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191.
P. Speckart M. Golub P. Zia R. Zipser R. Horton 《Prostaglandins & other lipid mediators》1976,11(3):481-488
The effect of angiotensin II on peripheral levels of immunoreactive prostaglandin A2 (IR-PGA) was determined in 17 normal male volunteers. IR-PGA rose from 338 ± 65 (SE) pg/ml to 635 ± 142 in response to pressor infusions of angiotensin II (p <0.05 on paired analysis). This increase was not observed when indomethacin, 75 mg p.o., was given to 8 patients two hours prior to a repeat infusion. Five patients of the original group were placed on a low sodium diet (10–20 mEq). The response to angiotensin was now exaggerated (278 ±52 pg/ml to 916 ± 284). These five patients were kept on a low sodium intake and given indomethacin 50 mg p.o. q 6 hourly for 4 days. There was no significant rise with angiotensin infusion (106 ± 31 pg/ml to 120 ± 70). Pressor infusions of angiotensin II raise peripheral levels of IR-PGA, and this response is exaggerated by a low sodium diet and blocked by either acute or chronic indomethacin administration. This data supports the concept that vasodilatory prostaglandins may be released by endogenous angiotensin and thus provide a dynamic antagonism to the renin angiotensin system in man. 相似文献
192.
Michael S. Golub Priscilla K. Zia Richard Horton 《Prostaglandins & other lipid mediators》1974,8(1):13-20
The effect of human blood on prostaglandin metabolism in vitro was studied at 37°C and 4°C. Labeled prostaglandins were incubated for up to one hour in whole blood or plasma. After extraction, the prostaglandins were purified by LH-20 Sephadex chromatography. Appropriate 14C labeled compounds, when available, were used to correct for losses. Metabolism was determined by comparison of incubated samples with zero time controls. There was no reduction in isotopic recovery of prostaglandins B1, B2 and E1 after incubation with whole blood for up to one hour. In contrast, human whole blood, but not plasma, rapidly metabolized prostaglandins A1 and A2 at 37°C. The rate of metabolism was temperature dependent, but still continued at 4°C. The products of these reactions were not identified, but they appeared to remain in the aqueous solution after extraction with the neutral organic solvent. 相似文献
193.
Hossein Zia Woodrow J. Proveaux John P. ODonnell Joseph K.H. Ma 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1980,181(1):77-84
A simple and accurate assay for the determination of griseofulvin and its metabolites in biological fluids using high-performance liquid chromatography is described. Using a reversed phase column and a mobile phase solvent of 45% acetonitrile in 0.1 M acetic acid, baseline separation of griseofulvin and several analogues was obtained. The described method allows one to quantitatively determine griseofulvin, 6-demethylgriseofulvin, and griseofulvic acid, a newly identified metabolite in man, in urine and plasma samples. Treatment of plasma samples prior to the analysis is simply made by deproteinizing the samples with an equal volume of acetonitrile. For urine samples, the procedure involves diethyl ether extraction with subsequent evaporation to dryness and reconstitution with the mobile phase solvent. 相似文献
194.
A study of the freshwater rotifer Brachionus calyciflorus in Pekanbaru, Riau, Indonesia 总被引:1,自引:0,他引:1
Tengku Dahril 《Hydrobiologia》1997,358(1-3):211-215
Brachionus calyciflorus is one of freshwaterrotifers found in fish ponds in Pekanbaru, Riau,Indonesia. Its density varied depending on that ofphytoplankton. Maximum of 2.5 ×103 ind. l–1 was found in ponds fertilised with animal wastes.The fecundity and population growth of B.calyciflorus was studied. Results indicated that the fecundity of amictic females was higher thanthat of unfertilized mictic females. During their life span, amictic and mictic females produced29.7 and 12.5 eggs per female, respectively. In the mass culture of 500 ml media, the highestdensity of female and male rotifers was 975.8 and 9.6 ind. ml–1, respectively. During 8 days cultureperiod, they also produced eggs as many as 124.2 ml–1.Human and animal wastespromoted the growth of phytoplankton as food forrotifers in the pond. A laboratory study confirms this. The best growth of B. calyciflorus at a density of 109 ind. ml–1 was found at 0.5 g l–1 of humanexcreta. A high density of B. calyciflorus (542ind. ml–1) was also found in semi-continuous culturewith chicken excreta. 相似文献
195.
