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11.
12.
Fecal acidorrhea 总被引:3,自引:0,他引:3
L Bustos Fernández E Gonzalez A Marzi M I Ledesma de Paolo 《The New England journal of medicine》1971,284(6):295-298
13.
14.
The effects of co-culture with human fibroblasts on human embryo development in vitro and implantation 总被引:5,自引:0,他引:5
Wetzels AM; Bastiaans BA; Hendriks JC; Goverde HJ; Punt-van der Zalm AP; Verbeet JG; Braat DD 《Human reproduction (Oxford, England)》1998,13(5):1325-1330
In a human in-vitro fertilization (IVF) programme, the effect of co-
culture of embryos with human fibroblasts was evaluated with respect to
pregnancy rate and embryo development. Patients were included in the study
after giving informed written consent. The IVF treatments were randomly
assigned by stratification of both age (<36 versus > or =36 years)
and previous IVF attempts (yes versus no). After fertilization was
established, the zygotes were transferred to a 4-well dish with or without
fibroblasts and cultured for 2 days. On the third day after ovum pick-up
(OPU), cell number and quality [5 (good) to 1 (poor)] of the embryos were
scored and a maximum of three embryos was transferred. Supernumerary
embryos of good quality were cryopreserved. The design of this study was a
group sequential trial with the objective of detecting differences between
pregnancy rates following IVF with conventional incubation or incubation in
co-culture with fibroblasts. This design included one evaluation at
half-way data collection. In the study, 148 patients had an OPU, of whom 77
were allocated to the co-culture group. There was no statistically
significant difference in pregnancy rate, cell number and embryo quality
between the two groups. The ongoing pregnancy rate per embryo transfer was
27% in co-culture and 30% in the conventional culture group. The
implantation rates per transferred embryo were 17 and 18% respectively.
Using a multivariate logistic regression model for the probability of
ongoing pregnancies, the odds ratio of co-culture, adjusted for age and
previous IVF attempts, was not statistically significant. In conclusion,
co-culture with human fibroblasts does not contribute to an improvement of
embryo quality nor to a higher pregnancy rate after IVF in an unselected
group of patients.
相似文献
15.
Histones interact with anionic phospholipids with high avidity; its relevance for the binding of histone-antihistone immune complexes. 下载免费PDF全文
L F Pereira F M Marco R Boimorto A Caturla A Bustos E G De la Concha J L Subiza 《Clinical and experimental immunology》1994,97(2):175-180
Antibodies recognizing anionic phospholipids have been described in systemic lupus erythematosus (SLE) and other autoimmune diseases. Recent studies have shown that some of these antibodies may recognize a cardiolipin-binding protein (apolipoprotein H) rather than phospholipids. A similar possibility is conceivable for other cardiolipin-binding proteins that are targets of autoantibodies. In this study we have addressed whether this might be the case for histones, a set of highly cationic and widely distributed proteins that react in a well known autoantibody system. Our results indicate that: (i) histones bind to anionic phospholipids (cardiolipin and phosphatidylserine) with high avidity, but not to zwitterionic phospholipids (phosphatidylcholine); (ii) monoclonal and polyclonal antihistone antibodies recognize histones bound to cardiolipin; (iii) the addition of histones to serum samples containing antihistone antibodies often enhances their anticardiolipin reactivity. In addition, we have found that antihistone-producing hybridomas derived from MRL-lpr mice may show anticardiolipin activity due to the presence of histones in the cell culture supernatants with the resultant formation of immune complexes. Taken together, the results suggest a potential role for histones in the anti-cardiolipin activity detected in sera containing antihistone antibodies. These histone-phospholipid interactions should be taken into account when evaluating the pathogenic effects of antihistone antibodies or other autoantibodies reacting with nuclear components (e.g. nucleosomes) containing histones. 相似文献
16.
