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691.
H.H. Yeoh  M.Y. Chew 《Phytochemistry》1976,15(11):1597-1599
On the basis of leaf dry wt, the protein content of six varieties of cassava varied from 29.3 to 38.6% and the estimated leaf protein production ranged from 242 to 953 kg per ha. On the basis of fr. wt of leaf, the total amino acids ranged from 8.42 to 9.4% while the essential amino acids averaged 4.21% and the sulphur-containing amino acids only 0.25%. The amino acid composition profiles for the six varieties was similar.  相似文献   
692.
1. Glutamate dehydrogenase, aspartate transaminase and alanine transaminase were present in the gill, liver and muscle tissues of Periophthalmodon schlosseri and Boleophthalmus boddaerti. Both transaminases were found in the cytosol and mitochondria. 2. A complete purine nucleotide cycle was not present in the tissues studied. 3. Glutamine synthetase was not detected. Phosphate-dependent glutaminase was detected in both the cytosol and mitochondria. 4. Aspartate was the major substrate of ammoniagenesis in the mudskippers, though glutamate and glutamine were also oxidised. 5. Transdeamination was the major pathway for ammoniagenesis in the mudskippers studied.  相似文献   
693.
Simulated stream conditions were used to expose underyearling Pacific salmon (genus Oncorhynchus) to sublethal doses of TCMTB (2-thiocyanomethylthio) benzothiazole; a fungicide used by the lumber industry to protect against discolouration by sapstain fungi. Observed changes in schooling, swimming, and respiration were studied in more detail utilizing progressively more complex and ecologically relevant experimental designs. Laboratory troughs (600 litre) were used to quantify innate shelter-seeking behaviour and susceptibility to predation during salinity stress. Swimming speed, schooling behaviour and responses to salinity and hypoxia were studied in a 4500-litre Water Column Simulator under vertically stratified conditions (fresh water overlying sea water). Finally a similarly stratified 15,500-litre outdoor tank was designed to compare susceptibility to predation during a volitional salinity challenge. Relative to controls, TCMTB-exposed underyearling salmon exhibited a reduction in cover response, were slower to seek shelter from bright light, were more erratic in their swimming behaviour and more likely to be eaten by marine predators. Videotape analyses confirmed that TCMTB reduced exploratory behaviour and swimming speed under both normoxic and hypoxic conditions in the WCS. The ecological consequences of these overt behavioural changes were experimentally linked to a clear increase in risk from predation by yellowtail rockfish (Sebastes flavidus) inhabiting the marine zone below the halocline of the 15,500-litre tank. These techniques illustrate our most recent efforts to correlate cumulative sublethal physiological stress with ecologically meaningful behavioural dysfunction.  相似文献   
694.
Second-order rate constants (k2) are reported for the reduction of 9-R-10-methylacridinium cations (5:R = H, CH3, CH3CH2, C6H5CH2, (CH3)2CH, C6H5, 4-(CH3)2NC6H4) by 1-benzyl-1,4-dihydronicotinamide (2:R = C6H5CH2) in 20% CH3CN-80% H2O at 25°C. All 5:R ≠ H are reduced in the range 20- to 140-fold more slowly than 5:R = H. However, there is no simple relationship between k2 and the nature of R, nor between k2 and the second-order rate constant for hydroxide ion attack at C-9 of these cations in pseudobase formation. Rates of reduction of 5 by 1-benzyl-4,4-dideuterio-1,4-dihydronicotinamide allow the calculation of the following kinetic isotope effects in this solvent medium: 5:R, kHkD:H, 1.56; C6H5CH2, 2.7; C6H5, 5.4. Substituent effects upon k2 were evaluated for the reduction of 5 by 1-(X-benzyl)-1,4-dihydronicotinamides, and lead to the following Hammett ? parameters: 5:R, ?: H, ?0.68; C6H5CH2, ?0.92; C6H5, ?0.96. The latter two values require essentially complete unit positive charge generation on the nicotinamide moiety in the rate-determining transition state. It is shown that these Hammett ? values and the above isotope effects can only be rationalized by a two-step e? + H? mechanism for hydride transfer from 2 to 5 in this solvent system. This result contrasts with our earlier conclusion of direct, one-step hydride transfer in the reduction of isoquinolinium cations by 2, but is consistent with our observation that acridinium cations are reduced 37500-fold faster by 2 than predicted on the basis of the relative rates of nucleophilic attack (hydroxide ion) on acridinium and isoquinolinium cations. It is suggested that the availability of both Hammett ? values and primary kinetic isotope effects will generally allow the establishment of the mechanism of hydride transfer in these systems. Application of these ideas to literature data suggests that 5:R = H is reduced by direct hydride transfer in acetonitrile solution, in contrast to the above result in predominantly aqueous solution. The ready formation of acridanyl radicals by electron transfer to acridinium cations is demonstrated by the formation of Wurster's Blue radical cation upon mixing solutions of acridinium cations with N,N,N′,N′-tetramethyl-p-phenylenediamine.  相似文献   
695.
