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41.
Is the outcome of in-vitro fertilization and embryo transfer treatment improved by spontaneous or surgical drainage of a hydrosalpinx? 总被引:4,自引:7,他引:4
Sowter MC; Akande VA; Williams JA; Hull MG 《Human reproduction (Oxford, England)》1997,12(10):2147-2150
A pilot study was designed to examine whether the outcome of embryo
transfer in women with a hydrosalpinx might be improved by surgical
drainage of the hydrosalpinx at the time of oocyte collection for in- vitro
fertilization treatment. A comparative, controlled but retrospective
analysis of the results was performed of all women with infective tubal
damage aged <40 years old, who had ovulatory cycles, a normal uterus and
a partner with normal spermatozoa. A standardized treatment regimen was
used. A maximum of three embryos were transferred. Hydrosalpinx was defined
by prior hysterosalpingography and/or laparoscopy with transcervical dye
injection. A total of 237 embryo transfer cycles in women with
hydrosalpinges (tubal distension not visible in 151, visible but not
drained in 30 and drained in 56) were compared with 705 embryo transfer
cycles in women with tubal disease but no hydrosalpinx. Results were
analysed in the first three cycles but also separately in the first cycle
to check for bias. Success rates were higher in the first cycle, but did
not significantly influence overall differences. Implantation rates were
significantly reduced overall in the hydrosalpinx group (8.0 versus 13.2%
for controls; P < 0.001), being 8.3% (P < 0.01) in the subgroup
without evident tubal distension and 7.5% (not significant) in the drained
hydrosalpinx group. This study shows that tubal damage with distal
occlusion is associated with a marked reduction in embryo implantation,
even in the absence of obvious fluid distension. Surgical drainage of
distended hydrosalpinges appears to offer no benefit.
相似文献
42.
43.
KM Kanal NJ Hangiandreou AM Sykes HE Eklund PA Araoz JA Leon BJ Erickson 《Journal of digital imaging》2002,14(1):30-37
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's
gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing
radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers,
and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed
with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant,
and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender
were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women
was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative
English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and
while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology
practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient
way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed
and sensitive manner. 相似文献
44.
Immunological factors in endometriosis-associated reproductive failure: studies in fertile and infertile women with and without endometriosis 总被引:7,自引:4,他引:7
Martinez-Roman S; Balasch J; Creus M; Fabregues F; Carmona F; Vilella R; Vanrell JA 《Human reproduction (Oxford, England)》1997,12(8):1794-1799
Immunopathophysiological mechanisms in endometriosis-associated
reproductive failure were studied in appropriate populations: infertile and
fertile women with and without endometriosis. The incidence of sera
positive for any of the autoantibodies tested among infertile women with
endometriosis (n = 25) was similar to that observed in the three control
groups [unexplained infertility patients (n = 25) and fertile women with (n
= 10) and without (n = 25) endometriosis]. The mean volume of peritoneal
fluid was significantly elevated in women with endometriosis (both fertile
and infertile) as compared with patients without endometriosis (fertile or
infertile). The concentration of peritoneal fluid leukocytes and the
percentage of cells positive for macrophage markers were significantly
increased and the percentage of T lymphocytes significantly decreased in
infertile women with endometriosis but not in patients with unexplained
infertility and fertile women with endometriosis, as compared with fertile
controls without endometriosis. Macrophages from infertile patients with
endometriosis had higher sperm phagocytosis than did those from infertile
women without endometriosis or fertile subjects with or without
endometriosis. Incidences of serum and peritoneal fluid samples embryotoxic
to the in-vitro development of 2-cell mouse embryos were significantly
higher in infertile patients with endometriosis than in unexplained
infertility patients and fertile women with or without endometriosis. It is
concluded that immunological mechanisms of endometriosis-associated
infertility exist but that these peritoneal immunological factors in
infertile women with endometriosis are related to their subfertility rather
than to the presence of ectopic endometrial implants. This is supported by
the lack of immunological abnormalities observed among fertile women with
endometriosis. These immunological abnormalities are lacking in patients
with unexplained infertility.
相似文献
45.
