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This paper explores familial contexts of transition to a wage labor economy using ethnographic and survey data from Tamang communities at the northern edge of Nepal's Kathmandu Valley. Historically agro-pastoralist, the Tamang of this area have experienced social watersheds drawing them into ever closer relationships with Kathmandu. The earliest was their nineteenth century induction into corvée labor for national elites; more recent has been the accelerating monetization of the twentieth century. This analysis demonstrates trends and frames hypotheses about the social structuring of this latest process, testing them at the individual level with combined ethnographic and survey data from 1028 respondents. Multivariate analyses explore the effects of birth cohort, education, domestic group status, and settlement location on participation in non-family organized wage work. Substantive findings are related to the broader historical literature on household and family with special attention to varieties of subsistence to monetized transition.  相似文献   
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The histological effect on and stress response of post juvenile Clarias gariepinus exposed to Qua Iboe crude oil and rig wash were investigated. Fish weighing 60–90 g and measuring 16–18 cm were exposed for 7–28 days to 8.00 ml?1 Qua Iboe crude oil and 0.0018 ml–1 rig wash, both being 0.1 of the 96 hr LC50. Blood samples of C. gariepinus were collected every seven days and evaluated for stress by measuring cortisol concentration. The gills and liver were studied and scored for Gill Alteration Index (GAI) and Hepatic Alteration Index (HAI), respectively. There was an increase in cortisol level up to the 7th and 14th day among the group exposed to Qua Iboe crude oil, with a decrease on the 21st and 28th day. The rig wash group increased in cortisol level up to the 7th day and decreased slightly on the 14th day, after which the trend became irregular. The toxic effects of the Qua Iboe crude oil and rig wash were time dependent, as shown by the histopathological alteration index (HAI) of gill and liver. After 28 days of exposure, the gills had irreparable damage due to high frequency of cellular necrosis and degeneration, whereas the liver had from moderate to severe damage due to the high frequency of cellular degeneration and inflammation. Qua Iboe crude oil and rig wash are both toxic to C. gariepinus, therefore their indiscriminate discharge to the environment must be discouraged.  相似文献   
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We report a female infant with partial trisomy 8p (8p11.2-->pter) and deletion of 13q (13q32-->qter). She was born with mild hypotonia, intrauterine growth retardation, microcephaly, micrognathia, large low set ears, pectus excavatum, anteriorly placed anus, and bilateral clinodactyly. Echocardiography showed left ventricular hypertrophy, bicuspid aortic valve, dilatation of the aorta and pulmonary artery, and prolapse of atrio-venticular valve leaflets. Cytogenetic investigation of her sister and her father showed that the altered region resulted from a balanced translocation between the part of the long arm of chromosome 13 and short arm of chromosome 8. In partial trisomy 8p, the clinical picture of the patients comprises hypotonia, structural brain abnormalities, facial anomalies including a large mouth with a thin upper lip, a high arched palate, a broad nasal bridge, an abnormal maxilla or mandible, malformed, low set ears, and orthopedic anomalies. Although patients with proximal deletions of 13q that do not extend into band q32 have mild to moderate mental and growth delays with variable minor anomalies, patients with more distal deletions including at least part of band q32 usually have major malformations such as retinoblastoma, mental-motor growth retardation, malformation of brain and heart, anal atresia, and anomalies of the face and limbs. To our knowledge partial trisomy 8p and partial monosomy of 13q have not been reported previously in the same person.  相似文献   
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Myelocytomatosis oncogene (c‐MYC) is a well‐known nuclear oncoprotein having multiple functions in cell proliferation, apoptosis and cellular transformation. Chromosomal modification is also important to the differentiation and growth of stem cells. Histone deacethylase (HDAC) and polycomb group (PcG) family genes are well‐known chromosomal modification genes. The aim of this study was to elucidate the role of c‐MYC in the expression of chromosomal modification via the HDAC family genes in human mesenchymal stem cells (hMSCs). To achieve this goal, c‐MYC expression was modified by gene knockdown and overexpression via lentivirus vector. Using the modified c‐MYC expression, our study was focused on cell proliferation, differentiation and cell cycle. Furthermore, the relationship of c‐MYC with HDAC2 and PcG genes was also examined. The cell proliferation and differentiation were checked and shown to be dramatically decreased in c‐MYC knocked‐down human umbilical cord blood‐derived MSCs, whereas they were increased in c‐MYC overexpressing cells. Similarly, RT‐PCR and Western blotting results revealed that HDAC2 expression was decreased in c‐MYC knocked‐down and increased in c‐MYC overexpressing hMSCs. Database indicates presence of c‐MYC binding motif in HDAC2 promoter region, which was confirmed by chromatin immunoprecipitation assay. The influence of c‐MYC and HDAC2 on PcG expression was confirmed. This might indicate the regulatory role of c‐MYC over HDAC2 and PcG genes. c‐MYCs’ regulatory role over HDAC2 was also confirmed in human adipose tissue‐derived MSCs and bone‐marrow derived MSCs. From this finding, it can be concluded that c‐MYC plays a vital role in cell proliferation and differentiation via chromosomal modification.  相似文献   
