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91.
Growth indices were examined in 24 identically managed tanks, each containing 120 diploid juvenile rainbow trout (initial mean body weight, 9.3 g) during a 12-week study to examine tank effects associated with tank location in a multi user research facility. Growth indices included mean body weight, feed intake, feed conversion index, and specific growth rate. The null hypothesis that tank effect had no effect on growth over the 12-week period was rejected (P = 0.038), and mean weight in individual tanks differed by as much as 18.7%). During the study it was determined that the proximity of tanks to common-use walkways in the facility could affect growth indices. This was indicated by significant differences in the mean fish weights among blocks of tanks served by different header tanks after 4 (P = 0.001) and 8 (P = 0.024) week. The block containing tanks of fish with the highest them weight was nearest to the 2 common-use walkways in the facility. Fish in this block of tanks, compared with those in other blocks, had significantly greater feed intake but no significant differences in conversion efficiency. Compensatory growth, a well known growth attribute in fishes, diminished the difference in mean weight be tween these blocks of tanks by the end of the study. Comparison of paired ranks within header tank blocks indicated that fish in those located nearest to walkways had higher feeding rates over the 12-week period (P = 0.048), but less efficient feed conversion (P = 0.040) than did fish in matched tanks located farthest from walkways. However, there were no differences in mean weight of fish. Results of this trial document the risks involved in identifying fish in a tank as the experimental unit when treatments are administered to the tank of fish, the latter being the true experimental unit.  相似文献   
92.
The nutritional status of 75 maintenance hemodialysis (MHD) patients was evaluated according to the dietary intake analysis, anthropometric measurements, biochemical and immunological parameters in this study. Furthermore, some possible factors which would affect nutritional status of hemodialysis patients were discussed. The results showed that hemodialysis patients demonstrated a high incidence of malnutrition. The low intake of protein and calorie, metabolic acidosis and inadequate dialysis would worsen the malnutrition while erythropoietin treatment improve the nutritional status of hemodialysis patients. Based on these results, suggestions were proposed for the improvement of nutritional status of MHD.  相似文献   
93.
We have prepared a panel of lipidic ammonium tetrafluoroborate salts that contain trifluoromethyl, trichloromethyl, and methyl groups attached to the headgroup. 19F-NMR analyses of the cationic lipid panel revealed that the differences in electron-withdrawal from the ammonium ion headgroup accounted for differences in ion-pairing. Exchange of the tetrafluoroborate counterion by complexation to DNA-phosphate of a reporter gene enabled us to probe the influence of inductive electron-withdrawal in cationic lipid-mediated DNA transfection. We tested the lipid panel for transfection activity in two cell lines. The results indicate that the inductive effects of electron-withdrawing functionality diminish transfection activity in modest (2-4-fold) increments. The present study suggests that the mechanism whereby poly(alcohol)- or poly(ether)-substituted headgroups improve DNA transfection is not based on electronic activation of the ammonium ion.  相似文献   
94.
Deep brain stimulation (DBS) of the thalamus reduces tremor in patients with essential tremor (ET). However, few studies have determined the degree of improvement in daily functioning associated with DBS. We developed a self-report Tremor Activities of Daily Living Scale (TADLS) to compare daily functioning with the stimulator turned on and off. Patients rated their performance on the 30 items of the TADLS with the stimulator turned off and then on. They also performed 10 activities under the supervision of a clinician who rated their functional ability with stimulation off and then on. There was a 58% improvement in self-rated TADLS scores in patients with DBS with the stimulator on compared with stimulation off. When activities were rated by the clinician, the average improvement in functioning with the stimulator on was 54%. There were reasonably high correlations between patient and clinician ratings of functioning. ET patients have a marked improvement in daily functioning with thalamic DBS.  相似文献   
95.
Forty-nine term infants were prospectively shown to have hypoxic-ischemic encephalopathy (HIE). All infants survived the neonatal period, and all but two infants (seen at 12 months) were followed up to at least 27 months of age. Factors that significantly correlated with outcome included the Sarnat encephalopathy stage and the occurrence of intractable seizures not controlled by phenobarbital sodium alone. There was no association between the one- or five-minute Apgar score, the need for early ventilation, the EEG, the occurrence of seizures, and the subsequent outcome. There was no significant difference in outcome for those infants who received dexamethasone sodium phosphate (n = 29) v those who did not receive the drug (n = 20). A review of 97 term infants with HIE from a regional perinatal program during a one-year period (1979), including 35 of the 49 infants in the present study, did show a significant increase in morbidity and mortality for transported infants.  相似文献   
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The mode of inheritance of susceptibility or refractoriness of insect vectors to medically important pathogens such as those causing malaria or filariasis is usually believed to follow normal Mendelian laws and to involve a single pair of alleles. In this report, experiments are described that demonstrate another mode of inheritance of mosquito susceptibility to filarial parasites. Crosses were made between susceptibile and refractory species of the Aedes Scutellaris complex, and the hybrid and backcross progeny were tested for susceptibility to infection by Brugia malayi and Brugia pahangi. The data indicate that inheritance follows a non-Mendelian pattern indicative of extrachromosomal factors inherited through the maternal parent.  相似文献   
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Abstract

Towns and cities in India are facing complex problems regarding the provision and maintenance of services and infrastructure in the face of the rapid growth of pupulation, caused both by natural increase and migration. In order to meet such challenges a planner needs to have fairly accurate and up-to-date information, especially about physical structures and related land parameters. A study of their trends generally helps in the understanding of the emerging growth pattern and in formulating policies to guide or redirect it. Recent advances in the field of remote sensing technology and computer based Geographical Information Systems (GIS) provide very useful tools in undertaking such analysis. The results from a study about growth trends of the urban areas in the Bombay Metropolitan Region using multi-date remote sensing data and ARC/INFO GIS package are described here. The period under consideration is from 1968 to 1989. It should be noted that the major growth in the region is confined to Greater Bombay between 1968 to 1975. After the year 1975, a distinct outward growth along the rail corridors is visible. Growth after 1975 is mainly in the Kalyan, Bhiwandi, New Bombay and Panvel areas and in the area around Manori creek (Charkop area). The growth rate is found to be higher after the year 1975 compared to the prior growth rate. The spatial growth trends are examined in relation to the population and the population density has been computed for different periods. Based upon these densities, the extent of land required for urban development for the year 2001 has been calculated. Suitability of land for urbanisation has been carried out based upon physical characteristics of the land and environmental parameters. The priority areas of urban development to meet the additional requirement in 2001 have been identified on the basis of this suitability analysis. A map on a 1:250000 scale has been prepared to show the areas for urbanisation which will meet the demands for the year 2001. This study demonstrates the potential offered by the integration of the tools of remote sensing and GIS for urban and regional planning.  相似文献   
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