The ileoanal J pouch: radiographic evaluation 总被引:1,自引:0,他引:1
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through. 相似文献
46.
No evidence for paternal mtDNA transmission to offspring or extra-embryonic tissues after ICSI 总被引:6,自引:0,他引:6
Marchington DR Scott Brown MS Lamb VK van Golde RJ Kremer JA Tuerlings JH Mariman EC Balen AH Poulton J 《Molecular human reproduction》2002,8(11):1046-1049
There is a risk that ICSI may increase the transmission of mtDNA diseases to children born after this technique. Knowledge of the fate and transmission of paternal mitochondrial DNA is important since mutations in mitochondrial DNA have been described in oligozoospermic males. We have used an adaptation of solid phase mini-sequencing to exclude the presence of levels of paternal mtDNA >0.001% in ICSI families. This method is more sensitive than those used in previous studies and is sufficient to detect the likely paternal contribution (approximately 0.1-0.5% from simple calculations of expected dilution during fertilization). Using this method, we were able to detect concentrations as low as 0.001% paternal mtDNA in a maternal mtDNA background. No paternal mtDNA was detected in the embryonic (blood or buccal swabs) tissue of children born after ICSI nor in extra-embryonic tissue (placenta or umbilical cord). In conclusion, we did not detect paternal mtDNA in blood, buccal swabs, placenta or umbilical cord of children born after ICSI. We have found no evidence that ICSI increases the risk of paternal transmission of mtDNA and hence of mtDNA disorders. 相似文献
47.
Friedrich Weber Carsten Kremer Mario Klinkhammer Bettina Rasier Mario Brock 《Journal of neuro-oncology》1994,18(3):217-224
Summary This publication describes a new model to investigate the influence of tumor necrosis factor- (TNF-) on a three-dimensional glial cell aggregate under defined, standardized, reproducible conditions using the glioma cell line A 172.The cells are initially grown as normal monolayer culture until they reach a cell density of up to 1×106. Subsequently they are grown as spheroids by the liquid overlay technique. Spheroids grown in this way were divided into ten groups of more than 50 cell aggregates. Three groups were coincubated with free TNF- in increasing dosages (100 ng/ml, 200 ng/ml and 1000 ng/ml); three groups were incubated with empty liposomes (0.2 mg/ml, 0.4 mg/ml and 2 mg/ml); three groups received liposomes which had been loaded with TNF-, and one group, which received no treatment, served as control.The diameter of the spheroids ranged from 80 m to 350 m. There was no significant difference in growth between the 3 groups treated with free TNF-. Comparing spheroids treated with TNF- with those which had been coincubated with empty liposomes, there was a significant difference (p<0.001) in growth, which correlated with the amount of liposomes. Similarly, free TNF- had a significantly (P<0.001) stronger growth-inhibiting effect as compared to liposomes loaded with TNF-. Comparing the groups treated with liposomes only to those treated with liposomes loaded with TNF-, the latter exhibited a more marked (although not significantly) growth-inhibiting effect.The preliminary conclusion is that the major growth-inhibiting effect seems to be mediated by the liposomes. This phenomenon is in agreement with results obtained in monolayer cultures. 相似文献
48.
