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41.
Tokuo Ogawa Junichi Sugenoya Norikazu Ohnishi Keiko Natsume Kazuno Imai Yoshikazu Kandori Akira Ishizuka Atsushi Osada 《European journal of applied physiology》1993,67(4):354-359
Summary We have examined the nonparallel changes in tampanic membrane temperatures (T
ty) from the two ears in response to various changes in body and head positions. Upon assuming a lateral recumbent position, the T
ty on the lower side increased while that on the upper side decreased. Pressure application over a wide area of the lateral chest only caused inconsistent and obscure asymmetric changes in T
ty. A lateral flexion of the head with the subject sitting upright and a rotation of the head to the side in a supine position induced an increase in the T
ty on the lower side compared to that on the upper side. The temperature and blood flow of the forehead often decreased on the lower side and increased on the upper side, although such responses were not always concomitant with the asymmetric changes in T
ty. A dorsal flexion of the head with the subject in a reclining position caused a slight increase in the T
ty, whereas raising the head upright induced a slight decrease in them. Two additional experiments were carried out with single photon emission computed tomography using 99mTc-hexamethylpropyleneamine oxime as tracer, and a slight, relative decrease in counts was noted in the right hemisphere during rotation of the head to the right. These results would strongly suggest that unilateral increases and decreases in T
ty could have been caused by one-sided decreases and increases, respectively, in blood flow to the brain and/or the tympanic membrane, induced by a vasomotor reflex involving vestibular stimulation. 相似文献
42.
The relationship of gastrointestinal endocrine cells to gastric epithelial changes with special reference to gastric cancer. 总被引:4,自引:0,他引:4
Using advanced gastric adenocarcinoma and carcinoid as human material and gastric adenocarcinoma in rats induced by MNNG and in mice by localized X-irradiation of the stomach as experimental material, a pathological study was made on the relationship of gastric endocrine cells to gastric cancer. The results of the present study suggest that most of the endocrine cells in the cancer tissue are derived from the differentiation of cancer cells. Therefore, the following three may be given as the aformentioned relationship, that is, 1) carcinoid of endocrine cell origin, 2) endocrine cell carcinoma showing undifferentiated adenocarcinoma, and 3) endocrine cell cloning developed from the differentiation of cancer cell of adenocarcinoma. There is the possibility that most of 2) are of 3) origin and thus 2) and 3) should be discriminated from 1), having a functioning tumor in rare cases. The significance of reactive hyperplasia of endocrine cells in the non-metaplastic mucosa of the stomach around cancer and atypical epithelium is not yet determined, but that of EC cell seems at least to be related with the development of intestinal metaplasia in the gastric mucosa. 相似文献
43.
Makiko Itami Toshinao Takenouchi Junichi Tamaru Kenichi Harigaya Atsuo Mikata 《Pathology international》1991,41(4):277-285
It is well known that non Hodgkin's lymphoma (NHL) cells express various antigens which are normally involved in a variety of functions. In addition, NHL is diverse in its proliferative capacity. To investigate the relation between these factors and the clinical picture, 45 cases of NHL were studied by immunohistochemistry using snap-frozen materials obtained before therapy. Reactivities with 27 monoclonal antibodies were examined and the results were correlated with clinical findings. The expression of surface μ and CAM-1 in B-NHLs and CD25 in T-NHLs were significantly associated with bone marrow involvement. B-NHLs without expression of CD21(B2) and T-NHLs with CD25 were seen more frequently in cases with a LDH value of over 500 units/ml. The positivity rate of Ki-67 on B-NHLs was correlated with serum LDH value, NHL histologic classification, and overall survival. These data indicate that immunophenotyping and determination of the proliferative capacity of NHL are of value not only for confirmation of the histopathologic classification of the tumor but also for assessment of clinical behavior. 相似文献
44.
