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991.
A new technique of scanning electron microscopy for visualization of hidden cellular surfaces in organs and tissue has been developed. It employs the sample incubation in 30% potassium hydroxide and 96% alcohol mixed in equal amounts and dissociation until single cells appear in the solution, this being checked under phase-contrast microscope. The method is beneficial in non-standard cases of three-dimensional organization of organs and tissues. 相似文献
992.
R. J. Rona A. V. Swan R. Beech D. M. Wilson F. B. Kavanagh C. Brown C. Axtell S. Mandalia 《Clinical genetics》1992,42(4):186-195
For certain genetic conditions DNA testing identifies carriers and determines the risk status of foetuses, thus helping parents to make more informed prenatal decisions. Data, collected from three genetic centres in England and Wales from August 1986 to July 1990, are used to describe trends in demand for DNA testing, the impact of DNA tests on carrier risk assessment, and the use of DNA tests in relation to pregnancy outcome. Altogether the data include 23,388 subjects and 681 pregnancies in 8738 families divided into five cohorts by year of entry and referral. The most frequent gene disorders referred to the genetic centres are currently being tested or will soon be tested. For these disorders the initial high level of activity has declined and may have reached steady state. Demand for DNA services is high for cystic fibrosis and Duchenne muscular dystrophy, intermediate for Huntington's disease, and low for adult polycystic kidney disease, phenylketonuria and tuberous sclerosis. Based on these findings we suggest that demand for DNA tests will be high in serious, untreatable and slow progressing conditions with early onset; intermediate for conditions affecting intellect and neurological integrity with later onset; and low for treatable, late-onset conditions, or those for which there is evidence of heterogeneity, and variable penetrance. It would be helpful to assess the extent to which this view of demand is confirmed when the new disorders being DNA tested are considered and for the pattern of activity of DNA testing for some types of cancer. Since no DNA centre could offer a fully comprehensive testing service, it is recommended that a structure is created to audit overall activity, assist in policy formulation, and influence supraregional service organisation, in order that the spread of DNA services be planned as effectively as possible. This structure would facilitate monitoring of the evolution of contract specifications agreed by commissioners and providers on a regional basis. 相似文献
993.
Scientific-Research Institute for Medical Instrument Engineering, Moscow. Translated from Meditsinskaya Tekhnika, No. 6, p.
8, November–December, 1992. 相似文献
994.
F. R. Robert H. Martens N. Cormann A. Benhida J. Schoenen V. Geenen 《Clinical & developmental immunology》1992,2(2):131-140
Neuropeptide signals and specific neuropeptide receptors have been described in the
thymus supporting the concept of a close dialogue between the neuroendocrine and the
immune systems at the level of early T-cell differentiation. In this paper, we review
recent data about neurohypophysial (NHP)-related peptides detected in the thymus
from different species. We suggest that we are dealing in fact with other member(s) of
the NHP hormone family, which seems to exert its activity locally through a novel
model of cell-to-cell signaling, that of cryptocrine communication. This model involves
exchange of signals between thymic epithelial cells and developing thymocytes. The
NHP-related peptides have been shown to trigger thymocyte proliferation and could
induce immune tolerance of this highly conserved neuroendocrine family. 相似文献
995.
Scientific-Research Center of Biomedical Radioelectronics, Moscow. Translated from Meditsinskaya Tekhnika, No. 6, pp. 36–37,
November–December, 1992. 相似文献
996.
Scientific Research Institute for Radiomeasuring Equipment, Kiev. Translated from Meditsinskaya Tekhnika, No. 2, pp. 21–24, March–April, 1992. 相似文献
997.
998.
F M Ga?nutdinov V M Timerbulatov 《Klinichna khirurhiia / Ministerstvo okhorony zdorov'ia Ukra?ny, Naukove tovarystvo khirurhiv Ukra?ny》1992,(2):45-47
The data on incidence of detection of associated rectal diseases--hemorrhoids and anal fissures--are presented. The indications for operative treatment are considered, a method suggested by the authors for surgical treatment of the mentioned diseases, which was used in 62 patients, is described. Use of the improved operative technique contributed to reduction in number of complications. Duration of treatment has shortened by 7 days. 相似文献
999.
1000.
Z. S. Meharwal N. Trehan V. M. Kohli V. K. Sharma R. R. Kasliwal A. Mishra V. Kohli A. Jayant 《Indian Journal of Thoracic and Cardiovascular Surgery》1992,8(2):88-91
Between November 1988 and February 1992, 416 patients required coronary endarterectomy for diffuse coronary artery disease.
This constitutes 16.19 per cent of all patients who underwent coronary artery bypass grafting during the same period. A total
of 528 endarterectomies were performed. Four-hundred and twenty-two endarterectomies were performed on right coronary system
and 106 endarterectomies were performed on left coronary system. One-hundred and twelve (26.92%) patients required more than
one endarterectomies.
The hospital mortality was 2.16 percent. 3.37 per cent of patients had perioperative infarction. Intraaortic balloon pump
was required in 1.92 per cent of patients. 5.77 per cent of the patients had significant arrhythmias. The patients have been
followed up for a mean period of 27 months. One-hundred and forty patients were evaluated by exercise multigated radionuclide
angiogram. One-hundred and thirty-four (95.71%) patients showed increase in ejection fraction as compared to preoperative
value. Six (4.29%) patients did not show any significant change while eight (5.71%) patients had fall in ejection fraction.
Postoperative coronary angiogram was done in 44 patients at a mean of 10 months. 89.59 per cent of grafts to the endarterectomised
vessels and 91.67% of grafts to nonendarterectomised vessel were patent. The difference between the two groups was not statistically
significant. 相似文献