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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
5.
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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CB. Laurell 《Scandinavian journal of clinical and laboratory investigation》2013,73(2):118-121
Observations made in an investigation of the diurnal variation of the serum iron concentration suggested that the diurnal variations of serum iron can be explained as a phenomenon secondary to the diurnal variation of the hemoglobin metabolism. This hypothesis is supported by parallel changes in the bilirubin and serum iron values. 相似文献
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Over an average span of one year, we performed a prospective clinical and immunologic evaluation of 30 patients with hemophilia. No patient developed life-threatening opportunistic infection or malignancy; however, the immunologic abnormalities and lymphadenopathy initially present in nine patients (lymphadenopathy group) persisted. In addition, five patients, representing 24% of the initial group without lymphadenopathy, developed generalized lymphadenopathy (converter group). One episode of idiopathic thrombocytopenia (ITP) and one episode of staphylococcal sepsis occurred in this "converter" group; one episode of ITP also occurred in the lymphadenopathy group. Sixteen patients remained asymptomatic. At the time of the follow-up evaluation, those differences in mononuclear cell (MNC) percentages and numbers noted initially among the three hemophiliac groups were no longer present. Natural killer cell function alone or in the presence of biologic response modifiers was not different among hemophiliac and control groups. Before developing lymphadenopathy, the converter group of patients had significantly better lymphocyte mitogenic function than did the other two groups of patients with hemophilia. However, lymphocyte mitogenic responses of all groups of patients with hemophilia significantly deteriorated over the course of the study. The abnormal mitogenic responses noted in these patients was explained in part by higher levels of spontaneous suppressor cell activity in mononuclear cell preparations from patients with hemophilia. We conclude that long-term immunologic studies of this patient population requires both quantitative and qualitative evaluations. Our data show that patients with hemophilia have progressive dysfunction of cell- mediated immunity. 相似文献
10.
In vitro characterization of the human recombinant soluble granulocyte- macrophage colony-stimulating factor receptor 总被引:1,自引:0,他引:1
We have cloned, expressed, and partially purified a naturally occurring, truncated, soluble form of the human granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor alpha subunit to investigate its biochemical and biologic properties. The soluble receptor species lacks the transmembrane and cytoplasmic domains that are presumably removed from the intact receptor cDNA by a mechanism of alternative splicing. The resulting soluble 55- to 60-kD glycosylated receptor species binds GM-CSF with a dissociation constant (kd) of 3.8 nmol/L. The soluble GM-CSF receptor successfully competes for GM-CSF binding not only with the transmembrane-anchored GM-CSF receptor alpha subunit but also with the native oligomeric high-affinity receptor complex. In addition, in human bone marrow colony-forming assays, the soluble GM-CSF receptor species can antagonize the activity of GM-CSF. Our data suggest that the soluble GM-CSF receptor may be capable of acting in vivo as a modulator of the biologic activity of GM-CSF. 相似文献