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131.
Cirrhosis of the liver has no effect upon the incidence of carcinoma of the prostate. 相似文献
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Michael R. Johns Deidre M. Stuart 《Journal of industrial microbiology & biotechnology》1991,8(1):23-28
Summary The effect of physical and nutritional factors on the production of pigments byMonascus purpureus FRR 2190 was studied using cultures grown on both rice and a synthetic medium that was solidified with carrageenan and extruded into rice-like particles. Pigment yield was highly sensitive to physical parameters. Optimal pigment formation in rice cultures occurred at an initial pH of 6 and an initial moisture content of 56%. Lower moisture contents led to a large decrease in pigment concentration. Red and yellow pigment production on solidified gel media was increased up to three-fold compared to that of liquid cultures of the same medium composition, particularly when peptone was used as the sole nitrogen source. Solid state rice cultures gave the highest pigment yields. 相似文献
134.
G J Kang D A Cooney J D Moyer J A Kelley H Y Kim V E Marquez D G Johns 《The Journal of biological chemistry》1989,264(2):713-718
Cyclopentenylcytosine (CPEC) is phosphorylated in L1210 cells with CPEC triphosphate as the major metabolite. Partially purified uridine-cytidine kinase catalyzes the initial phosphorylation of cyclopentenylcytosine with an apparent Km of 196 +/- 9 microM, and cyclopentenylcytosine is a competitive inhibitor of cytidine phosphorylation by this enzyme with a Ki value of 144 +/- 14 microM. Examination of the CTP synthetase activity in extracts of L1210 cells revealed a dose-dependent decrease on exposure of cells to CPEC. Synthesis of CPEC triphosphate by an enzymatic method permitted direct examination of the inhibition of partially purified CTP synthetase. CPEC triphosphate inhibited bovine CTP synthetase with a median inhibitory concentration of 6 microM, whereas CPEC mono- and diphosphates were ineffective. CTP synthetase showed a classical Michaelis-Menten hyperbolic plot of velocity and UTP concentration in the presence of saturating concentrations of ATP and glutamine, but CPEC triphosphate induced sigmoidal kinetic plots. The Hill coefficient was calculated to be 3.2. 相似文献
135.
Plants used for food by the Luo-speaking people of Siaya District, Kenya, were surveyed as part of a comprehensive ethnobotanical study. Fifty-two crops were observed under cultivation in the district; 69 species are gathered from the wild. Wild fruits, underground portions, leaves, and fungal fruiting bodies are probably important in Siaya as dietary supplements. These non-cultivated resources, particularly important in the driest areas of the district, warrant evaluation for their role as a buffer against periods of food shortage. 相似文献
136.
Laki-laki (Dennstaedtia glauca,polypodiaceae): A green manure used in traditional andean agriculture
Dennstaedia glauca is used as a green manure in specific agricultural contexts in Puno, Perü. It is applied in conjunction with animal manure and prior to potato cultivation in the first year after a period of fallow. Fronds ofD. glauca, while containing average or low amounts of micronutrients, are high in nitrogen, phosphorus, and potassium in comparison with other fern species and plant material in general. We suggest this fern contributes to fertility of soil used for tuber crops. The plant grows in abundance along watercourses and may play an important role as a recycler of nutrients leached from terraced fields. 相似文献
137.
The effect of graded renal nerve stimulation on renal function in the anaesthetized rabbit 总被引:2,自引:0,他引:2
I F Hesse E J Johns 《Comparative biochemistry and physiology. A, Comparative physiology》1984,79(3):409-414
The renal nerves of the rabbit were stimulated to cause less than 5, 9 or 22% reduction in renal blood flow. Glomerular filtration rate was reduced by 0, 3 and 11% respectively when the renal nerves were stimulated at these increasing rates. At low and moderate rates of renal nerve stimulation absolute and fractional sodium excretions were reduced by between 17 and 22%, but at the highest rates they were reduced by 55 and 53% respectively. At increasing rates of renal nerve stimulation plasma renin activity was increased by 40, 70 and 180%. 相似文献
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139.
Improved molecular weight analysis of streptococcal hyaluronic acid by size exclusion chromatography
Summary Four size exclusion chromatography (SEC) calibration techniques were tested for use in the molecular weight characterisation of Streptococcal Hyaluronic Acid (HA). An exponential equation, evaluated using the Hamielec method, was superior to the customary peak position method. It provided the most accurate estimates of the weight average molecular weight, Mw. The calibration was valid for HA in the range 800 – 2500 kDa, and permitted the calculation of both polydispersity and molecular weight distributions for HA from Streptococcal fermentations. This exponential calibration approach should have application in the characterisation of other large biopolymers, particularly where pore size of available SEC media is limiting. 相似文献
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