Reduced NR2A expression and prolonged decay of NMDA receptor-mediated synaptic current in rat vagal motoneurons following axotomy 总被引:1,自引:0,他引:1
Junichi Nabekura Tsuyoshi Ueno Shutaro Katsurabayashi Akiko Furuta Norio Akaike Masayoshi Okada† 《The Journal of physiology》2002,539(3):735-741
To elucidate characteristic changes in the N -methyl- d -aspartate (NMDA) receptor on neurons following axotomy, subunit expressions and functional features of the NMDA receptor were examined in the dorsal motor nucleus of vagus (DMV) of rats receiving vagal axotomy at the neck. Western blotting analysis demonstrated that the expression of NR2A decreased 2–3 days after in vivo axotomy, while expression of NR1 and NR2B, NR2C and NR2D subunits did not change significantly. To examine the functional changes, patch clamp recordings in whole-cell mode were employed on the axotomized DMV neurons identified by retrograde labelling with fluorescent dye. The amplitude ratios of ifenprodil-sensitive components of NMDA response and d , l -2-amino-5-phosphovaleric acid (APV)-sensitive evoked postsynaptic current increased after axotomy. In addition, APV-sensitive postsynaptic currents exhibited a longer decay time in identified axotomized vagal motoneurons than in control neurons. No significant differences in the current density of the NMDA response and the peak amplitude of APV-sensitive synaptic currents were observed between axotomized and intact DMV neurons. In conclusion, a decrease in NR2A expression results in the appearance of functional characteristics of the NMDA receptor predominantly containing the NR2B subunit. This might lead to a long-term increase of the susceptibility of neurons to excitotoxicity. 相似文献
45.
A 72-year-old man was admitted to our hospital complaining of diplopia and right exophthalmos. Craniography and CT scan showed thickening of the right orbital roof and no intracranial lesion. Total acid phosphatase and prostatic acid phosphatase were high. Bone scintigraphy revealed high uptake at that lesion and the right pelvis. Unroofing of the right orbit and opening of the optic canal were performed in order to reduce intraorbital pressure. Microscopic examination revealed a metastatic lesion of prostatic cancer. Postoperatively, the patient was treated with "Honvan" and the course has been good. 相似文献
46.
A 43-year-old female who had suffered from paranoid reaction attempted suicide with city gas. She was admitted to an emergency hospital in a comatose state, regained consciousness the next day and was discharged 12 days after. However, on the 21st day after the poisoning, behavioral anomalies and staggering appeared. She was readmitted into another emergency hospital with the diagnosis of an "interval" form of acute carbon monoxide poisoning. She was performed hyperbaric oxygen therapy 42 times until the 53rd day after the accident. Nevertheless, her symptoms did not improve and remained in a state like an apallic syndrome. With little promise of improvement, she was moved to our hospital, and hyperbaric oxygen therapy further continued for 40 times which resulted in a remarkable recovery. Repeat EEGs were performed. On the 32nd day, EEG showed an abnormality consisting of generalized delta waves. On the 56th day, the abnormal EEG improved slightly with more alpha activity. EEG was normalized 126 days after. The X-ray CT scan on the 32nd day revealed low densities in the bilateral globus pallidus and the deep white matters adjacent to the frontal horns of the lateral ventricle and in the semioval centers. On the 57th day, these low density areas were depicted more clearly by the X-ray CT scan, which became less marked on the 73rd day. MRI was performed 3 times.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
47.
Toshihiro Kawamoto Koji Matsuno Keiichi Arashidani Masahiro Yoshikawa Fujio Kayama Yasushi Kodama 《Archives of environmental contamination and toxicology》1993,25(4):534-538
The personal exposure to NO2 generated from various heaters and cooking stoves were studied, using 85 university students. The students attached NO2 filter badges to their chests or collars and wrote down the period of time for heating and cooking for 1 week. Types of heaters and smoking habits were described through a questionnaire. The urinary hydroxyproline/creatinine ratio (HOP/C) was examined as a biomarker for health effects. The outdoor NO2 concentration during the study period was 13.5–13.7 g/m3. Smoking and the usage of electric heaters did not affect the exposure to NO2. Exposure increased according to the length of time kerosene heaters or oil fan heaters were used. The NO2 concentration during the heating by a kerosene heater and an oil fan heater was calculated to be 219 and 474 g/m3, respectively. The correlation between the period of cooking and personal exposure was also observed. The NO2 levels during cooking were calculated to be 290 g/m3. Using these calculated values of NO2 concentration, it is possible to presume the personal exposure levels from the length of time heaters and cooking stoves are used even if the subjects do not attach the filter badges. Neither smoking nor exposure to NO2 were associated with the increase of urinary HOP/C. 相似文献
48.
