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81.
Transforming growth factor (TGF) is known to have the abilityto modify mitogenic responses of tissues to other peptide growthfactors and therefore may contribute to the rapid growth rateof an embryo. Throughout the TGF superfamily there is a similarfundamental molecular architecture. Included in this superfamilyare inhibin A, activin A and activin B. It has been shown thatactivin is a powerful mesodermal inducing factor in the earlyembryo. The human embryo has shown localization of inhibin inthe gonads after 16 weeks gestation but it has not been previouslyidentified in earlier embryos. The inhibin-activin protein wasfound in a range of tissues including the liver stages 19-21() and stages 19-22 (ß); oesophagus stages 19-22 (and ß); stomach stages 21 and 22 ( and ß);gut stages 16-22 () and 21 and 22 (ß); pericardiumstages 12-22 ( and ß); gonad stages 21 and 22 (ß)stage 22 (); adrenal stages 19-22 ( and ß); urogenitalsystem states 21 and 22 ( and ß); yolk sac stage 12( and ß); mesenchyme stages 16-22 (); surface ectodermstages 13-22 () and stages 16-22 (ßa); notochord stages13-22 (ß) and stages 21 and 22 (); nasal, tracheaand bronchi stages 19-22 ( and ß) leading to speculationof the role of both subunits. 相似文献
82.
Localization of the mRNA and ßa subunits of inhibinhas previously been reported in the human gonads during thesecond trimester. Adrenal inhibin has also been reported inthe second trimester for the ßa and ßbsubunits. Investigations showing localization by in-situ hybridizationduring the first trimester have not been reported. The resultshave shown hybridization of the and ßa subunits,throughout the period of development studied, in a variety oftissues including the dorsal and thoracic aortas and pericardiumstages 13-22 (ßa subunit); liver stages 19-21 (ßa)and stages 21-22 (); mesonephros stages 21 and 22 (ßa);gonad stages ( and ßa); adrenal stages 19-22 (); surfaceectoderm stages 16-22 (ßa); mesenchyme stages 16-22(ßa); amnion stages 13-16 (ßa); yolk sacstage 12 ( and ßa); cartilage stages 19-22 (ßa);and nasal proliferation stages 21 and 22 (ßa). Whencompared with distribution of the protein subunits it was notedthat more immunostaining activity was found, suggesting thatprobes were not sufficiently sensitive enough to detect alllevels of mRNA expressed. It can be surmised, therefore, thatthe lack of visual hybridization of the mRNA cannot precludethe possibility that it is not being translated within the tissueeven though hybridization was not apparent. 相似文献
83.
Progesterone receptor subtype B is differentially regulated in human endometrial stroma 总被引:9,自引:4,他引:9
Two anti-progesterone receptor (PgR) antibodies, a new one specific to
PgRB, the other to PgR subtypes A + B, have been used to examine the
cellular location of PgR subtypes A and B in normal endometrium throughout
the menstrual cycle and in early human decidua by standard
immunohistochemical techniques. PgR(A+B) is the receptor detected by the
antibody recognizing both isoforms of the receptor. PgRB is the receptor
detected by the new antibody specific to the B isoform. Since it is not
possible to raise antibody specific to PgR subtype A, all
immunohistochemical analysis of the PgRA subtype is by subtractive
inference. Thus we refer to PgRA as the subtype responsible for positive
immunoreactivity when the PgRB subtype cannot be specifically detected.
Endometrial biopsies were collected from 40 women with regular menses (n =
5 each stage of cycle: menstrual; early, mid and late proliferative;
ovulatory; early, mid, and late secretory). Decidual tissue was obtained
from 10 women undergoing first trimester surgical termination of pregnancy.
As previously reported, the PgR(A+B) antibody stained glandular and stromal
nuclei during the proliferative phase but only stromal nuclei during the
secretory phase and early pregnancy. The new PgRB antibody also stained
both cell types intensely during the proliferative phase, but failed to
stain either stromal or glandular nuclei strongly during the secretory
phase and early pregnancy. We concluded that, while both PgR subtypes were
present in glands and stroma in the proliferative phase, and both subtypes
were dramatically reduced in the glands during the secretory phase, PgRA
remained as the predominant type in the stroma during the secretory phase
and early pregnancy. The profound effects of progesterone on endometrium
during the secretory phase and early pregnancy appear to be mediated
primarily by PgRA in the stroma.
相似文献
84.
Brown KA; Janjua AH; Karbani G; Parry G; Noble A; Crockford G; Bishop DT; Newton VE; Markham AF; Mueller RF 《Human molecular genetics》1996,5(1):169-173
Autosomal recessive non-syndromal hearing impairment (NSRD) is genetically
heterogeneous. Five loci have been identified to date which map to
chromosomes 13 (DFNB1), 11 (DFNB2), 17 (DFNB3), 7 (DFNB4) and 14 (DFBN5).
