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排序方式: 共有352条查询结果,搜索用时 140 毫秒
1.
A minority of 46,XX true hermaphrodites are positive for the Y-DNA sequence including SRY 总被引:4,自引:0,他引:4
Ken McElreavey Raphaël Rappaport Eric Vilain Nacer Abbas François Richaud Stéphen Lortat-Jacob Roland Berger Maryvonne LeConiat Chafika Boucekkine Kiran Kucheria Samia Temtamy Claire Nihoul-Fekete Raja Brauner Marc Fellous 《Human genetics》1992,90(1-2):121-125
Summary A total of 30 cases of 46,XX true hermaphroditism was analysed for Y-DNA sequences including the recently cloned gene for male testis-determination SRY. In 3 cases, a portion of the Y chromosome including SRY was present and, in 2 cases, was localised, to Xp22 by in situ hybridisation. Since previous studies have shown that the majority of XX males are generated by an X-Y chromosomal interchange, the Xp22 position of the Yp material suggests that certain cases of hermaphroditism can arise by the same meiotic event. The phenotype in the 3 SRY-positive cases may be caused by X-inactivation resulting in somatic mosaicism of testis-determining factor expression giving rise to both testicular and ovarian tissues. Autosomal or X-linked mutation(s) elsewhere in the sex-determining pathway may explain the phenotype observed in the remaining 27 SRY-negative cases. 相似文献
2.
The effects of extracellular matrix (ECM) proteins on the attachment of Pneumocystis carinii to lung cell lines in vitro. 总被引:2,自引:0,他引:2
Pneumocystis carinii cells labeled with fluorescein isothiocyanate were co-cultured with tissue culture cells. Measurements of attachment was determined by the tissue culture cell fluorescence after washing out the P. carinii organisms. The effects of the extracellular matrix proteins, laminin and fibronectin, on the binding of P. carinii onto the monolayer of cultured cells were investigated for better understanding of organism-cell interactions. The internalization of P. carinii by MRC5 cells was observed. 相似文献
3.
Alice Abd El-Aleem Ingolf Böhm Samia Temtamy Mostafa El-Awady Mohamed Awadalla Jörg Schmidtke Manfred Stuhrmann 《Human genetics》1995,96(5):577-584
Molecular genetic analysis of individuals from 6 Egyptian and 33 German families with fragile X syndrome and 240 further patients with mental retardation was performed applying a completely non-radioactive system. The aim of our study was the development of a non-radioactive detection method and its implementation in molecular diagnosis of the fragile X syndrome. Furthermore, we wanted to assess differences in the mutation sizes between Egyptian and German patients and between Egyptian and German carriers of a premutation. Using non-radioactive polymerase chain reaction (PCR), agarose gel electrophoresis and blotting of the PCR products, followed by hybridisation with a digoxigenin-labelled oligonucleotide probe (CGG)5 and chemiluminescent detection, we identified the fragile X full mutation (amplification of a CGG repeat in the FMR-1 gene ranging from several hundred to several thousand repeat units) in all patients. We observed no differences in the length of the CGG repeat between the Egyptian and German patients and carriers, respectively. However, in one prenatal diagnosis, we detected only one normal sized allele in a female fetus using the PCR-agarose assay, whereas Southern blot analysis with the digoxigenin labelled probe StB 12.3 revealed presence of a full mutation. Our newly established nonradioactive genomic blotting method is based on the conventional radioactive Southern blot analysis. Labelling of the probe StB 12.3 with digoxigenin via PCR allowed the detection of normal, premutated and fully mutated alleles. For exact sizing of small premutated or large normal alleles, we separated digoxigenin labelled PCR products through denaturing poly-acrylamide gelelectrophoresis (PAGE) and transfered them to a nylon membrane using a gel dryer. The blotted PCR-fragments can easily be detected with alkaline phosphate-labelled anti-digoxigenin antibody. The number of trinucleotide repeat units can be determined by scoring the detected bands against a digoxigenated M13 sequencing ladder. Our newly developed digoxigenin/chemiluminescence approach using PCR and Southern blot analysis provides reliable results for routine detection of full fragile X mutations and premutations. 相似文献
4.
