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Beeri Rachel; Gnatt Averell; Lapidot-Lifson Yaron; Ginzberg Dalia; Shani Moshe; Soreq Hermona; Zakut Haim 《Human reproduction (Oxford, England)》1994,9(2):284-292
Gene amplification occurs frequently in tumour tissues yet is,in general, non-inheritable. To study the molecular mechanismsconferring this restraint, we created transgenic mice carryinga human butyrylcholinesterase (BCHE) coding sequence, previouslyfound to be amplified in a father and son. Blot hybridizationof tail DNA samples revealed somatic transgene amplificationswith variable restriction patterns and intensities, suggestingthe occurrence of independent amplification events, in 31% (11/35)of mice from the FII generation but in only 3.5% (2/58) of theFII and FIV generations. In contrast, >10-fold amplificationsof the BCHE transgene and the endogenous acetylcholinesteraseand c-raf genes appeared in both testis and epididymis DNA from>80% of FIII mice. Drastic, selective reductions in testisBCHEmRNA but not in actin mRNA were detected by the PCR amplificationof testis cDNA from the transgenic mice, and apparently resultedin the limited transmission of amplified genes. The testicularamplification of the BCHE transgene may potentially representa general phenomenon with clinical implications in human infertility. 相似文献
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Axial computed tomographic (CT) scan of the lumbosacral region was performed in 220 patients. The patient population was divided into three groups. The control group included 40 elderly patients without calcification of the ligamenta flava. The second group included 150 patients with posterior protrusion of the intervertebral discs. The third group included 30 patients with spinal stenosis. More than 80% of the patients of the second and the third group had calcification of the ligamenta flava. The diagnostic and practical importance of these findings is discussed. 相似文献
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Yuval Dror 《Child & youth care forum》1995,24(3):195-208
Internal totality and community orientation are two pivotal components, difficult to measure, in the literature on residential education (including both residential schools for the elite and group or congregate care and education programs for marginal youth). We propose a two-dimensional model based on historical research and contemporary study to define and differentiate these concepts. Internal totality can be measured through the links and balance between the formal curriculum, extra curriculum, and out of school (nonformal) activities; community orientation through links between the residential and ideological community, the local community, and the wider community. Implications for practice, policy, and further research are suggested.Oranim is the School of Education of the Kibbutz Movement, affiliated with the University of Haifa. 相似文献
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Gonadotropin (taGTH) secretion from perifused fragments of tilapia pituitaries was stimulated in a dose-dependent manner by an analog of gonadotropin-releasing hormone ([D-Ala6] des Gly10 ethylamide LHRH; GnRHa) in a dose range of 1.28 to 128 pM. The baseline secretion rate and taGTH secretion in response to GnRHa were both reduced when the perifusion medium lacked Ca2+. Calcium ionophore (A23187; 0.1 mM) mimicked the effect of GnRHa but only in the presence of Ca2+. The addition of cobalt chloride to the medium at 0.6 mM initially caused an increase in taGTH secretion which was followed by its decrease. At a CoCl2 concentration of 1.3 mM, the baseline secretion rate remained low and the effect of GnRHa on taGTH secretion was attenuated. Withdrawal of CoCl2 from the medium was followed by an elevated basal secretion rate. Five-minute pulses of the protein kinase C activator, 1 oleyl-2-acetyl-rac-glycerol (OAG; 0.25 to 10.4 mM) stimulated taGTH secretion in the presence of Ca2+. With the reservation that the experiments were performed on fragments containing more than one pituitary cell type, the results indicate that the stimulation of GTH secretion in this fish is dependent, as in mammals, on extracellular Ca2+ and probably involves the activation of protein kinase C. However, the fact that taGTH may be stimulated to some extent in the absence of extracellular calcium or in the presence of 1.3 mM Co2+ may point to the possibility that Ca2+ is mobilized from intracellular stores as a result of GnRH stimulation or to the involvement of an additional mechanism of GnRH action in fish independent of calcium. 相似文献
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Navon-Venezia S Leavitt A Ben-Ami R Aharoni Y Schwaber MJ Schwartz D Carmeli Y 《Journal of clinical microbiology》2005,43(1):439-441
We evaluated a protocol for the accelerated detection of extended-spectrum beta-lactamases (ESBLs) in gram-negative bloodstream pathogens. Two hundred eighty-three blood culture bottles were subjected to direct ESBL testing by inoculating samples directly from blood culture bottles onto agar plates containing cefotaxime and ceftazidime disks, with and without clavulanate. Standard ESBL testing in accordance with the NCCLS guidelines after subculturing on agar plates was performed in parallel. Results of the direct ESBL testing were reported 2.3 days sooner and were comparable to those of the standard NCCLS method with sensitivity, specificity, and positive and negative predictive values of 100, 98, 94, and 100%, respectively. 相似文献
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Einat Rabinovitch Dror Harats Pnina Yaron Tamar Luvish Merav Lidar Ron Kedem Aviv Shaish Issahar Ben-Dov Avi Livneh 《Annals of allergy, asthma & immunology》2007,99(6):517-521
BACKGROUND: Asthma is an inflammatory airway disease caused by interaction between susceptibility genes and diverse environmental factors. In Israel, asthma seems to be familial and more severe in patients of Iraqi Jewish descent. On the other hand, asthma is less frequent in individuals with familial Mediterranean fever, an autoinflammatory disease prevalent in the Iraqi Jewish community and linked to mutations in the familial Mediterranean fever gene, designated MEFV. OBJECTIVES: To explore a possible role for mutated MEFV in the reduced susceptibility to asthma and to determine its expression in Israeli subjects of Iraqi origins. METHODS: Using a case-control approach, we studied the presence of the 3 most common MEFV mutations (M694V, V726A, and E148Q) in DNA samples from 75 patients with asthma and 45 asymptomatic first-degree relatives, all of Iraqi Jewish origin. The severity of asthma was evaluated using a published severity score. RESULTS: Eleven patients with asthma and 14 of their relatives carried 1 or 2 mutations in the MEFV gene, a carrier rate significantly lower in patients with asthma than in their first-degree relatives and in ethnically matched healthy individuals (P < .03 and P < .003, respectively). Carriers of MEFV mutations had less severe disease, compared with noncarriers (P < .002). CONCLUSION: These findings suggest that MEFV mutations may have a protective effect in the pathogenesis of asthma. 相似文献