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261.
262.
The window for embryo transfer in oocyte donation cycles depends on the duration of progesterone therapy 总被引:6,自引:3,他引:6
Prapas Y; Prapas N; Jones EE; Duleba AJ; Olive DL; Chatziparasidou A; Vlassis G 《Human reproduction (Oxford, England)》1998,13(3):720-723
In 192 oocyte donation cycles performed between January 1993 and July 1996,
we examined the width of 'the window for embryo transfer' using standard
hormonal replacement methods. All transfers were performed within 48 h of
insemination. We varied the day of embryo transfer with regard to the
initiation of progesterone therapy and, thus, the duration of endometrial
exposure to progesterone and analysed the resulting pregnancy rates.
Patients were divided into five groups (I-V) and embryo transfers were
performed 2, 3, 4, 5 or 6 days following initiation of progesterone
therapy. The number of pregnancies per transfer cycle achieved in groups
I-V were 0 (0%), 3 (12%), 16 (40%), 29 (48.3%), and 10 (20.4%)
respectively. The increased pregnancy rate in group III in comparison to
group II is statistically significant (P < 0.03). Furthermore, the
pregnancy rate in group IV (5 days of progesterone administration before
embryo transfer) was significantly higher than in group V (6 days of
progesterone administration before embryo transfer; P < 0.005). We also
noted that, when embryos were transferred 4 or 5 days after initiation of
progesterone therapy, the pregnancy rates were not significantly different
between menopausal and cycling recipients (50% vs 43.7%). Our results
indicate that the window for embryo transfer is dependent on duration of
treatment with progesterone; it begins approximately 48 h after starting
progesterone administration and lasts for approximately 4 days. The optimum
period for transferring embryos at the 4- to 8-cell stage corresponds to
cycle days 18 and 19. Transfers performed on the 17th and 20th days of the
cycle can result in successful implantation, although the rates of
implantation are highest when transfers are done on days 18 and 19.
相似文献
263.
S. Levidiotou G. Vrioni H. Papadogeorgaki K. Avdeliodi H. Kada G. Kaparos E. Kouskouni E. Fragouli N. J. Legakis 《European journal of clinical microbiology & infectious diseases》2005,24(3):207-213
The present retrospective study was initiated to determine the prevalence of Chlamydia trachomatis and to assess the risk factors for infection in adult women and men presenting to general practitioners, gynecologists, dermatologists, and family-planning centers in Greece. The study was carried out in four different Greek hospital centers using highly sensitive nucleic acid amplification techniques. Altogether, 16,834 women and 1,035 men were enrolled from October 1998 to April 2004. Two types of specimens were collected from each patient: cervical swabs from women, urethral swabs from men, and first-catch urine from women and men. All specimens were examined with the Cobas Amplicor C. trachomatis polymerase chain reaction assay (Roche Molecular Systems, Branchburg, NJ, USA) or the LC × C. trachomatis ligase chain reaction assay (Abbott Laboratories, Abbott Park, IL, USA). Demographic and behavioral data were collected by clinicians using a standardized questionnaire. A total of 704 (3.9%) patients were infected with C. trachomatis. The prevalence among female patients was 3.5% and that among male patients 11.2%. Among infected patients, 88% were under 30 years of age, 71% reported more than one sexual partner, and 91% reported a new sexual partner within the last year. In conclusion, the prevalence of C. trachomatis infection in Greece is low. Young age and new and multiple sexual partners within the last year were factors consistently associated with an increased risk of chlamydial infection. 相似文献
264.