Sudha Chaturvedi Harbans S. Randhawa Vishnu P. Chaturvedi Zia U. Khan 《Mycopathologia》1991,116(2):87-96
The efficacy of 20 seed-based media is reported for the in vitro mould-yeast conversion of Blastomyces dermatitidis, employing pharmamedia agar, peptone glucose agar, glucose agar and water agar as controls. The mould-yeast conversion varied significantly according to the culture medium, fungal strains and incubation period (p<0.01). Garden-pea, chick-pea, cow-pea, soyabean, peanut, green gram, French bean, lentil, okra and cottonseed converted all of the 7 B. dermatitidis test strains after 5 days of incubation at 37 ° C. Although the efficacy of many of these seed media was found to be at par with pharmamedia agar — a commercial cottonseed embryo-derived protein, garden-pea seed agar is adopted because of the wider availability and low fat content of this seed. The recommended composition of the medium comprises 2% aqueous seed extract, 2% glucose and pH 6–7. Only nigerseed and sunflower seeds failed to support the conversion of B. dermatitidis. Of the control media, peptone glucose agar, glucose agar and water agar did not support the conversion of 2 of the B. dermatitidis test strains. The mechanism underlying variable mould-yeast conversion of B. dermatitidis on seed-based media is not clearly understood. However, most of the seeds supporting excellent mould-yeast conversion are known for their high protein content. The conversion was apparently not affected by the fat content of the seeds or by incorporation of glucose in the medium. 相似文献
196.
Zia KM Bhatti IA Barikani M Zuber M Sheikh MA 《International journal of biological macromolecules》2008,43(2):136-141
Chitin-based polyurethane elastomers (PUEs) were synthesized by step growth polymerization techniques using poly(epsilon-caprolactone) (PCL) varying diisocyanate and chain extender structures. The viscosity average molecular weight (M(v)) of chitin was deduced from the intrinsic viscosity and found; M(v)=6.067 x 10(5). The conventional spectroscopic characterization of the samples with FTIR, (1)H NMR and (13)C NMR were in accordance with proposed PUEs structure. The crystalline behavior of the synthesized polymers were investigated by X-ray diffraction (XRD), differential scanning calorimetery (DSC) and loss tangent curves (tan delta peaks). The observed patterns of the crystalline peaks for the lower angle for chitin in the 2theta range were indexed as 9.39 degrees, 19.72 degrees, 20.73 degrees, 23.41 degrees and 26.39 degrees. Results showed that crystallinity of the synthesized PUEs samples was affected by varying the structure of the diisocyanate and chain extender. Crystallinity decreased from aliphatic to aromatic characters of the diisocyanates used in the final PU. The presence of chitin also favors the formation of more ordered structure, as higher peak intensities was obtained from the PU extended with chitin than 1,4-butane diol (BDO). The value of peak enthalpy (DeltaH) of chitin was found to be 47.13 J g(-1). The higher DeltaH value of 46.35 J g(-1) was found in the samples extended with chitin than BDO (39.73 J g(-1)). 相似文献
197.
The new variety of Actinomucor elegans var. kuwaitiensis, isolated from an open necrotic wound of a diabetic patient is described. This strain differed from the two previously described varieties of A. elegans, A. elegans var. elegans and A. elegans var. meitauzae by nearly 1% or more sequence divergence within D1/D2 regions of 28S rRNA and the ITS region of rRNA genes. Like the other two varieties, no zygospores were observed, however, there was evidence suggesting intersexual diploidy, a feature not described previously in this species. Additionally, A. elegans var. kuwaitiensis was pathogenic to white mice causing 100% mortality within 5 days. 相似文献
198.
