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排序方式: 共有1018条查询结果,搜索用时 15 毫秒
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Silber SJ; Nagy Z; Devroey P; Tournaye H; Van Steirteghem AC 《Human reproduction (Oxford, England)》1997,12(11):2422-2428
The aim of the study was to determine whether a prior diagnostic testicle
biopsy can predict success or failure of testicular sperm extraction (TESE)
with intracytoplasmic sperm injection (ICSI) in patients with
non-obstructive azoospermia caused by testicular failure, and what is the
minimum threshold of sperm production in the testis which must be surpassed
for spermatozoa to reach the ejaculate. Forty- five patients with
non-obstructive azoospermia caused by testicular failure underwent
diagnostic testicle biopsy prior to a planned future TESE-ICSI procedure.
The diagnostic testicle biopsy was analysed quantitatively, and correlated
with the quantitative findings of spermatogenesis in patients with normal
spermatogenesis, as well as with the results of subsequent attempts at
TESE-ICSI. Men with non- obstructive azoospermia caused by germinal failure
had a mean of 0-6 mature spermatids/seminiferous tubule seen on a
diagnostic testicle biopsy, compared to 17-35 mature spermatids/tubule in
men with normal spermatogenesis and obstructive azoospermia. These findings
were the same for all types of testicular failure whether Sertoli cell
only, maturation arrest, cryptorchidism, or post-chemotherapy azoospermia.
Twenty-two of 26 men with mature spermatids found in the prior testis
biopsy had successful retrieval of spermatozoa for ICSI, 12 of their
partners became pregnant, and are either ongoing or delivered. The study
suggests that 4-6 mature spermatids/tubule must be present in the testis
biopsy for any spermatozoa to reach the ejaculate. More than half of
azoospermic patients with germinal failure have minute foci of
spermatogenesis which are insufficient to produce spermatozoa in the
ejaculate. Prior diagnostic testicle biopsy analysed quantitatively (for
the presence of mature spermatids) can predict subsequent success or
failure with TESE-ICSI. Incomplete testicular failure may involve a sparse
multi-focal distribution of spermatogenesis throughout the entire testicle,
rather than a regional distribution. Therefore, it is possible that massive
testicular sampling from many different regions of the testes may not be
necessary for successful TESE-ICSI.
相似文献
4.
β-Lactoglobulin was isolated from infant formulae that were ultra high temperature (UHT) -treated, sterilized or spray-dried. The effect of the isolated β-lactoglobulin on SfaII-fimbriae-mediated adhesion of Escherichia coli to human ileostomy glycoproteins was studied in vitro. β-Lactoglobulin isolated from sterilized formulae was found to perform significantly less well than preparations from spray-dried formulae (p = 0:05). Great heterogeneity was observed in the adhesion inhibitory capacity of β-lactoglobulin isolated from UHT-treated formulae. Therefore, no significant difference was observed between UHT-treated and sterilized formulae or spray-dried formulae (p < 0:10). It can be hypothesized that β-lactoglobulin from spray-dried and some UHT-treated infant formulae may affect the colonization of mucous membranes by E. coli strains causing neonatal septicaemia and meningitis. 相似文献
5.
Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
相似文献
6.
Van de Velde H; De Vos A; Joris H; Nagy ZP; Van Steirteghem AC 《Human reproduction (Oxford, England)》1998,13(11):3160-3164
In human in-vitro fertilization (IVF), the oocytes are surrounded by
cumulus and corona cells at the time of insemination so that their maturity
cannot easily be evaluated. The best IVF results are obtained if the
oocytes are inseminated 2-6 h after retrieval. In the intracytoplasmic
sperm injection (ICSI) procedure, the oocytes are denuded by enzymatic and
mechanical treatment in order to be able to perform the injection. As a
consequence, the nuclear maturity of the oocytes can be evaluated and only
those that have extruded the first polar body are injected. However,
metaphase-II oocytes that have not yet reached cytoplasmic maturity cannot
be recognized. The purpose of this study was to investigate the effect of
different timing of cumulus- corona cell removal and injection on the
outcome of ICSI. For this we allowed the oocytes to complete in-vitro
cytoplasmic maturation in two different culture conditions: (i) surrounded
by their cumulus and corona cells or (ii) totally denuded. We performed
three different studies on sibling oocytes obtained after a standardized
buserelin/human menopausal gonadotrophin (HMG) protocol. We investigated
the effect of early (1-2 h after retrieval) and late (5-6 h after
retrieval) oocyte denudation and injection on the survival and
fertilization of the injected oocytes and on embryo cleavage after
fertilization. We found no statistically significant differences between
early and late injection, indicating that after a standardized
buserelin/HMG protocol the metaphase-II oocytes do not need time for
further cytoplasmic maturation. Furthermore, a different timing of
cumulus-corona cell removal has no effect on the outcome of ICSI,
suggesting that the surrounding cells are not necessary for survival,
fertilization and cleavage after ICSI.
相似文献
7.
Novero V; Camus M; Tournaye H; Smitz J; Verheyen G; Joris H; Derde MP; Van Steirteghem AC; Devroey P 《Human reproduction (Oxford, England)》1997,12(1):59-63
Serum follicle stimulating hormone (FSH) is routinely measured when
evaluating the infertile male for intracytoplasmic sperm injection (ICSI).
