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121.
Summary A family with two independent reciprocal translocations t(3;19) and t(16;22) is described. The proband, a 4-week-old male, was phenotypically conspicious with multiple congenital anomalies. Cytogenetic examination revealed a balanced reciprocal translocation (3;19) and a supernumerary small marker chromosome. His mother carried two balanced reciprocal translocations, the one found in the proband and a reciprocal translocation (16;22). The maternal grandmother and a maternal uncle were identified as carriers of a single translocation (16;22). The findings in the family members permitted the identification of the proband's marker chromosome as a derivative chromosome 22 resulting in partial trisomy 16 and 22.  相似文献   
122.
123.
The structure of the retinal chromophore about the C = N and C14-C15 bonds in bacteriorhodopsin's M412 intermediate has been determined by analyzing resonance Raman spectra of 2H and 13C isotopic derivatives. Normal mode calculations on 13-cis-retinal Schiff bases demonstrate that the C15-D rock and N-CLys stretch are strongly coupled for C = N-syn chromophores and weakly coupled for C = N-anti chromophores. When the Schiff base geometry is anti, the C15-D rock appears as a localized resonance Raman active mode at approximately 980 cm-1, which is moderately sensitive to 13C substitution at positions 14 and 15 (approximately 7 cm-1) and insensitive to 13C substitution at the epsilon position of lysine. When the Schiff base geometry is syn, in-phase and out-of-phase combinations of the C15-D rock and N-CLys stretch are predicted at approximately 1060 and approximately 910 cm-1, respectively. The in-phase mode is more sensitive to 13C substitution at positions 14 and 15 (approximately 15 cm-1) and at the epsilon position of lysine (approximately 4 cm-1). Calculations and comparison with experimental data on dark-adapted bacteriorhodopsin indicate that the in-phase mode at approximately 1060 cm-1 carries the majority of the resonance Raman intensity. M412 exhibits a C15-D rock at 968 cm-1 that shifts 8 cm-1 when 13C is added at positions 14 and 15 and is insensitive to 13C substitution at the epsilon-position of lysine. This demonstrates that M412 contains a C = N-anti Schiff base.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
124.
To determine which sequences or structures in the poliovirus 5' noncoding region (5'NCR) are involved in binding proteins used for internal ribosome binding and protein synthesis initiation, translation competition assays were performed in rabbit reticulocyte lysates in the presence and absence of HeLa cell extract. The results revealed two functional domains in the poliovirus 5'NCR. One, requiring nucleotides (nts) 457 to 626, binds proteins that are required for translation of all mRNAs and that are present in both reticulocyte lysates and HeLa cell extracts. Another, contained within nts 286 to 456, interacts with proteins that are specific for poliovirus translation and are present in HeLa cells but not in significant amounts in rabbit reticulocyte lysates. In order to detect HeLa cell proteins that interact stably with the 5'NCR of poliovirus, UV cross-linking was used. At least four major protein-RNA complexes were identified, three of which were shown by RNA competition analysis to bind specifically to defined domains within the 5'NCR. Protein A (54 kDa) cross-linked to RNA sequences and/or structures located between nts 457 and 626; proteins B (48 kDa) and C (38 kDa) bound to nts 286 to 456.  相似文献   
125.
Thyroid hormone lowers serum cholesterol and alters sterol metabolic processes. This laboratory has previously reported increased biliary lipid secretion as an early effect of triiodothyronine (T3) in the rat. To evaluate whether the bile lipid action of T3 is a primary or secondary effect, the isolated-perfused rat liver model was used. Red blood cells in lipid-free buffer were used to perfuse livers of euthyroid and methimazole-hypothyroid rats, as well as hypothyroid rats given T3 at intervals before perfusion. Bile flow was maintained by taurocholate perfusion. Hypothyroid rats had elevated pre-perfusion serum cholesterol compared to euthyroid (107 +/- 4 vs. 65 +/- 2 mg/dl) and decreased biliary cholesterol (0.016 +/- 0.001 vs. 0.031 +/- 0.004 mumol/g liver/h) secretion. Serum cholesterol decreased to euthyroid levels by 18 h after T3, an effect that was prevented by bile duct ligation. Bile cholesterol secretion doubled by 18 h, and reached levels twice euthyroid by 42 h, while phospholipid secretion doubled to levels just above euthyroid. The fourfold increase in biliary cholesterol secretion occurred with lipid-free perfusion and unchanging bile acid uptake or output. It occurred without a fall in hepatic lipoprotein cholesterol secretion. Blockade of cholesterol synthesis with lovastatin failed to alter T3-augmented bile cholesterol secretion. We conclude that T3 induces biliary cholesterol secretion concomitantly with the fall in serum cholesterol. This augmented biliary secretion did not appear to depend upon lipoprotein uptake, increased bile acid transport, or cholesterol synthesis. It did not occur at the expense of hepatic lipoprotein secretion. Facilitated biliary lipid secretion may be a primary effect of T3.  相似文献   
126.
Summary Phenotypes of the erythrocyte enzymes phosphoglucomutase (PGM) (n-587), adenylate kinase (AK) (n=695), and adenosine deaminase (ADA) (n=616) were determined by horizontal starch gel electrophoresis in Thai subjects from norther Thailand, mainly from the provinces of Chiang Mai and Lamphun. The following gene frequencies were calculated: PGM 1 1 0.7385 PGM 1 2 0.2487 PGM 1 6 0.0102 PGM 1 7 0.0026, AK 1 0.9950 AK 2 0.0050, ADA 1 0.9180 ADA 2 0.0820.The regular, apparently autosomal transmission of the PGM 1 6 and PGM 1 7 alleles was demonstrated in 7 families revealing sufficient data.
