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31.
In this study, we have used time-lapse video cinematography to study fertilization in 50 human oocytes that had undergone intracytoplasmic sperm injection (ICSI). Time-lapse recording commenced shortly after ICSI and proceeded for 17-20 h. Oocytes were cultured in an environmental chamber which was maintained under standard culture conditions. Overall, 38 oocytes (76%) were fertilized normally, and the fertilization rate and embryo quality were not significantly different from 487 sibling oocytes cultured in a conventional incubator. Normal fertilization followed a defined course of events, although the timing of these events varied markedly between oocytes. In 35 of the 38 fertilized oocytes (92%), there were circular waves of granulation within the ooplasm which had a periodicity of 20-53 min. The sperm head decondensed during this granulation phase. The second polar body was then extruded, and this was followed by the central formation of the male pronucleus. The female pronucleus formed in the cytoplasm adjacent to the second polar body at the same time as, or slightly after, the male pronucleus, and was subsequently drawn towards the male pronucleus until the two abutted. Both pronuclei then increased in size, the nucleoli moved around within the pronuclei and some nucleoli coalesced. During pronuclear growth, the organelles contracted from the cortex towards the centre of the oocyte, leaving a clear cortical zone. The oocyte decreased in diameter from 112 to 106 microm (P < 0.0001) during the course of the observation period. The female pronucleus was significantly smaller in diameter than the male pronucleus (24.1 and 22.4 microm respectively, P = 0.008) and contained fewer nucleoli (4.2 and 7.0 respectively, P < 0.0001). After time-lapse recording, oocytes were cultured for 48 h prior to embryo transfer or cryopreservation. Embryo quality was related to fertilization events and periodicity of the cytoplasmic wave, and it was found that good quality embryos arose from oocytes that had more uniform timing from injection to pronuclear abuttal and tended to have a longer cytoplasmic wave. In conclusion, we have shown that time-lapse video cinematography is an excellent tool for studying fertilization and early embryo development, and have demonstrated that human fertilization comprises numerous complex dynamic events.   相似文献   
32.
BACKGROUND: Some cases of recurrent miscarriage have a thrombotic basis. Thromboelastography is a rapid, reproducible test of whole-blood haemostasis. METHODS: Thromboelastography was performed in 494 consecutive, non-pregnant women (median age 35 years; range 21-48) with a history of miscarriages at <12 weeks gestation (median 4; range 3-12) and 55 parous women (median age 33 years; range 20-41) with no history of pregnancy loss. The prospective outcome of untreated pregnancies amongst 108 women with recurrent miscarriage was studied. RESULTS: The maximum clot amplitude (MA) (median 66.0 mm; range 48.0-76.0) was significantly higher and the rate of clot lysis (LY30) (median 2.5%; range 0.5-7.8) significantly lower amongst women with recurrent miscarriage compared with controls (MA 61.5 mm; range 50.0-67.0; P = 0.01; LY30 4.9%; range 2.9-9.7; P = 0.01). The pre-pregnancy MA was significantly higher amongst women who subsequently miscarried (median 66.0 mm; range 54.0-73.0) compared with those whose had a live birth (median 61.7 mm; 48.0-71.5; P < 0.01). A pre-pregnancy MA >or=64 mm has a sensitivity of 68% and specificity of 82% to predict miscarriage. CONCLUSIONS: Thromboelastography identifies a subgroup of women with recurrent miscarriage to be in a prothrombotic state outside of pregnancy. Women in such a state are at increased risk of miscarriage in future untreated pregnancies.  相似文献   
33.
Umbilical cord blood screening for cytomegalovirus DNA by quantitative PCR.   总被引:1,自引:0,他引:1  
BACKGROUND: Cytomegalovirus (CMV) infection, which is the most common congenitally transmitted infection, affects approximately 1% of neonates worldwide. Despite its prevalence, no convenient screening test for neonatal CMV infection has been implemented. OBJECTIVE: The purpose of this pilot study was to evaluate the feasibility and yield of screening umbilical cord blood for CMV DNA emiaby quantitative PCR. STUDY DESIGN: Umbilical cord blood was tested for CMV DNAemia using a commercial quantitative PCR assay. Maternal CMV serostatus at the time of delivery was assessed by testing for CMV IgG and IgM antibodies in serum. CONCLUSIONS: Screening for congenital CMV infection with PCR is easily incorporated into routine labor and delivery care using discarded cord blood specimens to identify neonates whose infection is otherwise undiagnosed. Among 433 infants tested, two (0.5%) had DNAemia detected in cord blood, one of whom was symptomatic, and both of whose mothers were CMV IgG positive and IgM negative. Viremic neonates identified by screening with PCR may be at high risk of developing long-term neurological complications of CMV infection and cannot reliably be identified using clinical presentation or maternal serology. Because of its convenience, cord blood CMV screening with PCR should be further investigated for incorporation into neonatal screening protocols.  相似文献   
34.