However, among the sperm parameters, only its relationship with sperm
concentration is well documented. Few investigations concern the
relationship between FSH and sperm motility and morphology, and the results
of ICSI. A retrospective study of 316 couples who underwent ICSI was
carried out to determine the relationships between serum FSH concentrations
in the male and (i) standard sperm parameters_(concentration, motility and
morphology) and (ii) fertilization, cleavage, pregnancy and implantation
rates after ICSI. There was an inverse correlation with sperm concentration
and total motility but no relationship was found with progressive motility
and sperm morphology. Neither was any relationship found between serum FSH
and fertilization, cleavage, pregnancy and implantation rates, and the
results of ICSI. These findings suggest the need to review the routine
measurement of serum FSH in the infertile male when ICSI is the planned
treatment procedure.
相似文献
8.
SDF-1 induces IL-8 production and transendothelial migration of human cord blood-derived mast cells 总被引:3,自引:0,他引:3
Lin TJ Issekutz TB Marshall JS 《International archives of allergy and immunology》2001,124(1-3):142-145
BACKGROUND: Mast cell numbers and expression of chemokines are known to increase in the context of angiogenesis and inflammation, but the mechanisms by which this occurs are not understood. Stromal-derived factor-1 (SDF-1) is an important chemokine in angiogenesis and cell migration. The effects of SDF-1 on human mast cells were examined. METHODS: Expression of the SDF-1 receptor CXC chemokine receptor 4 (CXCR4) on mast cells was examined by RT-PCR and flow cytometry. The ability of labeled cord blood-derived mast cells to migrate across HUVEC monolayers in response to SDF-1 was determined. The cytokine and chemokine responses of cord blood-derived mast cells to SDF-1 treatment over 24 h were examined by ELISA. RESULTS: Cord blood-derived human mast cells expressed the CXCR4 receptor for SDF-1 and migrated across HUVEC monolayers in response to this chemokine. Treatment of cord blood-derived mast cells with SDF-1 did not induce degranulation or the production of several cytokines but did induce a highly selective IL-8 response. CONCLUSION: Human mast cells can both migrate across vascular endothelium and produce the pro-angiogenic chemokine IL-8 in response to SDF-1. These responses may be important in angiogenic processes. 相似文献
9.
Enhanced vascular permeability and haemorrhage-inducing activity of rabbit C5ades arg: probable role of polymorphonuclear leucocyte lysosomes. 总被引:10,自引:2,他引:10 下载免费PDF全文
We previously reported that the injection into rabbit skin of rabbit zymosan-activated plasma (ZAP) induces marked polymorphonuclear leucocyte (PMN) infiltration, a transient increase in vascular permeability (1 hr) and prolonged red blood cells extravasation lasting at least 10 hr. Here we describe the fractionation of ZAP to identify the factor(s) responsible for these effects. On CM Sephadex G-25 chromatography, the majority of the leucocyte-attracting, permeability-enhancing and haemorrhage-inducing activities eluted in the high-salt fractions (0 . 6 M ammonium formate, 1 M NaCl pH 5 . 0), suggesting that this is a very basic molecule(s). Furthermore, the three activities eluted in the same fraction on Sephadex G-100, with an apparent molecular weight of 14,000--17,000 daltons. These observations, and the previously described requirement for C5 in the plasma, suggest that C5ades arg is the active factor. Experiments performed in neutropenic rabbits indicated that PMN are required for both the increase in permeability and red cell extravasation. Ultrastructural studies showed extensive degenerative changes in the infiltrating PMNs evident even in 1--2-hr lesions. These ranged from 'watery' cytoplasm, loss of glycogen and cell membrane to segregation and extensive extracellular release of lysosomes. It is postulated that C5ades arg-induced chemotaxis and metabolic perturbations contribute to this rapid degeneration of the PMNs, and that the release of lysosomes from these cells results in progressive vascular injury. 相似文献
10.
The effect of vasodilator prostaglandins on polymorphonuclear leukocyte infiltration and vascular injury. 总被引:4,自引:8,他引:4 下载免费PDF全文
Some severe acute inflammatory reactions are characterized by polymorphonuclear leukocyte (PMN) infiltration as well as vascular and tissue damage with hemorrhage. Two types of mediators that may be involved in such reactions are chemotactic factors and prostaglandins. The chemotactic factors can induce PMN infiltration, while some types of prostaglandins cause vasodilatation. We reported previously that injection of soluble, nonphagocytosable chemotactic stimuli, zymosan-activated plasma (ZAP), or C5a des Arg into rabbit skin induced PMN-dependent hemorrhage. Here we investigated whether prostaglandins may modulate the rate of PMN infiltration, measured with 51Cr-labeled leukocytes and the degree of hemorrhage, measured with 59Fe-labeled red cells. Prostaglandin (PG) E1 (0.5 microgram) or E2 (1 microgram) increased ZAP-induced PMN accumulation by 81% and hemorrhage by 400%. A similar potentiation by PGE2 was observed when submaximal concentrations of ZAP were injected. Prostaglandin F2 alpha had no such effect. These results indicate that the degree of PMN infiltration of the tissues may be one factor determining the severity of vascular damage. Furthermore, vasodilatory prostaglandins, generated during neutrophilic inflammatory reactions, may enhance chemotactic-factor-mediated PMN infiltration and increase the extent of vascular injury. 相似文献