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991.
Toshiki Matsubara Takahiko Funabiki Osamu Jinno Yoichi Sakurai Shigeru Hasegawa Hiroki Imazu Masahiro Ochiai 《Journal of Hepato-Biliary-Pancreatic Surgery》1999,6(3):286-293
To investigate the molecular mechanisms of the high incidence of carcinogenesis in the biliary epithelium of patients with
pancreaticobiliary maljunction, we examined p53 gene mutations, loss of heterozygosity of p53, and overexpression of p53 gene product in the cancerous and noncancerous biliary epithelium of 27 patients with pancreaticobiliary maljunction. Mutations
of the p53 gene were examined by polymerase chain reaction-single strand conformation polymorphism and a direct sequencing method. Loss
of heterozygosity of the p53 gene was determined using a double-targeted fluorescence in situ hybridization method. Expression of p53 gene product was
examined using immunohistochemical staining. Mutations of the p53 gene were found in 4 of 5 biliary carcinomas (80%) and in 10 of 26 noncancerous biliary lesions (38.5%). Point mutations
of the p53 gene were detected at codons 207, 212, and 217 on exons 5 through 8. The incidence of p53 gene mutations on exons 5, 6, 7, and 8 was 12.9%, 36.4%, 0.0%, and 13.8%, respectively. Loss of heterozygosity of p53 was
shown in 72% of the cells obtained from the cancerous lesion, and in an average of 14% obtained from the noncancerous lesions.
Overexpression of p53 protein was found in 57.1% of carcinoma, and in 31.3% of the noncancerous lesions. These results suggest
that p53 gene mutations are involved in the carcinogenesis of biliary epithelium in patients with pancreaticobiliary maljunction.
Received for publication on Feb. 5, 1999; accepted on March 29, 1999 相似文献
992.
Toyohi Isse Yoichi Ueta Ryota Serino Jun Noguchi Yukiyo Yamamoto Masayoshi Nomura Izumi Shibuya Stafford L. Lightman Hiroshi Yamashita 《Brain research》1999,846(2):5415-235
Fasting induced a reduction in neuronal nitric oxide synthase (nNOS) mRNA in the paraventricular nucleus (PVN) and supraoptic nucleus (SON) of rats. The effect of intracerebroventricular (i.c.v.) administration of leptin on the nNOS mRNA level in the PVN and SON of fasting rats was studied by in situ hybridization histochemistry. Leptin (10 microg/kg b.wt) or vehicle was administered i.c.v. at 1700 h on two successive days fasting for 2 days. Fasting for 2 days with i.c.v. administration of vehicle induced a significant reduction of nNOS mRNA in the PVN and SON. Central administration of leptin prevented the fasting-induced reduction of nNOS mRNA in the PVN and SON. Administration of leptin also prevented the fasting-induced reductions of thyrotropin-releasing hormone (TRH) and corticotropin-releasing hormone (CRH) mRNAs in the parvocellular division of the PVN. These results suggest that leptin is associated with fasting-induced reduction of nNOS mRNA in the PVN and SON as well as TRH and CRH mRNAs in the PVN. 相似文献
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995.
Atsushi Hiraoka Miho Onishi Satsuki Koyama Masaya Kato Kaori Marui Taisei Murakami Kei Onishi Tomoko Adachi Junko Matsuoka Hidetaro Ueki Takeaki Yoshino Miho Tsuruta Toshihiko Aibiki Tomonari Okudaira Taira Kuroda Ryuichiro Iwasaki Yoshifumi Suga Hideki Miyata Tomoyuki Ninomiya Masashi Hirooka Masanori Abe Bunzo Matsuura Kojiro Michitaka Yoichi Hiasa 《Internal medicine (Tokyo, Japan)》2021,60(20):3195
Objective This study evaluated cases of pruritus, which is known to be associated with sleep disorder, in chronic liver disease (CLD) patients. Methods Questionnaires were given to 339 enrolled CLD outpatients in winter (November 2019 to March 2020) and again in summer (April to October 2020) (median interval: 104 days). Relative changes in symptoms shown by a visual analogue scale (VAS) and Kawashima''s pruritus score between winter and summer were evaluated in Study 1 (n=199), while Study 2 examined the clinical features of patients with sleep disorder based on the results of the second questionnaire (n=235, median age 70 years old; 141 men, liver cirrhosis 37%). Results Study 1. There was a significant relationship in VAS between daytime and nighttime for each season, as well as between winter and summer for each time period (p<0.001). A comparison of Kawashima''s pruritus scores for the daytime and nighttime showed no significant seasonal differences (p=0.436 and 0.828, respectively). When Kawashima''s score increased, so did the average VAS for both daytime (0:1:2:3:4=0.4±0.2:1.4±0.9:3.0±1.8:5.9±2.1:6.2±2.3) and nighttime (0:1:2:3:4=0.3±0.1:1.4±1.5:3.5±2.3:6.7±2.6:6.9±1.8) (p<0.001 for both). Study 2. Twenty subjects (8.5%) complained of sleep disorder. An elevated FIB-4 index (≥3.07) showed a good predictive value for sleep disorder (p<0.01). The cut-off for the daytime and nighttime VAS values for existing sleep disorder were 1.6 [area under the curve (AUC) 0.901] and 3.4 (AUC 0.931). The respective sensitivity, specificity, and positive and negative predictive values for sleep disorder based on Kawashima''s score (≥2) were 0.85, 0.28, 0.10, and 0.95 for the daytime and 1.00, 0.29, 0.12, and 1.00 for the nighttime. Conclusion Intervention against pruritus is recommended in CLD patients with a high Kawashima''s score (≥2) in any season, especially with an elevated FIB-4 index. 相似文献
996.
