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Knowledge about cause, pathogenesis, and manifestations of hereditary metabolic diseases puts them among the best known of all human diseases. On the other hand, outcomes of treatment are cause for uncertainty and concern. In 1985, Hayes et al. analyzed efficacy of treatment up to 1983 in 65 of these diseases selected randomly from the McKusick catalogs. Disease scores were calculated for seven parameters: longevity; reproductive capability; somatic and cognitive development; and handicaps affecting schooling, work, and cosmetic appearance. Scores of the untreated and treated phenotypes were then compared. We have now measured progress over the past decade by calculating scores on the same 65 diseases from data in several hundred new reports published since 1983. All seven parameters in the 1993 survey reflect improved efficacy of treatment in the 10-year interval. However, the percent of diseases for which all manifestations of the disease were removed by treatment has not changed (12% in 1983; 12% in 1993). The group in which manifestations were untouched by treatment has become smaller (48% in 1983; 31% in 1993), and the group partially ameliorated by treatment had increased reciprocally (40% in 1983; 57% in 1993). Progress in the treatment of hereditary metabolic disease is thus better than it was, but it is still only a partial success. The advances are attributable to greater success with organ and tissue transplantation, better pharmacotherapy, and better support systems. Restoration of normal homeostasis, the key to successful treatment, remains an elusive challenge and is a logical, major focus for research in human genetics.  相似文献   
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A rapid bioassay was developed to measure the bioherbicidal efficacy of spore preparations of the pathogens Colletotrichum truncatum (Schwein.) Andrus and W. D. Moore and Alternaria cassiae Jurair and Khan on hemp sesbania (Sesbania exaltata) and sicklepod (Cassia obtusifolia), respectively. The system uses 4-day-old dark-grown seedlings (grown hydroponically in paper towel cylinders) which were sprayed with spore suspensions. Shoot lengths were monitored non-destructively, and recorded over time under conditions of dark growth, 90-100% relative humidity and 25 C. Shoot growth inhibition and stem collapse (mortality) were directly related to the spore concentration applied. Generally, at 10 3 - 10 4 spores ml-1, these pathogens caused significant shoot growth inhibition within 25-30 h and seedling death within 40-50 h. This bioassay has been used to study herbicide-pathogen interactions, and may be extended to determine the bioherbicidal efficacy of different pathogen isolates, pathovars or spore formulations. This technique is more rapid, uses a lower inoculum volume, requires less space and is performed under more controlled conditions than conventional greenhouse bioassay methods. The data obtained are more quantitative than those obtained from bioassays relying on visual rating systems.  相似文献   
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The content of proteins, lipids and carbohydrates and the calorific contents in six Antarctic and three south Chilean brown algae were determined. These constitute the first reports of chemical composition in the endemic Antarctic species Cystosphaera jacquinotii, Phaeurus antarcticus and Desmarestia antarctica. There were no marked differences in total energy levels between Antarctic and cold-temperate species (values between 10.6 and 13 kJ g–1 dry weight). However, species such as Adenocystis utricularis showed significantly higher ash-free energy (26.3 kJ), which is explained in terms of morpho-functional differentiation. Ascoseira mirabilis and Phaeurus antarcticus showed high total lipids (2.1–2.2% dry weight) and soluble carbohydrates (5.9 and 3.4% dry weight). In general, algae from Chile had similar energy levels and no obvious differences in organic content could be found.  相似文献   
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Mitotic spindles constitute the machinery responsible for equidistribution of the genetic material into each daughter cell during cell division. They are transient and hence quite labile structures, changing their morphology even while performing their function. Biochemical, immunological and genetic analyses of mitotic cells have allowed us to identify a variety of molecules that are recruited to form the spindle at the onset of mitosis. Evaluation of the roles of these molecules in both the formation and in the dynamics of spindle microtubules should be important for understanding the molecular basis of mitosis and its regulation. We have recently identified a novel mitosis-specific microtubule-associated protein (MAP) using a monoclonal antibody probe raised against the mitotic spindles isolated from cultured mammalian cells. This 95/105 kDa antigen represents a unique component of the spindle distinct from any of the other MAPs reported so far. Antibody microinjection resulted in mitotic inhibition in a stage-specific and dose-dependent manner, indicating that the protein is an essential spindle component.  相似文献   
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