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Antenatal diagnosis of hereditary disease is highly dependent on sufficient theoretical knowledge and on a number of practical methods of studying the foetus such as obtaining, cultivating and assaying amniotic fluid cells. Knowledge of the primary defect in any monogenic disorder cannon be used in prenatal diagnosis unless the metabolic error is expressed in vitro. Modern cytogenetics can diagnose in utero a large majority of karyotyping abnormalities although the karyotype-phenotype correlation is not an absolute one. This task must be assigned to special laboratories where technical pitfalls are reliably avoided. In both metabolic and chromosomal hereditary disease, the pathologist can confirm and extend the phenotypic findings and improve knowledge on foetal features and physiopathology. Pathology is the more important, the less means of in utero diagnosis are available as in the non-chromosomal syndromes of localized or multiple malformations. Here it helps eliminating a present major drawback of prenatal diagnosis: the lack of a strict diagnosis in the previous patient in a family at risk.  相似文献   
76.
A new interpretation of previous work (Bukolova-Orlova, T. G., Burstein, E.A. and Yukelson, L. Ya (1974) Biochim. Biophys. Acta 342, 272-280) and some new data on the luminescence of neurotoxins I and II from Naja oxiana venom is given, based on the newer data on their complete amino acid sequences. Very effective excitation energy exchange exists between Trp-27 and Trp-33 in neurotoxin I and between Trp-27 and Trp-28 in neurotoxin II, Which results in the tryptophanyl fluorescence spectra of each of the proteins seeming to be monocomponent ones. The lowered fluorescence quantium yield value, the shortened phosphorescence lifetime (80% of the emission has tau p less than 0.5 s, 20% has tau p = 4.8 s, comparing with usual tau p = 5.5-5.9 s) and decreased phosphorescence to fluorescence ratio (0.042, as compared to the usual 0.4-0.7) for neurotoxin I suggest that the indole chromophore of Trp-27 and/or Trp-33 are in contact with heavy sulfur atoms of disulfide, most probably of Cys(28)-Cys(32). Tryptophanyls in neurotoxin II are exposed to the solvent, however their accessibility in relation to that of the free tryptophan to the negatively charged quencher I- (0.455) is much higher than that for the positively charged Cs+ (0.08), which is probably due to the proximity of cationic Lys-25, Lys-26 and His-31. The difference of accessibility to the negative and positive quenchers is even more pronounced in the case of the neurotoxin I (1.04 and 0 +/- 0.02, respectively), though in its chromophore vicinity along the primary structure there is only one cationic group, Lys-25. This fact together with the analysis of the amino acid sequence, suggest that the space folding of this polypeptide results in the close proximity of Trp-27 and/or Trp-33 with the C-terminal peptide segment 67-73, which contains four cationic groups (His-67, Lys-69, Lys-71 and Arg-72).  相似文献   
77.
Official physical examinations of migrant workers upon immigration are required before work permits are issued. The screening of 74,983 applicants during 1972 to 1974 revealed sera reactive to serological tests for syphilis in 0-8 per cent. (range 0-5 to 1-1 per cent.) of all persons concerned and fifteen cases of early syphilis. The incidence of recent infections among immigrants is lower than that reported among the inhabitants of Vienna. General statistics on the spread of venereal diseases among immigrant workers are not available after they start work. Some evidence is provided by those who had to be traced for compulsory examination because they had defaulted from treatment or follow-up, because they were suspected of clandestine prostitution, or because they were reported to be sources of infection. 257 (60-6 per cent.) of 414 individuals who were wanted for reasons of syphilis control could be located and eighteen (7 per cent.) of those who were examined had early infectious lesions.  相似文献   
78.
"Zero-loop" of the molecular potential transformer of submitochondrial particles (SMP) is separated from the remaining electron transfer chain by rotenone, and its e.m.f. ET=0,003+RT/2F in [NADP X H] [NAD+]/[NADP+] [NAD X H] volts is used in the compensative method of measurement of the potential difference across the SMP membrane (delta USMP). The phospholipid membrane, measuring the concentration of the penetrating anions in the solution contained SMP, is used as "zero-indicators". This concentration drops monotonically with increase in delta USMP. Delta USMP is equal to ET when the addition of substrates of transhydrogenase reaction with definite ET does not change the potential across phospholipid membrane.  相似文献   
79.
Three hr after i.p. administration of a single dose of 30 mg/kg of morphine to male mice, an increase in specific activity of NADPH-cytochrome c reductase by about 10% and the content of cytochrome P-450 by about 14% of their liver microsomes was observed.Administration of 30 mg/kg of morphine, once daily,during 5 days, caused about 16% and 9% increases in specific activity of c reductase and the content of P-450 respectively. Administration of a single dose of morphine to male and female mice caused no sex-dependent differences in the specific activity of c reductase and the content of P-450. Repeated administration of morphine up to 100 mg/kg to male mice increased the specific activity of microsomal c reductase by about 70%. Repeated administration of morphine up to 55 mg/kg also increased the microsomal content of P-450 by about 22%, but with higher doses of morphine, the content of P-450 declined and finally dropped below control levels. The levels of c-reductase activity and P-450 content returned to normal levels about 2 weeks after termination of morphine administration.  相似文献   
80.
The efficacy of two antithrombotic regimens, combined dextran and aspirin and combined dextran and warfarin, was analyzed by comparing the incidence of thromboembolism following total hip replacement in two groups of similar patients. Of the 427 who received dextran and aspirin, 7 per cent had thromboembolic complications, including one case of fatal pulmonary embolus and one case of recurrent emboli that required vena caval ligation, and 15 per cent had wound-healing complications. Of the 197 patients who received dextran and warfarin, 5 per cent had thromboembolism and 24 per cent had wound healing complications. Although both prophylactic regimens seemed effective, dextran and aspirin appeared less effective in reducing thromboembolic complications than dextran and warfarin, but there were fewer wound complications in that group. One-fourth of the patients on dextran-warfarin were not adequately anticoagulated despite close supervision. In forty-five patients with a history of thromboembolism who were excluded from the study and analyzed separately, warfarin alone and the two described regimens were equally ineffective in preventing thromboembolism, and the incidence of thromboembolic complications was high. Dextran-aspirin and dextran-warfarin appear to be satisfactory and relatively simple methods of thromboembolic prophylaxis.  相似文献   
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