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71.
Summary A basic procedure was developed to produce a tempe-like product using the mouldRhizopus
oligosporus and black common beans (Phaseolus
vulgaris) as substrate. The initial pH of the substrate was 5.8, and fermentation was conducted at 37°C with a relative humidity of 70% for 72 hrs. Levels of soluble solids and soluble protein increased dramatically as a result of fermentation. Some changes were as well observed in fatty acid contents of fermented samples. It was concluded that the common bean used was an acceptable substrate for preparing this product. 相似文献
72.
Summary
Kluyveromyces fragilis produces polygalacturonase (PG) on a lactose medium. Although the enzyme is normally repressed at high aeration levels, significant amounts of PG can be produced under such conditions when pectin is added as inducer. The productivity and yield of cell mass were not significantly affected by the presence of inducer, suggesting potential applications to current single cell protein processes from whey. 相似文献
73.
The membrane ionic conductances of dispersed parathyroid cells kept in primary culture were studied using the "whole-cell" and "inside-out excised patch" variants of the patch-clamp technique. The major component of the total current was a voltage-dependent outward K+ current without an appreciable inward current. The amplitude of the K+ current was markedly reduced when free internal Ca2+ was buffered by addition of 10 mM EGTA. Recordings of single-channel current in excised membrane patches revealed the presence of K+ channels with large unitary conductance (200 pS in symmetrical 130 mM K+ solutions) which were also activated by depolarization when internal Ca2+ concentration was about 10(-5)-10(-6) M. At any membrane voltage these channels were closed most of the time at internal Ca2+ concentrations lower than 10(-10) M. These results demonstrate the existence of a Ca2+- and voltage-dependent K+ permeability in parathyroid cells which may participate in the unusual membrane potential changes induced by alterations of external Ca2+ and, possibly, in the regulation of parathormone secretion. 相似文献
74.
Serum catalase enzyme activity in liver diseases 总被引:1,自引:0,他引:1
Serum catalase activity was moderately increased in fatty liver, acute alcoholic hepatitis and in the decompensated form of cardiac circulatory failure. It showed significant increase in acute yellow atrophy and in toxic hepatitis while no changes were detected in liver cirrhosis and viral hepatitis. Serum catalase activity showed a good correlation (r = 0.820) with the serum glutamate dehydrogenase activity. In accordance with our results, the inexpensive assay of serum catalase activity is suggested for the detection of severe liver cell damage. 相似文献
75.
Calcium in hippocampus following lidocaine induced seizures: an electron cytochemical study 总被引:1,自引:0,他引:1
The effect of lidocaine seizures on cellular accumulation of calcium was studied in hippocampal subfields CA1 and CA3 and the dentate gyrus of rats, using the combined oxalate-pyroantimonate method. The specificity of the reaction was ascertained by EGTA treatment and X-ray microanalysis. In control rats, calcium was visualized between myelin lamellae of axons, in synaptic vesicles and in some lysosomes. Two hours after onset of lidocaine seizures selective neuronal degenerations appeared in hippocampal subfields CA1 and CA3 but not in the dentate gyrus. Calcium deposits were present in numerous mitochondria of pyramidal cells and, occasionally, also of neuroglial cells. Many of these mitochondria exhibited ultrastructural alterations. Calcium uptake was most prominent in the CA3 sector but was also present in the CA1 subfield as well as the dentate gyrus. Intracellular calcium uptake, in consequence, is not the unique attribute of selectively vulnerable hippocampal neurons. 相似文献
76.
T Skórski M Kawalec J Kawiak 《Folia histochemica et cytobiologica / Polish Academy of Sciences, Polish Histochemical and Cytochemical Society》1987,25(1):23-27
The composition of peritoneal exudate and spleen cells of CD2F1 mice after fourfold i.p. administration of L 1210 leukemia cells treated with cyclophosphamide (L 1210-CY cells) were examined. The number of cells in peritoneal cavity did not increase, however, the spleen weight rose after administration of L 1210-CY cells. The per cent of lymphocytes T was increased 2.5 times but the content of macrophages and lymphocytes B was normal in the peritoneal cavity after L 1210-CY cells injections. In the spleen an 1.4 times increase of the per cent of lymphocytes B, but normal level of macrophages and lymphocytes T were observed. 相似文献
77.
