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101.
Greg V. Stiegmann John S. Goff John H. Sun Deborah Davis Dean Silas 《Surgical endoscopy》1989,3(2):73-78
Summary Endoscopic variceal ligation (EVL) is a new technique designed to be used instead of sclerotherapy. Small elastic O rings ligate varices resulting in their strangulation and eradication. During a 12-month period, EVL was employed in 53 consecutive patients, of whom 36 (68%) had alcoholic cirrhosis 17 were Child-Pugh class A, 22 class B, and 14 class C. Varices were graded from I to IV and repeat treatments were given at 1–2 week intervals until the varices were eliminated. At follow-up ranging from 6–18 months (mean 11.5), 217 EVL treatment sessions had been performed. Of the 13 patients (24%) who died during the study, 11 died during the index hospitalization. Active bleeding was controlled in 19 of 21 patients (90%). Of 40 survivors 13 patients (33%) had 1–2 (mean 1.4) recurrent variceal bleeds while 34 patients had repeat EVL treatment. Elimination of distal varices was achieved in 26 and 7 had reduction of varices from grade III–IV to grade I–II or less. Eradication required a mean of 4.4 EVL sessions in Child's A and B patients and 7.0 sessions in Child's C patients (P<0.025). No significant treatment-related complications were observed. EVL appears to control active bleeding, is associated with a low incidence of non-bleeding complications, and may be used as an alternative to sclerotherapy. 相似文献
102.
Pierre-Andr Bcherel Liliane Le Goff Sandra Ktorza Fateh Ouaaz Jean-Michel Mencia-Huerta Bernard Dugas Patrice Debr M. Djavad Mossalayi Michel Arock 《European journal of immunology》1995,25(10):2992-2995
Human keratinocytes (HK) generate nitric oxide (NO) and proinflammatory mediators following activation with either IgE/anti-IgE immune complexes or a combination of lipopolysaccharide (LPS) and interferon-γ (IFN-γ). Recently, interleukin-10 (IL-10) has been shown to down-regulate various inflammatory responses and to be secreted by lymphocytes and dendritic cells during skin inflammatory reactions. We show here that IL-10 down-regulates the production of tumor necrosis factor (TNF)-α and IL-6 by activated HK. Also, induction of inducible nitric oxide synthase (iNOS) expression in HK by IgE/anti-IgE or LPS/IFN-γ is significantly reduced by the addition of IL-10. This effect is dose dependent and correlates with reduction of iNOS mRNA production and enzyme level. Therefore, IL-10 down-regulates NO-mediated HK inflammatory responses and may thus participate in the regulation of the skin immune network. 相似文献
103.
Endoscopic sclerotherapy as compared with endoscopic ligation for bleeding esophageal varices. 总被引:30,自引:0,他引:30
G V Stiegmann J S Goff P A Michaletz-Onody J Korula D Lieberman Z A Saeed R M Reveille J H Sun S R Lowenstein 《The New England journal of medicine》1992,326(23):1527-1532
BACKGROUND. Endoscopic sclerotherapy is an accepted treatment for bleeding esophageal varices, but it is associated with substantial local and systemic complications. Endoscopic ligation, a new form of endoscopic treatment for bleeding varices, may be safer. We compared the effectiveness and safety of the two techniques. METHODS. In this randomized trial we compared endoscopic sclerotherapy and endoscopic ligation in 129 patients with cirrhosis who had proved bleeding from esophageal varices. Sixty-five patients were treated with sclerotherapy, and 64 with ligation. Initial treatment for acute bleeding was followed by elective retreatment to eradicate varices. The patients were followed for a mean of 10 months, during which we determined the incidence of complications and recurrences of bleeding, the number of treatments needed to eradicate varices, and survival. RESULTS. Active bleeding at the first treatment was controlled by sclerotherapy in 10 of 13 patients (77 percent) and by ligation in 12 of 14 patients (86 percent). Slightly more sclerotherapy-treated patients had recurrent hemorrhage during the study (48 percent vs. 36 percent for the ligation-treated patients, P = 0.072). The eradication of varices required a lower mean (+/- SD) number of treatments with ligation (4 +/- 2 vs. 5 +/- 2, P = 0.056) than with sclerotherapy. The mortality rate was significantly higher in the sclerotherapy group (45 percent vs. 28 percent, P = 0.041), as was the rate of complications (22 percent vs. 2 percent, P less than 0.001). The complications of sclerotherapy were predominantly esophageal strictures, pneumonias, and other infections. CONCLUSIONS. Patients with cirrhosis who have bleeding esophageal varices have fewer treatment-related complications and better survival rates when they are treated by esophageal ligation than when they are treated by sclerotherapy. 相似文献
104.
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
105.
