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991.
Purified murein from Thiobacillus neapolitanus was poorly digested by lysozyme. It's sensitivity to the enzyme greatly increased after N-acetylation. The murein was found to contain 30 to 35% glucosamine residues lacking N-acetyl groups. It also contained phosphomuramic acid. Further modifications included amidation of diaminopimelic acid in the peptide side chains and a low alanine content. None of these modifications were found in the murein of another sulphur bacterium, Thiobacillus versutus.  相似文献   
992.
OBJECTIVE--To determine the course of maternally derived elevations in thyrotropin-binding inhibitory immunoglobulins in a neonate. DESIGN--Case report. SETTING--University pediatric endocrinology clinic and endocrine immunology laboratory in Ohio. PARTICIPANTS--An infant with elevated thyrotropin levels but near-normal total thyroxine levels, and her mother. INTERVENTIONS--None. MEASUREMENTS/MAIN RESULTS--Thyroid hormone, thyrotropin, and thyrotropin-blocking immunoglobulin concentrations were serially measured in a woman and her infant, who was found to have elevated thyrotropin levels (234 mU/L) and borderline low thyroxine levels (95 nmol/L). As infant thyroxine concentrations remained normal (125 to 145 nmol/L), no thyroxine supplementation was given. Thyrotropin levels decreased concomitantly with thyrotropin-blocking inhibitory immunoglobulin levels, and normalized by day 56 of life. The apparent elimination half-life of thyrotropin-blocking immunoglobulins was 7.5 days. CONCLUSIONS--The observed parallel elimination kinetics suggest that the thyrotropin receptor antibody acts as a thyrotropin antagonist, resulting in compensatory thyrotropin elevations. The duration of such elevations may be predicted on the basis of such elimination.  相似文献   
993.
994.
Management of infertility is slow, time consuming and, paradoxically, costly. It needs to be streamlined so that diagnosis and management go hand in hand with proper division between primary physicians at district level and highly trained specialists at regional level. Incorporation of assisted conception techniques is the key to the success of such an approach.  相似文献   
995.
In 1984 a late malaria endemic area, called Bodrogk?z was studied. This was a reexamination of the population genetic work performed by Walter, Nemeskéri. In six villages of Bodrogk?z 328 persons were tested for AB0, Rh blood groups, haptoglobins, haemoglobin concentration, haematocrit, erythrocyte amount, the MCV, the MCH and the G-6-PD were analyzed. The quantitative determination of HbF and HbA2, red cell osmotic resistance and thalassemia were measured as well. Thalassemia heterozygote carriers and an increased level of HbF were revealed. The frequency of G-6-PD deficiency was 0.39%. In Bodrogk?z the frequencies of AB0, Rh and haptoglobin types were similar in the present and all previous studies. The background of this similarity might be the genetic similarity between two following generations. On the basis of these facts, the Hb0 Arab and partially DNA work we suggested an alternative hypothesis that these mutant genes got into Bodrogk?z by the rather later migration than with ancient Hungarian people during the period of conquest of Hungary.  相似文献   
996.
997.
J Bódis  I Csaba  E Gács 《Orvosi hetilap》1992,133(1):47-48
The authors described a 7 weeks old cervical pregnant case, whome was administered 250 mg methotrexate in infusion to eliminate the throphoblastic tissue. 3 days later the HCG was negative in the urine. After the dilatation of cervix by laminaria, the collapsed amniotic sac came from the cervix with minimal hemorrhage. They suggest the method is suitable to prevent the serious complications of cervical pregnancy.  相似文献   
998.
HIV-1 infectivity of human carcinoma cell lines lacking CD4 receptors.   总被引:2,自引:0,他引:2  
Human immunodeficiency virus type 1 (HIV-1) prototype, HIV1 LAV, and a Zairian virus HIV1 NDK, an isolate highly cytopathic for CD4+ lymphocytes, were used to infect eleven different CD4 negative non-lymphoid human cell lines. Eight of the lines were derived from carcinomas wherein human papillomavirus was thought to have been etiologic. All these cell lines lacked CD4 receptor and CD4 specific mRNA. After cocultivation with sensitive CEM cells, HIV-1 LAV was rescued from six infected cell lines and HIV-1 NDK from nine. Shedding of free virus into the culture medium was observed in three cell lines infected by HIV-1 NDK and in only one cell line infected by HIV-1 LAV. The infectibility of CD4 negative cell lines indicates that both HIV-1 strains were able to use a CD4 independent mechanism to infect the cells; however, HIV-1 NDK showed the higher efficiency of infection. This virus was also able to overcome the intracellular block of viral reproduction. These results suggest that a broader spectrum of cell types of non-lymphoid origin lacking the CD4 receptor can serve as a viral reservoir. In some cases they are direct producers of infectious HIV-1 particles. This suggests, that in addition to immunosuppressive mechanisms, HIV-1 could play a more direct role in induction of neoplastic changes.  相似文献   
999.
The relationship between dietary fat intake and fasting plasma lipid levels was assessed in 35 female and 19 male adolescents recruited from two local education authority schools in Norwich, UK. Dietary intakes were assessed using a 7-day weighed dietary record method, coupled with the collection of duplicate diets. Fat and energy intakes calculated using food composition tables were compared with values obtained by direct analysis of duplicate diets. Fasting plasma lipid levels (total, HDL and LDL cholesterol and triglycerides) were measured and compared with total dietary lipids and fatty acid intakes. The average proportion of energy consumed as fat was higher than is currently considered desirable but lower than previous studies have reported for adults. Mean serum total cholesterol values were 4.2 (SEM 0.1) mmol for females and 4.5 (SEM 0.2) mmol for males; this difference was not statistically significant. In male subjects the dietary fatty acid profiles were significantly correlated with several parameters of plasma lipid status which are thought to be risk factors for coronary heart disease, and in particular with the ratio of total:HDL cholesterol.  相似文献   
1000.
Translated from Khimiko-farmatsevticheskii Zhurnal, Vol. 26, No. 5, pp. 43–45, May, 1992.  相似文献   
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