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The aim of the study was to determine whether a prior diagnostic testicle biopsy can predict success or failure of testicular sperm extraction (TESE) with intracytoplasmic sperm injection (ICSI) in patients with non-obstructive azoospermia caused by testicular failure, and what is the minimum threshold of sperm production in the testis which must be surpassed for spermatozoa to reach the ejaculate. Forty- five patients with non-obstructive azoospermia caused by testicular failure underwent diagnostic testicle biopsy prior to a planned future TESE-ICSI procedure. The diagnostic testicle biopsy was analysed quantitatively, and correlated with the quantitative findings of spermatogenesis in patients with normal spermatogenesis, as well as with the results of subsequent attempts at TESE-ICSI. Men with non- obstructive azoospermia caused by germinal failure had a mean of 0-6 mature spermatids/seminiferous tubule seen on a diagnostic testicle biopsy, compared to 17-35 mature spermatids/tubule in men with normal spermatogenesis and obstructive azoospermia. These findings were the same for all types of testicular failure whether Sertoli cell only, maturation arrest, cryptorchidism, or post-chemotherapy azoospermia. Twenty-two of 26 men with mature spermatids found in the prior testis biopsy had successful retrieval of spermatozoa for ICSI, 12 of their partners became pregnant, and are either ongoing or delivered. The study suggests that 4-6 mature spermatids/tubule must be present in the testis biopsy for any spermatozoa to reach the ejaculate. More than half of azoospermic patients with germinal failure have minute foci of spermatogenesis which are insufficient to produce spermatozoa in the ejaculate. Prior diagnostic testicle biopsy analysed quantitatively (for the presence of mature spermatids) can predict subsequent success or failure with TESE-ICSI. Incomplete testicular failure may involve a sparse multi-focal distribution of spermatogenesis throughout the entire testicle, rather than a regional distribution. Therefore, it is possible that massive testicular sampling from many different regions of the testes may not be necessary for successful TESE-ICSI.   相似文献   
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β-Lactoglobulin was isolated from infant formulae that were ultra high temperature (UHT) -treated, sterilized or spray-dried. The effect of the isolated β-lactoglobulin on SfaII-fimbriae-mediated adhesion of Escherichia coli to human ileostomy glycoproteins was studied in vitro. β-Lactoglobulin isolated from sterilized formulae was found to perform significantly less well than preparations from spray-dried formulae (p = 0:05). Great heterogeneity was observed in the adhesion inhibitory capacity of β-lactoglobulin isolated from UHT-treated formulae. Therefore, no significant difference was observed between UHT-treated and sterilized formulae or spray-dried formulae (p < 0:10). It can be hypothesized that β-lactoglobulin from spray-dried and some UHT-treated infant formulae may affect the colonization of mucous membranes by E. coli strains causing neonatal septicaemia and meningitis.  相似文献   
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Summary The coenzyme nicotinamide adenine dinucleotide (NADH) has been used in an open label trial as novel medication in 34 patients with Parkinson's disease, using an intravenous administration technique. In all patients a beneficial clinical effect was observed. 21 patients (61.7%) showed a very good (better than 30%) improvement of disability, 13 patients (38.3%) a moderate (up to 30%) improvement. Concomitant with the improvement of the disability the urine level of homovanillic acid (HVA) increased significantly in all patients (in some patients by more than a 100%). The daily on phases of the patients could be increased from 2 up to 9 hours in the individual patients by NADH administration.  相似文献   
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Recently we have described the molecular cloning of the genetic determinant coding for the S-fimbrial adhesin (Sfa), a sialic acid-recognizing pilus frequently found among extraintestinal Escherichia coli isolates. Fimbriae from the resulting Sfa+ E. coli K-12 clone were isolated, and an Sfa-specific antiserum was prepared. Western blots indicate that S fimbriae isolated from different uropathogenic and meningitis-associated E. coli strains, including O83:K1 isolates, were serologically related. The Sfa-specific antibodies did not cross-react with P fimbriae, but did cross-react with F1C fimbriae. Furthermore the sfa+ recombinant DNAs and some cloned sfa-flanking regions were used as probes in Southern experiments. Chromosomal DNAs isolated from O18:K1 and O83:K1 meningitis strains with and without S fimbriae and from uropathogenic O6:K+ strains were hybridized against these sfa-specific probes. Only one copy of the sfa determinant was identified on the chromosome of these strains. No sfa-specific sequences were observed on the chromosome of E. coli K-12 strains and an O7:K1 isolate. With the exception of small alterations in the sfa-coding region the genetic determinants for S fimbriae were identical in uropathogenic O6:K+ and meningitis O18:K1 and O83:K1 strains. The sfa determinant was also detected on the chromosome of K1 isolates with an Sfa-negative phenotype, and specific cross-hybridization signals were visible after blotting against F1C-specific DNA. In addition homology among the different strains was observed in the sfa-flanking regions.  相似文献   
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Preimplantation genetic diagnosis principles and ethics   总被引:4,自引:0,他引:4  
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