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81.
Male subfertility induced by acute scrotal heating affects embryo quality in normal female mice 总被引:5,自引:0,他引:5
Jannes P; Spiessens C; Van der Auwera I; D'Hooghe T; Verhoeven G; Vanderschueren D 《Human reproduction (Oxford, England)》1998,13(2):372-375
The aim of this experiment was to design a suitable mouse model for male
subfertility in which to study the effect of decreased sperm quality on
embryo quality in vivo and in vitro. To achieve male subfertility, testes
of adult male mice were immersed in water at either 42 degrees C (heated)
or 33 degrees C (controls) during 20 min. Twenty-eight days after
treatment, all heat stressed males showed a significant decrease in
relative testis weight [384.7 mg in controls (286.7-460.6) versus 323 mg in
stress heated groups (117.9-405.6); P < 0.001], sperm concentration
[3.75 x 10(6)/ml (2.75-7.25) versus 1.00 x 10(6)/ml (0-4.00); P < 0.001]
and progressive sperm motility [57.5% (48.0-79.0) versus 42.5% (14.0-66.0);
P < 0.001]. Moreover, after mating to heat exposed males, not only the
number of pregnant females (20/22 versus 18/30) but also the weight of
their embryos [275.4 mg (78.7-339.4) versus 261.8 mg (68.1-339.0); P <
0.001] was significantly lower at 14.5 days post coitum when compared to
controls. Neither the number of resorption sites nor the number of viable
embryos per pregnant female was significantly different between groups.
Also, the in-vitro fertilization rate of oocytes, fertilized by spermatozoa
collected from heat stressed males, was significantly lower (44.9%; P <
0.0001) when compared to controls (65.1%; P < 0.0001). In conclusion,
the results of this study suggest that male subfertility induced by acute
scrotal heating may result in impaired sperm quality, reduced embryo weight
in vivo and decreased fertilization rate in vitro.
相似文献
82.
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This report looks at outpatient treatment of nasopharyngeal inlet stenosis, a more commonly seen postoperative complication of uvulopalatopharyngoplasty (UPPP). It does not study the effectiveness of the UPPP for treatment of obstructive sleep apnea syndrome (OSAS). The authors evaluated six patients who had a UPPP for OSAS, all of whom developed stenosis in the nasopharyngeal inlet ranging from 14 mm to complete closure. Two patients had failed rotation flap repairs. The carbon dioxide laser was used to treat these patients in the office under a local anesthesia in a staged manner. We now have patients from 3 months to 12 months follow-up who have had stenosis treated successfully. We believe that the postoperative complication of nasopharyngeal inlet stenosis after UPPP can be treated in a safe and cost-effective manner in the office setting. 相似文献
84.
85.
Martin Klomp Peter M. Van den Bergh Frits J. H. Harinck 《Child & youth care forum》1997,26(5):343-355
In child and youth care in the Netherlands, systematic planning of treatment is more and more considered to be a condition
for effective and well founded treatment. Although workers are convinced of the benefits of treatment plans, treatment planning
is not yet a natural and integrated part of residential care. There are several pressure points. In this article a model of
treatment planning will be presented that contributes to an answer to these pressure points. The theoretical bases and the
practical implications of this model will be discussed. 相似文献
86.
Jaafar Mouhyi Lars Sennerby Jeanjacques Pireaux Nicolas Dourov Samir Nammour Jack Van Reck 《Clinical oral implants research》1998,9(3):185-194
The purpose of the present study was to analyse clinically failed and retrieved implants prior to and after cleaning by means of scanning electron microscopy (SEM) and X-ray induced photoelectron spectroscopy (XPS) as compared to unused controls. Six different chemical and physical techniques for cleaning of contaminated titanium implants were evaluated: 1) rinsing in absolute ethanol for 10 min, 2) cleaning in ultrasonic baths containing trichloroethylene (TRI) and absolute ethanol, 10 min in each solution, 3) abrasive cleaning for 30 s, 4) cleaning in supersaturated citric acid for 30 s, 5) cleaning with continuous CO2-laser in dry conditions at 5 W for 10 s, 6) cleaning with continuous CO2-laser in wet conditions (saline) at 5 W for 10 s. SEM of failed implants showed the presence of contaminants of varying sizes and XPS showed almost no titanium but high carbon signals. XPS of unused titanium implants showed lower levels of titanium as previously reported, probably due to contamination of carbon which increased with time in room air. Cleaning of used implants in citric acid followed by rinsing with deionized water for 5 min followed by cleaning in ultrasonic baths with TRI and absolute ethanol gave the best results with regard to macroscopical appearance and surface composition. However, as compared to the unused implants the results from an element composition point of view were still unsatisfactory. It is concluded that further development and testing of techniques for cleaning of organically contaminated titanium is needed. 相似文献
87.
L.-J. Van Bogaert 《Medical hypotheses》1997,48(6):485-488
With spinal anesthesia the level of surgical analgesia is mostly reported without reference to the neuroanatomic map of spinal nerves. The classical maps are variably and inconsistently reported in many textbooks. Because of the differences between the classical maps of Keegan and Garrett and of Foerster, and also because of the variability in their interpretation, we applied them to the same clinical data. This resulted in a theoretically clinically significant difference of two segments. It is concluded that clear reference should be made to the implemented segmental map in expressing the level of spinal blockade. 相似文献
88.
Arnold Criel Gregor Verhoef Robert Vlietinck Cristina Mecucci Johan Billiet Lucienne Michaux Peter Meeus ries Louwagie Angeline Van Orshoven Achiel Van Hoof Mark Boogaerts Herman Van den Berghe & Chris De Wolf-Peeters 《British journal of haematology》1997,97(2):383-391
We analysed a group of 390 patients, diagnosed with chronic lymphocytic leukaemia (CLL). Cases were subclassified as morphologically typical and atypical CLL according to the criteria of the FAB proposal. Typical CLL cases were mostly diagnosed at a low-risk stage (Binet A/Rai 0), required no immediate treatment and expected a long survival; atypical CLL cases mostly presented at a more advanced risk stage (Binet B/Rai I–II), usually required immediate treatment and their survival was shorter. Moreover, clinical staging was of prognostic significance in typical but not in atypical cases. In typical CLL, del(11q) was the most common chromosomal abnormality (21%) whereas in atypical CLL trisomy 12 was found in about 65% of the cases documented with an abnormal karyotype. Although chromosomal abnormalities were associated with a poor survival in typical CLL, they are of no prognostic significance in atypical CLL. Based on these data, we conclude that subtyping CLL by morphology enables the identification of two groups of cases, each characterized by a specific clinical presentation, different cytogenetic abnormalities and prognostic parameters. We speculate that these two groups may represent two related, but different, diseases with different prognostic parameters and a different survival. 相似文献
89.
90.