We report definite linkage of NSRD to the locus DFNB1 in a single family of
27 families studied of Pakistani origin. Haplotype analysis of markers in
the pericentromeric region of chromosome 13q revealed a recombination event
which maps DFNB1 proximal to the marker D13S175 and in the vicinity of
D13S143.
相似文献
85.
86.
DT Mage 《Environmental health perspectives》2001,109(12):A570-A571
87.
Ngo T Hoa Tran TB Chieu Ho DT Nghia Nguyen TH Mai Pham H Anh Marcel Wolbers Stephen Baker James I Campbell Nguyen VV Chau Tran T Hien Jeremy Farrar Constance Schultsz 《BMC infectious diseases》2011,11(1):1-8
Background
Our objective was to determine the frequency and determinants of presentation to care with advanced HIV disease in patients who discover their HIV diagnosis at this stage as well as those with delayed presentation to care after HIV diagnosis in earlier stages.Methods
We collected data on 1,819 HIV-infected patients in Brussels (Belgium) and Northern France from January 1997 to December 2007. "Advanced HIV disease" was defined as CD4 count <200/mm3 or clinically-defined AIDS at study inclusion and was stratified into two groups: (a) late testing, defined as presentation to care with advanced HIV disease and HIV diagnosis ≤6 months before initiation of HIV care; and (b) delayed presentation to care, defined as presentation to care with advanced HIV disease and HIV diagnosis >6 months before initiation of HIV care. We used multinomial logistic regression to determine the factors associated with delayed presentation to care and late testing.Results
Of the 570 patients initiating care with advanced HIV disease, 475 (83.3%) were tested late and 95 (16.7%) had delayed presentation to care. Risk factors for delayed presentation to care were: age 30-50 years, injection drug use, and follow-up in Brussels. Risk factors for late testing were: sub-Saharan African origin, male gender, and older age. HIV transmission through heterosexual contact was associated with an increased risk of both delayed presentation to care and late testing. Patients who initiated HIV care in 2003-2007 were less likely to have been tested late or to have a delayed presentation to care than patients who initiated care before 2003.Conclusion
A considerable proportion of HIV-infected patients present to care with advanced HIV disease. Late testing, rather than a delay in initiating care after earlier HIV testing, is the main determinant of presentation to care with advanced HIV disease. The factors associated with delay presentation to care differ from those associated with late testing. Different strategies should be developed to optimize early access to care in these two groups. 相似文献88.
I Ikonomidis M Nikolaou I Paraskevaidis J Lekakis DT Kremastinos 《European journal of echocardiography》2008,9(1):133-135
A 59-year-old woman was admitted in our hospital due to persistentcough and dyspnea. Transthoracic 2-dimensional echocardiographydemonstrated a cardiac mass (29x34 mm) that extended from theright upper pulmonary vein into the left atrium causing thepartial obstruction of the right lower vein as indicated bythe increased Doppler velocities. Contrast echocardiographyconfirmed the presence of microcirculation within the mass.During transesophageal (TEE) echocardiographic study, colorDoppler imaging and power Doppler imaging (Angio® Vivid7, GE Medical System, Horten, Norway) demonstrated the presenceof vascular flow within the mass. A chest magnetic resonancetomography showed a pulmonary mass of 30x25x28 mm infiltratingthe pulmonary veins. After surgery, biopsy confirmed a highgrade mucoepidermoid lung cancer with few large arterioles.The new echocardiographic techniques can reliably differentiatea cardiac tumor from a cardiac thrombus. 相似文献
89.
Evidence for a novel gene for familial febrile convulsions, FEB2, linked to chromosome 19p in an extended family from the Midwest 总被引:8,自引:0,他引:8
Johnson EW; Dubovsky J; Rich SS; O'Donovan CA; Orr HT; Anderson VE; Gil-Nagel A; Ahmann P; Dokken CG; Schneider DT; Weber JL 《Human molecular genetics》1998,7(1):63-67
Febrile convulsions are a common form of childhood seizure. It is estimated
that between 2 and 5% of children will have a febrile convulsion before the
age of 5. It has long been recognized that there is a significant genetic
component for susceptibility to this type of seizure. Wallace, Berkovic and
co-workers recently reported linkage of a putative autosomal dominant
febrile convulsion gene to chromosome 8q13-21. We report here another
autosomal dominant febrile convulsion locus on chromosome 19p. Linkage
analysis in this large multi- generational family gave a maximum pairwise
lod score of 4.52 with marker Mfd120 at locus D19S177. Linkage to the
chromosome 8 locus was excluded in this family. Haplotype analysis using
both affected and unaffected family members indicates that this febrile
convulsion gene, which we call FEB2 , can be localized to an 11.7 cM, 1-2
Mb section of chromosome 19p13.3, between loci D19S591 and D19S395.
相似文献
90.