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991.
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   
992.
The importance of controlling the bioburden in wounds can not be over emphasized. Glycerine based gel sheets have been used extensively to show their bacteriostatic/fungistatic properties. Hoekstra studied animal wounds and compared glycerine dressings with water based dressings and the glycerine showed superior bioburden reduction. Vandeputte showed similar results when comparing hydrogel and hydrocolloid dressings and looked at the histology of the wounds to find differences in the quantities of the types of cells present. The reduced scar formation of wounds are thought to be attributed to the influence of the glycerine on the healing process. Hoestra has reported the dramatic reduction in the inflammation reaction soon after application of the glycerine gel dressing. Studies by Oliveria‐Gandia, Davis, and Mertz showed the glycerine dressings to be more effective than hydrogel or hydrocolloid dressings in reducing bioburden in animal wounds that were inoculated with microbes and also reducing biocounts in appropriate growth medium. Vandeputte conducted a diabetic study(no exclusions) that compared the glycerine dressing (n = 15) with standard protocol(n = 14) for diabetic foot wounds, that showed the test dressing to be far superior. He along with thousands of other nurses around the world have reported the use of glycerine dressings on superficial burns to reduce pain, reduce the chance for infection, reduce scar formation, and to protect the wound from friction and pressure. J. Baksa extensively used the glycerine gel sheets in his burn unit not only for the superficial wounds but also for 3rd and 4th degree burns on children as well as after surgical removal of hypertrophic and keloid scars to prevent reoccurrence. T.M. Baum and M.J. Busuito also reported the use of the glycerine dressing for scar prevention and treatment. The glycerine dressing has been used extensively for te treatment and prevention of pressure ulcers in hospitals, nursing homes, athletic fields, as well as, under casts, splints and braces. R. Horchner reported a >95% reduction in pressure ulcers in a direct comparison to the control and to hydrocolloids.  相似文献   
993.
994.
胆汁CEA和CA72-4联合检测对胆管癌的诊断价值   总被引:3,自引:0,他引:3  
胆管癌术前的定性诊断十分困难。检测胆汁肿瘤标志物是一条可研究的途径。本文探讨胆汁癌胚抗原(CEA)和糖类抗原72-4(CA_(72-4))联合检测对胆管癌的诊断价值。 1.材料和方法:研究对象来自本院自1999年1月至2002年4月收治的66位病人,胆管癌32例(男20例,女12例),胆管良性病变34例(男15例,女19例)。术前经ENBD或PTCD、术中直接穿刺胆管收集胆汁。经超速离心15 min后,取上清液5 ml,—20℃存放。  相似文献   
995.
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   
996.
Immunization of BALB/c mice with natural purified HIV antigen, fusion of spleen cells with myeloma cells and subsequent selection of hybrid clones using recombinant gag antigen of HIV gave hybridomas producing monoclonal antibodies (MCA) to HIV. The immune blotting method demonstrated that 3 clones interacted with protein p24 and 4 clones with protein p17 of HIV. Competitive EIA led to a conclusion that the resulting MCA detected at least 3 antigenic determinants in proteins, products of gag gene of HIV. The potentials of using these MCA for the detection of viral antigen in HIV-infected continuous cell lines were demonstrated.  相似文献   
997.
Fifty–five children 6–16 years old with allergic rhinoconjunctivitis due to both birch and grass pollinosis were randomized into 2 parallel groups, treated in double–blind fashion with either levocabastinc (LEV) eye–drops twice daily plus placebo eyedrops twice daily or sodium cromoglycate (SCG) eyedrops 4 times daily for 3 months. Spersallerg® (antazolini chloride + tetryzolini chloride) eyedrops were allowed as rescue medicine. All children received basic treatment with an antihistamine (terfenadine) during the complete trial period, and a local nasal corticosteroid if needed. Eye symptoms were recorded daily by the patients and at 4 visits by the investigator, at start and after 4, 10 and 13 weeks. Pollen counts were performed and a blood sample was collected at start and end of the treatment. The global evaluation of treatment was similar for the 2 groups, and there was no significant difference in any effect parameter except for the symptom, itchy eyes, which had lower score in the SCG group as evaluated by the investigator after 4 weeks. On days with low pollen counts the patients in the SCG group had fewer days with moderate or severe eye symptoms. It is concluded that even though LEV and SCG eyedrops were given in addition to systemic treatment with an antihistamine, no consistently significant differences in clinical effect were found between the 2 treatment groups, but the SCG group experienced slightly less eye symptoms throughout the trial. LEV eye–drops appear safe in long–term treatment in children, and no signs of tachyphylaxis were recorded.  相似文献   
998.
The purposes of the present study of chronic pain patients were to (a) assess whether cognitive and behavioral coping style is related to personality factors, (b) assess how coping styles differ across personality types, and (c) assess how outpatient interdisciplinary intervention affects the coping styles of various personality types. Four MMPI clusters (Depression/Pathological, V-type, Marginal Depression, and Marginal V-type) were derived using a hierarchical clustering procedure. Seventy subjects also completed the Coping Strategies Questionnaire before and after a 3-week outpatient pain management program. Pretreatment analyses indicated the Depression/Pathological and Marginal Depression groups used diverting attention less than either V-type group. The V-type group reported using praying/hoping significantly more than either of the marginal groups. At posttreatment the Depression/Pathological group used catastrophizing significantly more than either of the marginal groups. Results of pre-post analyses indicated that the Depression/Pathological group increased their use of diverting attention, reinterpreting pain sensations, and ignoring pain sensations, while decreasing catastrophizing. The V-type group increased their use of reinterpreting pain sensations, while decreasing praying/hoping and catastrophizing. Neither of the Marginal subtypes showed significant pre-post changes in coping strategies. These results suggest that different personality types use different pain coping strategies prior to multidisciplinary treatment. Groups showing more severe psychological distress, perhaps related to an underlying personality disorder, displayed greater changes in coping strategies with treatment, but remained more dysfunctional after treatment. These findings suggest that the alteration of coping strategies may be an important treatment effect needing more individualization to maximize treatment response.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
999.
Histological studies describe in detail the changes of the small arteries wall with controversial results concerning lumen narrowing during the aging process. In this study, the anatomic and the angiographic parameters of the medial and lateral lenticulostriate arteries were analysed in 64 carotid angiograms. Only 20% of the total number of lenticulostriate arteries were shown on angiograms. Collateral branches were rarely visible, especially those of medial group. The course of the lenticulostriate arteries was mostly straight or moderately tortuous. No significant differences were noted in any of the measured parameters when compared with the age (p greater than 0.05). It appears that age-related changes spread over external layers of small arteries, with no lumen narrowing or filling defect.  相似文献   
1000.
J Strausz  S Kis  J Juhász  A Bede  J Elek  Z Monostori  G Nagy  I Repa 《Orvosi hetilap》1992,133(36):2293-2296
Six patients with obstruction of the trachea were treated with silicone rubber endothracheal stents implanted with flexible bronchoscope. In every case the stent caused significant clinical improvement of the ventilation. At the postintubation stenosis the stent can result a final recovery, at the malignant processes the implantation seems to be a new palliative method.  相似文献   
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