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This study involving 500 edentulous patients (250 males, 250 females) was undertaken to introduce a dimensionless factor termed the "palatal height ratio," defined as the ratio of the width of the edentulous maxillary arch to the height of the palate. The authors categorized the height, width, and anteroposterior dimensions of the edentulous maxillae. Measurements were made on diagnostic casts at five defined points. The difference between males and females was statistically analyzed and the variables were categorized. The results of this study may be helpful for a better standardization of the same variables in future studies. 相似文献
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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
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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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Remzi?AvciEmail author Berkant?Kaderli Berrin?Avci Saban?Simsek Mehmet?Baykara Zeynep?Kahveci Oner?Gelisken Ahmet?Ali?Yucel 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2004,242(10):845-852
Background To evaluate the results of pars plana vitrectomy with peeling of the internal limiting membrane (ILM) in eyes with chronic macular oedema.Methods PPV with indocyanine green (ICG) assisted peeling of the ILM was performed in 33 eyes with diabetic (21 eyes) or non-diabetic (12 eyes) macular oedema. Postoperatively, resolution of macular oedema, improvement of visual acuity (VA) and complications were documented. The peeled membranes were submitted for light and transmission electron microscopic evaluation.Results The mean follow-up time was 12.2 months. The macular oedema decreased or was resolved in 17 (81%) eyes in the diabetic group and in 11 (92%) eyes in the non-diabetic group. VA improved by at least 2 lines in 11 (52%) eyes in the diabetic group and in 7 (58%) eyes in the non-diabetic group. The difference between visual acuity improvements of the two groups was not statistically significant (P>0.05). However, in the diabetic group the difference of visual improvement between cystoid and diffuse type of macular oedema eyes was statistically significant (14% versus 71%, P=0.02). Light and transmission electron microscopy showed the presence of ILM in all specimens. During the follow-up period no recurrence of macular oedema or epiretinal membrane formation was observed.Conclusion Pars plana vitrectomy with peeling of the ILM and epiretinal membrane leads to the resolution of macular oedema in the majority of eyes. This however, is not always associated with VA improvement. In diabetic eyes, cystoid type of macular oedema appears to be a poor prognostic factor for improved VA. 相似文献