A. Aschoff P. Kremer C. Benesch K. Fruh A. Klank S. Kunze 《Child's nervous system》1995,11(4):193-202
When vertical body position is simulated, conventional differential pressure valves show an absolutely unphysiological flow, which is 2–170 times the normal liquor production rate. Although this is compensated in part by the resistance of the silicon tubes, which may produce up to 94% of the resistance of the complete shunt system, a negative intracranial pressure (ICP) of up to 30–44 cmH2O is an unavoidable consequence, which can be followed by subdural hematomas, slit ventricles, and other well-known complications. Modern shunt technology offers programmable, hydrostatic, and flow-controlled valves and anti-siphon devices; we have tested 13 different designs from 7 manufacturers (56 specimens), using the Heidelberg Valve Test Inventory with 16 subtests. Programmable valves reduce, but cannot exclude, unphysiological flow rates: even in the highest position and in combination with a standard catheter typical programmable Medos-Hakim valves allow a flow of 93–232 ml/h, Sophy SU-8-valves 86–168 ml/h with 30 cmH2O. The effect of hydrostatic valves (Hakim-Lumbar, Chhabra) can be inactivated by movements of daily life. The weight of the metal balls in most valves was too low for adequate flow reduction. Antisiphon devices are highly dependent on external, i.e. subcutaneous, pressure which has unpredictable influences on shunt function, and clinically is sometimes followed by shunt insufficiency. Two new Orbis-Sigma valves showed relatively physiological flow rates even when the vertical position (30 cmH2O) was simulated. One showed an insufficient flow (5.7 ml/h), and one was primarily obstructed. These have by far the smallest outlet of all valves. Additionally, the ruby pin tends to stick. Therefore, a high susceptibility to obliterations and blockade is unavoidable. Encouraging results obtained in pediatric patients contrast with disappointing experiences in some German and Swedish hospitals, which suggests that our laboratory findings are confirmed by clinical results. The concept of strict flow limitation seems to be inadaequate for adult patients, who need a relatively high flow during (nocturnal) ICP crises. The problem of shunt overdrainage remains unsolved.This paper is an updated version of an oral presentation held at the Consensus Conference: Hydrocephalus '92 Assisi, Italy, 26–30 April 1992Deceased 相似文献
49.
There are conflicting reports about estrogen modulating the activity of nigrostriatal dopaminergic neurons. Furthermore, modulation may be influenced by progesterone levels. Therefore, the clinical effects of sex steroids on parkinsonian symptoms in postmenopausal women with Parkinson's disease (PD) were analyzed in the present study. Patients (n = 12) were under the age of 80, able to perform the motor function tests, and showed no contraindications for estrogen suppletion. Motor function was assessed using the Unified Parkinson's Disease Rating Scale (UPDRS) and a patient interview on subjective changes. In a placebo-controlled, randomized, double-blind trial lasting 8 weeks, no significant dopaminergic effect of estradiol (E2) could be demonstrated, whereas in an open trial phase lasting 2 weeks, progesterone seemed to have an antidopaminergic effect. Several mechanisms are discussed that can account for the fact that we found no effect of E2 on motor functioning in our patients with PD. 相似文献
50.
3-Nitropropionic acid induces a spectrum of Huntington's disease-like neuropathology in rat striatum
Vis JC Verbeek MM De Waal RM Ten Donkelaar HJ Kremer HP 《Neuropathology and applied neurobiology》1999,25(6):513-521
Systemic administration of the mitochondrial toxin 3-nitropropionic acid (3-NP) to rats results in selective striatal lesions and serves as an experimental model of Huntington's disease (HD). However, the effects of the 3-NP treatment are unpredictable and result in lesions of variable severity. The present study was aimed at further characterizing the variability of the striatal lesions induced by systemic administration of 3-NP using osmotic pumps. Hematoxylin-eosin (HE) and Nissl stains as well as immunohistochemical labelling of astrocytes and striatal neurones were performed to analyse the neurotoxic effects of 3-NP. In general, chronic systemic administration of 3-NP resulted in obvious bilateral striatal lesions, which ranged from mild to severe, together with a subtle, but detectable behavioural lesion. Severe type lesions showed marked neuronal loss and an increased expression of glial fibrillary acidic protein (GFAP) in astrocytes surrounding the lesion area, whereas in the core of the lesion GFAP-immunoreactivity was absent. The mild type lesion was characterized by a substantial loss of striatal neurones and an increased expression of GFAP-positive astrocytes throughout the lesion. In a number of 3-NP-treated animals, neither type of lesion was observed, although these animals demonstrated behavioural changes in the paw test compared to controls. In the striatum of these tested 3-NP-treated animals, compromised rk' neurones were detected, suggestive of subtle and early 3-NP-induced neuronal injury. Similar dark neurones were also detected in mild and severe lesions and were immunocytochemically characterized as gamma-aminobutyric acid (GABA) and substance P containing spiny neurones, which belong to the neuronal population that is affected in early HD. These results indicate that systemic administration of 3-NP to rats may result in a spectrum of striatal pathology of which the morphology of the mild type lesion resembles the characteristic HD neuropathology most closely. 相似文献