The stability constants of the ternary Cu(II), Ni(II), and Co(II) complexes containing pyridoxamine (PM) and as a second ligand (L) glycine, DL-alanine, DL-valine, and β-phenylalnine were determined by pH-metric titration in 0.50 M KNO3 at 30°C. The corresponding constants of the equilibrium,
log X, are greater than would be expected for purely statistical reasons (log X = 0.6), except for few complex cases of Co(II). It has been also concluded that amino acids compete more than pyridoxamine for Ni(II) and Co(II) through the formation of 1:2:1:0 species rather than 2:1:1:0 of PM−:L−:M2+:H+. 相似文献
5.
Vanessa I. Rohlf Samia Toukhsati Grahame J. Coleman Pauleen C. Bennett 《Journal of applied animal welfare science : JAAWS》2013,16(3):213-236
Dog obesity is a common nutritional disorder affecting up to 40% of the companion animal (pet) dog population in Australia and other developed nations. A clear understanding of factors determining relevant caregiver (owner) behaviors underpins effective treatment for this disorder. The theory of planned behavior can be used to understand factors contributing to human behavior. This article describes research informed by this theory. The research examined relationships between owners' behavioral beliefs and barriers, normative beliefs and perceptions of control, owners' feeding and exercise behaviors toward their dogs, and the body condition scores (BCSs) of dogs. The study recruited a sample of 182 dog and owner dyads. The researcher independently assessed BCSs. Owners completed a questionnaire measuring relevant feeding and exercise beliefs and behaviors. This revealed significant correlations between many psychological variables and BCSs and between psychological variables and specific owner behaviors: for example, the relationship of low levels of intentions to feed appropriately to ambivalent beliefs toward feeding appropriately and low perceived control. Careful consideration of the specific variables identified will permit the development of more effective interventions. 相似文献
6.
Samia Aci Jean Ramstein Daniel Genest 《Journal of biomolecular structure & dynamics》2013,31(6):833-839
Abstract The thermodynamics of the opening/closure process of a GC base pair located at the stem-loop junction of the SL1 sequence from HIV-1Lai genomic RNA was investigated in the context of a loop-loop homodimer (or kissing complex) using molecular dynamics simulation. The free energy, enthalpy and entropy changes for the closing reaction are 0 kcal·mol?1, ?11 kcal·mol?1and ?0.037 kcal·mol?1-K?1 at 300° K respectively. Furthermore it is found that the free energy change is the same for the formation of a 11 nucleotide loop closed with UG and for the formation of a 9 nucleotide loop closed with GC. Our study evidences the high flexibility of the nucleotides at the stem-loop junction explaining the weak stability of this structure. 相似文献
7.
Sihem Dabbou Samia Dabbou Guido Flamini Gaetano Pandino Laura Gasco Ahmed Noureddine Helal 《化学与生物多样性》2016,13(11):1475-1483
The phytochemical composition in two Tunisian globe artichoke cultivars (bracts, leaves, and floral stems) was evaluated in the plant byproducts. The results indicated that the bracts contain the highest levels of total phenols, o‐diphenols, and flavonoids, whereas tannins seem to be more abundant in the leaves. Bracts from the ‘Violet d'Hyères’ cultivar possessed more total phenols (160.8 mg/g DW), flavonoids (64.9 mg/g DW), and anthocyanins (15.3 μg/g DW) than the ‘Blanc d'Oran’ bracts (134.5 mg/g DW, 51.2 mg/g DW, and 8.3 μg/g DW, resp.). Sixty‐four volatile compounds were identified in the headspace of globe artichoke material, particularly in the bracts. The volatile profile showed that sesquiterpene hydrocarbons and non‐terpene derivatives were the main volatiles emitted by the bracts in both cultivars. These results suggest that globe artichoke byproducts might represent a potential source of natural compounds, which could be used as nutraceuticals or as ingredients in the design of functional foods. 相似文献
8.