The latest remarkable technological advances in assisted reproduction,
which enable cryopreservation of spermatozoa, embryos and ovarian tissue,
raise difficult and debatable legal, social, ethical and moral issues
concerning the right to posthumous reproduction. Furthermore, reports on
the attitudes of the general public and of centres licensed for infertility
treatment in the United Kingdom found that the majority of women and
centres support the idea of posthumous reproduction. In this paper we
review the data published on this issue, and after considering the various
aspects, we conclude that each case should be discussed and authorized by a
multidisciplinary committee that includes physicians, clergy,
psychiatrists, psychologists, sociologists and other appropriate parties.
In our opinion, the main principles that should guide this committee would
allow posthumous reproduction in the context of marriage when a prior
consent exists. For unmarried persons, post-mortem donation of gametes
should be done only anonymously, if they are in agreement with existing
laws concerning infertility treatments in every country and after
appropriate consent and proper counselling. Moreover, any case which
involves consanguinity or a possibility of incest should be forbidden, both
for ethical and genetic reasons. In a case of pre-existing siblings, they
should be consulted and their informed consent should be granted in advance
so as to avoid legal problems in the inheritance of property.
相似文献
17.
JJ Favre Ph Chaffanjon JG Passagia JP Chirossel 《Surgical and radiologic anatomy : SRA》1995,17(2):133-138
Summary The authors report the results of a series of dissections and anatomic sections of the fronto-basal region of the brain and of the anterior cranial fossa in human cadavers. The constant presence of an arachnoidal cistern above the olfactory nerve was verified. The arachnoid separates from the pial membrane and forms a bridge with the ventral part of the olfactory bulb and tract, from the lateral edge of the olfactory sulcus to the medial edge of the gyrus rectus. The cistern is wide in its anterior portion, between the gyrus rectus and the olfactory bulb, and is reduced to a virtual slit in its posterior portion where the tract is lodged in the olfactory sulcus. The olfactory nerve can be separated without damaging fronto-basal arachnoidial adhesions over several centimeters. Dissection of this region after intravascular injection of colored media shows the constant presence of an artery destined to the olfactory bulb and tract. It originates either from the lateral surface of the anterior cerebral a. (segment A2), or from the medial fronto-basal a., and consistently provides terminal branches in front of the olfactory trigone in the medial olfactory sulcus. At their ventral extremity, the olfactory structures are therefore vascularised independently for several centimeters, from the lower face of the frontal lobe. The independent vascularisation of the olfactory nerve, the tenuous and easily detachable adhesions, and the actual presence of a true arachnoidal cistern all contribute to enabling surgical techniques which conserve olfactory function during anterior approaches.
Vascularisation du nerf olfactif. Rapports méningés et applications chirurgicales
Résumé Les auteurs rapportent les résultats d'une série de dissections et de coupes de la région fronto-basale de l'encéphale et de la fosse crânienne antérieure sur sujets cadavériques. La présence constante d'une citerne arachnoïdienne au dessus du n. olfactif a été vérifiée. L'arachnoïde se sépare du feuillet pial et passe en pont à la partie ventrale du bulbe et du tractus olfactifs, du bord latéral du sillon olfactif au bord médial du gyrus rectus. La citerne est large dans sa portion antérieure, entre le gyrus rectus et le bulbe olfactif, se réduit à une fente virtuelle postérieure lorsque le tractus se loge dans le sillon olfactif. Le n. olfactif peut être séparé sans dommage des adhérences arachnoïdiennes fronto-basales sur quelques centimètres. La dissection de cette région, après injection intravasculaire de masses colorées montre, de façon originale, la présence constante d'une artère destinée au tractus et au bulbe olfactifs. Elle naît soit de la face latérale de l'a. cérébrale antérieure (segment A2), soit de l'a. fronto-basale médiale, pour donner ses branches terminales toujours en avant du trigone olfactif dans le sillon orbitaire médial. Sur quelques centimètres à leur extrémité ventrale, les structures olfactives ont donc une vascularisation indépendante de la face inférieure du lobe frontal. L'indépendance vasculaire du n. olfactif, des adhérences ténues, facilement détachables, et la réalité vérifiée d'une véritable citerne arachnoïdienne permettent d'imaginer des techniques conservatrices de la fonction olfactive utilisées dans plusieurs indications de la chirurgie de la fosse crânienne antérieure.相似文献
18.
