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991.
992.
Uterine myomata and outcome of assisted reproduction 总被引:5,自引:8,他引:5
Ramzy AM; Sattar M; Amin Y; Mansour RT; Serour GI; Aboulghar MA 《Human reproduction (Oxford, England)》1998,13(1):198-202
The aim of this work was to study the effect of uterine myomata on the
implantation rate and outcome in in-vitro fertilization (IVF) and
intracytoplasmic sperm injection (ICSI). Among 406 patients, 51 (12.6%)
were found to have uterine corporeal myomata. Twelve patients were excluded
from the study as they had large myomata, submucous myomata or intramural
myomata encroaching on the cavity. These patients were advised to have
myomectomy before being enrolled in the IVF/ICSI programme. The remaining
patients (n = 39) were sorted according to the number, site and size of the
myomata as assessed by transvaginal sonography. Three patients had more
than one myoma. Most of the myomata were subserous (72.7%) and the mean
diameter of the myomata was 3.5 +/- 0.9 cm. A control group (n = 367) was
chosen with normal uteri and no history of uterine reconstruction surgery.
The mean age of myoma patients was 34.7 +/- 3.6 years as compared to 34.0
+/- 4.4 years in the control group. The age, period of infertility, body
mass index, duration and number of human menopausal gonadotrophin ampoules
needed for stimulation, oestradiol levels, number of oocytes retrieved and
the fertilization rate were not significantly different in the myoma
patients compared to the control group. Fifteen myoma patients (38.5%)
subsequently showed one or more pregnancy sacs on ultrasonography of which
three (20%) spontaneously aborted during the first trimester and two
(13.3%) had preterm labour, as compared to 123 (33.5%), 19 (15.5%) and nine
(7.3%) respectively, among the control group (P = 0.27, 0.33 and 0.21). In
conclusion, uterine corporeal myomata, not encroaching on the cavity and
<7 cm in mean diameter, do not affect the implantation or miscarriage
rates in IVF or ICSI.
相似文献
993.
994.
Distribution of mutations in the PEX gene in families with X-linked hypophosphataemic rickets (HYP) 总被引:8,自引:0,他引:8
Rowe PS; Oudet CL; Francis F; Sinding C; Pannetier S; Econs MJ; Strom TM; Meitinger T; Garabedian M; David A; Macher MA; Questiaux E; Popowska E; Pronicka E; Read AP; Mokrzycki A; Glorieux FH; Drezner MK; Hanauer A; Lehrach H; Goulding JN; O'Riordan JL 《Human molecular genetics》1997,6(4):539-549
Mutations in the PEX gene at Xp22.1 (phosphate-regulating gene with
homologies to endopeptidases, on the X-chromosome), are responsible for
X-linked hypophosphataemic rickets (HYP). Homology of PEX to the M13 family
of Zn2+ metallopeptidases which include neprilysin (NEP) as prototype, has
raised important questions regarding PEX function at the molecular level.
The aim of this study was to analyse 99 HYP families for PEX gene
mutations, and to correlate predicted changes in the protein structure with
Zn2+ metallopeptidase gene function. Primers flanking 22 characterised
exons were used to amplify DNA by PCR, and SSCP was then used to screen for
mutations. Deletions, insertions, nonsense mutations, stop codons and
splice mutations occurred in 83% of families screened for in all 22 exons,
and 51% of a separate set of families screened in 17 PEX gene exons.
Missense mutations in four regions of the gene were informative regarding
function, with one mutation in the Zn2+-binding site predicted to alter
substrate enzyme interaction and catalysis. Computer analysis of the
remaining mutations predicted changes in secondary structure,
N-glycosylation, protein phosphorylation and catalytic site molecular
structure. The wide range of mutations that align with regions required for
protease activity in NEP suggests that PEX also functions as a protease,
and may act by processing factor(s) involved in bone mineral metabolism.
相似文献
995.
