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排序方式: 共有271条查询结果,搜索用时 31 毫秒
1.
2.
Summary. During the course of sterility treatment semenograms of 271 IVF and 316 insemination patients were carried out by two automated semen analysers. The parameters of these analyses were correlated to pregnancies resulting from the treatment. Semen samples were analysed in the ejaculate and after swim-up preparation. In addition, the swim-up suspension of IVF patients was measured again 18 h after sperm preparation. Patients were divided into three groups: (1) couples who achieved a pregnancy, (2) couples who did not achieve a pregnancy, and (3) IVF patients with no fertilization of the oocytes. Because of large standard deviations in the quality of ejaculates, the results in the IVF group show no significant differences in the semen parameters of husbands of pregnant and non-pregnant women. In contrast husbands of women with no fertilization have a significantly lower sperm motility. After swim-up preparation these differences no longer occur. A further measurement, taken 18 h later, reveals that there are no differences in the sperm parameters between the pregnant and non-pregnant group. However, the semen quality in the group with no fertilization is significantly reduced. The results of the insemination patients are similar to those of the IVF group. Thus, the results from automated sperm analysers cannot replace either the microscopic or biochemical analysis of an ejaculate and, moreover, cannot be used as prognosis for the fertilization capacity of sperms or a following pregnancy. 相似文献
3.
Calcium ionophore-induced acrosome reaction correlates with fertilization rates in vitro in patients with teratozoospermic semen 总被引:5,自引:3,他引:5
The aim of this study was to determine the relationship between calcium
ionophore A23187-induced acrosome reaction (AR) and sperm fertilizing
ability. Semen samples remaining after preparation for standard IVF were
studied in 109 patients who had sperm concentrations > or =20 x
10(6)/ml. Ionophore-induced AR was performed on motile spermatozoa selected
by centrifugation on a Percoll gradient. Semen analysis was performed using
standard methods. Patients with higher (>50%, n = 76) fertilization
rates had significantly higher ionophore-induced AR than patients with
lower (<50%, n = 33) fertilization rates (49 +/- 14 versus 38 +/- 21%, P
< 0.05). When the data from all patients were analysed by logistic
regression, only the percentage sperm motility in insemination medium and
ionophore-induced AR were significantly related to fertilization rates.
Similar results were also obtained when the data from a subgroup of
patients with poor (<15% normal) sperm morphology were analysed.
However, when patients with normal sperm morphology > or =15% were
analysed separately, only sperm count and the percentage of spermatozoa
with progressive motility in semen were significantly related to
fertilization rates. In conclusion, ionophore- induced AR was significantly
related to fertilization rates in vitro mainly in patients with
teratozoospermic semen. Tests for ionophore- induced AR may provide
additional information about sperm fertilizing ability but may not indicate
specific defects of the physiological AR.
相似文献
4.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture
environment differs from in-vivo conditions in that the oxygen
concentration is higher, and in such conditions the mouse embryos show a
higher concentration of reactive oxygen species (ROS) in simple culture
media. ROS are believed to cause damage to cell membranes and DNA
fragmentation in somatic cells. This study was conducted to ascertain the
level of H2O2 concentration within embryos and the morphological features
of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31
fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was
obtained from the IVF-embryo transfer programme. The relative intensity of
H2O2 concentrations within embryos was measured using
2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence
imaging and DNA fragmentation was observed with transmission electron
microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations
were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/-
SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and
unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed
only in fragmented embryos, and was absent in non-fragmented embryos.
Electron microscopic findings confirmed apoptotic bodies and cytoplasmic
condensation in the fragmented blastomeres. We conclude that there is a
direct relationship between increased H2O2 concentration and apoptosis, and
that further studies should be undertaken to confirm these findings.
相似文献
5.
Stein TP; Oram-Smith JC; Leskiw MJ; Wallace HW; Long LC; Leonard JM 《The American journal of physiology》1976,230(5):1321-1325
6.
Interchromosomal duplications of the adrenoleukodystrophy locus: a phenomenon of pericentromeric plasticity 总被引:13,自引:5,他引:13
Eichler EE; Budarf ML; Rocchi M; Deaven LL; Doggett NA; Baldini A; Nelson DL; Mohrenweiser HW 《Human molecular genetics》1997,6(7):991-1002
A 9.7 kb segment encompassing exons 7-10 of the adrenoleukodystrophy (ALD)
locus of the X chromosome has duplicated to specific locations near the
pericentromeric regions of human chromosomes 2p11,10p11, 16p11 and 22q11.