Gulam Nabi MALIK Syed Zia Ul Haque RUFAIE Tejender Paul SINGH Mohammed Farooq BAQUAL Habib Ullah DAR 《昆虫学报》2005,48(6):982-985
采用完全随机设计法根据10头老熟幼虫体重、全茧重、茧层量、茧层率(%)、存活率、万蚕茧层量和茧丝长等指标,对两对二化性家蚕Bombyx mori L. 杂交品系(SH6×NB4D2和CSR2×CSR4)杂交一代的22个子代个体进行了遗传参数估算,以缩小优质蚕品种的候选范围,并且计算出直接筛选的参数,如遗传力和遗传进度等,使这些信息可用于以筛选高产新品种为目的的育种和选择过程中。杂交子代2, 4, 5, 6, 7, 10, 14, 16, 19和20号个体在这几个指标中表现出显著的优越性。全茧重、万蚕茧层量和茧丝长的遗传力和遗传进度较大,可以简单地从表现型的差异对这些性状进行选择并取得遗传性状改良。其他几个指标(10头老熟幼虫体重、茧层量、茧层率(%)和存活率)的遗传力和遗传进度较低,对这些性状进行直接选择来改良品种的效果较差。 相似文献
199.
A novel peroxidase isolated from a local chick pea (Cicer arietinum L.) cultivar (Balksar 2000) was purified by means of ammonium sulfate precipitation, DEAE-cellulose chromatography and two runs on gel filtration. The purified enzyme has a specific activity of 2045 U/mg with 17 % activity recovery. The molecular mass of the enzyme was estimated to be 39 kDa by SDS-polyacrylamide gel electrophoresis. Optimum pH and temperature of the enzyme were 5.5 and 45 degrees C respectively. The thermal denaturation of local chick pea peroxidase was studied in aqueous solution at temperatures ranging from 45 degrees C to 65 degrees C. The temperature of 50% inactivation of the enzyme was found to be 68 degrees C. The enthalpy (DeltaH*) and free energy (DeltaG*) of thermal denaturation of chick pea peroxidase were 101.4 and 103.4 k J/mol respectively at 65 degrees C.Metals like Zn2+, Mn2+, Hg2+, Co2+ and Al3+ slightly inhibited the peroxidase activity while Ca2+, Mg2+ and Ba2+ have no effect on enzyme activity. The high specific activity and thermal stability make chick pea peroxidase an alternative to horseradish peroxidase (HRP) in various applications. 相似文献
200.
Plasma homocysteine and DNA damage profiles in normal and obese subjects in the Pakistani population
Shazia A. Bukhari Muhammad I. Rajoka Saeed A. Nagra Zia Ur Rehman 《Molecular biology reports》2010,37(1):289-295
Dependence of plasma total homocysteine (tHcy) and DNA damage profiles on melanodialdehyde (MDA), oxidative stress, liver
function tests (LFT), and lipids was studied in non-obese and obese subjects in the Pakistani population. Development of obesity
is influenced by both genetic, biochemical and environmental factors. Plasma homocysteine (Hcy) and DNA damage profiles play
a pivotal role in its progression. We studied 160 obesity patients and 160 lean subjects. Leukocytes were evaluated for DNA
damage by comet assay and blood plasma for biochemical properties using commercial kits. Plasma Hcy level and DNA damage were
strongly correlated with triglycerides (P < 0.000), LDL-cholesterol (P < 0.001), systolic blood pressure (P < 0.001), cholesterol (P < 0.004), MDA (P < 0.004) and total oxygen stress (P < 0.004) in obese individuals. Both Hyc and DNA damage were negatively associated with total anti-oxidant response and globulin.
Both Hcy profile and DNA damage may have a role in the endothelium damage even in the normal range and are related to triglycerides,
ALT, MDA, TOS, HDL- and LDL-cholesterol in the Pakistani population. 相似文献