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Kanji Takeo Eric Virtudazo Misako Ohkusu Susumu Kawamoto Shoko Ito-Kuwa Sigeji Aoki 《Nippon Ishinkin Gakkai Zasshi》2006,47(4):257-262
In Cryptococcus neoformans the DNA content of cells having tiny buds varied rather widely, depending on growth phases and strains used. Typically, buds of C. neoformans emerged soon after initiation of DNA synthesis in the early exponential phase. However, bud emergence was delayed to G2 during transition to the stationary phase, and in the early stationary phase budding scarcely occurred, although roughly half of the cells completed DNA synthesis. The timing of budding in C. neoformans was shifted to later cell cycle points with progression of the growth phase of the culture. Similarly, a deficit in oxygen was demonstrated to delay the timing of budding, prolong the G2 phase and cause accumulation of cells after DNA synthesis, but before commitment to budding. The C. neoformans homologue of the main cell cycle control gene CDC28/Cdc2 was isolated using degenerate RT-PCR. The full-length coding region was then amplified using primers to target the regions around the start and stop codons. The gene was called CnCdk1 and was found to have high homologies to S. cerevisiae CDC28 and S. pombe cdc2. To determine its function, its ability to rescue S. cerevisiae cdc28-temperature sensitive mutants was tested. S. cerevisiae cdc28-4 and cdc28-1N strains transformed with the pYES2-CnCdk1 construct exhibited growth at the restrictive temperature. Results of the sequence analysis and the ability of CnCdk1 to complement the S. cerevisiae cdc28-ts mutations support its assumed role as the CDC28/cdc2 homologue in C. neoformans. 相似文献
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The effects of pH on the formation and dissociation of the complex of trypsin and PSTI was investigated using pancreatic juice of two patients. Pancreatic juice was eluted from a Sephadex G100 column with the buffer in different pH values, and the trypsin inhibitory activity in the eluate was measured. Under alkaline and neutral conditions, the complex of PSTI and trypsin was observed, while in acidic condition, dissociation of the complex was occurred. Molar ratio of PSTI and trypsin in the complex was found to be one mole/one mole. Human serum, alpha 1-antitrypsin, and alpha 2-macroglobulin dissociated the complex of PSTI and trypsin. 相似文献
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H Nakamura T Moroji H Nakamura S Nohara A Okada 《Nihon eiseigaku zasshi. Japanese journal of hygiene》1992,46(6):1095-1103
In order to clarify the involvement of cerebral 3,4-dihydroxyphenylacetic acid (DOPAC) and vasoactive intestinal polypeptide (VIP) in whole-body vibration stress, DOPAC and VIP-like immunoreactivity (VIP-LI) in various discrete brain regions of rats exposed to whole-body vibration (4G, 20 Hz, 90 min) were assayed. The results showed that the whole-body vibration increased the DOPAC level in the frontal cortex and nucleus accumbens, but did not induce a concurrent change of VIP-LI in these regions. VIP-LI was significantly increased in the amygdala, and decreased in the hippocampus, accompanied by no significant change of DOPAC. These results show that whole-body vibration affects cerebral VIP neuron systems in addition to its nonspecific action, i.e. the activation of mesofrontal and mesoaccumbens dopamine neuron systems. It is assumed that the amygdalofugal VIP neuronal system is involved in the regulation of hypothalamic and pituitary hormone secretions, and that VIP in the hippocampus plays a part in modulating the blood circulation in the cortex in whole-body vibration stress. 相似文献
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Eduardo Kazuo Sannomiya Jun-ichi Asaumi Kanji Kishi Gisele da Silva Dalben 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(2):e41-e44
Dens invaginatus is a developmental variation resulting from an alteration in the normal growth pattern of the dental papilla. Synonyms of this disturbance include dens in dente, invaginated odontome, tooth inclusion, and dentoid in dente. Radiographically, it is observed as infolding of a radiopaque ribbon-like structure, with equal density as enamel, extending from the cingulum into the root canal and sometimes reaching the root apex, assigning the appearance of a small tooth within the coronal pulp cavity. This article presents 2 case reports. The first describes an 8-year-old girl with dens invaginatus in a mesiodens; the second report describes a 16-year-old boy presenting with 2 mesiodens, both associated with dens invaginatus. 相似文献
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Takahiko Misao Kanji Minamoto Hideharu Nakano Masataka Yamane Yosuke Yamamoto Katashi Satoh 《General thoracic and cardiovascular surgery》2005,53(6):309-312
A 64-year-old female was found to have localized ground-glass opacity (GGO) in the middle lobe on a chest computed tomography (CT) for screening. Middle lobectomy with video-assisted thoracoscopic surgery (VATS) was undertaken, and pathological diagnosis was a bronchioloalveolar carcinoma (BAC) in stage IA. A follow-up CT a year following the surgery revealed localized GGO in area S6 of the left lung. However, it disappeared during the gravitation-dependent gradient in the observation period. The patient was scanned again under prone position to exclude the gravitational effect, resulting in definite detection of the GGO. Left extended S6 segmentectomy with VATS was performed, and pathological diagnosis was a BAC in stage IA. As GGO existing in a gravitation-dependent area may be masked by the gravitation-dependent density, a change of the scanning position may lead to a proper detection of the tumor for the diagnosis of BAC. 相似文献
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N Yoshimura T Asada H Matsuda H Nohara T Higami M Nishiwaki N Mukohara M Chibana K Ogawa 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(2):157-159
A 17-year-old male patient with Marfan syndrome was admitted due to recurrent bilateral pneumothorax which had recurred totally 11 times during the past 3 years. For the treatment of obstinately continuing right pneumothorax resection of bullae in combination with pleuropexy using OK 432 was effective. Two months thereafter Bentall operation with a composite graft consisting of a woven Dacron tube and a Bj?rk-Shiley 27 mm aortic valve prosthesis was performed for his anuloartic ectasia. Left pneumothorax recurred 2 weeks after Bentall operation. But it was treated successfully with OK 432 injection into the left pleural cavity. Now, he is doing well as a student. 相似文献