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1.
Aim: Our aim was to compare the outcome in subsequent frozen embryo replacement cycles in four groups of patients who had elective cryopreservation of all their embryos because they were considered to be at increased risk of developing severe ovarian hyperstimulation syndrome. Design: Sixty-two (91%) of 68 IVF cycles (68 patients) in which elective cryopreservation of all embryos was performed were analyzed. All patients continued on the GnRH agonist, buserelin, after oocyte recovery until the onset of vaginal bleeding. Frozen embryo replacement occurred in a hormone replacement cycle that started either on day 3 of the withdrawal bleed (group I;N=15) or after serum estradiol levels had fallen to <100 pmol/L (group II;N=16). The other patients commenced a frozen embryo replacement cycle several months later in either a hormone replacement (group III;N=15) or a natural (group IV;N=16) cycle. Results: Two patients developed severe ovarian hyperstimulation syndrome. There were no significant differences among the four groups regarding demographic variables, the dose of hMG used, and the clinical outcome. There was a higher but not significantly different clinical pregnancy rate in group I (26.7%), compared to group II (12.5%), group III (13.3%), and group IV (18.8%). Conclusions: Several options exist for the timing and protocol used for frozen embryo replacement in patients who had elective cryopreservation for the prevention of ovarian hyperstimulation syndrome, none of which was found to be clearly superior in this observational report.Presented at the 1994 Annual Conference of the American Fertility Society.  相似文献   
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The ability to sense orientation relative to gravity requires dense particles, called otoconia, which are localized in the vestibular macular organs. In mammals, otoconia are composed of proteins (otoconins) and calcium carbonate crystals in a calcite lattice. Little is known about the mechanisms that regulate otoconial biosynthesis. To begin to elucidate these mechanisms, we have partially sequenced and cloned the major protein component of murine otoconia, otoconin-90 (OC90). The amino acid sequence identified an orphan chimeric human cDNA. Because of its similarity to secretory phospholipase A2 (sPLA2), this gene was referred to as PLA2-like (PLA2L) and enabled the identification of human Oc90. Partial murine cDNA and genomic clones were isolated and shown to be specifically expressed in the developing mouse otocyst. The mature mouse OC90 is composed of 453 residues and contains two domains homologous to sPLA2. The cloning of Oc90 will allow an examination of the role of this protein in otoconial biosynthesis and in diseases that affect the vestibular system.  相似文献   
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The maternal mortality rate in the Third World remains high despite the launch of the Safe Motherhood Initiative (SMI) in 1987. There are various sociocultural, political and economic factors which play a major role in this. The five main causes of maternal mortality are haemorrhage, sepsis, unsafe abortion, hypertensive disorders and obstructed labour. The key to safe motherhood lies in providing quality maternity care for all women. It is important to know the nature and the extent of the problems in the community so that appropriate technology can be introduced with optimum utilization of the available resources. The different ways of achieving safe motherhood are discussed with emphasis on community based interventions. The SMI goals can be reached provided the Safe Motherhood programmes are well funded, the community workers well trained and the leaders of the community and the nation dedicated.  相似文献   
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Electrocardiographic (ECG) artifacts resulting from misplacements of electrodes are frequent, difficult to detect, and can become of clinical importance. We investigated 2 healthy volunteers and 3 patients with ECG signs of inferior myocardial scars. We exchanged the peripheral electrodes in a defined manner and investigated the resulting ECG for morphology and possible diagnostic errors. In the volunteers, ECG signs of inferior ischemia could be produced. In the patients with ischemic heart disease, normal ECG without signs of ischemia resulted by placing the electrode of the left leg to the left arm. The automatic ECG analyzer was not helpful in detecting artifacts by misplaced electrodes. A very low amplitude of the QRS complex in lead I, II, or III was pathognomonic for electrode misplacement in half of the cases. ECG artifacts must also be suspected when abnormal QRS- or P-axis occur or when QRS morphology does not match with the clinical presentation of the patient.  相似文献   
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Aim: Activation of muscarinic receptors on the detrusor smooth muscle is followed by contraction, which involves both myosin light chain kinase (MLCK) and Rho kinase (ROCK). The aim of this study was to determine the relative contributions of MLCK and ROCK to carbachol-induced contraction of human detrusor smooth muscle in vitro.
Methods: Detrusor smooth muscle strips were prepared from the macroscopically unaffected bladder wall of patients underwent cystectomy. The strips were fixed in an organ bath, and carbachol or KCl-induced isometric contractions were measured by force transducers.