A postal survey of 200 General Practitioners in south Dublin was undertaken. The aim was to elicit information about the problems experienced by GPs when caring for terminally ill cancer patients at home, and about their perceived needs for both further training and support services. All respondents experienced problems at least occasionally with control of pain and other symptoms. 25% of GPs surveyed frequently experienced difficulty with access to hospice in-patient beds, and with inadequate home support services. Overall, satisfaction with specialist Palliative Care Services was high. The majority of GPs felt that they would benefit from further education in Palliative Medicine. They also nominated ways to help them improve care of terminally ill patients at home including further training in pain control and symptom relief, more general and specialist nursing support, and more specialist medical support in the community.  相似文献   
35.
The aim of this study was to determine whether bacterial vaginosis(BV) is associated with a history of recurrent pregnancy loss.A total of 500 consecutive patients attending the RecurrentMiscarriage Clinic were screened for the presence of BV. Inwomen who had had at least one late miscarriage BV was foundtwice as commonly (27/130; 21%) as in women who had had onlyearly losses (31/370; 8%) (P<0.001). The difference was evenlarger (26 versus 8%) if women who had had term pregnancieswere excluded. Moreover, BV was found three times more commonlyin Afro-Caribbean women [17 (29%) of 58] than in Caucasian women[36 (9%) of 379] and, in both groups of women, BV was diagnosedat least twice as frequently in those with a history of at leastone late miscarriage than in those who had experienced firsttrimester pregnancy losses only (P<0.001). The conditionoccurred twice as often among smokers than non-smokers and,in both groups, it was at least twice as common in women witha history of at least one late miscarriage as in those who hadhad early pregnancy losses only (P<0.001). However, the relationshipbetween BV and smoking was independent of ethnic origin. Womenwho douched with chloroxylenol were mostly Afro-Caribbean andhad BV more than twice as often as women who did not douche.  相似文献   
36.
Recent studies by others have shown that the endonuclease complexcoded for by the uvrA, uvrB and uvrC genes of Escherichia coli(UVR ABC excision nuclease) can incise DNA containing a varietyof ‘bulky-type’ lesions, such as those resultingfrom u.v. light, (±)-7, 8ß-dihydroxy-9, 10-epoxy-7,8, 9, 10-tetrahydrobenzo[a]pyrene (anti-BPDE), and N-acetoxy-2-acetylaminofluorene.Using partially purified UVR ABC excision nuclease, we havequantitated the number of endonuclease sensitive sites (ESS)in purified DNA isolated from human fibroblasts treated withu.v. light or BPDE. The number of ESS/108 daltons of DNA werecalculated from the number average mol. wt. of the DNA as determinedby sedimentation in alkaline sucrose gradients. The number ofendonuclease sites increased linearly with increasing dosesof either u.v. light or BPDE. The UVR ABC excision nucleasewas able to incise a majority of the BPDE-DNA adducts. Xerodermapigmentosum fibroblasts, complementation group A (XP12BE) had20–25% more ESS at each dose than the BPDE-treated normal(HSBP) cells. Cells treated with 4 µM BPDE and allowed12 h of incubation to perform excision repair showed removalof 60% of the initial number of ESS from HSBP DNA and 40% ofthe ESS from XP-A DNA. Beyond 12 h XP12BE cells lost no additionalESS while HSBP cells continued to lose ESS, athough at a slowerrate, until at 48 h only 22% of the initial ESS remained. Incells treated with 10 J/m2 of u.v. light, the UVR ABC excisionnuclease detected 60% of the sites recognized by the pyridiminedimer specific Micrococcus luteus glycosylase/apyrimidinic endonuclease.These results demonstrate the potential use of the UVR ABC excisionnuclease in a quantitative assay for determining the numberof carcinogen-induced lesions in human DNA.  相似文献   
37.
38.
BACKGROUND: Some cases of recurrent miscarriage and later pregnancy complications have a thrombotic basis. Factor V Leiden is a common thrombophilic mutation. METHODS: The prospective outcome of untreated pregnancies amongst 25 women heterozygous for the Factor V Leiden allele who had a history of either recurrent early miscarriages only (three or more miscarriages at <12 weeks gestation; n = 19) or of late miscarriage (>12 weeks gestation; n = 9) was studied. Control groups of women with a similar pregnancy history but who had a normal Factor V genotype were also studied. RESULTS: The live birth rate was significantly lower amongst women with a history of recurrent early miscarriage who carried the Factor V Leiden allele (6/16; 37.5%) compared with that amongst those with a normal Factor V genotype (106/153; 69.3%; odds ratio 3.75, 95% confidence intervals 1.3-10.9). The live birth rate was 11.1% (1/9) amongst those with a history of late miscarriage carrying the Factor V Leiden allele and 48.9% (22/45) amongst those with a normal Factor V genotype. CONCLUSIONS: Attention should be directed at screening women with recurrent miscarriage associated with placental thrombosis for Factor V Leiden and a policy of targeted thromboprophylaxis during future pregnancies should be assessed in the form of a randomized controlled trial.  相似文献   
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40.
This article reports on the Ohio Quality Assurance Project, a two year demonstration. The project developed a model quality assurance system for in-home supportive services funded by Title III of the Older Americans Act including home health aide, personal care, homemaker, transportation and escort, home delivered meals, chore and home maintenance services. Using four planning and service areas in the state of Ohio comprising over 40 countries, the project developed, implemented and evaluated quality assurance standards and monitoring activities for Older Americans Act services. In addition, a second part of the project included in-depth case studies with consumers receiving in-home care.  相似文献   
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