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Polycrystalline PbTe:In films on a polyimide substrate were obtained and investigated. Their structural and transport properties in a wide range of temperatures (10–300 K) were studied. The unique feature of In impurity in PbTe is the stabilization of the Fermi level (pinning effect) that allowed for the preparation polycrystalline films with the same carrier concentration. We found that heat treatment in an argon atmosphere does not change the average grain size and carrier concentration for as-grown films but greatly increases the Hall mobility and the electron mean free path. By comparing the mobility in the bulk and in the film after heat treatment, we extracted the value of the mobility that arises due to scattering at the grain boundary barriers. The ultimate goal of the present study is the development of these films in designing portable uncooled photodetectors for the mid-IR range.  相似文献   
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Genetic and epigenetic alterations have been identified as to contribute directly or indirectly to the generation of transitional cell carcinoma of the urinary bladder (TCC-UB). In a comparative fashion much less is known about copy number alterations in TCC-UB, but it appears that amplification of chromosome 6p22 is one of the most frequent changes. Using fluorescence in situ hybridization (FISH) analyses, we evaluated chromosomal 6p22 amplification in a large cohort of bladder cancer patients with complete surgical staging and outcome data. We have also used shRNA knockdown candidate oncogenes in the cell based study. We found that amplification of chromosome 6p22.3 is significantly associated with the muscle-invasive transitional cell carcinoma of the urinary bladder (TCC-UB) (22%) in contrast to superficial TCC-UB (9%) (p=7.2-04). The rate of 6p22.3 amplification in pN>1 patients (32%) is more than twice that in pN0 (16%) patients (p=0.05). Interestingly, we found that 6p22.3 amplification is as twice as high (p=0.0201) in African American (AA) than European American (EA) TCC-UB patients. Moreover, we showed that the expression of some candidate genes (E2F3, CDKAL1 and Sox4) in the 6p22.3 region is highly correlated with the chromosomal amplification. In particular, knockdown of E2F3 inhibits cell proliferation in a 6p22.3-dependent manner, whereas knockdown of CDKAL1 and Sox4 has no effect on cell proliferation. Using gene expression profiling, we further identified some common as well as distinctive subset targets of the E2F3 family members. In summary, our data indicate that E2F3 is a key regulator of cell proliferation in a subset of bladder cancer and the 6p22.3 amplicon is a biomarker of aggressive phenotype in this tumor type.  相似文献   
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Data on admissions of schizophrenia- and schizoaffective disorder patients to Tel-Aviv's seven public psychiatric hospitals during 11 consecutive years were obtained along with relevant meteorological information. Mean monthly admission rates were significantly higher during the summer (for schizophrenia patients) and fall (for schizoaffective patients). Schizophrenia patients' mean monthly admission rates correlated with mean maximal monthly environmental temperature (R = 0.35, N = 132 months, P <0.001). The present study may indicate that persistent high environmental temperature may be a contributing factor for psychotic exacerbation in schizophrenia patients and their consequent admission to mental hospitals.  相似文献   
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OBJECTIVE: Videolaparoscopic surgery conducted on small animals has proved to be of great importance for the improvement of surgical skills. This is a report utilizing an experimental model for laparoscopic orchiectomy and nephrectomy in training courses for urologists. MATERIAL AND METHODS: Of 350 American Wistar rats enrolled, 319 animals underwent laparoscopic orchiectomy and nephrectomy under intraperitoneal general anesthesia. Graspers, dissectors, and a 0-degree telescope were introduced into the peritoneal cavity by two trocars of 5 mm and one of 10 mm, respectively. RESULTS: Of 350 rats enrolled, 15 (4.2%) died due to anesthetic complications and 16 (4.5%) due to cannibalism and stress during transport. A total of 319 rats were operated on, 178 underwent bilateral orchiectomy, two per model (356 operations), and in 141 animals one nephrectomy per model (141 operations) was performed. A total of 497 operations were performed involving 140 urologists. The animals were easy to handle providing adequate practice without the occurrence of any major intraperitoneal lesion and hemorrhage. CONCLUSION: Nephrectomy and orchiectomy are feasible in rats, and this model can be utilized for training videolaparoscopic surgeries.  相似文献   
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