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91.
Two glycoproteins, GP-1 and GP-2, have been isolated from an extracellular membrane synthesized in cell culture by an embryonal carcinoma-derived cell line. The amino acid and carbohydrate compositions have been determined. Both proteins are rich in half-cystine residues and contain approximately 12-15% carbohydrate. Antibodies have been obtained against one of the glycoproteins, GP-2, in rabbits. The antibody reacts with basement membranes from adult mouse and human kidney glomeruli and tubules, and all basement membranes tested from mouse embryonic tissues. The molecular properties of GP-2 are superficially similar to LETS protein; however, immunological and other criteria show that they are distinct proteins. The presence of LETS protein and GP-2 in basement membranes suggests that there are subtle interactions which are important in adhesion of epithelial cells to basement membranes.  相似文献   
92.
Solutions of native Type III collagen (chain composition, [α1(III)]3) exhibit a rapid and dramatic decrease in relative viscosity when incubated with trypsin. Cleavage products of the reaction were precipitated with ammonium sulfate and isolated in denatured form by molecular sieve chromatography. They were found to be comprised of: α1(III)-T1 (molecular weight, 71,000) derived from the NH2-terminal portion of the Type III molecule; and α1(III)-T2 (molecular weight, 24,000) from the COOH-terminal portion of the molecule. Determination of the amino acid sequence at the NH2-terminal portion of α1(III)-T2 as well as at the COOH-terminus of α(III)-T1 demonstrated that the products arose from specific cleavage of the type III molecule at an arginine-glycine bond corresponding to residues 780–781 in the repetitive triplet sequence of the α1(III) chain. The results suggest that the trypsin-susceptible bond in the native Type III collagen molecule resides in a region characterized by a relative lack of the normal collagen helicity.  相似文献   
93.
In January and February 1974, 32 adults (20 males and 12 females) and a 13-year-old girl with taeniasis saginata were treated with the mixture of boiled areca nuts and pumpkin seeds at Mastoban, Jen-ai District, Nantou County, Taiwan. A total of 48 worms including 42 scolices were recovered from 29 cases. Side-effects were observed in 4 cases including 3 with complaints of dizziness, tinnitus, nausea and vomiting, and one with coma and abdominal pain. Mixtures of 75-150 g areca nuts and 50-100 g pumpkin seeds were judged effective and safe.  相似文献   
94.
An attempt has been made to discriminate additional types of synapses than have been previously described in the nucleus accumbens septi of the cat, which can, according to Brockhaus (1942), justifiably be termed the fundus striati due to the fact that it possesses all of the morphological and some of the neurochemical features of the striatum. This was undertaken in order to correlate at least one type of synapse with each different afferent pathway. Nine distinct types of synapses could be differentiated electron microscopically: Type I: axo-spinous synapses with sparse, small, round vesicles which seemed to be the nigro-striatal endings (35%). Type II: axo-somatic or axo-dendritic en passant synapses containing small, round vesicles (3%). Type III: axo-spinous synapses filled with densely-packed, small, round vesicles displaying strong postsynaptic thickenings which seem to be cortico-striatal (17%). Type IV: large axo-spinous synapses with densely-arranged, small, round vesicles contacting larger spines branching off a pedicle (9%). Type V: axo-somatic or axo-dendritic synapses containing large pleomorphic vesicles, probably axon collaterals (1%). Type VI: axo-somatic or axo-dendritic synapses with elongated small vesicles (20 X 45 nm) (3%). Type VII: large axo-somatic or axo-dendritic synapses filled by densely-packed, small, round vesicles (11%). Type VIII: large axo-somatic or axo-dendritic synapses containing loosely-arranged, small, round vesicles (8%). Type IX: axo-somatic or axo-dendritic synapses containing large, round vesicles in a translucent axoplasm (13%).  相似文献   
95.
1. Gene ? is a recessive lethal factor found in the white strain of axolotls. Animals heterozygous for the gene are phenotypically normal. When mated with each other they give offspring 25% of which exhibit the lethal effects of the gene. 2. The ?/? homozygotes develop normally to an advanced embryonic stage (Harrison stage 40) before the effects of the gene are first manifested. They then come to display a characteristic combination of abnormalities, including a disproportionately small head, small and poorly developed eyes, abnormal poorly developed gills, undifferentiated limb buds, and reduced overall growth rate. They may feed briefly, but soon stop and invariably die within a few weeks of the time of hatching. 3. The action of gene ? has been analyzed by parabiosing mutant and normal embryos, and by grafting various organ primordia reciprocally between mutant and normal embryos. Parabiosis to normal embryos fails to correct the abnormalities of the mutants, although their survival may be somewhat prolonged. Grafts of mutant organ primordia (eye, limb, gill, pronephros, gonad, head) also invariably fail to show improved development or to survive on normal hosts; normal organ primordia develop normally on mutant hosts so long as the mutant survives. These experiments indicate that gene ? is a recessive autonomous cell lethal affecting all of the organ systems during late embryonic and early larval development.  相似文献   
96.
