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排序方式: 共有624条查询结果,搜索用时 15 毫秒
41.
Search for Related Substances in Market Products Containing Enalapril Maleate as the Active Principle 总被引:4,自引:0,他引:4
C. Pilatti I. Ercolano M. del C. Torre C. Chiale M. Spinetto 《Drug development and industrial pharmacy》1999,25(6):807-811
This study's main object was the determination of substances, by means of high-performance liquid chromatography (HPLC), that are related to enalapril maleate in medicinal tablets. The research was on products containing a 20 mg active principle with a 12-month Δt and on those batches near their expiration date with an enalapril maleate concentration of 10, 5, and 2.5 mg. 相似文献
42.
We report how dodecanethiol (DT) surfactant can be used as a good dispersant to solubilize octadecylamine functionalized single-walled carbon nanotubes (ODA-SWCNTs) in order to confine them in the polystyrene phase of the polystyrene-b-polyisoprene-b-polystyrene (SIS) block copolymer matrix. It has been also demonstrated how the block copolymer matrix is not able to self-assemble in ordered morphology when the ODA-SWCNTs are not modified with the surfactant. DT assisted confinement of carbon nanotubes into the PS phase causes not only the nanostructuration of the host polymer matrix but also switches the self-assembled nanostructure from ordered cylinders in the case of neat SIS to a self-assembled lamellar nanostructure. 相似文献
43.
44.
The need to defluoridate and fluoridate the water supplies in areas with drinking water naturally containing above-optimal (>/=2.5 mg/l) and suboptimal (=0.3 mg/l) fluoride concentration and caries and fluorosis prevalence of 12-year-old schoolchildren were assessed in Italy. In the low-fluoride area, 48.4% children were caries-free (DMFT = 0) and the DMFT and DMFS were 1.5 and 2.6; in the high-fluoride area, 46.8% had a DMFT = 0 and the values of the indices were 1.4 and 1.6, respectively. Multiple logistic regression analysis showed a significant association in the caries-free status according to parents' employment status (OR = 1.2, 95% CI = 1.1-1.3) and children's sweets consumption, since children who consumed sweets at least once a day had an adjusted odds ratio of 1.8 (95% CI = 1.4-2.3) compared to those with a lower consumption. Multiple linear regression analysis showed that DMFT and DMFS were significantly higher in children with a lower socioeconomic status and in those who consumed sweets at least once a day, with the DMFS significantly associated also with the area of residence. DT and FT scores were higher in the high- and low-fluoride areas, respectively. No evidence of fluorosis was reported in 94.5 and 55.3% of children in the low- and high-fluoride areas, respectively. The Community Fluorosis Index (CFI) for all permanent teeth was significantly higher in the high-fluoride area, 0.8, than the value, 0.1, found in the low-fluoride community. Our results substantiate the difficulties in defining universal guidelines for the fluoridation or defluoridation of drinking water and the need for an epidemiological approach to the decision as to fluoridate and defluoridate the water supply. 相似文献
45.
In the present study we analyzed breast milk samples from mothers of breast-fed, healthy, term babies with unexplained prolonged jaundice for beta-glucuronidase activity. The differences of enzyme activity were not statistically significant in comparison to a control group of nonjaundiced newborns. We conclude that beta-glucuronidase is not the only cause of prolonged jaundice in neonates. 相似文献
46.
Free amino acids and volatile compounds were analysed in a Roncal-type cheese made from pasteurized ovine milk with and without an added adjunct culture (Lactobacillus paracasei + Lactobacillus plantarum). In both batches, the total free amino acid concentration increased 11–12-fold with ripening time, the main amino acids being Leu, Glu, Lys, Phe, Val, and Ile. At the end of ripening, significant differences were recorded for Leu, Ile, Gaba, Phe, Pser, Ser, Gin, Ala, and Orn. 相似文献
47.
Microbiological, physicochemical, and sensory characteristics of kefir during storage 总被引:1,自引:0,他引:1
Changes in certain microbiological, physicochemical, and sensory parameters of kefir were studied during refrigerated storage. Kefir batches were prepared using 1% and 5% added kefir grains, and samples for analysis were taken 24 h after inoculation and then after 2, 7, 14, 21, and 28 days of storage at 5 ± 1 °C. After fermentation for 24 h after inoculation, lactobacilli and lactococci were present at levels of 108 cfu/ml, and yeasts and acetic acid bacteria were present at levels of 105 and 106 cfu/ml, respectively. The lactic acid flora decreased by about 1.5 log units between days 7 and 14 and then stabilized at that level. Yeast and acetic acid bacterial counts, lactose, and pH all remained constant over the storage period, while the total fat content and dry matter decreased. The percentage inoculate did exert an influence, and the sample batches made using 1% added kefir grains had higher lactic acid bacterial counts, lactose, and pH, while the sample batches made using 5% added kefir grains had higher yeast and acetic acid bacterial counts and viscosity. The total fat and dry matter contents were similar in both sample batches. Sensory analysis of the kefir samples revealed maximum acceptability levels in the first 2 days of storage. 相似文献
48.
pS2 is a small protein (7000 daltons) that is prevalently expressed in human breast cancer positive for estrogen receptors: protein is, in fact, induced by estrogen stimulation. Studies indicate that pS2 protein is a marker for hormone-dependent breast tumors and that its expression is helpful in the prognosis. The presence of pS2, in fact, besides being associated in 96% of the cases to the positivities for estrogen receptors, is associated with longer overall, and disease free, survival. The pS2 protein is also expressed in normal stomach mucosa; its physiological function is unknown. 相似文献
49.
A direct method for measuring the ratio of the interaction field distribution and the critical field distribution in a wide variety of longitudinal recording media is presented. The method requires only the measurement of mp, the normalized remanence of the sample at the conclusion of the magnetizing process Hsal, -hci , +hci, where Hsat is a field large enough to saturate it and hci is the operative remanence coercivity. In conjunction with major loop measurements, the method obtains both the standard deviation in the interaction field distribution and the standard deviation in the critical field distribution. Experimental verification of the proposed technique is presented 相似文献
50.
There are multiple components to the concept of Umwelt experienced by an organism that may constrain the type and structure of communication signals as well as the usefulness of these signals. To illustrate the impact of these multiple environmental components, the authors used signals of the pygmy marmoset (Cebuella pygmaea), a small primate from the western Amazon. The authors summarize studies to show how the physical effects of the habitat; effects of other species, both predators and nonpredators; anthropogenic effects on the communication environment; within-group and between-groups influences other pygmy marmosets exert; and ontogeny influence the structure and usage of vocal signals. Communication within a species can be understood only in consideration of each of these contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献