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991.
992.
993.
The subject of analysis was the data on +3 and +5 Gz tolerance of 130 civilian non-pilot applicants for cosmonauts (men and women, aged 23 to 55) gathered over the past 30 years. Length of the centrifuge arm was 7.25 meters and the total number of primary centrifuge runs was 309. For nearly every second of the applicants (46.7%) acceleration at +5 Gz was an ordeal causing distinct vascular or coronary decompensation. Thus, 29.7% exhibited various combinations of brief visual disturbances, tachycardia, tachypnea, and systolic arterial pressure in the shoulders; in 17%, visual disturbances and/or their precursors were combined with exaggerated cardio-vascular functional parameters, arrhythmia, and serious vegetative disorders. Most of those who had failed to endure the first centrifugation were unable to improve G tolerance during next runs; indeed, they showed negative G-tolerance dynamics. G intolerance grew in significance or was exacerbated by new disorders and their combinations. These results testify against exposure of non-pilot applicants for cosmonauts to +5 G, during the primary medical screening.  相似文献   
994.
作者报道2例确诊的慢性丙肝病毒感染患者合并获得性大疱性表皮松解症(EBA)。两例患者临床上均表现为典型EBA,包括皮肤脆性增加及自发和继发于外伤后发生皮肤水疱,继而以粟丘疹和瘢痕愈合。EBA常常是一种免疫状态改变或低下的疾病。还需进一步研究在这两例患者中和一般情况下丙肝病毒是否诱发EBA。  相似文献   
995.
996.
The effect of storage of platelets in a new polyvinyl chloride (PVC) plastic material with a butyryl-n-trihexyl citrate (BTHC) plasticizer (PL 2209) was evaluated. The PL 1240 container, i.e. PVC plastic with a different plasticizer, tri-(ethylhexyl)-tri-mellitate, was used as a reference. Measurements of pH, pO2, pCO2, glucose, lactate, adenosine triphosphate, total adenine nucleotide content, lactate dehydrogenase and platelet factor 4 (PF4) were made during 5 days of storage. Similar results were noted comparing PL 2209 and PL 1240. Differences in pO2 and pCO2 indicate greater gas permeability in PL 2209 than in PL 1240. Significantly higher PF4 levels were found in PL 2209, but the difference could not be attributed to the PL 2209 container itself. Paired autologous reinfusion studies (111Indium) of 6 normal donors gave mean recovery values after 5-day storage of 41.1 +/- 7.4% (PL 2209) and 45.5 +/- 7.7% (PL 1240), t1/2 66 +/- 13 and 75 +/- 5 h, survival time (linear model) 6.3 +/- 1.0 and 6.8 +/- 0.7 and survival time (multiple-hit model) 6.0 +/- 0.7 and 6.5 +/- 0.4 days, respectively. Only the difference in survival time (multiple-hit) was significantly higher in PL 1240. The corrected count increments at 12-24 h following transfusion were 13,300 +/- 10,800 (PL 2209) and 13,600 +/- 11,600 (PL 1240) with no statistically significant difference found. These results indicate PL 2209 as an equivalent alternative to PL 1240 for the 5-day storage of platelets.  相似文献   
997.
998.
Summary We report a case of a male patient suffering from a severe hemorrhagic radiation proctitis which gradually ceased with hyperbaric oxygen. We discuss the mechanisms of chronic radiation injury and the effect of the hyperbaric oxygen. This therapy is proposed as an alternative to surgical intervention for this abnormality.  相似文献   
999.
1000.
Previously we have shown that expression of the insulin-like growth factor II (IGF-II) gene in 36 normal smooth muscle tissues (myometria) and 26 benign smooth muscle tumors (leiomyomas) was detectable by Northern blot analysis but that the RNA levels were low. In 9 of 20 malignant smooth muscle tumors (leiomyosarcomas) IGF-II gene expression was also low or absent, while in 11 of 20 the IGF-II gene was abundantly expressed. In 32 of these tissues we have now studied the DNA methylation state of the IGF-II gene. For the analysis of overall methylation of the gene the restriction endonucleases HpaII and MspI were used. In normal smooth muscle and in leiomyomas the IGF-II gene appeared to be methylated. In leiomyosarcomas with low IGF-II gene expression the DNA was partly demethylated. In leiomyosarcomas with abundant IGF-II gene expression overall methylation of the DNA tended to be low. In addition, we have studied the methylation state of one particular CpG site in the IGF-II gene with the restriction endonuclease AvaII. The results of the latter analysis confirm the analysis with HpaII and MspI. In conclusion, in malignant smooth muscle tumors the data indicate an inverse correlation between CpG methylation and expression of the IGF-II gene.  相似文献   
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