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771.
Four diterpenes were isolated from the stem bark of Xylopia acutiflora and characterized as (?)-kauran-16α-ol, 7,8-acetoxy-(?)-kaur-16-en-19-oic acid, 15-oxo-(?)-kaur-16-en-19-oic acid, and 16α- hydroxy-(?)-kauran-19-oic acid. 相似文献
772.
Roseanne M. Lorenzana Aaron Y. Yeow Joan T. Colman Lara L. Chappell Harlal Choudhury 《人类与生态风险评估》2009,15(1):185-200
Major sources of arsenic exposure for humans are foods, particularly aquatic organisms, which are called seafood in this report. Although seafood contains a variety of arsenicals, including inorganic arsenic, which is toxic and carcinogenic, and arsenobetaine, which is considered nontoxic, the arsenic content of seafood commonly is reported only as total arsenic. A goal of this literature survey is to determine if generalizable values can be derived for the percentage of total arsenic in seafood that is inorganic arsenic. Generalizable values for percent inorganic arsenic are needed for use as default values in U.S. human health risk assessments of seafood from arsenic-contaminated sites. Data from the worldwide literature indicate the percent of inorganic arsenic in marine/estuarine finfish does not exceed 7.3% and in shellfish can reach 25% in organisms from presumably uncontaminated areas, with few data available for freshwater organisms. However, percentages can be much higher in organisms from contaminated areas and in seaweed. U.S. site-specific data for marine/estuarine finfish and shellfish are similar to the worldwide data, and for freshwater finfish indicate that the average percent inorganic arsenic is generally < 10%, but ranges up to nearly 30%. Derivation of nationwide defaults for percent inorganic arsenic in fish, shellfish, and seaweed collected from arsenic-contaminated areas in the United States is not supported by the surveyed literature. 相似文献
773.
Rogelio
Rosas‐Valdez Anindo Choudhury Gerardo
Pérez‐Ponce
De
León 《Zoologica scripta》2011,40(3):296-305
Rosas‐Valdez, R., Choudhury, A. & Pérez‐Ponce de León, G. (2011). Molecular prospecting for cryptic species in Phyllodistomum lacustri (Platyhelminthes, Gorgoderidae). —Zoologica Scripta, 40, 296–305. Partial sequences of the 28S ribosomal RNA and cytochrome c oxidase I (COI) genes were compared among populations of a widely distributed and morphologically uniform digenean species in North America, Phyllodistomum lacustri, a parasite characteristically associated with ictalurid catfishes. Specimens were collected from the urinary bladder of ictalurid hosts in six localities of North America, spanning most of the latitudinal range of this freshwater fish group. Sequences of other congeneric species, including a potentially close relative, P. staffordi, were also obtained and used for comparison. Analyses of both molecular markers show very low or no intrapopulation variation within each sampling site. However, samples of P. lacustri from different hosts and regions exhibit varying levels of interpopulation genetic differences. Such differences are explained by the wide geographical distribution and host range of the ictalurids they parasitize, particularly in ictalurids distributed in Mexican freshwaters where they experienced a diversification process. Variation in both nuclear and mitochondrial genes and phylogenetic analyses, in conjunction with geographical and host information (drainage isolation and endemicity of the host species), indicate that at least three populations show potential as cryptic species. 相似文献
774.
A new steroidal alkaloid has been isolated from the leaves of Buxus papilosa. Its structure has been assigned as 1 on the basis of spectroscopic studies. 相似文献
775.
776.
Senescence of Detached Fern Leaves 总被引:1,自引:0,他引:1
Biswal Basanti; N. K. Choudhury; Sahu Prativa; U. C. Biswal 《Plant & cell physiology》1983,24(7):1203-1208
Detached fern leaves show a loss in the content of pigments,protein and a decline in 2,6-dichlorophenol indophenol Hillreaction of isolated chloroplasts during aging. Light treatmentof leaves could considerably retard aging induced loss in 2,6-dichlorophenolindophenol photoreduction but it exhibits less effect on pigmentand protein loss. (Received February 7, 1983; Accepted July 14, 1983) 相似文献
777.
Li’na Zhao Pinghua Zhang Qianqian Zheng Anupam Deka Rupshikha Choudhury Sanjay Rastogi 《Endocrine practice》2022,28(2):135-141
ObjectiveThe present study aimed to evaluate gestational diabetes mellitus (GDM) incidence in pregnant women following the Mediterranean diet (MedDiet) with the addition of extra virgin olive oil (EVOO) and pistachios.MethodsA total of 560 pregnant patients were enrolled in the present study. The MedDiet was introduced in both the interventional group (IG) and the control group. The women in the IG received 40 mL of EVOO every day along with 25 to 30 g of roasted pistachios. The incidence of GDM was recorded along with specific maternal and neonatal outcomes.ResultsThe nutritional scores and MedDiet adherence screener scores were not statistically different between the groups at baseline, but the difference was statistically significant and higher in the IG at 24 to 28 weeks (P = .001) and at 36 to 38 weeks (P = .001). GDM was diagnosed in 51 (20.4%) women in the control group and 34 (13.6%) women in the IG. The MedDiet significantly reduced GDM incidence (P = .02) after adjusting for confounding factors.ConclusionThe present study shows that dietary intervention in pregnant women, including a MedDiet and increased consumption of EVOO and pistachios, decreases the incidence of GDM. 相似文献
778.
Isolation and properties of an esterase isoenzyme of rat serum 总被引:1,自引:0,他引:1
S R Choudhury 《The Histochemical journal》1974,6(4):369-372
779.
780.
A Choudhury 《Folia primatologica; international journal of primatology》1989,52(1-2):88-92