Babesia bovis merozoite proteins presenting as exoantigens in in vitro culture supernatants have been characterized. Bovine antisera to
B. bovis exoantigens were used to immunoprecipitate [35S]-methionine metabolically labeled or lactoperoxidase-catalyzed radioiodinated B. bovis merozoite proteins. A total of 24 metabolically labeled proteins ranging in molecular weight from 24,000 to 225,000 Da and
9 radioiodinated proteins with molecular weights varying between 24,000 and 225,000 Da were identified by sodium dodecyl sulfate-polyacrylamide
gel electrophoresis. Monoclonal antibodies to B. bovis merozoite surface proteins were also used to immunoprecipitate metabolically labeled exoantigens directly from in vitro culture
supernatants. These results demonstrate epitopes from at least nine merozoite surface proteins present in the exoantigen fraction,
among which are the recently characterized major surface antigens 1 and 2, rhoptry-associated protein 1, and spherical body
protein 2.
Received: 1 April 1997 / Accepted: 6 May 1997 相似文献
106.
Hydrosalpinges adversely affect markers of endometrial receptivity 总被引:22,自引:10,他引:22
Meyer WR; Castelbaum AJ; Somkuti S; Sagoskin AW; Doyle M; Harris JE; Lessey BA 《Human reproduction (Oxford, England)》1997,12(7):1393-1398
While in-vitro fertilization (IVF) was initially developed in women with
tubal factor infertility, recent clinical studies have suggested that the
presence of hydrosalpinges lowers implantation and pregnancy rates. We
postulated that these hydrosalpinges cause impaired endometrial
receptivity. A total of 103 women with hydrosalpinges were prospectively
evaluated, and compared with 55 infertile and 44 fertile controls. All
women had endometrial biopsies during the window of implantation, analysed
by conventional histological criteria, and also stained for three integrin
markers of endometrial receptivity (alpha1beta1, alpha4beta1 and alpha
vbeta3). Women with hydrosalpinges (cases) expressed significantly less of
the alpha vbeta3 integrin compared with controls. There was no difference
in expression of alpha1beta1 or alpha4beta1 among groups. A significantly
greater number of cases had out of phase histology and missing alpha vbeta3
(type I defects) and absent integrin expression despite normal histological
maturation (type II) defects, compared with controls. Of 20 women with
impaired endometrial receptivity who were also biopsied after hydrosalpinx
surgery, 70% demonstrated increased alpha vbeta3 expression. Seventy-seven
percent of type I and 57% of type II defects were corrected
postoperatively. Using markers of endometrial receptivity, this study
demonstrates that inflammatory hydrosalpinges have an adverse effect on
endometrial receptivity, which in some cases may be overcome by surgical
treatment of the hydrosalpinx.
相似文献
107.
Point mutations in the P30 domain of the gag gene of Moloney murine leukemia virus 总被引:22,自引:0,他引:22
A series of point mutations in the P30 domain of the Moloney murine leukemia virus gag gene was generated by bisulfite treatment of heteroduplex DNAs containing a single-stranded region in the gag gene. One virus bearing such a mutation exhibited a coordinate defect in gag and pol function, and was similar to previously described deletion mutants with alterations in this gene. One mutant virus displayed a different phenotype: it could assemble virion particles and provide pol function, but the particles were defective in the early stages of infection. The continued concordance of the mutants' failure or ability to both assemble virions and provide pol lends further support to the proposal that similar parts of the gag gene are required for these two processes. 相似文献
108.
109.
110.
Sequence comparison of human and yeast telomeres identifies structurally distinct subtelomeric domains 总被引:6,自引:2,他引:6
Flint J; Bates GP; Clark K; Dorman A; Willingham D; Roe BA; Micklem G; Higgs DR; Louis EJ 《Human molecular genetics》1997,6(8):1305-1313
We have sequenced and compared DNA from the ends of three human
chromosomes: 4p, 16p and 22q. In all cases the pro-terminal regions are
subdivided by degenerate (TTAGGG)n repeats into distal and proximal sub-
domains with entirely different patterns of homology to other chromosome
ends. The distal regions contain numerous, short (<2 kb) segments of
interrupted homology to many other human telomeric regions. The proximal
regions show much longer (approximately 10-40 kb) uninterrupted homology to
a few chromosome ends. A comparison of all yeast subtelomeric regions
indicates that they too are subdivided by degenerate TTAGGG repeats into
distal and proximal sub-domains with similarly different patterns of
identity to other non-homologous chromosome ends. Sequence comparisons
indicate that the distal and proximal sub-domains do not interact with each
other and that they interact quite differently with the corresponding
regions on other, non- homologous, chromosomes. These findings suggest that
the degenerate TTAGGG repeats identify a previously unrecognized,
evolutionarily conserved boundary between remarkably different subtelomeric
domains.
相似文献