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11.
Male genital tract obstructions may result from infections, previous inguinal and scrotal surgery (vasectomy) and congenital bilateral absence of the vas deferens (CBAVD). Microsurgery can sometimes be successful in treating the obstruction. In other cases and in cases of failed surgical intervention, the patient can be treated by microsurgical or percutaneous epididymal sperm aspiration (MESA, PESA) or testicular sperm extraction (TESE) and intracytoplasmic sperm injection (ICSI). We present the results of 39 ICSI procedures for obstructive azoospermia in 24 couples. The aetiology of the obstruction was failed microsurgery in 11 patients, CBAVD in nine and genital infections in four. Sperm retrieval was accomplished via MESA in four cases, PESA in 18 cases and via TESE in 11 cases. TESE was only applied when PESA failed to produce enough spermatozoa for simultaneous ICSI. In six patients, the ICSI procedure was performed with cryopreserved spermatozoa after an initial PESA procedure. Fertilization occurred in 47% of the metaphase II oocytes; embryo transfer was performed in 92% of procedures and resulted in a clinical pregnancy in 13/39 procedures. Ongoing pregnancy was achieved in 10/39 procedures. One pregnancy was terminated early after prenatal investigation showed a cytogenetic abnormality (47,XX+18, Edwards syndrome). The other nine pregnancies resulted in the live birth of 10 children, without any congenital abnormalities. Epididymal and testicular retrieved spermatozoa were successfully used for ICSI to treat obstructive azoospermia, and resulted in an ongoing pregnancy in 10 of 24 couples (41.6%) after 39 ICSI procedures, a success rate of 25.6% per treatment cycle and of 27.7% per embryo transfer.   相似文献   
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Five carbapenem-resistant Acinetobacter baumannii isolates, collected from the United Arab Emirates in 2006, were investigated to identify the mechanism(s) responsible for carbapenem resistance. Genotyping was performed by pulsed-field gel electrophoresis, and the location of the bla OXA-23 gene was determined by using the endonuclease I Ceu I technique and mating-out assays. The four isolates in which the bla OXA-23 gene was located on the chromosome within a Tn 2006 composite transposon were clonally related. The single non-clonally related isolate harboured the bla OXA-23 gene on a 70-kb transferable plasmid. This study reports on the dissemination of OXA-23-producing A. baumannii isolates in the Middle East.  相似文献   
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The spread of the plasmid-mediated carbapenem-hydrolyzing oxacillinase OXA-58 was detected in Acinetobacter sp. clinical isolates from southern Europe, the Balkans, and central Turkey. It may contribute significantly to the emergence of carbapenem resistance in Acinetobacter spp., at least in this part of the world.  相似文献   
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Summary Mesulergine, an 8--aminoergoline, is now proven to be of utility in the clinic as an antiparkinsonian drug. However, the molecule itself showsin vitro andin vivo antidopaminergic properties. Mesulergine is rapidly metabolized into several pharmacologically active DA agonists. The influence of mesulergine on central DA metabolism in rats is dependent on the route of drug administration. It was possible to determine the different metabolites of this drug in plasma as well as in rat striatum. A correlation between the actual present concentration of the parent drug and DAergic metabolites and the net action on striatal DA metabolism was found.It may be concluded that mesulergine itself lacks DAergic activity but occupies DA receptors and is very rapidly metabolized into potent DA agonists.  相似文献   
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Carbapenem-hydrolysing β-lactamases are the most powerful β-lactamases, being able to hydrolyse almost all β-lactams. They are mostly of the KPC, VIM, IMP, NDM and OXA-48 types. Their current extensive spread worldwide in Enterobacteriaceae is an important source of concern, as these carbapenemase producers are multidrug-resistant. Detection of infected patients and of carriers are the two main approaches for prevention of their spread. Phenotypic and molecular-based techniques are able to identify these carbapenemase producers, although with variable efficiencies. The detection of carriers still relies mostly on the use of screening culture media.  相似文献   
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