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91.
Abstract The structure of the secondary egg envelope of seven species of Cyprinodontidae belonging to the genus Epiplatys was observed by transmission and scanning electron microscopy. The transverse structure of the secondary envelope examined by transmission electron microscopy is a constant feature in all the species studied and represents a good criterion for identification. In contrast, the surface structure of the secondary envelope when observed by scanning electron microscopy exhibits a great diversity of form. It is possible to distinguish each of the seven different species by the pattern of ornamentation, the width of the polygons and the size of the granules comprising them on the secondary egg envelope.  相似文献   
92.
93.
BackgroundGestational Trophoblastic Disease comprises a group of benign and malignant disorders that derive from the placenta. Using Leventhal’s Common-Sense Model as a theoretical framework, this paper examines illness perception in women who have been diagnosed with this disease.MethodsThirty-one women diagnosed with Gestational Trophoblastic Disease in a hospital in Italy were asked to complete the Illness Perception Questionnaire-Revised to measure the following: illness Identity, illness opinions and causes of Gestational Trophoblastic Disease.ResultsHigh mean scores were observed in the Emotional representations and Treatment control subscales. A significant difference emerged between hydatidiform mole patients and those with gestational trophoblastic neoplasia on the Identity subscale. A significant correlation emerged between “time since diagnosis” and the Treatment control subscale.DiscussionThis study is the first to investigate illness perception in Gestational Trophoblastic Disease. From a clinical perspective the results highlight the need for multidisciplinary support programs to promote a more realistic illness perception.  相似文献   
94.
Summary A cDNA probe of 527 base pairs coding for the human platelet proteoglycan (PPG) protein core demonstrated that the PPG gene lies on the long arm of chromosome 10, band q22.1. This result and other available data concerning proteoglycans containing serine-glycine repeats indicate that this gene is involved in the expression of a proteoglycan in various blood cell types.  相似文献   
95.
The cDNA for TTF-1, a thyroid nuclear factor that binds to the promoter of thyroid specific genes, has been cloned. The protein encoded by the cDNA shows binding properties indistinguishable from those of TTF-1 present in nuclear extracts of differentiated rat thyroid cells. The DNA binding domain of TTF-1 is a novel mammalian homeodomain that shows considerable sequence homology to the Drosophila NK-2 homeodomain. TTF-1 mRNA and corresponding binding activity are detected in thyroid and lung. The chromosomal localization of the TTF-1 gene has been determined in humans and mice and corresponds to chromosomes 14 and 12, respectively, demonstrating that the TTF-1 gene is not located within previously described clusters of homeobox-containing genes.  相似文献   
96.
In a search for the non-muscle equivalent of calsequestrin (the low-affinity high-capacity Ca2(+)-binding protein responsible for Ca2+ storage within the terminal cisternae of the sarcoplasmic reticulum), acidic proteins were extracted from rat liver and brain microsomal preparations and purified by column chromatography. No calsequestrin was observed in these extracts, but the N-terminal amino acid sequence of the major Ca2(+)-binding protein of the liver microsomal fraction was determined and found to correspond to that of calreticulin. This protein was found to bind approx. 50 mol of Ca2+/mol of protein, with low affinity (average Kd approx. 1.0 mM). A monoclonal antibody, C6, raised against skeletal-muscle calsequestrin cross-reacted with calreticulin in SDS/PAGE immunoblots, but polyclonal antibodies reacted with native calreticulin only weakly, or not at all, after SDS denaturation. Immuno-gold decoration of liver ultrathin cryosections with affinity-purified antibodies against liver calreticulin revealed luminal labelling of vacuolar profiles indistinguishable from calciosomes, the subcellular structures previously identified by the use of anti-calsequestrin antibodies. We conclude that calreticulin is the Ca2(+)-binding protein segregated within the calciosome lumen, previously described as being calsequestrin-like. Because of its properties and intraluminal location, calreticulin might play a critical role in Ca2+ storage and release in non-muscle cells, similar to that played by calsequestrin in the muscle sarcoplasmic reticulum.  相似文献   
97.
98.
Summary A 2.3-kb-long probe derived from the 5 flanking region, the first exon and part of the first intron of the human muscle-specific phosphoglycerate mutase gene (PGAM-M) (EC 5.4.2.1) was used to map the gene by in situ chromosomal hybridization. The structural gene for PGAM-M was assigned to chromosome 7p12-7p13; a single hybridization peak indicated that there is a single gene for this isozyme of PGAM, and confirmed results obtained by Southern blot hybridization.  相似文献   
99.
The high incidence of chromosomal anomalies at birth and the severity of the resulting handicap led to examining their detectability by amniocentesis. With current indications for amniocentesis, the detection rate did not excede 30%. Consequently, it seems necessary to estimate the importance of other known risk factors and to calculate the resulting impact this would have on eventually broadening the indications for amniocentesis. A review of the literature led the authors to discuss the relative importance of each known risk factor and its role in public health.  相似文献   
100.
In 20 cases of Turner's syndrome (10 with complete X monosomy, 10 with partial X monosomy or mosaicism) aged 3.47 to 15.5 years, the stature of the individual cases and their parents were evaluated. A significant frequency of short stature in mothers (25% below--2.0 S.D.S) has been observed, with a significant difference compared to the mean female stature of the general population. No significant difference has been observed on the stature of fathers. There was a closer correlation with mother's height (r = 0.65, p = 0.001) than with father's height (p = 0.07).  相似文献   
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