Zusammenfassung Die Phänotypen der Erythrocytenenzyme Phosphoglucomutase (PGM) (n=587), Adenylatkinase (AK) (n=695), and Adenosindeaminase (ADA) (n=616) wurden mittles horizontaler Stärkegelelektrophorese bei Thailändern aus Nordthailand, hauptsächlich aus den Provinzen Chiang Mai und Lamphun, bestimmt. Auf Grund der Ergebnisse wurden die in der englischen Zusammenfassung angegebenen Genfrequenzen berechnet. Die regelmäßige, anschinend autosomale Vererbung der Allele PGM 1 6 und PGM 1 7 wurde in 7 Familien mit ausreichenden Daten nachgewiesen.


Established and supported by Stiftung Volkswagenwerk.  相似文献   
127.
Summary The concentration of serum-uric-acid (S.U.A.) was determined by a colorimetric method in 1010 male subjects from northern Thailand (710 recruits, 300 prisoners). S.U.A. levels were compared with several constitutional and genetic factors. Body-weight, glucose-6-phosphate dehydrogenase deficiency and haemoglobin E do not seem to influence S.U.A. concentration in this population. Blood-group A and low S.U.A. levels were associated in recruits and prisoners under 25 years, but not in those over 25 years old. There was a strong association between low S.U.A. concentration and the presence of a thalassaemia gene ( or variety) or increased osmotic resistance of the erythrocytes. This is probably an expression of the known positive correlation between the concentrations of S.U.A. and circulating haemoglobin.
Zusammenfassung Die Konzentration der Harnsäure im Serum (S.U.A.) wurde bei 1010 Männern aus Nord-Thailand (710 Rekruten; 300 Strafgefangenen) mit Hilfe einer kolorimetrischen Methode bestimmt. Die S.U.A.-Werte wurden mit verschiedenen konstitutionellen und genetischen Parametern verglichen. Körpergewicht, Glucose-6-Phosphat-Dehydrogenasemangel und Hämoglobin E scheinen in dieser Bevölkerung den S.U.A.-Wert nicht zu beeinflussen. Dagegen zeigte sich bei Rekruten und Strafgefangenen unter 25 Jahren eine Beziehung zwischen niedrigem S.U.A.-Wert und Blutgruppe A. Bei Personen über 25 fand sich diese Beziehung nicht. Außerdem fand sich eine engere Beziehung zwischen niedriger S.U.A.-Konzentration und der Anwesenheit eines Thalassämie-Gens (- oder -Typ) oder osmotischer Resistenz der Erythrocyten. Das ist wahrscheinlich, eine Folge der bekannten positiven Korrelation zwischen S.U.A.-Konzentration und zirkulierendem Hämoglobin.


Established and supported by Stiftung Volkswagenwerk, Hannover, Germany.  相似文献   
128.
Summary The C3 phenotype distribution was studied in 4 different populations from Afghanistan. The gene frequencies of C3s allele were: Tajiks (0.8547), Pushtoons (0.8812), Hazaras (0.9036) and Osbeks (0.8530). These values were significantly higher than in European populations studied previously. No significant differences were found between the mean serum levels of C3, C4 and C3-proactivator among 4 population groups. A higher concentration of IgG, IgA and IgM was observed in Afghanistan sera than reported for Europeans.Supported by the Stiftung Volkswagenwerk.Dedicated to Prof. J. Kühnau on his 75th birthday.  相似文献   
129.
Summary Single intransal applications of MTP-PE, a lipophilic muramyl peptide, induce tumouricidal and tumouristatic leucocytes in the lungs of rats. In ex vivo assays the tumouristatic activity was detectable for 8 days after drug administration. By separation of the effector cells on Ficoll-Hypaque gradients, it was shown that both neutrophils and macrophages are responsible for this activity. Using the B16/BL6 melanoma system in mice, there was a high survival rate after repeated intranasal applications of MTP-PE  相似文献   
130.
Here is reported the development of an experimental model using intravital microscopy as a tool to orthotopically investigate malignant bone tumours. Although up to 85% of the most frequently occurring malignant solid tumours, such as lung and prostate carcinomas, metastasize into the bone, and despite the knowledge that a tumour's course may be altered by its surrounding tissue, there is no adequate experimental model available enabling the investigation of orthotopically grown bone tumours in vivo. Intravital microscopy is an internationally accepted experimental method, used in various acute and chronic animal models, that enables qualitative and quantitative analysis of the angiogenesis, microcirculation, growth behaviour, etc. of various benign and malignant tissues. Non-invasive investigations of up to several weeks are possible. Additionally, tissue samples can be taken after termination of the in vivo experiments for further ex vivo investigation (histology, immunohistochemistry, molecular biology, etc.), elucidating the mechanisms that underlie the in vivo observations. Severe combined immunodeficient mice were fitted with a cranial window preparation where the calvaria served as the site for orthotopic implantation of the solid human tumours Saos-2 osteosarcoma (primary) and A 549 lung carcinoma and PC-3 prostate carcinoma (secondary). In all preparations, the take rate was 100%. Histological assessment confirmed the data obtained in vivo, showing typical tumour growth with infiltration of the surrounding osseous and soft tissues. This novel model serves as a valuable tool in understanding the biology of primary and secondary bone tumours in physiological and pathophysiological situations, with implications for the most areas of tumour therapy such as chemotherapy, radiation and antiangiogenesis.  相似文献   
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