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11.
Comparison of ultrasonographic findings in spontaneous abortions with normal and abnormal karyotypes 总被引:2,自引:2,他引:2
To determine whether ultrasonographic findings can predict the karyotype of
spontaneous abortions, 137 pregnancies (54 spontaneous, 83 assisted
ovulatory cycles) that subsequently aborted and had chromosome analysis
performed on the products of conception were studied ultrasonographically.
Transvaginal ultrasound was performed using an Acuson 128XP/10 with 7.5 MHz
probe. The numbers of empty gestational sacs, small and normal for
gestational size, embryonic poles and embryos with documented cardiac
activity were calculated. The frequency of each of these findings in
pregnancies with normal and abnormal karyotypes was compared. Of the 137
spontaneous abortions, 51 had normal chromosome analyses and 86 had
abnormal karyotypes (68 aneuploidies and 18 polyploidies). Ultrasonographic
findings in the 51 karyotypically normal pregnancies included 16 (31%) with
empty gestational sacs, and 35 (69%) with embryonic poles, of which 24
(69%) were at least 1 week smaller than expected for gestational age and 11
(31%) were the expected size. Embryonic cardiac activity was documented in
22 (63%) of the 35 embryonic poles. Amongst 86 pregnancies with abnormal
karyotypes, similar frequencies of ultrasound findings were found: 23 (27%)
with empty gestational sacs, 42 (67%) with embryonic poles smaller than
expected for gestational age, and 50 (79%) embryos lost after documentation
of embryonic cardiac activity. No differences in the frequency of
ultrasonographic findings of empty gestational sacs, small embryonic pole
and embryonic cardiac activity were observed between karyotypically normal
and abnormal spontaneous abortions. Ultrasonographic findings cannot
predict the karyotype of spontaneous abortions.
相似文献
12.
Gonadotrophin-releasing hormone agonist dose-dependency of pituitary desensitization during controlled ovarian hyperstimulation in IVF 总被引:2,自引:2,他引:2
Janssens RM; Vermeiden JP; Lambalk CB; Schats R; Schoemaker J 《Human reproduction (Oxford, England)》1998,13(9):2386-2391
The aim of this study was to find the minimal effective daily s.c. dose of
the gonadotrophin-releasing hormone (GnRH) agonist, triptorelin acetate,
that suppresses the GnRH-induced release of luteinizing hormone (LH) at
time of human chorionic gonadotrophin (HCG) injection and thereby prevents
spontaneous LH surges during in-vitro fertilization (IVF) stimulation
cycles. Therefore, a double-blind, prospective and randomized titration
study was performed. A total of 48 IVF patients were divided into four
groups of 12 patients. Each group received a different dose of triptorelin
acetate, namely 5, 15, 50 or 100 microg s.c. daily. Standard ovarian
stimulation was carried out using urinary follicle stimulating hormone
(FSH) preparations. A 500 microg GnRH test was performed 90 min before the
HCG injection in order to measure the degree of pituitary desensitization.
Spontaneous LH surges were not detected in any of the groups, although
three patients in the 5 microg group had ovulated at the time of ovum
retrieval. The pituitary LH response to the GnRH test at time of HCG,
expressed as area under the curve (AUC), appeared to be dose-dependent.
Thus, a daily s.c. dose of 100 microg triptorelin acetate appears to be too
high, since adequate desensitization of the pituitary (i.e. no spontaneous
LH surge) can be achieved with doses as low as 15 and 50 microg.
相似文献
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Wood BR Huddleston K Kolm P 《Neonatal intensive care : the journal of perinatology-neonatology》1993,6(3):20-22
Delivery of medications by some infusion devices is irregular. This study investigated instantaneous flow in several infusion devices set at a rate of 1 ml/hr. The following devices were tested: Infusion Pumps: IMED 956A, IVAC 570, IVION "Kids Pump." Syringe Pumps: Medfusion, Baxter, Baxter OR. Tests were performed using a Bio-Tek Infusion Device Analyzer (Model IDA-1). Instantaneous flow rate was defined as Q1/T1 where: Q=sample volume and T=time required to deliver sample volume. The infusion devices were received directly from their respective manufacturers and had not seen clinical service before testing. The units were fully charged and were tested while on AC power. The tests were conducted by the authors, using standard infusion sets and commercially prepared 5% dextrose and 0.45% sodium chloride solution. Each pump was tested for several hours and multiple trials were performed on each pump. The infusion pumps, IMED, IVION, and IVAC all demonstrated deviations from the desired flow rate. The IVAC pump had a greater fluctuation in flow from the set value of 1 ml/hr (p less than 0.02). Variances from mean +/- standard error for each device are shown in parenthesis. IMED 965A (0.005+/-0.014), IVION Kid's Pump (0.002+/-0.009), IVAC 570 (0.001+/-0.006). The Baxter syringe pump (0.002+/-0.009) also had a wide variance in flow. The Baxter OR (0.001+/-0.005) and the Medfusion (0.001+/-0.008) syringe pumps maintained the most consistent flow and showed less variance than the other devices tested.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Women with polycystic ovary syndrome demonstrate worsening markers of cardiovascular risk over the short‐term despite declining hyperandrogenaemia: Results of a longitudinal study with community controls
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18.
Muge Capan Julie S. Ivy James R. Wilson Jeanne M. Huddleston 《Health care management science》2017,20(2):187-206
The primary cause of preventable death in many hospitals is the failure to recognize and/or rescue patients from acute physiologic deterioration (APD). APD affects all hospitalized patients, potentially causing cardiac arrest and death. Identifying APD is difficult, and response timing is critical - delays in response represent a significant and modifiable patient safety issue. Hospitals have instituted rapid response systems or teams (RRT) to provide timely critical care for APD, with thresholds that trigger the involvement of critical care expertise. The National Early Warning Score (NEWS) was developed to define these thresholds. However, current triggers are inconsistent and ignore patient-specific factors. Further, acute care is delivered by providers with different clinical experience, resulting in quality-of-care variation. This article documents a semi-Markov decision process model of APD that incorporates patient and provider heterogeneity. The model allows for stochastically changing health states, while determining patient subpopulation-specific RRT-activation thresholds. The objective function minimizes the total time associated with patient deterioration and stabilization; and the relative values of nursing and RRT times can be modified. A case study from January 2011 to December 2012 identified six subpopulations. RRT activation was optimal for patients in “slightly concerning” health states (NEWS?>?0) for all subpopulations, except surgical patients with low risk of deterioration for whom RRT was activated in “concerning” states (NEWS?>?4). Clustering methods identified provider clusters considering RRT-activation preferences and estimation of stabilization-related resource needs. Providers with conservative resource estimates preferred waiting over activating RRT. This study provides simple practical rules for personalized acute care delivery. 相似文献
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