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21.
Silber SJ; Nagy Z; Devroey P; Tournaye H; Van Steirteghem AC 《Human reproduction (Oxford, England)》1997,12(11):2422-2428
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
22.
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
23.
K Schunk C D Gerharz F X Schmid H Schild 《R?ntgen-Bl?tter; Zeitschrift für R?ntgen-Technik und medizinisch-wissenschaftliche Photographie》1987,40(11):373-375
After presenting an own case of a cavernous hemangioma of the mediastinum, the clinical pattern, differential diagnosis, diagnostic procedure (computed tomography), and therapy of this rare tumor form are described. 相似文献
24.
Spatial Learning Deficits in Mice with a Targeted Glucocorticoid Receptor Gene Disruption 总被引:5,自引:0,他引:5
Melly S. Oitzl E. Ron de Kloet Marian Joëls Wolfgang Schmid Timothy J. Cole 《The European journal of neuroscience》1997,9(11):2284-2296
Previous studies in rats using the Morris water maze suggested that the processing of spatial information is modulated by corticosteroid hormones through mineralocorticoid and glucocorticoid receptors in the hippocampus. Mineralocorticoid receptors appear to be involved in the modulation of explorative behaviour, while additional activation of glucocorticoid receptors facilitates the storage of information. In the present study we used the water maze task to examine spatial learning and memory in mice homozygous and heterozygous for a targeted disruption of the glucocorticoid receptor gene. Compared with wild-type controls, homozygous and heterozygous mice were impaired in the processing of spatial but not visual information. Homozygous mutants performed variably during training, without specific platform-directed search strategies. The spatial learning disability was partly compensated for by increased motor activity. The deficits were indicative of a dysfunction of glucocorticoid receptors as well as of mineralocorticoid receptors. Although the heterozygous mice performed similarly to wild-type mice with respect to latency to find the platform, their strategy was more similar to that of the homozygous mice. Glucocorticoid receptor-related long-term spatial memory was impaired. The increased behavioural reactivity of the heterozygous mice in the open field points to a more prominent mineralocorticoid receptor-mediated function. The findings indicate that (i) the glucocorticoid receptor is of critical importance for the control of spatial behavioural functions, and (ii) mineralocorticoid receptor-mediated effects on this behaviour require interaction with functional glucocorticoid receptors. Until the development of site-specific, inducible glucocorticoid receptor mutants, glucocorticoid receptor-knockout mice present the only animal model for the study of corticosteroid-mediated effects in the complete absence of a functional receptor. 相似文献
25.
26.
Ambuhl P; Wuthrich R; Korte W; Schmid L; Krapf R 《Nephrology, dialysis, transplantation》1997,12(11):2355-2364
Background: Thrombotic complications are common in
patients with endstage renal disease and contribute substantially to the
morbidity and mortality in this population. The aim of the present study
was to: I) determine the prevalence and the extent of hypercoagulability in
patients undergoing dialysis treatment by measuring parameters that
directly reflect thrombin concentrations, ii) assess changes in coagulation
status during haemodialysis (HD); iii) quantify the relative impact of
heparin, dialysis and their combined effects on coagulation status and iv)
detect factors that modify coagulation haemostasis in dialysis patients.
Method: A total of 39 patients (HD: n=29, CAPD: n=10)
was analysed for procoagulatory and fibrinolytic activity determined by
measurements of partial thromboplastin time, prothrombin fragments F1+2,
thrombin-antithrombin complexes and D-dimer concentrations. HD patients
were investigated prior to and during dialysis. A subgroup of patients was
infused heparin alone without dialysis or was dialysed without heparin
administration. Furthermore, subgroup and correlation analyses were
performed for the type of dialysis (HD vs CAPD), dialyzer and shunt, Kt/V,
underlying disease and treatment with recombinant erythropoietin (rhEPO).
Results: Baseline levels of all
parameters-procoagulatory and fibrinolytic- were substantially elevated in
all patients, but to a higher degree among those on CAPD. Moreover,
haemodialysis treatment increased procoagulatory markers even further,
suggesting stimulated coagulation and/or insufficient anticoagulation
during dialysis. However, after 3 h of dialysis thrombin concentrations,
determined by quantification of prothrombin fragments, were inversely
correlated with Kt/V. Selective heparin infusion diminished procoagulatory
activity only slightly and incompletely, whereas HD without heparin
resulted in excess thrombin accumulation. Finally, subgroup analyses
revealed more pronounced thrombin formation among patients treated with
polysulfon dialyzers, whereas erythropoietin dosage was positively related
with lower procoagulatory activity. Conclusion: A
majority of patients on dialysis are in a hypercoagulable state, which is
further aggravated by the haemodialysis procedure itself and may not be
sufficiently controlled with current anticoagulation regimens. Intensified
heparin treatment and the use of rhEPO are likely to improve coagulation
haemostasis, whereas the type of dialyzer should be considered as a
relevant procoagulatory factor. 相似文献
27.
28.
29.
In this morphometric study, terminal villi of 22 placentas of maternal diabetes mellitus were compared with the results in terminal villi of 22 normal placentas. The results demonstrate that there is a distinct retardation in maturation, statistically significant with bigger cross sectional surfaces of the terminal villi, particularly, when classified in 3000 mu2-steps, the number of the villous vessels and number of epithelial plates. Only slightly decreased in diabetic placentas is the villous vessels cross sectional surface as well as the degree of vascularization. The correlation between the degree of histometric changes and the severity and duration of the disease was separately investigated (classification was done according to White). It could be shown, that the degree of morphologic changes in the terminal villi does not run strictly parallel to the severity and duration of diabetes. The retardation in maturation of the terminal villi increases from White group A to C. In White group D, which is the most severe stage of diabetes mellitus which we investigated, the values of measured parameters are close to the normal placentas. This observation is interpreted as a compensatory reaction of the fetal organ placenta to the reduction in utero placental blood flow in diabetes caused by the diabetic angiopathy. 相似文献
30.
Hoschek Stefan Hoschek-Risslegger Ursula Fiegl Michael Zabernigg August Pall Georg Auberger Thomas Gunsilius Eberhard Schmid Thomas Jamnig Herbert Hilbe Wolfgang 《Wiener Medizinische Wochenschrift》2007,157(21):562-568
Wiener Medizinische Wochenschrift - Aggressives Tumorwachstum, frühe Metastasierung und hohe Assoziation mit intensivem Nikotinkonsum sind die Charakteristika des kleinzelligen... 相似文献