Results: Addition of carbachol (0.4-4 μmol/L) into the bath induced concentration-dependent contractions of detrusor specimens, which was completely abolished by atropine (1 μmol/L). Pre-incubation of detrusor specimens with either the MLCK inhibitor ML-9 or the ROCK inhibitors HA1100 and Y-27632 (each at 10 μmol/L) significantly blocked carbachol-induced contractions as compared to the time-control experiments. Moreover, MLCK and ROCK inhibition were equally effective in reducing carbachol-induced contractions. The residual carbachol-induced contractions in the presence of both MLCK and ROCK inhibitors were significantly smaller than the contractions obtained when only one enzyme (either MLCK or ROCK) was inhibited, suggesting an additive effect of the two kinases. Interestingly, ROCK-mediated carbachol-induced contractions were positively correlated to the age of patients (r=0.52, P〈0.05).

Conclusion: Both MLCK and ROCK contribute to carbachol-induced contractions of human detrusor smooth muscle. ROCK inhibitors may be a new pharmacological approach to modulate human bladder hyperactivity.  相似文献   
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Background

For women who have a caesarean section in their preceding pregnancy, two care policies for birth are considered standard: planned vaginal birth and planned elective repeat caesarean. Currently available information about the benefits and harms of both forms of care are derived from retrospective and prospective cohort studies. There have been no randomised trials, and recognising the deficiencies in the literature, there have been calls for methodologically rigorous studies to assess maternal and infant health outcomes associated with both care policies. The aims of our study are to assess in women with a previous caesarean birth, who are eligible in the subsequent pregnancy for a vaginal birth, whether a policy of planned vaginal birth after caesarean compared with a policy of planned repeat caesarean affects the risk of serious complications for the woman and her infant.

Methods/Design

Design: Multicentred patient preference study and a randomised clinical trial. Inclusion Criteria: Women with a single prior caesarean presenting in their next pregnancy with a single, live fetus in cephalic presentation, who have reached 37 weeks gestation, and who do not have a contraindication to a planned VBAC. Trial Entry & Randomisation: Eligible women will be given an information sheet during pregnancy, and will be recruited to the study from 37 weeks gestation after an obstetrician has confirmed eligibility for a planned vaginal birth. Written informed consent will be obtained. Women who consent to the patient preference study will be allocated their preference for either planned VBAC or planned, elective repeat caesarean. Women who consent to the randomised trial will be randomly allocated to either the planned vaginal birth after caesarean or planned elective repeat caesarean group. Treatment Groups: Women in the planned vaginal birth group will await spontaneous onset of labour whilst appropriate. Women in the elective repeat caesarean group will have this scheduled for between 38 and 40 weeks. Primary Study Outcome: Serious adverse infant outcome (death or serious morbidity). Sample Size: 2314 women in the patient preference study to show a difference in adverse neonatal outcome from 1.6% to 3.6% (p = 0.05, 80% power).

Clinical Trial Registration

ISCTRN5397431  相似文献   
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This paper delineates important considerations for having a better understanding of quality in maternity care. High quality requires providing a minimum level of care to all pregnant women and their new born babies and a higher level of care to those who need it; obtaining the best possible medical outcome of mother and baby; providing care which satisfies users and providers; and maintaining sound managerial and financial performance. While all these aspects are important, prioritizing among interventions to improve them will be influenced by cultural values, expectations and available resources.  相似文献   
10.
Histologic grading systems are used to guide diagnosis, therapy, and audit on an international basis. The reproducibility of grading systems is usually tested within small groups of pathologists who have previously worked or trained together. This may underestimate the international variation of scoring systems. We therefore evaluated the reproducibility of an established system, the Banff classification of renal allograft pathology, throughout Europe. We also sought to improve reproducibility by providing individual feedback after each of 14 small groups of cases. Kappa values for all features studied were lower than any previously published, confirming that international variation is greater than interobserver variation as previously assessed. A prolonged attempt to improve reproducibility, using numeric or graphical feedback, failed to produce any detectable improvement. We then asked participants to grade selected photographs, to eliminate variation induced by pathologists viewing different areas of the slide. This produced improved kappa values only for some features. Improvement was influenced by the nature of the grade definitions. Definitions based on "area affected" by a process were not improved. The results indicate the danger of basing decisions on grading systems that may be applied very differently in different institutions.  相似文献   
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