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501.
S. D. Kholkute Rohini P. Patil Meena P. Desai C. P. Puri 《Primates; journal of primatology》1988,29(4):549-555
Intramuscular administration of metachlopromide (2.5, 5, and 10 mg) induced a dose-dependent increase in plasma prolactin
levels. The magnitude and duration of metachlopromide-induced hyperprolactinemia were also dose related. However, metachlopromide
treatment (5 mg/day) for 60 days failed to affect ovarian function in the common marmoset as evidenced by ovulatory plasma
estradiol and progesterone profiles. During the pretreatment cycle, there was no consistent pattern in plasma prolactin levels
depending on the stage of cycle. During lactation, higher levels of plasma prolactin were observed. 相似文献
502.
503.
The membrane proteins of normal and hereditary spherocytosis have been labelled with a maleimide-analog nitroxide spin label and studied by electron paramagnetic resonance techniques. The spectral amplitude ratios from weakly and strongly immobilized labels differed slightly at 20° and 40°. Increasing the temperature to 47° and incubating for long time periods markedly accentuated the difference. It is suggested that the apparent differences in heat sensitivity between normal and hereditary spherocytosis erythrocyte membrane proteins reflect a latent structural alteration(s) of hereditary spherocytosis erythrocyte membrane proteins. Such structural alterations may result in altered functional behavior when the membrane is subjected to stress. 相似文献
504.
Capsular development and detailed morphology of exostructures of cowpeaRhizobium sp. JLn(c) were examined by transmission electron microscopy. The capsule development began at one pole in the form of polar fibrils in the early-exponential phase and extended further to cover the cell completely at the mid-exponential phase. Exostructures excreted by cowpeaRhizobium sp. JLn(c) have been found to be attached to cells or free in the culture medium; they consisted of mixtures of complex acidic exopolysaccharides (Type I) and neutral glucans (Type II). These polymers were separated by gel filtration and high-pressure liquid chromatography. The acidic microfibrils from JLn(c) were isolated and identified as cellulose by infrared spectral analysis. This acidic polymer was chemically characterized and was found to contain mainly glucose, galactose, glucuronic acid, mannose, fucose, pyruvate, acetate, and uronates. 相似文献
505.
506.
Mahesh Chhatbar Ramavatar Meena Kamalesh Prasad A.K. Siddhanta 《Carbohydrate polymers》2009,76(4):650-656
A rapid one-pot method for hydrolysis of sodium alginate for determining M/G ratio has been developed under mild conditions, using microwave irradiation. Poly-mannuronic acid (PMA) and poly-guluronic acid (PGA) ratio was determined (M/G 0.38), which was similar to that (M/G 0.39) obtained by the conventional method, using sodium alginate of Sigma as reference sample for bench marking. For validation of the method PMA and PGA were characterized by density, porosity, viscosity, optical rotation measurements, 13C NMR, FT-IR, thermogravimetric analysis (TGA), X-ray diffraction, circular dichroism (CD), molar mass distribution (GPC) and scanning electron microscopy (SEM). 相似文献
507.
Kimberly Stark Tatiana Goncharov Eugene Varfolomeev Luke Xie Hai Ngu Ivan Peng Keith R. Anderson Erik Verschueren Meena Choi Donald S. Kirkpatrick Amy Easton Joshua D. Webster Brent S. McKenzie Domagoj Vucic Baris Bingol 《Cell death & disease》2021,12(4)
RIP1 kinase-mediated inflammatory and cell death pathways have been implicated in the pathology of acute and chronic disorders of the nervous system. Here, we describe a novel animal model of RIP1 kinase deficiency, generated by knock-in of the kinase-inactivating RIP1(D138N) mutation in rats. Homozygous RIP1 kinase-dead (KD) rats had normal development, reproduction and did not show any gross phenotypes at baseline. However, cells derived from RIP1 KD rats displayed resistance to necroptotic cell death. In addition, RIP1 KD rats were resistant to TNF-induced systemic shock. We studied the utility of RIP1 KD rats for neurological disorders by testing the efficacy of the genetic inactivation in the transient middle cerebral artery occlusion/reperfusion model of brain injury. RIP1 KD rats were protected in this model in a battery of behavioral, imaging, and histopathological endpoints. In addition, RIP1 KD rats had reduced inflammation and accumulation of neuronal injury biomarkers. Unbiased proteomics in the plasma identified additional changes that were ameliorated by RIP1 genetic inactivation. Together these data highlight the utility of the RIP1 KD rats for target validation and biomarker studies for neurological disorders.Subject terms: Cell death in the nervous system, Diseases of the nervous system 相似文献
508.
A new flavanone glycoside 5-hydroxy-6,7,3′,4′,5′-pentamethoxyflavanone 5-O-α-l-rhamnopyranoside along with quercetagetin 3,6-dimethyl ether and an anthraquinone glycoside have been isolated from the stem bark of Cassia renigera. The two flavonoids were characterized by spectral and chemical studies. 相似文献
509.
Krishna Kumar Veeravalli Venkata Ramesh Dasari Andrew J. Tsung Dzung H. Dinh Meena Gujrati Dan Fassett Jasti S. Rao 《Neurochemical research》2009,34(7):1183-1194
We investigated the involvement of tPA after SCI in rats and effect of treatment with human umbilical cord blood derived stem
cells. tPA expression and activity were determined in vivo after SCI in rats and in vitro in rat embryonic spinal neurons
in response to injury with staurosporine, hydrogen peroxide and glutamate. The activity and/or expression of tPA increased
after SCI and reached peak levels on day 21 post-SCI. Notably, the tPA mRNA activity was upregulated by 310-fold compared
to controls on day 21 post-SCI. As expected, MBP expression is minimal at the time of peak tPA activity and vice versa. Implantation
of hUCB after SCI resulted in the downregulation of elevated tPA activity/expression in vivo in rats as well as in vitro in
spinal neurons. Our results demonstrated the involvement of tPA in the secondary pathogenesis after SCI as well as the therapeutic
potential of hUCB. 相似文献
510.
Diaminopimelate decarboxylase (EC 4.1.1.20) ofMicrococcus glutamicus ATCC 13059 was purified to homogeneity. The enzyme had an apparent molecular weight of 191,000 as determined by gel filtration
on Sephadex G-200. At protein concentrations of 20 and 10 μg per ml and in the absence of pyridoxal-5′-phosphate, it dissociated
into a species of molecular weight 94,000. The polypeptide chain molecular weight as determined by sodium dodecyl sulphate
Polyacrylamide gel electrophoresis was 100,000. TheK
m formeso diaminopimelate was 0.5 mM and that for pyridoxal-5′-phosphate was 0.6 μI. Sulphydryl groups and pyridoxal-5′-phosphate were
essential for activity and stability. The enzyme was inhibited significantly by L-lysine and DL-aspartic β-semialdehyde. 相似文献