This paper describes a refinement in the purification step that facilitated the downstream recovery of high purity BmR1 recombinant protein, which is a protein used as a test reagent in the commercialized rapid tests for detection of lymphac filariasis i.e. Brugia RapidTM and panLF rapidTM. Purification was performed by immobilized metal affinity chromatography (IMAC), followed by ion exchange chromatography (IEX). Results showed that a total of 10.27 mg of BmR1 was obtained when IMAC was performed using 20 mM of imidazole and 5 column volume of wash buffer containing 500 mM of NaCl. Purity of the target protein was enhanced when buffer at pH 5.8 was used during the IEX. Two proteins that recurrently appeared below the BmR1 recombinant protein were identified by mass-spectrometry analysis as the same protein, thus they were probably degradation products of BmR1. These strategies improve purity of the target protein to be used in applications such as production of aptamers and monoclonal antibodies.  相似文献   
696.
697.

Background  

Incorporation of exon 11 of the insulin receptor gene is both developmentally and hormonally-regulated. Previously, we have shown the presence of enhancer and silencer elements that modulate the incorporation of the small 36-nucleotide exon. In this study, we investigated the role of inherent splice site strength in the alternative splicing decision and whether recognition of the splice sites is the major determinant of exon incorporation.  相似文献   
698.
ObjectiveType 2 diabetes mellitus and nonalcoholic fatty liver disease (NAFLD) are closely related, and antidiabetic medications have been shown to be potential therapeutics in NAFLD. Using a network meta-analysis, we sought to examine the effectiveness of antidiabetic agents for the treatment of NAFLD in patients with type 2 diabetes mellitus.MethodsMedline and Embase were searched for randomized controlled trials relating to the use of antidiabetic agents, including sodium-glucose transport protein 2 (SGLT2) inhibitors, glucagon-like peptide-1 receptor agonists, and peroxisome proliferator-activated receptor gamma (PPARγ) agonists, biguanides, sulfonylureas and insulin, on NAFLD in patients with diabetes. The p-score was used as a surrogate marker of effectiveness.ResultsA total of 14 articles were included in the analysis. PPARγ agonists were ranked as the best treatment in steatosis reduction, resulting in the greatest reduction of steatosis. There was statistical significance between PPARγ agonists [mean difference (MD): ?6.02%, confidence interval (CI): ?10.37% to ?1.67%] and SGLT2 inhibitors (MD: ?2.60%, CI: ?4.87% to ?0.33%) compared with standard of care for steatosis reduction. Compared with PPARγ agonists, SGLT2 inhibitors resulted in a statistical significant reduction in fibrosis (MD: ?0.06, CI: ?0.10 to ?0.02). Body mass index reduction was highest in SGLT2 inhibitors and glucagon-like peptide-1 receptor agonists. Additionally, SGLT2 inhibitors were ranked as the best treatment for increasing high-density lipoprotein and reducing low-density lipoprotein.ConclusionGlucagon-like peptide-1 receptor agonists and SGLT2 inhibitors were suitable alternatives for the treatment of NAFLD in those with type 2 diabetes mellitus with a reduction in body mass index, fibrosis, and steatosis. SGLT2 inhibitors also have the added benefit of lipid modulation.  相似文献   
699.
The kinetics of Breinlia booliati infection in 3 inbred rat strains (Lewis, Wistar and Sprague Dawley) were investigated. One group of rats was infected as neonates (less than 24 hours of age) with third-stage larvae of B. booliati and the other group was infected as juveniles (4 weeks of age). The results showed that infection in the neonates were significantly different from the infection in the juveniles. The 60 rats infected as neonates, when necropsied between 8 to 10 months postinfection, yielded adult worms. The 2 neonatal infection groups of Lewis and Wistar strains showed highest susceptibility to the infections. The mean prepatent period was 85 days. Ninety to 95% of the infected rats were patent with microfilaraemia and a large percentage (33 to 47%) of them had high microfilaraemia counts exceeding 3000 mff/20 mm3 of blood and larger sizes (mean 157.11 mm for female adult worms and 61.88 mm for male adult worms. The adult worms were distributed equally in both the pleural (57%) and peritoneal cavity (43%). In most aspects, the neonatal infection group of the Sprague-Dawley strain was intermediate in susceptibility between the 2 neonatal infection groups of the Lewis and Wistar strains and the 3 juvenile infection groups. In contrast to neonatal infection groups, the 3 juvenile infection groups exhibited low infection rates (37%, 58% and 47% for the Lewis, Wistar and Sprague Dawley strains respectively), longer prepatent periods (mean 101 days), lower recovery rates (2 to 4%), lower adult worm loads (mean 0.4 to 0.8 female worms, and 0.2 to 0.8 male worms per rat), and smaller sizes (mean 141.24 mm for female adult worms and 53.75 mm for male adult worms). Forty-four to 57% of these infected rats harboured either single male or single female adult worms in the body cavity. Most (92%) of the adult worms recovered from the juvenile infection groups resided in the pleural cavity and the remaining 8% were recovered from the peritoneal cavity. Microfilaraemia could be detected in only 3/20 Lewis rats, 5/20 Wistar rats and 5/20 Sprague Dawley rats. The mean peak microfilaraemia of the 3 pooled juvenile infection groups was 632 mff/20 mm3 of blood, ranging from 7 mff/20 mm3 to 1856 mmf/20 mm3. Our results indicate that the susceptibility to B. booliati infection in white rats is both genetic and age-associated. The responses of the 2 distinct infection groups to B. booliati infections are discussed.  相似文献   
700.
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