Changes in the serum cortisol level of maternal venous, umbilical venous and umbilical arterial blood were studied separately between the 28th-36th weeks in cases of preterm deliveries (n = 74) and in the 40th week in cases of term delivery (n = 34). Results indicate that between the 28th-40th weeks of pregnancy the cortisol concentration increased only in the serum of the umbilical artery; the "umbilical arterial/umbilical venous concentration X100" quotient rose from a value of 86% measured at 28th-32nd weeks to 103% in the 40th week of pregnancy. Positive correlation was found between the cortisol concentration of the three samples. On the basis of these results the authors believe that fetal adreno-cortical activity increases before birth. 相似文献
78.
Between 1981–83 the gut contents ofDaphnia galeata, D. cucullata, Eudiaptomus gracilis, andCyclops vicinus were examined with light and scanning electron microscope to obtain information on the feeding of these species in Lake Balaton.
The twoDaphnia species feed mainly on abioseston, and it is assumed that their primary nutrient source was organic matter adsorbed onto
the surfaces of the abioseston granules plus bacteria and detritus.E. gracilis feeds on algae, showing a preference for green algae and diatoms.C. vicinus is also a prodigious consumer of algae in Lake Balaton, utilizing the whole size spectrum of phytoplankton.
Concerning the trophic relationships between phytoplankton and zooplankton in Lake Balaton, that between diatoms and bothE. gracilis andC. vicinus is the most conspicouos. Convincing evidence for an extensive utilization of blue-green algae was not found. Though there
is no firm evidence yet, it is likely that theDaphnia are dependent on organic matter adsorbed on the abioseston. 相似文献
79.
Weekly sampling and simultaneous measurements of temperature, pH, and conductivity were made at three stations in the reedbelt,
between 1980–82. 20 cladoceran and 14 copepod species were encountered, of whichCyclops vicinus vicinus was found in the lake for the first time. Of the measured environmental features, temperature showed the greatest seasonal
changes; pH and conductivity were less variable. There were, both quantitatively and qualitatively, constant differences between
the three stations, although they lay close to each other. 相似文献
80.
The role of lipid transfer proteins during plasma membrane biogenesis was explored. Developing amphibia embryos were used because during their growth an active plasma membrane biosynthesis occurs together with negligible mitochondrial and endoplasmic reticulum proliferation. Sonicated vesicles, containing 14C-labeled phospholipids and 3H-labeled triolein, as donor particles and cross-linked erythrocyte ghosts as acceptor particles were used to measure phospholipid transfer activities in unfertilized oocytes and in developing embryos of the toad Bufo arenarum. Phosphatidylcholine transfer activity in pH 5.1 supernatant of unfertilized oocytes was 8-fold higher than the activity found in female toad liver supernatant, but dropped steadily after fertilization. After 20 hr of development, at the stage of late blastula, the phosphatidylcholine transfer activity had dropped 4-fold. Unfertilized oocyte supernatant exhibited phosphatidylinositol and phosphatidylethanolamine transfer activity also, but at the late blastula stage the former had dropped 18-fold and the latter was no longer detectable under our assay conditions. Our results show that fertilization does not trigger a phospholipid transport process catalyzed by lipid transfer proteins. Moreover, they imply that 75% of the phosphatidylcholine transfer activity and more than 95% of the phosphatidylinositol and phosphatidylethanolamine transfer activities present in pH 5.1 supernatants of unfertilized oocytes may not be essential for toad embryo development. Our findings do not rule out, however, that a phosphatidylcholine-specific lipid transfer protein could be required for embryo early growth. 相似文献