Hayfaa Wahabi Amel Fayed Samia Esmaeil Rasmieh Alzeidan Mamoun Elawad Rabeena Tabassum Shehnaz Hansoti Mohie Edein Magzoup Hanan Al-Kadri Elham Elsherif Hazim Al-Mandil Ghadeer Al-Shaikh Nasria Zakaria 《PloS one》2016,11(3)
Objectives
To assess the effects of non-communicable diseases, such as diabetes, hypertension and obesity, on the mother and the infant.Methods
A multicentre cohort study was conducted in three hospitals in the city of Riyadh in Saudi Arabia. All Saudi women and their babies who delivered in participating hospitals were eligible for recruitment. Data on socio-demographic characteristics in addition to the maternal and neonatal outcomes of pregnancy were collected. The cohort demographic profile was recorded and the prevalence of maternal conditions including gestational diabetes, pre-gestational diabetes, hypertensive disorders in pregnancy and obesity were estimated.Findings
The total number of women who delivered in participating hospitals during the study period was 16,012 of which 14,568 women participated in the study. The mean age of the participants was 29 ± 5.9 years and over 40% were university graduates. Most of the participants were housewives, 70% were high or middle income and 22% were exposed to secondhand smoke. Of the total cohort, 24% were married to a first cousin. More than 68% of the participants were either overweight or obese. The preterm delivery rate was 9%, while 1.5% of the deliveries were postdate. The stillbirth rate was 13/1000 live birth. The prevalence of gestational diabetes was 24% and that of pre-gestational diabetes was 4.3%. The preeclampsia prevalence was 1.1%. The labour induction rate was 15.5% and the cesarean section rate was 25%.Conclusion
Pregnant women in Saudi Arabia have a unique demographic profile. The prevalence of obesity and diabetes in pregnancy are among the highest in the world. 相似文献9.
Tasnim Ayadi Abdessalem Hammouda Samia Kididi Mohamed Habib Yahyaoui Slaheddine Selmi 《Ostrich》2016,87(2):173-177
Like the majority of Columbiformes, the Laughing Dove Spilopelia senegalensis is sexually monomorphic in plumage, but seems to be slightly dimorphic in size. However, due to the lack of studies little is known about the sexual size dimorphism in this species. In this work, we used morphometric data on a sample of 61 Laughing Doves from southern Tunisia, and sexed using a DNA-based method, to assess size differences between males and females and to determine a discriminant function useful for sex identification. The results showed that wing length was the most dimorphic trait, which could be due to the effects of sexual selection. The best function for the discrimination between sexes included wing length and head length, which is comparable with findings on other dove species. This discriminant function accurately classified 89% of birds, providing a rapid and accurate tool for sex identification in the studied population. Further data from different populations are needed for firmer conclusions about the extent of sexual size dimorphism and the reliability of the morphometric sexing approach in this dove species. 相似文献
10.
Samia E. Omer Tawasol M. Ibrahim Omer A. Krar Amna M. Ali Alaa A. Makki Walaa Ibraheem Abdulrahim A. Alzain 《Biochemistry and Biophysics Reports》2022
The current novel corona virus illness (COVID-19) is a developing viral disease that was discovered in 2019. There is currently no viable therapeutic strategy for this illness management. Because traditional medication development and discovery has lagged behind the threat of emerging and re-emerging illnesses like Ebola, MERS-CoV, and, more recently, SARS-CoV-2. Drug developers began to consider drug repurposing (or repositioning) as a viable option to the more traditional drug development method. The goal of drug repurposing is to uncover new uses for an approved or investigational medicine that aren't related to its original use. The main benefits of this strategy are that there is less developmental risk and that it takes less time because the safety and pharmacologic requirements are met. The main protease (Mpro) of corona viruses is one of the well-studied and appealing therapeutic targets. As a result, the current research examines the molecular docking of Mpro (PDB ID: 5R81) conjugated repurposed drugs. 12,432 approved drugs were collected from ChEMBL and drugbank libraries, and docked separately into the receptor grid created on 5R81, using the three phases of molecular docking including high throughput virtual screening (HTVS), standard precision (SP), and extra precision (XP). Based on docking scores and MM-GBSA binding free energy calculation, top three drugs (kanamycin, sulfinalol and carvedilol) were chosen for further analyses for molecular dynamic simulations. 相似文献