Induction of B cell apoptosis by co-cross-linking CD23 and sIg involves aberrant regulation of c-myc and is inhibited by bcl-2 总被引:2,自引:0,他引:2
Campbell KA; Studer EJ; Kilmon MA; Lees A; Finkelman F; Conrad DH 《International immunology》1997,9(8):1131-1140
A novel system to study the effects of co-cross-linking CD23/FceRII and sIg
on murine B lymphocytes utilizes a highly multivalent form of anti- Ig
prepared by covalently linking anti-Ig antibodies to a DNP-dextran
backbone. CD23-sIg co-cross-linking is accomplished by the addition of
DNP-specific monoclonal IgE. Previous studies demonstrated that co-
cross-linking CD23 and sIg significantly inhibited mouse B cell
proliferation, especially at high doses of the multivalent anti-Ig.
Interestingly, examination of early activation signals reveals no
difference in B cells subjected to co-cross-linking conditions as compared
to B cells activated with anti-Ig alone. Total cellular protein tyrosine
phosphorylation levels are unchanged by co-cross- linking. Analysis of B
cell mRNA reveals that co-cross-linking the receptors does not alter the
expression levels of ornithine decarboxylase 8 h after stimulation as
compared to the controls. In contrast, levels of the proto-oncogene c-myc
were significantly elevated 1 h after inducing B cell activation under
co-cross-linking conditions. However, it remains unclear whether this
aberrant c-myc regulation plays any role in inducing apoptosis. In
addition, on day 3 after stimulation, the co-cross-linking of CD23 and sIg
resulted in the formation of apoptotic B cells, determined by both
photomicroscopy of the B cell cultures and FACS analysis of B cell nuclei.
B cells obtained from bcl-2 transgenic mice proliferated as well as
controls, and failed to undergo apoptosis when CD23 and sIg were
co-cross-linked on their surface. These studies indicate that
co-cross-linking of CD23 with B cell sIg inhibits B cell proliferation by a
mechanism that is distinct from that seen by co-cross-linking of the Fc
gamma RII and sIg. In addition, these results suggest a means by which
antigen- specific IgE can down-regulate additional B cell activation and
IgE synthesis.
相似文献
996.
P. Venditti M. C. Piro G. Artiaco S. Di Meo 《European journal of applied physiology》1996,74(4):322-329
We studied the changes in the anti-oxidant capacity of tissues, such as heart, liver, and blood in male and female rats, as a parameter for evaluating oxidative stress after either a prolonged (210 min) or an exhausting bout of swimming. Furthermore, we also investigated exercise-induced changes in the electrophysiological properties, measured in vitro, of papillary muscle fibres. Small decreases of anti-oxidant capacities after prolonged exercise [0.10 (SEM 0.04) in heart, 0.43 (SEM 0.19) in liver, 0.22 (SEM 0.05) in blood] and greater decreases after exhausting exercise [0.23 (SEM 0.04) in heart, 0.90 (SEM 0.29) in liver, 0.34 (SEM 0.04) in blood] were found in tissues from the male rats. For the female rats, similar changes were found only in the blood [0.11 (SEM 0.07) and 0.35 (SEM 0.06) for prolonged and exhausting exercise, respectively]. Liver and heart anti-oxidant capacity remained unchanged after prolonged exercise, while after exhausting swimming it underwent a decrease almost the same as found in the male rats, though the swimming time to exhaustion (endurance capacity) was much greater [706 (SEM 10) min and 444 (SEM 32) min for the females and males, respectively]. The duration of the action potential, recorded from papillary muscle fibres, underwent changes related to the decreases in heart anti-oxidant capacity. In fact, the action potential duration (APD) was shorter only in preparations from the male rats after prolonged exercise, but in all preparations after exhausting exercise. After such exercise, the APD was similar for the male and female rats [37.1 (SEM 3.4) ms and 37.0 (SEM 3.6) ms, respectively]. Such a pattern was independent of stimulation frequency, since it was found substantially unchanged when the frequency was increased from 1 to 5 Hz. We concluded that the different susceptibilities to the effects of physical exercise, exhibited by tissues from these male and female rats might have been related to different capacities to oppose oxidative stress effectively. 相似文献
997.
