure. Supplementation of taurine, a semi essential amino acid, is reported to alleviate psychiatric disorders. In this study noise-exposed (100 db; 3 h daily for 15 days) rats were supplemented with taurine at a dose of 100 mg/kg for 15 days. Spatial and recognition memory was assessed using the Morris water maze and novel object recognition task, respectively. Results of this study showed a reversal of noise-induced memory impairment in rats. The derangements of catecholaminergic and serotonergic levels in the hippocampus and altered brain antioxidant enzyme activity due to noise exposure were also restored by taurine administration. This study highlights the importance of taurine supplementation to mitigate noise-induced impaired memory via normalizing the neurochemical functions and reducing oxidative stress in rat brain.

  相似文献   
10.
Abstract

Acinetobacter baumannii is a biofilm forming multidrug resistant (MDR) pathogen responsible for respiratory tract infections. In this study, aluminium oxide nanoparticles (Al2O3 NPs) were synthesized and characterized by TEM and EDX and shown to be spherical shaped nanoparticles with a diameter < 10?nm. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) for the Al2O3 NPs ranged between 125 and 1,000?µg ml?1. Exposure to NPs caused cellular membrane disruption, indicated by an increase in cellular leakage of the contents. Biofilm inhibition was 11.64 to 70.2%, whereas attachment of bacteria to polystyrene surfaces was reduced to 48.8 to 51.9% in the presence of NPs. Nanoparticles also reduced extracellular polymeric substance production and the biomass of established biofilms. The data revealed the non-toxic nature of Al2O3 NPs up to a concentrations of 120?µg ml?1 in HeLa cell lines. These results demonstrate an effective and safer use of Al2O3 NPs against the MDR A. baumannii by targeting biofilm formation, adhesion and EPS production.  相似文献   
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