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991.
One hundred twelve consecutive fractures of the femoral diaphysis were treated in a prospective study at Grady Memorial Hospital, a designated trauma center, during the three-year period 1978 through 1980. Fifty of these were treated by closed intramedullary nailing; all united. Of the rest, 20 were treated by modified open intramedullary nailing, and 42 by cast-bracing. Closed intramedullary nailing offered a significant reduction in hospitalization and healing times compared to the other two methods; however, the high cost of equipment, along with the added cost of reoperation to remove the nail, rendered cast-bracing economically superior. Fractures treated by modified open intramedullary nailing developed no infections, but these patients lost significantly more blood during operation than those treated by closed nailing. Because of the decreased hospitalization and healing times, we prefer the closed intramedullary nailing technic for use in selected femoral fractures treated during the acute phase by an experienced surgical team.  相似文献   
992.
This paper reviews the results of some experimental tests carried out to evaluate the performance of selftuning (ST) controllers for temperature control of a continuous stirred tank heater, composition control of a binary distillation column and pH control of an acidic effluent. All the pilot plant units have been controlled using a single variant selftuning control, and a newly developed multivariant ST controller was used for simultaneous control of the terminal compositions of the distillation column. The control performance of the units operating under ST control is compared to that obtained using very well tuned proportional plus integral (PI) or proportional plus integral plus derivative (PID) conventional controllers. Control of pH is shown using a technique of electrochemical neutralisation coupled with a single variant ST controller. The control algorithms have been programmed on a number of microprocessor- and minicomputer-based systems. Z80 for stirred tank heater control, LS1-11 for pH control and HP1000 distributed computer system for distillation control.  相似文献   
993.
Single subcutaneous injection of 1500 IU human chorionic gonadotropin or placebo injections were given at the time of insemination in lactating dairy and beef cows to determine their effects on rates of pregnancy. Pregnancy rates at first service in 161 control and 145 treated dairy cows were 52.8% and 44.8%, respectively. Similar rates for 136 control and 145 treated beef cows were 54.4% and 54.5%. Injections of human chorionic gonadotropin were not effective in stimulating conception rates in lactating dairy or beer cows under field conditions.  相似文献   
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Herpes simplex encephalitis in a 21-year-old man presented as a flu-like illness, followed by inappropriate behaviour, drowsiness and focal neurologic signs. Investigations indicated a lesion in the right temporal lobe. The diagnosis was confirmed by isolation of the virus from a cerebral biopsy. Pronounced clinical improvement was noted when cytosine arabinoside therapy was started in the postoperative period. This report supports the observation by some authors that cytosine arabinoside may be of value in the treatment of herpes simplex encephalitis.  相似文献   
999.
The decrease of functional capacity of cellular immunity during ageing seems to be due to cellular changes of stem cells, particularly in the growth properties and the cell density in T-cell subsets. We approached this problem at the molecular biological level by quantifying the key enzymes necessary for DNA synthesis in bone marrow cells from mice: deoxynucleotidyl transferase (TdT) and DNA polymerase alpha. The bone marrow cells were fractionated on a discontinuous bovine serum albumin density gradient and the extractable enzyme activities (expressed per 10(8) nucleated cells in the respective fraction) were determined. TdT activity was found to decrease markedly during ageing. Mature animals contain only 34% and senescent animals only 13% of the activity observed in immature mice. From the density distribution analysis it was found that a shift of TdT-containing cells to the lower density occurs. The specific DNA polymerase alpha activity also decreases in bone marrow cells with age. While the overall activity amounts in immature cells to 78 enzyme units/10(8) cells, it decreases in mature cells to 57 units/10(8) cells, and in cells from senescent animals to 36 units/10(8) cells. Density distribution analysis of the cells shows that the highest activity is observed in the low-density fraction. From these experimental data we conclude that in the fractions containing precursor T-cells, a reduced number of proliferating cells is present.  相似文献   
1000.
We studied androgen production by morphologic and biochemical criteria plus androgen binding by skin fibroblasts in 13 male pseudohermaphrodites and 13 males with micropenis, none of whom had evidence of androgen insensitivity. Seventeen of the 26 patients had evidence of deficient androgen production, suggesting this as the cause of their incomplete virilization in utero. Fibroblasts from all 26 patients demonstrated normal androgen binding and affinity of the steroid for the receptor. Although these results exclude a deficiency of androgen binding in these individuals, other end organ defects are possible. Guidelines for diagnosis and management of such patients are presented.  相似文献   
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