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81.
Although the chromosome 18 alpha-satellite probe is considered to have a very low polymorphism rate, the routine use of this probe in prenatal diagnosis revealed rare variants in size and copy number of these sequences. A polymorphic signal was detected in preimplantation genetic diagnosis (PGD) for aneuploidy, in a patient with repeated early miscarriages. A third small signal of chromosome 18 alpha-satellite probe was observed in two of four evaluated embryos. Hybridization to the woman's metaphasic lymphocytes revealed that the small signal was localized in the pericentromeric region of chromosome 1. Reanalysis of blastomeres with telomeric probes for chromosome 18q confirmed the presence of only two copies of chromosome 18. Options for verifying PGD analysis results, to prevent misdiagnosis in cases of suspected polymorphism, are discussed. Although some authors speculate about a possible role of heterochromatin polymorphism in infertility, this rare polymorphism of 18 alpha-satellite sequences is in itself probably a normal variant. This is the third report of a cross-hybridization of the chromosome 18 alpha-satellite probe and the first report of the localization of the polymorphic 18 alpha-satellite signal to chromosome 1. 相似文献
82.
Smejkal K Chudík S Kloucek P Marek R Cvacka J Urbanová M Julínek O Kokoska L Slapetová T Holubová P Zima A Dvorská M 《Journal of natural products》2008,71(4):706-709
Eight C-6-geranylflavonoids ( 1- 8) were isolated from an ethanol extract of Paulownia tomentosa fruits. Tomentodiplacone ( 1), 3'- O-methyl-5'-hydroxydiplacone ( 2), 3'- O-methyl-5'- O-methyldiplacone ( 3), and tomentodiplacone B ( 4) were obtained as new compounds, and 3'- O-methyldiplacol ( 5) was isolated for the first time from a natural source. The structures of these new compounds were determined by using mass spectrometry (including HRMS) and 1D and 2D NMR spectroscopy, and the absolute configurations of the compounds were determined by circular dichroism. The antibacterial activities of 1- 8 against seven bacteria and yeast were evaluated. 相似文献
83.
de Faria DE Borges LV Peters VM Reis JE Ribeiro LC de Cássia da Silveira E Sá R Guerra Mde O 《Phytotherapy research : PTR》2008,22(2):185-189
The Gingko biloba extract is contraindicated during pregnancy and lactation due to the lack of information about its effects on these reproductive phases. Previous studies have shown that G. biloba extract contains components with estrogenic and antiestrogenic activities, thus nursing dams treated with the extract of this plant could show reduction in milk production, resulting in malnutrition and poor development of pups. This work analyzes the postnatal development of pups, whose mothers were treated with G. biloba extract during the lactation period. Nursing Wistar rats received 3.5 mg/kg/day of G. biloba aqueous extract, corresponding to the highest human dose. Clinical signs of maternal toxicity were evaluated. The growth rate, viability, survival during treatment and lactation indices of the pups were calculated. The physical, motor and sensorial development of the pups was also evaluated. No maternal signs of toxicity were observed. As there were no biological differences between control and G. biloba treated pups, it is possible to assume that, in this experimental design, the administration of G. biloba aqueous extract to nursing rats during the lactation period seems to be devoid of toxic effect to mothers and to the physical, motor and sensory development of the pups. 相似文献
84.
Durá JR 《Ginecología y obstetricia de México》2008,76(3):167-173
Progress in biostatistics and epidemiology during twentieth century contributed to clinical research development. Controversy about the real role of these disciplines in validating clinical activity isn't new: in history of medicine there are evidence since nineteenth century. Evidence-based medicine is a recent methodology to evaluate clinical investigation that begins to be considered gold standard in knowledge and medical practice evaluation. Its method is based mainly in systematized meta-analyses or revisions through which tries to offer answers to concrete clinical questions. These answers are, however, clearly of statistical nature. It is not useful in clinical practice but rather should be focused to teaching-learning process, as well as on the creation of work regulations. Its application implies certain benefits, but also several practical difficulties in cultural, academic and socio-economic fields, due to its use without discriminating. Thus, its correct use is a challenge to contemporary medicine. 相似文献
85.
Localization of porcine seminal plasma (PSP) proteins in the boar reproductive tract and spermatozoa
Spermadhesins are proteins containing a characteristic CUB domain, originally isolated from seminal plasma and ejaculated spermatozoa in domestic animals. Boar spermadhesins are multifunctional proteins exhibiting ligand-binding abilities with various endogenous ligands present in the male and female reproductive tracts and may play a role in the reproduction process. Porcine spermadhesins (AQN, AWN, PSP protein families) are secreted mainly by the seminal vesicles, but their mRNAs have been found also in the cauda epididymis and prostate. Unlike AQN and AWN spermadhesins, localization of porcine seminal plasma (PSP) proteins in the boar reproductive tract has not been completely resolved. This work has focused on PSP protein expression and localization in the boar reproductive organs and on spermatozoa. Using specific rabbit polyclonal antibodies (anti-PSP I and anti-PSP II), PSP I and PSP II proteins were immunodetected in tissue extracts and in secretory tissues of cauda epididymis, prostate, seminal vesicles and Cowper's glands on the blots and by an indirect immunofluorescence technique, respectively. Moreover, the ability of PSP proteins to bind to epididymal spermatozoa indicated their presence on cauda epididymal and ejaculated spermatozoa. Porcine seminal plasma proteins bind to the sperm surface at ejaculation and may modulate several aspects of sperm activity during reproduction. PSP proteins are produced not only by seminal vesicles and prostate, but also by epididymis. However, their prospective role in sperm epididymal maturation is not clear. Further characterization of seminal plasma protein forms expressed in the individual reproductive organs will help to understand their subsequent role in the reproduction process. 相似文献
86.
Melichar B Fridrichová P Lukesová S Mergancová J Urminská H Ryska A Foretová L 《European journal of gynaecological oncology》2008,29(2):188-190
The prognosis of patients with BRCA1-related breast carcinomas is inferior to the patients without BRCA1 mutation, but most of these tumors have a so-called triple negative phenotype characterized by increased chemosensitivity. Information regarding the chemosensitivity of BRCA1-related breast carcinomas is limited. We present a case of a mother and daughter with hereditary breast carcinoma treated with primary chemotherapy using the dose-dense combination of doxorubicin and cyclophosphamide and sequential weekly paclitaxel administration. Pathological complete response was observed in both patients. Subsequent genetic analysis revealed the same BRCA1 mutation with exon 5-14 deletion in both women. The present experience as well as other reports indicate increased sensitivity of BRCA1-related breast carcinoma to primary chemotherapy. 相似文献
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