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971.
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
972.
C. Z. BACHRATI Z. SOMODI E. ENDREFFY T. KALMÁR I. RASKÓ 《Annals of human genetics》1998,62(6):511-520
Duchenne and Becker muscular dystrophies are among the most severe and frequent inherited disorders. Being still incurable, medical treatment is concentrated on the carrier diagnosis of the members of the affected families. Here we report the results of the studies of 151 members of 41 Hungarian families, obtained with multiplex PCR amplification of 18 exons as well as the muscle specific promoter region, and haplotype analysis of two polymorphic (CA)n repeat microsatellite loci in introns 45 and 49 of the dystrophin gene. The analysis of 15 deletion-type families revealed a frequency of new mutations not differing significantly from that in the other regions of Europe. We also compared the allele distributions of the two microsatellites in randomly selected normal individuals and affected family members. The allele distribution of STRP45 shows interesting differences between the two populations. 相似文献
973.
C. T. Laurencin R. S. Cummings T. R. Jones L. Martin 《Journal of the National Medical Association》1998,90(12):779-781
Bony fusions involving the carpus have a much higher prevalence in blacks relative to whites. This article describes a case of lunotriquetral coalition fracture-dislocation in an African American. This lesion is best treated through open reduction and pin fixation. 相似文献
974.
E.Paul Kirk MB BS J. Santa MD T. Heckler MBA M. Collins MD 《American journal of obstetrics and gynecology》1998,178(6):1222-1228
OBJECTIVE: Our purpose was to assess whether legislative action influenced the role of obstetrician-gynecologists as primary care physicians. STUDY DESIGN: An observational study was performed on the basis of a questionnaire sent to 410 obstetrician-gynecologists and 27 medical directors of managed-care organizations. RESULTS: Of 67% of obstetrician-gynecologists and 96% of medical directors who responded, there was agreement as to the content of primary care, but a minority (38%) of obstetrician-gynecologists identified themselves as primary care providers. A minority of medical directors (35%) felt that obstetrician-gynecologists should serve in that role. Both obstetrician-gynecologists and medical directors felt that legislation had little impact. CONCLUSION: The reticence of obstetrician-gynecologists to assume a major role in primary care appears to be the result of an uneasiness with accepting a more comprehensive role in patient management and gatekeeping. They appear comfortable with the more traditional roles but feel that training and experience has not prepared them well for the management of more complex medical problems. (Am J Obstet Gynecol 1998;178:1222-8.) 相似文献
975.
H. Iwata T. Otoshi N. Takada T. Murai S. Tamano T. Watanabe Y. Katsura S. Fukushima 《Urological research》1995,23(1):27-32
A series of 8 rat and 16 mouse invasive bladder carcinomas were investigated for the presence of silverstained nucleolar organizer regions (AgNORs) to clarify whether this parameter is applicable to the estimation of their invasive character. With regard to number of AgNORs per cell, neither rat nor mouse carcinomas showed any difference between invasive and noninvasive sites within the same tumor. However, the frequency of cancer cells bearing bizarre dots, irregular in size and shape, was significantly higher at sites of actual invasion. Quantitative data generated using an image analyzer revealed significantly lower values for NOR roundness and significantly larger NOR size in invasive sites than in noninvasive sites in all groups. Double staining for the proliferation marker proliferating cell nuclear antigen (PCNA) and AgNORs was performed on eight rat carcinomas and a close correlation between the two was confirmed. Thus the number of AgNORs in PCNA-positive cells was significantly greater than in PCNA-negative cells. Furthermore, a particularly strong correlation was observed for incidences of PCNA-positive cells and bizarre dots (P<0.01). The quantitative data also demonstrated significant differences in size and shape of dots. It is concluded that AgNORs have diagnostic value for the invasive character of bladder carcinomas. 相似文献
976.
Summary Physeal distraction was applied with an external fixator to the triradiate cartilage of dogs with the aim of increasing the capacity of the acetabulum. The force was continued for from 2 to 6 weeks and the consequent changes were evaluated with regard to function and structure by radiography and microscopy. The distraction, without producing epiphysiolysis and destruction of the cartilage, resulted in expansion of the pelvic bones. The depth and volume of the acetabulum were increased, but the acetabular angle was decreased. Distraction also caused proliferation of the lacunar cells and the number of mammillary processes in the cartilage columns increased. Distraction can therefore be applied to the triradiate cartilage to enlarge the capacity of the acetabulum without producing epiphysiolysis.
