The prevalence of Echinococcus granulosus and other taeniid cestodes in sheep dogs of central Utah

Fifty-one of 62 sheep dogs in central Utah were successfully purged for diagnosis of cestodes in 1981. Tapeworms were identified in the purged fecal samples of 33 (64.7 percent) animals. Minimum infection rates in the dogs which were purged were; 9.8 percent for Echinococcus granulosus , 29.4 percent for Taenia pisiformis , 27.5 percent for T. ovis krabbei , 27.5 percent for T. hydatigena , and 2.0 percent for T. serialis . The prevalence of E. granulosus decreased from 27 percent in 1971 to 9.8 percent in 1981.     

New brachiosaur material from the Late Jurassic of Utah and Colorado

Little is known about the Brachiosauridae, which includes some of the largest known sauropods, such as the genus Brachiosaurus , discovered in western Colorado by Elmer S. Riggs in 1900. Additional diagnostic material, previously unknown in the western hemisphere, is reported from three comparatively recent quarries: the Jensen/Jensen Quarry in eastern Utah and the Dry Mesa and Potter Creek quarries on the Uncompahgre Upwarp in western Colorado. An unknown, well-preserved, articulated sauropod atlas/axis, seven cervical vertebrae, and an interesting flora were associated with the Potter Creek Quarry brachiosaur material. Taphonomic factors in that quarry are noted. The Jensen/Jensen and Dry Mesa deposits occur in basal sediments of the Bushy Basin Member of the Morrison Formation, and the Potter Creek Quarry in an intermediate section of that member.     

Soil characteristics of mountainous northeastern Nevada sagebrush community types

Soil physical and chemical properties were studied to identify habitat differences among 15 sagebrush dominated plant community types of the Great Basin. The sagebrush taxa studied followed an apparent gradient of increasing soil fertility, with Artemisia nova commonly occupying the lowest fertility sites. Sites of moderate soil fertility tended to support A. arbuscula , A. longiloba , and A. tridentata ssp. Wyomingensis . Artemisia tridentata ssp. Tridentata and A. tridentata ssp. Vaseyana were commonly found on sites with the highest soil fertility levels as indicated by maximum organic carbon, nitrogen, and phosphorus levels within such soils. Mollic epipedon depth, total depth, and water-holding capacity of the soil also increased as the dominant sagebrush taxon of a community type changed from A. nova to A. tridentata ssp. Vaseyana . Data from this study provide information concerning soil relationships within relatively undisturbed rangeland communities. Such data are required if future soil sampling efforts within the Great Basin are to have a basis for comparison.     

Interference of hydrazine derivatives with the tyrosinase-tyrosine reaction]

A comparative study of the tyrosinase-tyrosine reaction, using both oxygen-consumption determination and spectrophotometric methods, shows that hydrazine derivatives inhibit melaninogenesis at different steps.     

Evolutionary implications of different types of microbial enzymology for L-tyrosine biosynthesis.

Several patterns of enzymology for L-tyrosine biosynthesis exist in modern microorganisms, each differing in the apparent degree of regulatory efficiency. The extent of pathway evolution in a particular organism may reflect the relative selective pressure for regulation encountered in different ecological niches.     

Cells on chips

Microsystems create new opportunities for the spatial and temporal control of cell growth and stimuli by combining surfaces that mimic complex biochemistries and geometries of the extracellular matrix with microfluidic channels that regulate transport of fluids and soluble factors. Further integration with bioanalytic microsystems results in multifunctional platforms for basic biological insights into cells and tissues, as well as for cell-based sensors with biochemical, biomedical and environmental functions. Highly integrated microdevices show great promise for basic biomedical and pharmaceutical research, and robust and portable point-of-care devices could be used in clinical settings, in both the developed and the developing world.     

急性肝功能衰竭的猪动物模型

目的：建立一个比较接近人类条件的急性肝衰竭模型。用于人工肝脏治疗的疗效和安全性的测试。方法：以右旋半乳糖来制造猪肝衰竭的大型动物模型,分组３组给药,剂量分别为０．５、１和０．７５g/kg。观察其临床表现、生理生化指标和病理改变。结果：３组实验都能引出与人的临床和生化指标变化相伫的肝功能衰竭的表现,以０．７５g/kg组最为理想。结论：以０．７５g/kg的半乳糖胺制造的急性肝功能衰竭的猪动物模型,符合人工肘脏研究对动物模型的要求。