Takashi Ishiguro Yasuhito Kobayashi Yosuke Shimizu Yukari Uemura Taisuke Isono Kenji Takano Takashi Nishida Yoichi Kobayashi Chiaki Hosoda Yotaro Takaku Yoshihiko Shimizu Noboru Takayanagi 《Internal medicine (Tokyo, Japan)》2021,60(23):3709
Objective Viral pneumonia is not rare in community-acquired pneumonia (CAP). Mixed or secondary pneumonia (coinfection) can be seen in viral pneumonia; however, its frequency in coronavirus disease 2019 (COVID-19) has only been investigated in a few studies of short duration, and its significance has not been fully elucidated. We investigated the frequency and significance of co-infection in patients with COVID-19 over a 1-year study period. Methods Coinfection was investigated via multiplex polymerase chain reaction (PCR), culture of respiratory samples, rapid diagnostic tests, and paired sera. We used logistic regression analysis to analyze the effect of coinfection on severity at admission and Cox proportional-hazards model analysis to analyze the effect of coinfection on need for high-flow nasal cannula, invasive mandatory ventilation use, and death, respectively. Patients We retrospectively investigated 298 patients who suffered CAP due to severe acute respiratory syndrome coronavirus-2 infection diagnosed by PCR and were admitted to our institution from February 2020 to January 2021. Results Primary viral pneumonia, and mixed viral and bacterial pneumonia, accounted for 90.3% and 9.7%, respectively, of COVID-19-associated CAP, with viral coinfection found in 30.5% of patients with primary viral pneumonia. Influenza virus was the most common (9.4%). Multivariable analysis showed coinfection not to be an independent factor of severity on admission, need for high-flow nasal cannula or invasive mandatory ventilation, and mortality. Conclusion Viral coinfection was common in COVID-19-associated CAP. Severity on admission, need for high-flow oxygen therapy or invasive mandatory ventilation, and mortality were not affected by coinfection. 相似文献
997.
Hironobu Ito Masami Yoshimoto James S. Albert Yoichi Yamane Naoyuki Yamamoto Nobuhiko Sawai Amarjeet Kaur 《The Journal of comparative neurology》1997,378(3):379-388
The induction of postsynaptic structures by presynaptic terminals is suggested in a teleost brain. Neurons in the nucleus pretectalis superficialis pars magnocellularis (PSm) in the common carp are known to send fibers to the corpus mamillare (CM) and the nucleus lateralis valvulae (NLV). Individual axons of PSm neurons bifurcate (or give off an axon collateral), both of which reach the target areas in the CM and NLV. The morphology of horseradish peroxidase-labeled terminals in the CM and NLV appears quite different in light microscopy. Terminals in the CM appear as a fine network of beaded (2–4 μm in diameter) fibers, while those in the NLV are larger (8–12 μm in transverse diameter) and cup-shaped, partially enveloping the soma of individual NLV neurons. In electron microscopy, however, these synapses in the CM and NLV share several ultrastructural similarities. Small (0.2 to 0.4-μm thick, 0.4 to 0.7-μm long) spine-like protrusions arising from dendrites in the CM, and from cell bodies in the NLV, invaginate into the axon terminals, and the synaptic junctions are always formed at the base of the protrusion in both areas. Development of this unusual morphology is inferred to be directed from the presynaptic side. The morphological similarity of the spine-like protrusions to the “spinule,” which is thought to be formed in response to synaptic activation, is discussed. J. Comp. Neurol. 378:379–388, 1997. © 1997 Wiley-Liss, Inc. 相似文献
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1000.
Kikuko TAKETOMI Yoichi M. ITO Eriko TOKUNAGA Yuko O. HIRANO Yuriko FUJINO Akiko CHISHAKI 《Industrial health》2021,59(6):371
This study aimed to develop a questionnaire on the quality of working life among female medical and healthcare professionals and examine its validity and reliability. The questionnaire was developed from an item pool drawing on the literature. The four trait scales included 40 items, covering female-specific stress in continuing a career, stress of lifestyle in maintaining personal values, job satisfaction and social support network. The questionnaire’s validity and reliability were assessed using data from 1,784 female doctors, dentists, and nurses. Validity was examined using exploratory factor analysis on each trait for construct validity, and multitrait scaling analysis for convergent and discriminant validity. Reliability was tested using Cronbach’s alpha for trait subscales and scales. Exploratory factor analysis on each trait was convergent. One trait derived three subscales, and another two. The remaining two traits were convergent for one factor. Multitrait scaling analysis showed that all scales and subscales were independent. The questionnaire was therefore internally consistent and had construct validity. Cronbach’s alpha was 0.85 for the total and between 0.72 and 0.83 for the subscales. These results validate the four-trait combination questionnaire and suggest that it would be suitable for use in future research, perhaps in combination with other existing scales. 相似文献