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61.
Sallam AK 《Saudi medical journal》2005,26(7):1112-1115
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Assisted hatching 总被引:1,自引:0,他引:1
Sallam HN 《Minerva ginecologica》2004,56(3):223-234
Assisted hatching entails the opening or thinning of the zona pellucida before embryo transfer in order to improve the results of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI). The technique can be performed mechanically, chemically or with a laser beam. A piezoelectric method has also been described. Meta-analyses of randomised trials have shown that assisted hatching increases the clinical pregnancy, implantation and on-going pregnancy rates in patients with poor prognosis for IVF and ICSI, particularly those with repeated implantation failure. The technique is not without risks, and has been associated with an increased incidence of monozygotic twinning. Nevertheless, it remains an invaluable tool in assisted reproductive technology. 相似文献
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Lactic acid-induced modifications in films of Eudragit RL and RS aqueous dispersions 总被引:2,自引:0,他引:2
Omari DM Sallam A Abd-Elbary A El-Samaligy M 《International journal of pharmaceutics》2004,274(1-2):85-96
Eudragit RL (ERL) and RS (ERS) are polymethacrylate co-polymers, used in film coating of sustained release dosage forms, possessing some hydrophilic properties due to the presence of quaternary ammonium groups (QAG), where ERL contains more of such groups, hence more permeable, than ERS. However, because these groups ionize in solution, they undergo electrostatic interaction with negatively charged species. This phenomenon was utilized in this study to introduce modification in the film properties of ERL and ERS by interaction with lactic acid (LA). Thermal and mechanical analyses were carried out on polymeric free films. DSC showed a shift in Tg of the film while 1H NMR spectroscopy revealed a significant deshielding in the peak of QAGs protons after interaction with LA. Stress-strain test showed an increase in three mechanical parameters of the new film (containing LA): tensile strength to modulus ratio, relative surface energy and toughness index, indicating an enhancement in the mechanical stress resistance. Tablets coated with LA-containing films showed an increase in the release rate and extent and good stability upon aging, compared to those coated with the original film. 相似文献
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OBJECTIVE: To conduct a meta-analysis of randomized controlled studies to evaluate abdominal ultrasound-guided embryo transfer compared to the clinical touch method. DESIGN: Meta-analysis. SETTING: Four studies performed in academic research centers in Barcelona, Vizcaya, Hong Kong, and Madrid. PATIENT(S): A total of 2,051 patients: 1,024 received ultrasound-guided embryo transfers and 1,027 received clinical touch method transfers. INTERVENTION(S): Fourteen studies were retrieved from the literature, but only four of them fitted our selection criteria. The meta-analysis was conducted using the RevMan software with the Peto-modified Mantel-Haenszel method and the fixed effect model. MAIN OUTCOME MEASURE(S): The primary outcome measures were the clinical pregnancy and ongoing pregnancy rates. The secondary outcome measures were the incidences of ectopic pregnancies, miscarriage rate, multiple pregnancies, and difficult transfers. RESULT(S): Compared to the clinical touch method, abdominal ultrasound-guided transfer significantly increased the clinical pregnancy rate and the ongoing pregnancy rate. There was no effect on the incidence of ectopic pregnancy, multiple pregnancy, or miscarriage rate. CONCLSUION(S): Ultrasound-guided embryo transfer increases the clinical pregnancy and ongoing pregnancy rates significantly compared to the clinical touch method. 相似文献
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BACKGROUND: Laminins (Lns) are a family of extracellular matrix glycoproteins located in the basement membrane (BM) of epithelial cells. They exist as heterotrimers composed of an alpha, beta, and gamma chain. Presently, five alpha (alpha1-5), three beta (beta1-3), and three gamma (gamma1-3) chains have been identified with different combinations of these chains resulting in 14 laminin heterotrimers thus far identified (1, 3-5). METHODS: In this study, using immunohistochemistry with chain-specific antibodies, we characterized the expression of the alpha1 (Lns-1/3), alpha3 (Lns 5,6,7), and alpha5 (Lns 10/11) chains in fetal, newborn, infant, prepubertal, and adult benign and malignant prostate glands. RESULTS: In general, alpha1 expression was higher in normal fetal prostate glands and declined by full-term birth, whereas the alpha3 and alpha5 chains remained highly expressed in the adult normal glands. In carcinoma alpha1 (Lns 1/3) and alpha5 (Lns 5,6,7) are lost, whereas alpha5 (Lns 10/11) persists. CONCLUSIONS: Alpha 1 (Lns 1/3) is prominent in BM, but is replaced by a laminin matrix rich in alpha3 (Lns 5,6,7) and alpha5 (Lns 10/11) in benign adult prostate glands. In carcinoma, both alpha1 (Lns-1/3) and alpha3 (Lns 5,6,7) are not expressed with persistence of a BM rich in alpha5 (Lns 10/11). 相似文献
70.
M?ChakravarthyEmail author V?Jawali M?Manohar TA?Patil K?Jayaprakash NV?Shivananda 《Indian Journal of Thoracic and Cardiovascular Surgery》2003,19(3):151-154
Conclusion Our case report highlights the possibility of tackling mediastinal, pericardial and pleural problems with regional anesthesia
alone even if the surgery requires opening of the pleura. 相似文献