Brito FS Caixeta AM Rati MA Perin MA Martinez Filho EE Ramires JA 《The Journal of invasive cardiology》1998,10(3):162-168
Excimer laser coronary angioplasty (ELCA) is a useful technique for the treatment of selected complex coronary lesions. However, this technology has been limited by significant restenosis and, to date, predictors of restenosis after use of this device are not clearly defined. In order to determine predictors of restenosis after ELCA, 43 lesions presenting with restenosis (> 50% diameter stenosis) at angiographic follow-up were compared to 46 lesions without restenosis, based on patient-related, qualitative and quantitative angiographic parameters. Univariate analysis revealed 9 variables with at least a borderline (p < 0.15) significant relation to restenosis: (1) age (p = 0.0759), (2) proximal left anterior descending site (p = 0.074), (3) presence of a restenotic lesion (p = 0.104), (4) lesion length (p = 0.0034), (5) reference diameter of the treated vessel (p = 0.0076), (6) post laser minimal luminal diameter (MLD) (p = 0.1160), (7) post-procedural MLD (p = 0.0001), (8) post-procedural stenosis (p = 0.0250) and (9) total procedural gain (p = 0.0051). After entering stepwise logistic regression analysis, only 3 variables emerged as independent predictors of restenosis: treatment of a restenotic lesion (p = 0.0255), lesion length (p = 0.0291) and post-procedural MLD (p = 0.0007). Based on these data, we conclude that post-procedural MLD is the most important predictor of restenosis after ELCA. Lesion length and the treatment of restenotic lesions are also independently associated with an increased risk of restenosis after ELCA. Therefore, achieving the best possible luminal result at the time of the first intervention should be the goal of the procedure, especially when treating high restenosis risk lesions. 相似文献
265.
266.
The common 'thermolabile' variant of methylene tetrahydrofolate reductase is a major determinant of mild hyperhomocysteinaemia 总被引:11,自引:0,他引:11
Harmon DL; Woodside JV; Yarnell JW; McMaster D; Young IS; McCrum EE; Gey KF; Whitehead AS; Evans AE 《QJM : monthly journal of the Association of Physicians》1996,89(8):571-577
Mild hyperhomocysteinaemia is a major risk factor for vascular disease and
neural tube defects (NTDs), conferring an approximately three-fold relative
risk for each condition. It has several possible causes: heterozygosity for
rare loss of function mutations in the genes for 5,10-methylene
tetrahydrofolate reductase (MTHFR) or cystathionine-&bgr;-synthase
(CBS); dietary insufficiency of vitamin co-factors B6, B12 or folates; or
homozygosity for a common 'thermolabile' mutation in the MTHFR gene which
has also been associated with vascular disease and NTDs. We quantified the
contribution of the thermolabile mutation to the hyperhomocysteinaemic
phenotype in a working male population (625 individuals). Serum folate and
vitamin B12 concentrations were also measured and their relationship with
homocysteine status and MTHFR genotype assessed. The homozygous
thermolabile genotype occurred in 48.4, 35.5, and 23.4% for the top 5, 10
and 20% of individuals repectively) ranked by plasma homocysteine levels,
compared with a frequency of 11.5% in the study population as a whole
establishing that the mutation is a major determinant of homocystein levels
at the upper end of the range. Serum folate concentrations also varied with
genotype, being lowest in thermolabile homozygotes. The MTHFR thermolabile
genotype should be considered when population studies are designed to
determine the effective homocysteine-lowering dose of dietary folate
supplements, and when prophylactic doses of folate are recommended for
individuals.
相似文献
267.
Mystakidou K Befon S Hondros K Kouskouni E Vlahos L 《Journal of pain and symptom management》1999,18(5):323-330
This prospective nonrandomized trial was performed to evaluate the efficacy of salmon calcitonin (sCT) in controlling pain related to bone metastasis in cancer patients and the relation of sCT's analgesic efficacy with beta-endorphin blood levels. The study group consisted of 22 cancer patients with bone metastases (male 13 and female 9, age range 38-77 years). Pain control was first achieved by continuous subcutaneous (s.c.) morphine administration. The next increase in pain was managed with continuous s.c. administration of 400 IU/day sCT. Beta-endorphin blood levels were measured before and during sCT administration. The first measurement was taken before sCT administration; subsequent measurement occurred at 12, 24, and 48 hours and 7 days after the commencement of treatment. Pain scores were monitored by a visual analogue scale. A complete blood count and a biochemical screening profile were taken before the administration of calcitonin and also on the seventh and the fifteenth day of the administration. The results showed a satisfactory analgesic effect. The mean pain score before the calcitonin administration was 4.43 and the score on the seventh day was 1.17. The gradual reduction of pain score was associated with an increase in beta-endorphin blood levels (increase to 147.2% of baseline on the seventh treatment day). In three cases, no satisfactory analgesic effect was obtained and pain control was achieved by increasing the continuous s.c. morphine dosage. No significant side effects were observed. These data suggest that sCT in high doses may be a useful adjuvant analgesic when combined with low doses of morphine in continuous s.c. administration for the management of metastatic bone pain. 相似文献
268.
269.