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During a period of one year all of 105,724 blood donations were tested for Australia (Au) antigen and its antibody by rapid immunoelectro-osmophoresis—86 (1 in 1,229) were positive for antigen and 67 (1 in 1,578) positive for antibody. Second donations by previously negative donors reduce the overall incidence of positives. Men prisoners have a significantly higher incidence of Au antigen (1 in 153) than non-institutionalized men (1 in 803). The latter have a significantly higher incidence of antigen than women (1 in 2,019). Only one antigen-positive donor was incubating acute viral hepatitis. Failure to detect one strong and one weak antigen was responsible for two cases of posttransfusion Au-antigen-positive hepatitis. 相似文献
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Carbon-halogen bond cleavage. 3. Studies on bacterial halidohrolases 总被引:21,自引:0,他引:21
157.
A F Milne J N Williams F B Rudolph 《Comparative biochemistry and physiology. B, Comparative biochemistry》1978,59(3):199-200
The specific activity of the lysosomal enzyme N-acetyl-beta-D-hexosaminidase was determined in the caput and cauda of the epididymis of rats as a function of age. The activity peaks at six weeks of age in both parts of the epididymis but is higher in the cauda. The results indicate a relationship between changes occurring in sperm in the epididymis and the lysosomal enzymes. 相似文献
158.
Bidhan Bhuson Roy Rubel Biswas Chowdhury Amit Robert Baroi Shupa Rahman Stephen M. Powers Nick Milne Mohammad Sujauddin 《Journal of Industrial Ecology》2019,23(6):1439-1455
Phosphorus (P) is central to food production. Current understanding about the global phosphorus system is dominated by studies in wealthier nations where soil fertility, fertilizer supply chains, and agronomic tracking have long been established. In contrast, developing nations are experiencing major agricultural transitions and the associated phosphorus flows remain a significant knowledge gap. We compiled and analyzed several years of recent agricultural datasets for Bangladesh, currently the eighth most populous nation, using substance flow analysis for phosphorus. From 2000 to 2016, rice production increased by >50% and remained the dominant crop with remarkably higher phosphorus flow (49.96 kt in 2016) than all other crops. Phosphorus content of livestock products in 2016 exceeded 6.00 kt, more than double in the year 2000, driven primarily by phosphorus in milk and secondarily in meat/eggs. These agricultural changes coincided with a doubling of national phosphorus fertilizer consumption since 2000, a fourfold increase since the global food crisis (2009), and a pronounced rise in the phosphorus import dependency ratio, which was the highest among all countries compared. In turn, during 2010s fertilizer phosphorus use exceeded phosphorus as food + feed production leading to soil phosphorus accumulation, and loss as burned manure became one of the largest phosphorus flows in the entire system, equivalent to half of fertilizer use. This dramatic reconfiguration of the Bangladesh phosphorus system illustrates an important case of agricultural expansion and intensification that is still playing out, with similar situations occurring in developing nations where population growth rates are high, and access to commercial fertilizers has risen. 相似文献
159.
Zopiclone is a poorly soluble psychotherapeutic agent. The aim of this study was to prepare and characterize an amorphous form of zopiclone as well as the characterization and performance of a stable amorphous solid dispersion. The amorphous form was prepared by the well-known method of quench-cooling of the melt. The solid dispersion was prepared by a solvent evaporation method of zopiclone, polyvinylpyrrolidone-25 (PVP-25), and methanol, followed by freeze-drying. The physico-chemical properties and stability of amorphous zopiclone and the solid dispersion was studied using differential scanning calorimetry (DSC), infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), hot-stage microscopy (HSM), X-ray diffractometry (XRD), solubility, and dissolution studies. The zopiclone amorphous solid-state form was determined to be a fragile glass; it was concluded that the stability of the amorphous form is influenced by both temperature and water. Exposure of amorphous zopiclone to moisture results in rapid transformation of the amorphous form to the crystalline dihydrated form. In comparison, the amorphous solid dispersion proved to be more stable with increased aqueous solubility.KEY WORDS: amorphous, fragile, solid dispersion, stability, zopiclone 相似文献
160.
In the overnourished adolescent sheep, maternal tissue synthesis is promoted at the expense of placental growth and leads to a major decrease in lamb birth weight at term. Maternal growth hormone (GH) concentrations are attenuated in these pregnancies, and it was recently demonstrated that exogenous GH administration throughout the period of placental proliferation stimulates uteroplacental and fetal development by Day 81 of gestation. The present study aimed to determine whether these effects persist to term and to establish whether GH affects fetal growth and body composition by increasing placental size or by altering maternal metabolism. Adolescent recipient ewes were implanted with singleton embryos on Day 4 postestrus. Three groups of ewes offered a high dietary intake were injected twice daily with recombinant bovine GH from Days 35 to 65 of gestation (high intake plus early GH) or from Days 95 to 125 of gestation (high intake plus late GH) or remained untreated (high intake only). A fourth moderate-intake group acted as optimally nourished controls. Pregnancies were terminated at Day 130 of gestation (6 per group) or were allowed to progress to term (8-10 per group). GH administration elevated maternal plasma concentrations of GH, insulin, glucose, and nonesterified fatty acids during the defined treatment windows, while urea concentrations were decreased. At Day 130, GH treatment had reduced the maternal adiposity score, percentage of fat in the carcass, and internal fat depots and leptin concentrations, predominantly in the high-intake plus late GH group. Placental weight was lower in high-intake vs. control dams but independent of GH treatment. In contrast, fetal weight was elevated by late GH treatment, and these fetuses had higher relative carcass fat content, perirenal fat mass, and liver glycogen concentrations than all other groups. Expression of leptin mRNA in fetal perirenal fat and fetal plasma leptin concentrations were not significantly altered by maternal nutritional intake or GH. In pregnancies proceeding to term, the duration of gestation, fetal placental mass, and lamb birth weight were reduced in high-intake compared with control dams but were not significantly affected by GH treatment. In conclusion, exogenous GH has profound effects on maternal endocrinology, metabolism, and body composition when administered during early and late pregnancy. Treatment during late pregnancy has a modest effect on fetal growth independent of placental size and a profound effect on fetal adiposity, which may have implications beyond the fetal period. 相似文献