Résumé Dans cette étude une distraction a été appliquée sur le cartilage en Y. Douze chiens bâtards, âgés de 2.5 à 4 mois, ont été utilisés pour cette expérimentation. Une force de distraction de 80 Newton a été appliquée d'emblée sur le cartilage en Y. L'application de cette force a été poursuivie sur les animaux pendant 2, 4 ou 6 semaines. A la fin de cette période, les changements de la cavité cotyloïde et du cartilage en Y ont été évalués sur le plan fonctionnel, morphologique, radiologique et histopathologique Aucune altération fonctionnelle n'a été mise en évidence dans les groupes opérés par rapport au groupe de contrôle. On a observé que la distraction a déterminé une expansion massive de l'ilion, du pubis et de l'ischion. Sur les hanches de contrôle la profondeur de la cavité cotyloïde a été évaluée à 13.5 mm, le volume à 1.96 cc et l'angle de la cavité cotyloïde à 29.9°. Après distraction ces valeurs ont été respectivement de 14.4 mm, de 2.10 cc et de 25.7°. La distraction entraîne donc un accroissement de profondeur et de volume de la cavité cotyloïde, mais inversement une diminution de l'angle de cette cavité. Ces résultats montrent que la distraction détermine une prolifération des cellules lacunaires et un accroissement des processus mammaires dans les colonnes du cartilage en Y. Ils montrent également qu'elle peut augmenter la taille de l'acetabulum.相似文献
977.
The goal of the present study is to develop a technique for laparoscopic aortobifemoral bypass.Piglets weighing between 60 and 78 kg were anesthetized with halothane. The lateral retroperitoneal approach was preferred to the more familiar anterior transperitoneal approach and was successfully completed in 19 piglets. The piglets were placed in the right lateral decubitus position. The first port (2 cm) was inserted halfway between the tip of the 12th rib and the iliac crest. Four other trocars were placed in the retroperitoneum after balloon inflation had allowed creation of a space which permitted visualization of the aorta from the left renal artery down to the aorto-iliac junction. After evacuation of the retropneumoperitoneum, the cavity was maintained using an abdominal lift device and a retractor.Using this approach, we performed four aortobifemoral bypasses (end-to-end aortic anastomosis) after conventional intravenous heparinization (100 IU/kg) in less than 4 h. Blood loss did not exceed 250 ml and the hematocrit remained stable. Postmortem evaluation of the grafts revealed they were positioned as in a conventional bypass, their limbs having followed in the created retroperitoneal tunnels along the path of the native arteries. No mortality occurred before sacrifice of the animals. We believe that this first performed series of totally retroperitoneal laparoscopic aortobifemoral bypasses in the porcine model is useful in preparation for human application due to the anatomical similarities in the periaortic region. 相似文献
978.
979.
A novel retractor has been designed to achieve atraumatic retraction of the liver and displacement of hollow viscera during endoscopic surgery. The functional section of the instrument, when locked, forms a silicon-covered uniplanar hook which can be deployed for horizontal lift of solid organs such as the liver or be used to engage bowel for displacement from the operative field. Following laboratory testing, the instrument has been evaluated clinically and its ease of deployment and atraumatic nature have been confirmed. It has been found to be particularly effective for elevation of the thick fatty left lobe of the liver during antireflux surgery. 相似文献
980.
A P Jones A Sofat C H Davis S Denton N T Gurusinghe 《British journal of neurosurgery》1990,4(3):193-197
The high cost of commercial CT-compatible stereotactic frames has restricted the availability of CT-guided stereotaxy for many neurosurgical centres. However, many of these centres do possess the standard stereotactic frames for projection radiography, of which the old type Leksell frame is probably the most common. We have devised a simple and low-cost modification to an old Leksell frame to allow CT-guided stereotaxy. The nature of the modifications allow complete freedom of positioning of the frame relative to the CT scanner and coordinate transformations can be performed simply and effectively. The modified frame has been used successfully for some 18 months and the modification has now been performed at two centres in the North West Regional Health Authority. We hope this modification will allow many other centres to embark on CT-guided stereotaxy. 相似文献