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31.
32.
High risk pregnancies in hypopituitary women   总被引:1,自引:0,他引:1  
BACKGROUND: Various short papers have suggested that pregnancies in women with hypopituitarism are high risk but no formal assessment of pregnancy outcome has yet been reported. METHODS: An audit was carried out concerning the outcome of 18 pregnancies in nine women who underwent ovulation induction in a single centre over 20 years. RESULTS: The live birth rate was 61%, miscarriage rate 28% and mid-trimester uterine death rate 11% with no survivors from four sets of twins. The Caesarian section rate was 100% and half of the live births were on or below the 10th centile for weight. One woman successfully breast-fed. CONCLUSIONS: Women with hypopituitarism have high-risk pregnancies, perhaps because of a uterine defect secondary to endocrine deficiency. Fertility treatment must strive for singleton pregnancies with application of particularly strict criteria to avoid twin pregnancies. Early elective Caesarian section is probably warranted in this group.  相似文献   
33.
A murine TSPY     
Sequences homologous to human and bovine TSPY were isolated from M. musculus testicular cDNA, and a nearly full-length gene was polymerase chain reaction (PCR) amplified from mouse genomic DNA. This gene is apparently non-functional. Contrary to the situation encountered in species along the primate and artiodactyl lineages, in which TSPY is moderately repetitive, murine Tspy appears to be single copy. Murine Tspy is located on Yp, i.e. in the same syntenic group as in man. Sequence comparisons of murine, human and bovine TSPY exons suggest that TSPY became non-functional during rodent evolution.  相似文献   
34.
35.
Summary: Sarcosine‐N‐carboxyanhydride (Sar‐NCA), L ‐alanine‐NCA and D,L ‐alanine‐NCA were polymerized with benzylamine as initiator in three different solvents: dichloromethane (CH2Cl2), 1,4‐dioxane and dimethylformamide (DMF). The isolated polyaminoacids were characterized by 1H NMR spectroscopy and MALDI‐TOF mass spectrometry. High conversions and degrees of polymerization s close to the monomer‐initiator (M/I) ratios were found for all polypeptides. For polysarcosine which was soluble under the given reaction conditions a narrow monomodal frequency distribution was found. In contrast, a broad frequency distribution was observed, when L ‐alanine NCA was polymerized in dioxane and DMF. These results were attributed to a partial precipitation of oligopeptides in the β‐sheet structure, which reduces the reactivity of endgroups for steric reasons. The polymerizations of D,L ‐alanine‐NCA showed features in between the extremes of Sar‐NCA and L ‐Ala‐NCA.

Schematic illustration of the secondary structures formed in a primary amine initiated polymerization of L ‐Ala‐NCA.  相似文献   

36.
BACKGROUND: The [PSI+] element of the budding yeast is an aggregated form of the translation release factor Sup35 that is propagated and transmitted cytoplasmically in a manner analogous to that of mammalian prions. The N-terminal of Sup35, necessary for [PSI+], contains oligopeptide repeats and multiple Gln/Asn residues. RESULTS: We replaced the Gln/Asn-rich prion repeats of Sup35 with non-Gln/Asn repeats from heterologous yeast strains. These non-Gln/Asn repeat Sup35s propagated a novel [PSI+] variant, [PHI+], that appeared de novo 103 times more frequent than [PSI+]. [PHI+] was stably inherited in a non-Mendelian fashion, but not eliminated upon the inactivation of Hsp104, unlike known [PSI+] elements. In vitro, non-Gln/Asn repeat domains formed amyloid fibres that were shorter and grew more slowly than did Gln/Asn-rich prion domains, while [PHI+] aggregates were smaller than [PSI+] aggregates in vivo. CONCLUSIONS: These findings suggest the existence of an alternative, Hsp104-independent pathway to replicate non-Gln/Asn variant Sup35 prion seeds.  相似文献   
37.
Production of Specific Antisera to Human B Lymphocytes   总被引:4,自引:0,他引:4  
Antisera have been prepared, in mice and rabbits, to membrane and sub-membrane fractions of human B lymphocyte derived lymphoid lines. Antisera to a protein subfraction were, after only minimal absorption, specific for human peripheral B lymphocytes, monocytes and B cell derived lymphoid lines. The antigen(s) recognised by these antisera were not the same as the previously described B-cell markers; immunoglobulin, Fc receptor, complement receptor and Ia antigens. The antigen(s) could not be removed from cells by lysostrip with anti- β2 microglobulin.  相似文献   
38.
39.
Sun exposure in childhood is 1 of the risk factors for developing skin cancer, yet little is known about levels of exposure at this age. This is particularly important in countries with high levels of ultraviolet radiation (UVR) such as Australia. Among 49 children 3 to 5 years of age attending child care centers, UVR exposure was studied under 4 conditions in a repeated measures design; sunny days, cloudy days, teacher’s instruction to stay in the shade, and a health professionals instruction to apply sunscreen. Three different data collection methods were employed: (a) completion of questionnaire or diary by parents and researcher, (b) polysulphone dosimeter readings, and (c) observational audits (video recording). Results of this study indicated that more than half the children had been sunburnt (pink or red) and more than a third had experienced painful sunburn (sore or tender) in the last summer. Most wore short sleeve shirts, short skirts or shorts and cap, that do not provide optimal levels of skin protection. However, sunscreen was applied to all exposed parts before the children went out to the playground. Over the period of 1 hr (9–10 a.m.) the average amount of time children spent in full sun was 22 min. On sunny days there was more variation across children in the amount of sun exposure received. While the potential amount of UVR exposure for young children during the hour they were outside on a sunny day was 1.45 MED (Minimum Erythemal Dose), they received on average 0.35 MED, which is an insufficient amount to result in an erythemal response on fair skin even without the use of sunscreen.  相似文献   
40.
We purified to near homogeneity a previously identified 100 kDa mammalian homologous DNA pairing protein. The purified 100 kDa protein also catalyzed high levels of cell-free homologous DNA recombination activity. This ATP-dependent activity was capable of forming conservative recombinant products between two circular, double-stranded DNA molecules. We were unable to detect any DNA polymerase, DNA ligase, or 5' or 3' exonuclease activity associated with this purified material. The purified 100 kDa protein bound silver nitrate as well as a monoclonal antibody specific for nucleolin. A recombinant protein comprised of the Escherichia coli maltos-ebinding protein fused to the carboxyl-terminal two-thirds of human nucleolin possessed homologous DNA pairing activity. These data indicate that the 100 kDa homologous DNA pairing protein is nucleolin. The observation that nucleolin can carry out homologous DNA strand pairing in vitro raises the prospect that it may function similarly in vivo.  相似文献   
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