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A maltooligosaccharide-forming α-amylase was produced by a new soil isolate Bacillus subtilis KCC103. In contrast to other Bacillus species, the synthesis of α-amylase in KCC103 was not catabolite-repressed. The α-amylase was purified in one step using anion exchange chromatography after concentration of crude enzyme by acetone precipitation. The purified α-amylase had a molecular mass of 53 kDa. It was highly active over a broad pH range from 5 to 7 and stable in a wide pH range between 4 and 9. Though optimum temperature was 65–70 °C, it was rapidly deactivated at 70 °C with a half-life of 7 min and at 50 °C, the half-life was 94 min. The K m and V max for starch hydrolysis were 2.6 mg ml−1 and 909 U mg−1, respectively. Ca2+ did not enhance the activity and stability of the enzyme; however, EDTA (50 mM) abolished 50% of the activity. Hg2+, Ag2+, and p-hydroxymercurybenzoate severely inhibited the activity indicating the role of sulfydryl group in catalysis. The α-amylase displayed endolytic activity and formed maltooligosaccharides on hydrolysis of soluble starch at pH 4 and 7. Small maltooligosaccharides (D2–D4) were formed more predominantly than larger maltooligosaccharides (D5–D7). This maltooligosaccharide forming endo-α-amylase is useful in bread making as an antistaling agent and it can be produced economically using low-cost sugarcane bagasse.  相似文献   
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It has been reported in some cases that an increase in pCO2 stimulates growth in diluted cell suspension cultures. Experiments have been designed to study the pattern of dark CO2 fixation in sycamore cells grown in liquid suspension and to correlate this pattern with the culture growth phases. Comparisons were made between enzymatic activities, CO2 incorporation, malic acid content during lag, logarithmic and stationary phases of growth. Malic enzyme (NADP-dependent) was at its maximum activity during early logarithmic growth phase, when biosynthetic capacities were at the highest. Phosphoenolpyruvate-carboxylase activity was strongly correlated with the ability of cells to fix CO2. Malic acid content decreased soon after transfer of the cells to a new medium and increased at the onset of stationary phase. Under optimal conditions, the CO2 incorporation pattern did not change during growth, with an almost identical incorporation in the basic (amino acids) and acidic (organic acids) fractions. These observations have been discussed in relation to a possible effect of increased pCO2 in the cell environment.  相似文献   
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Extracts of pine needles (Pinus densiflora Sieb. et Zucc.) have diverse physiological and pharmacological actions. In this study we show that pine needle extract alters pacemaker currents in interstitial cells of Cajal (ICC) by modulating ATP-sensitive K+ channels and that this effect is mediated by prostaglandins. In whole cell patches at 30 degrees , ICC generated spontaneous pacemaker potentials in the current clamp mode (I = 0), and inward currents (pacemaker currents) in the voltage clamp mode at a holding potential of -70 mV. Pine needle extract hyperpolarized the membrane potential, and in voltage clamp mode decreased both the frequency and amplitude of the pacemaker currents, and increased the resting currents in the outward direction. It also inhibited the pacemaker currents in a dose-dependent manner. Because the effects of pine needle extract on pacemaker currents were the same as those of pinacidil (an ATP-sensitive K+ channel opener) we tested the effect of glibenclamide (an ATP-sensitive K+ channels blocker) on ICC exposed to pine needle extract. The effects of pine needle extract on pacemaker currents were blocked by glibenclamide. To see whether production of prostaglandins (PGs) is involved in the inhibitory effect of pine needle extract on pacemaker currents, we tested the effects of naproxen, a non-selective cyclooxygenase (COX-1 and COX-2) inhibitor, and AH6809, a prostaglandin EP1 and EP2 receptor antagonist. Naproxen and AH6809 blocked the inhibitory effects of pine needle extract on ICC. These results indicate that pine needle extract inhibits the pacemaker currents of ICC by activating ATP-sensitive K+ channels via the production of PGs.  相似文献   
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