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31.
J. Mertens 《European archives of oto-rhino-laryngology》1991,248(7):395-399
Summary The influence of simple opening of the round window (RW) membrane and the effect of aspiration of perilymph on the electrophysiological characteristics of the cochlea was tested in guinea pigs by measurement of the compound action potentials. We found that perforations of the RW membrane failed to lead to either shortterm or long-term damage in cochlear function. There was only a slight spontaneous escape of perilymph but without measurable functional loss. Additional aspiration of perilymph led to entry of air into the basal turn and to an immediate loss of function of the cochlea. This regressed within 4 weeks in the middle- and low-frequency ranges. Measurable long-term damage persisted only in the high-frequency ranges. We attribute contradictory results of other authors to methodological errors which we avoided by a specific selection of healthy animals and the development of standardized operation, recording and measurement procedures. 相似文献
32.
33.
We have studied the effects of vinblastine sulfate (VBL) and colchicine (COL) on male rat in vivo and in vitro meiosis. A novel methodology based on isolating a segment of seminiferous tubules containing meiotically dividing spermatocytes was applied. During meiotic divisions at stage XIV of rat spermatogenesis, both chemicals induced only low frequencies of micronu-clei (MN), 0.8–3.2 MN/1,000 spermatids. Fluorescence in situ hybridization experiments in mice with the mouse centromere-specific y-sat-ellite DNA probe showed that 50.7% of VBL-induced MN and 56.6% of COL-induced MN were centromere positive, indicating that the MN induced by both chemicals contained detached chromosomes. The inhibition of cell proliferation was determined by counting the number of cells arrested at metaphase during the first meiotic (MI) or the second meiotic (MII) division. VBL was found to be a potent inducer of cell death while COL was not. The direct effects of VBL and COL on the meiotic spindles were evaluated using immunohistochemistry with anti-a-tubulin and confocal microscopy. In the control animals a significant difference was observed between the mean length of metaphase spindles of MI and MII Both were dramatically decreased 6 hr after treatment with 2.0 mg/kg of VBL and 0.8 mg/kg of COL, respectively. At 18 hr after COL injection the spindles had about the same length as in the controls. However, the VBL-induced shortening was even more evident at 18 hr for both Ml and Mll. The possible reasons for observed differences between the two chemicals and between meiosis and mitosis are discussed. © 1995 Wiley-Liss, Inc. 相似文献
34.
作者设计用碱性淋洗技术探讨了小鼠受低剂量147Pm内污染时对精子DNA链修复的刺激效应。动物预先在睾丸内注入3H-TdR,用以标记精子DNA,从标记到采集精子的时间固定为36天,正好为BALB/c小白鼠雄性生殖细胞的一个发育周期.从摄入147Pm到采集精子的时间则固定在12天,因这时小白鼠精子DNA链断裂的洗脱量最大,待精子被溶胞液溶破后,加入淋洗液,调节蠕动泵流量定时收集标本,用液闪装置测量膜上标本和膜下各收集标本的放射性活度,从而判断各标本中DNA的量。研究结果发现,当机体内污染低剂量147Pm在0.185kBq/g时,此时的膜上DNA存留率呈现升高,显著高于相应对照组,表明低剂量裂片147Pm内照射对精子DNA链修复的刺激效应。 相似文献
35.
Nasrin Moghadami Tabrizi Babak Dabirashrafi Parisa Salehi Shahram Shams Hormoz Dabirashrafi 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2006,10(1):74-75
Objectives:
To determine the cause of severe, disabling, groin pain.Methods:
We describe in this case report 2 patients with severe groin pain. Two myoma-like masses were found on the uterus near the right round ligament. Both masses were excised via laparoscopy.Results:
The pathology report of these 2 cases indicated adenomyosis. Both patients were asymptomatic after the procedure. Adenomyosis usually propagates in the myometrium, and the nodular shape of this pathology is rare. In patients with severe groin pain (menstrual or continuous), the gynecologist should think about both endometriosis of the round ligament and adenomyosis near the round ligament.Conclusion:
Severe groin pain is rare but disabling. Endometriosis of the external part of the round ligament is described as a cause. In this case report, we explain that nodular adenomyosis can also be a cause. 相似文献36.
B. Rousselin M.D. D. Vanel M.D. M. J. Terrier-Lacombe M.D. B. J. M. Istria M.D. M. Spielman M.D. J. Masselot M.D. 《Skeletal radiology》1989,18(2):115-120
Radiographs and clinical charts were reviewed in a series of 13 cases of primary neuroectodermal bone tumors, involving 9 males and 4 females, aged from 3 to 32 years (average: 15 years). The average delay between the onset and diagnosis was 5 months. Fever and other systemic symptoms were present in 6 cases; in 4 cases a fracture was the mode of presentation. Seven patients had metastases (4 involving bone) at the time of presentation. Only one patient is still alive after 5 years. In the 10 patients who died as a direct result of the tumor, death occured on average 8 months following diagnosis if metastases were present initially, and 36 months after the diagnosis otherwise. Tumors predominantly involved the leg (7 cases), the pelvis (2 cases), and the humerus (2 cases), the involvement being both diaphyseal and metaphyseal. The radiologic appearance is that of an aggressive, poorly demarcated tumor, with cortical destruction, periosteal reaction and soft tissue invasion. Comparison with Ewing sarcoma shows little radiologic or clinical difference, except for a poorer prognosis in neuroectodermal bone tumors. Both bone tumors may have a similar neuroectodermal origin, with Ewing sarcoma representing the undifferentiated variety. 相似文献
37.
Inflammatory myofibroblastic tumor is an intermediate-grade neoplasm with potential for recurrence and rare metastasis. Rearrangement of the anaplastic lymphoma kinase gene with variable fusion partners and anaplastic lymphoma kinase expression using immunohistochemistry are noted in about half of the tumors. We present a hepatic inflammatory myofibroblastic tumor from a 34-year–old man with an unusual rearrangement between the Ran binding protein 2 and anaplastic lymphoma kinase genes, as well as a peculiar round cell transformation of tumor cells and a unique nuclear membrane expression of anaplastic lymphoma kinase protein. As the fourth reported inflammatory myofibroblastic tumor with this fusion so far, we find that these genetic and morphologic features may be related to a poor clinical outcome. The diagnostic difficulty and other prognostic factors of inflammatory myofibroblastic tumor are also discussed. 相似文献
38.
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40.
Kazuo Suzuki Kaoru Yanagida R. Yanagimachi 《Journal of assisted reproduction and genetics》1998,15(3):154-157
Purpose:
This study investigated whether K
+
-rich medium is better than pure NaCl solution or Na
+
-rich cell culture medium for handling round spermatid nuclei prior to injection into oocytes (ROSNI).
Methods:
Round spermatids of the mouse were isolated and stored in isotonic NaCl, a cell culture medium (CZB), or a nucleus isolation medium (NIM) before injection into oocytes. The rates of normal fertilization, embryonic development in vitro, and birth of normal offspring after transfer of embryos to foster mothers were determined.
Results:
In vitro development of ROSNI-produced zygotes to blastocysts was the same when naked spermatid nuclei were exposed briefly to three media. However, a long (60-min) exposure of the nuclei to NA
+
-rich medium was detrimental. In K
+
-rich NIM naked spermatid nuclei best retained their ability to participate in normal embryonic development.
Conclusion:
NIM was better than Na
+
-rich medium for retaining isolated spermatids competent to participate in normal embryonic development. 相似文献