Summary. BCH4 cells, persistently infected with Human Respiratory Syncytial Virus (HRSV), were obtained by Fernie et al. [12] after
infection of a BALB/c mouse embryo cell line with the Long strain of HRSV. To understand the basis of HRSV persistence, the
expression of HRSV RNAs and proteins was evaluated in BCH4 cells and infected parental BALB/c and fully permissive HEp-2 cells.
Production of viral mRNAs was severely impaired in BCH4 cells. In addition, the expression level of the surface glycoproteins
F and G was markedly reduced relative to internal viral proteins. However, virus recovered from BCH4 cells could lytically
infect HEp-2 cells and expressed normal levels of surface glycoproteins. No evidence of defective genomes or interfering particles
was found in BCH4 cells. Taken together, these data indicate that reduction of both viral mRNA accumulation and surface glycoprotein
biosynthesis are at the basis of HRSV persistence in BCH4 cells.
Accepted November 3, 2000 相似文献
19.
Cyclosporin A (CsA) modulates the glomerular production of inflammatory mediators and proteoglycans in experimental nephrosis. 总被引:1,自引:0,他引:1 下载免费PDF全文
C Bustos S Gonzlez-Cuadrado M Ruiz-Ortega C Gmez-Guerrero E Gonzlez J J Plaza J Egido 《Clinical and experimental immunology》1995,102(3):608-613
Nephrosis is characterized by glomerular epithelial cell injury and a decrease in the glomerular basement membrane (GBM) proteoglycan content. Although CsA is a useful treatment for a group of patients with this disease, its mechanism of action is unclear. We have previously shown that in experimental nephrosis there is an increase in the glomerular production of tumour necrosis factor-alpha (TNF-alpha) and platelet-activating factor (PAF). Here we have studied the effect of CsA on kidney generation of TNF-alpha and PAF in puromycin aminonucleoside (PAN) nephrosis as well as on the synthesis of proteoglycans by cultured glomerular epithelial cells. Rats receiving CsA had, on day 8 of PAN injection, a significant reduction in proteinuria, blood cholesterol levels and in interstitial mononuclear cells. A diminution in glomerular production and urinary excretion of TNF-alpha and PAF was also noted. In in vitro studies, at 24 h of incubation PAF and TNF-alpha induced in glomerular epithelial cells a significant decrease in proteoglycan synthesis. Neither PAF nor TNF-alpha had any significant effect on glomerular epithelial cell proliferation. CsA alone induced a dose-response increase in proteoglycan synthesis and a slight decrease in cell proliferation. CsA also reversed the inhibitory effect of PAF and TNF-alpha on proteoglycan synthesis. However, CsA did not alter the pattern of proteoglycan production, remaining around 50% chondroitinase ABC-, 15% heparitinase-sensitive. Our results indicate that PAF and TNF-alpha could be implicated in the pathogenesis of nephrosis through the inhibition of proteoglycan synthesis by glomerular epithelial cells. The beneficial effect of CsA in nephrosis may be due to the recovery of the GBM charge selectivity caused by the normalization of glomerular PAF and TNF-alpha synthesis and the increase in proteoglycan synthesis by glomerular epithelial cells. 相似文献
20.
Sonia Ehrlich Tania Bustos Inder J. Paika Aubrey Milunsky John M. Opitz 《American journal of medical genetics. Part A》1983,15(2):261-263
Some variation in the phenotype of patients with dup(18q) is recognized. Our patient has the phenotype described for dup(18qter). 相似文献