Mice injected in the footpad with carrageenin developed local inflammation which peaked at 48 hr. This delayed-type footpad swelling was significantly reduced in mice injected intraperitoneally (i.p.) with a specific nitric oxide (NO) synthase inhibitor, L-NGmonomethyl-arginine (L-NMMA). The draining lymph node (DLN) cells from mice injected 48 hr previously with carrageenin produced significantly higher levels of proliferation and interleukin-1 (IL-1), IL-2, IL-6 and interferon-gamma (IFN-gamma), but less IL-10, compared to cells from saline-injected controls, when stimulated with concanavalin A (Con A) in vitro. Treatment of the carrageenin-injected mice with L-NMMA had little effect on the proliferative response of the DLN cells, but significantly reduced the production of IL-1, IL-2, IL-6 and IFN-gamma, and increased the secretion of IL-10. These data demonstrate that NO plays a significant role in local inflammation and the pattern of cytokines induced in this model. 相似文献
998.
MA Mayoux-Benhamou JP Barbet F Bargy C Vallée M Revel 《Surgical and radiologic anatomy : SRA》1990,12(3):181-185
Summary Biomechanical models of the cervical spine require knowledge of the position, size and orientation of the individual muscles that act on the cervical spine. We have developed a technique to stereometrically measure anatomical specimens. The apparatus is composed of three graduated metallic rods, which slide along a fixed support. This method is accurate to map the anatomy of individual muscles and provides quantitative data on their lines of action. Results are obtained from one specimen. The computer processing of the collected data allows formulation of a three-dimensional model of the neck muscles in man.
Méthode d'étude anatomique quantitative des muscles de la nuqueEtude préliminaire
Résumé Pour élaborer un modèle biomécanique de la colonne cervicale, il faut connaître la position, la taille et l'orientation des différents muscles du cou. Nous avons mis au point une méthode de mesure stéréométrique sur des sujets anatomiques. L'appareil est composé de 3 axes métalliques gradués qui coulissent sur un support fixe. Cette technique permet une étude anatomique précise de chacun des muscles de la nuque, fournissant des données quantitatives sur les différents faisceaux ou lignes d'action. Les résultats sont obtenus sur un sujet. Leur traitement informatique permettra l'élaboration d'un modèle mathématique tridimensionnel des muscles du cou chez l'homme.相似文献
999.
Subdiaphragmatic denervated, liver heated rats eat as much and as long as subdiaphragmatic denervated, non-heated rats. This points to vagus and/or splanchnic nerve afferentation from hepatic thermoreceptors. Left abdomen heated rats eat and drink as much as left abdomen non-heated rats. Since however they show some different behavior patterns, the intervention of other nerve fibers other than vagal and/or splanchnic fibers should be acknowledged in order to account for the different behavior pattern. 相似文献
1000.
Castagnola M Congiu D Denotti G Di Nunzio A Fadda MB Melis S Messana I Misiti F Murtas R Olianas A Piras V Pittau A Puddu G 《Journal of chromatography. B, Biomedical sciences and applications》2001,751(1):153-160
A reversed-phase high-performance liquid chromatography (HPLC) method with diode-array detection for the quantification of several human salivary peptides is described. Sample pretreatment consisted of the acidification of whole saliva by phosphate buffer. This treatment produced precipitation of mucins, alpha-amylases and other high-molecular-mass salivary proteins, simultaneous inhibition of intrinsic protease activities and reduction of sample viscosity. Direct HPLC analysis by diode-array detection of the resulting acidic sample allowed one to quantify histatin 1, histatin 3, histatin 5, statherin, as well as uric acid, in normal subjects. Moreover, the groups of peaks pertaining to proline-rich proteins and cystatins were tentatively identified. The method can be useful in assessing the concentration of salivary peptides from normal subjects and from patients suffering oral and/or periodontal diseases. 相似文献