Comparative sequence analysis reveals 92-96% nucleotide identity,
indicating that the autosomal ALD paralogs arose relatively recently during
the course of higher primate evolution (5-10 million years ago). Analysis
of sequences flanking the duplication region identifies the presence of an
unusual GCTTTTTGC repeat which may be a sequence-specific integration site
for the process of pericentromeric- directed transposition. The breakpoint
sequence and phylogenetic analysis predict a two-step transposition model,
in which a duplication from Xq28 to pericentromeric 2p11 occurred once,
followed by a rapid distribution of a larger duplicon cassette among the
pericentromeric regions. In addition to facilitating more effective
mutation detection among ALD patients, these findings provide further
insight into the molecular basis underlying a pericentromeric-directed
mechanism for non- homologous interchromosomal exchange.
相似文献
7.
Micromorphometry and spermatozoa binding patterns of fertilized and unfertilized human oocytes after in-vitro fertilization 总被引:2,自引:1,他引:2
Human oocytes (n = 380) from 71 in-vitro fertilization patientswere measured 18 h after insemination to find out if certainparameters of oocyte morphology could be related to fertilization.In addition, the number and distribution patterns of spermatozoabound to or within the zona pellucida of 534 oocytes were analysed.The mean diameter of the human oocyte was 167.7 ± 9.5µm and its mean volume was 2.5 x 106 µm3. Therewere no significant differences in diameter between 112 fertilizedand 168 unfertilized oocytes, although they displayed differencesin the size of the perivitelline space and the zona pellucida.The age of the patients had no significant effect on the morphometryof the oocytes. Sperm binding patterns did not correlate withfertilization. The number and distribution of the spermatozoaon the surface of the zona pellucida was extremely heterogeneousand was not related to the occurrence of fertilization. Allpossible binding and distribution patterns were in the samerange in both fertilized and unfertilized oocytes. In conclusion,the micromorphometry of human oocytes and their sperm bindingpatterns were not related to the occurrence of fertilization. 相似文献
8.
Clarke GN; Bourne H; Hill P; Johnston WI; Speirs A; McBain JC; Baker HW 《Human reproduction (Oxford, England)》1997,12(4):722-726
Donor insemination (DI) using cryopreserved semen commenced at The Royal
Women's Hospital in 1976. Over the next 15 years we performed 5953
treatment cycles to achieve 816 pregnancies (13.7% per cycle) and 706 live
births. In-vitro fertilization (IVF) using donor spermatozoa commenced in
1986. Over the next 5 years we performed 303 treatment cycles for 185
couples. Including subsequent transfer of cryopreserved embryos, a total of
33% of couples achieved a successful pregnancy by IVF. Statistical analysis
indicated that, for DI pregnancies, the most important semen variable was
the percentage post-thaw motility, whilst for normal fertilization in IVF
it was the pre-freeze motility. These results may be explained by the
compensatory effects of post-thaw processing of spermatozoa for IVF, but
not for DI in our clinic.
相似文献
9.
下消化道出血221例分析 总被引:4,自引:2,他引:2
0 引言 下消化道出血是消化科的常见病 ,是指十二指肠空肠移行部 ,屈氏韧带以下的小肠和大肠疾病引起的肠道出血 .有人认为一般不包括痔和肛裂出血 [1 ] .临床最常见为慢性出血 ,但有时出血量大危及生命 ,需要做紧急处理 ,现将我院1992 - 0 1/ 1999- 0 8门诊及病房收治的 2 2 1例下消化道出血进行分析 ,报告如下 :1 临床资料 男 12 0例 ,女 10 1例 ,年龄 14~ 72 (平均 42 )岁 ,病程 16 h~ 10 a.患者分别以脓血便、暗红色血便、鲜血便或果酱色血便为主诉前来就诊 ,其中有休克症状的大出血者6例 .血 Hb<110 g·L- 1 40例 ,<80 g·L- 1… 相似文献
10.
Magerkurth C Töpfer-Petersen E Schwartz P Michelmann HW 《Human reproduction (Oxford, England)》1999,14(4):1057-1066
Human oocytes from the same as well as from different patients have an extremely heterogeneous morphology of the zona pellucida surface as shown by scanning electron microscopy. For years it has been believed that this heterogeneous morphology plays an important part in the sperm-oocyte interaction. It was the aim of this investigation to analyse the morphology and the sperm binding patterns of the human zona pellucida. Oocytes were divided into four categories: mature, immature, fertilized and unfertilized. Four different types of zona morphology were detectable. They ranged from a porous, net-like structure to a nearly smooth and compact surface. No correlation could be established between zona type and oocyte maturity or zona type and achieved fertilization. However, fertilized (polyploid) oocytes had a more compact and smooth zona surface than unfertilized ones. The analysis of the number and distribution patterns of bound spermatozoa on the zona pellucida revealed extremely variable patterns regardless of the zona morphology. Significant differences between mature and immature oocytes did not appear. In both groups there were oocytes with either no or numerous bound spermatozoa on the zona pellucida. Oocytes overloaded with spermatozoa could only be found in the mature group. Unfertilized oocytes had fewer bound spermatozoa on average than polyploid zygotes. 相似文献