97.
[Purpose] This study aimed to investigate changes in physical activity and energy intake according to abdominal obesity in Korean adult men before and after COVID-19.[Methods] Using data from the 2019 and 2020 KNHANES, the physical activity level measured by the Global Physical Activity Questionnaire (GPAQ) the physical activity level by GPAQ, number of days of walking and strength training, aerobic exercise, and total energy, protein, fat, carbohydrate, dietary fiber, and sugar intake for a total of 2,799 participants were analyzed.[Results] There were no changes in energy intake during the pandemic. The number of days of weekly walking was higher (2019, p = 0.006; 2020, p = 0.012) and strength training was significantly higher (2019, p < 0.0001; 2020 p < 0.0001) in the non-abdominal obesity group than in the abdominal obesity group before and after COVID-19. Strength training at least once a week suppressed abdominal obesity (0.628 times in 2019, p < 0.0001; 0.605 times in 2020, p < 0.0001). In addition, even when the total energy intake and age were adjusted for, strength training influenced the suppression of abdominal obesity (0.634 times in 2019, p < 0.0001; 0.614 times in 2020, p < 0.0001).[Conclusion] Even with the change in the physical activity level, such as walking and aerobic exercise, due to the influence of social distancing measures, strength training influenced the suppression of abdominal obesity, regardless of the COVID-19 pandemic.  相似文献   
98.
K W Chung 《Life sciences》1987,41(17):2077-2082
Specific binding of testosterone-1 beta, 2 beta-3H by cytosol from anterior pituitary gland of alcohol-fed, isocaloric control, and castrated control and alcohol-fed rats with or without testosterone treatment has been investigated by charcoal assay. The number of androgen binding sites was significantly reduced in alcohol-fed rats (8 +/- 1.0 fmoles/mg cytosol protein), when compared to the isocaloric control value (13.2 +/- 2.1 fmoles/mg protein), with no significant change in Kd (0.7 +/- 0.14 nM). Castration significantly increased the number of receptor sites in control rats and when castrated control animals were treated with testosterone the binding sites were decreased to the intact control level. In contrast, castration or testosterone given to castrated alcohol-fed rats did not alter alcohol-induced reduction of the receptor sites. The binding affinity (Kd) is identical in all groups. The concentration of serum luteinizing hormone (LH) was significantly lower in alcohol-fed rats when compared to that of normal controls. An increased serum LH level with a decreased testosterone level was noted in castrated control rats. However, castration of alcohol-fed rats had little or no effects on the concentrations of LH and testosterone. Administration of testosterone suppressed castration-induced high LH in control rats but alcohol-induced reduction of LH level was not altered by this treatment. These findings indicate that alcohol exerts a suppressive effect on the content of androgen receptors and secretory functions of gonadotropins in the pituitary gland.  相似文献   
99.
Cryptorchid testes of testicular feminization rats are very low in zinc in spite of normal zinc status of the animals. Analysis of the cytosol of the cryptorchid testes by gel permeation chromatography showed decreased zinc binding by proteins eluted at fractions corresponding to 30,000 dalton. Further analysis by sodium dodecylsulphate polyacrylamide gel electrophoresis indicated the absence of a protein with molecular weight of 23,000.  相似文献   
100.
In Escherichia coli, the phosphorylation and dephosphorylation of isocitrate dehydrogenase (IDH) are catalyzed by a bifunctional protein kinase/phosphatase. We have determined the nucleotide sequence of aceK, the gene encoding IDH kinase/phosphatase. This gene consists of a single open reading frame of 1,734 base pairs preceded by a Shine-Dalgarno ribosome-binding site. Examination of the deduced amino acid sequence of IDH kinase/phosphatase revealed sequences which are similar to the consensus sequence for ATP-binding sites. This protein did not, however, exhibit the extensive sequence homologies which are typical of other protein kinases. Multiple copies of the REP family of repetitive extragenic elements were found within the intergenic region between aceA (encoding isocitrate lyase) and aceK. These elements have the potential for combining to form an exceptionally stable stem-loop structure (delta G = -54 kcal/mol [ca. -226 kJ/mol]) in the mRNA. This structure, which masks the ribosome-binding site and start codon for aceK, may contribute to the downshift in expression observed between aceA and aceK. Another potential stem-loop structure (delta G = -29 kcal/mol [ca. 121 kJ/mol]), unrelated to the REP sequences, was found within aceK.  相似文献   
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