Opsonic function and concentration of human serum ficolin/P35. 总被引:6,自引:0,他引:6
Collectins, C-type (Ca2+-dependent) animal lectins with both collagenous and carbohydrate recognition domains, function as opsonins against pathogens. We previously described an N-acetylglucosamine (GlcNAc)-binding lectin (ficolin/P35) with a collagen- and a fibrinogen-like sequence present in human serum. In this report we show that ficolin/P35 can serve as an opsonin and enhance the clearance of pathogens having surface GlcNAc. Ficolin/P35 bound to an Ra chemotype strain of Salmonella typhimurium (TV119) which has an exposed GlcNAc at the non-reducing termini of the polysaccharide. On the other hand, ficolin/P35 did not bind to LT2, a smooth type strain of S. typhimurium with additional O-polysaccharides covering GlcNAc. Ficolin/P35 enhanced the uptake of TV119 by monocytes or polymorphonuclear leukocytes but had no opsonic activity towards LT2. These results suggest that, like collectins, ficolin/P35 is a collagenous lectin which has a role in innate immunity against certain pathogenic organisms by acting as an opsonin. We prepared monoclonal antibodies against ficolin/P35 and developed an enzyme-linked immunosorbent assay (ELISA) for measuring ficolin/P35 concentrations in humans. The mean serum concentration of ficolin/P35 from 130 normal individuals was estimated to be 13.7 microg/ml. 相似文献
49.
The purpose of this study was to test the validity of the steroid carcinogenesis hypothesis by comparatively investigating the endocrinological and epidemiological aspects of cancers of the breast, uterine cervix, endometrium, stomach, esophagus and ovary. The emphasis of this study was placed on the extraction of the information on the topological feature of oncogene activation-tumor suppressor gene inactivation for each of 6 neoplasias using the data stock of the age-adjusted incidence rates (AAIRs) of 19 neoplasias from 47 population units of the world. Our investigation was started on the basis of the recognition that the world statistics data of cancer risk should include information on the interaction of oncogene activation-tumor suppressor gene inactivation for each human neoplasia, and that the sophisticated application of statistical analysis technics may allow us to assess separately the implications of oncogene activation and tumor suppressor gene inactivation in the genesis of a given neoplasia. In designing mathematical strategies, we had in mind the premise that oncogene activation and tumor suppressor gene inactivation represent 2 distinct entities in the world of chemistry, and that they should have each their own equilibrium models with 2 distinct equilibrium points. The details of the mathematical principles and procedures are presented in the text. The results were as follows: i) There was a good agreement of results between the observed value and the expected value of thermodynamics as regards the location of the equilibrium point in both instances - a finding to support the validity of our mathematical strategies. ii) One of our mathematical strategies (the use of the original coordinates and its variant coordinates in parallel) was found to be useful for assessing separately the implication of oncogene activation (the original coordinates) and that of tumor suppressor gene inactivation (the variant coordinates). iii) The correlation study of the endocrinological data with the epidemiological data in breast cancer strongly suggests the possibility that sex steroid may play a cardinal role in the oncogene activation at the initiation step of breast carcinogenesis. iv) Evidence is available to indicate that glucocorticoid under certain circumstances may play a crucial role in the process of tumor suppressor gene inactivation at the promotion step of breast carcinogenesis. v) The philosophical distinction between the steroid carcinogenesis theory and the random mutation criminal theory of carcinogenesis is discussed in the light of recent information on chemical carcinogenesis. 相似文献
50.
Junichi Okada Hiroshi Oonishi Kyosan Yoshikawa Keiko Imaseki Kimiichi Uno Jun Itami Noboru Arimizu 《Annals of nuclear medicine》1994,8(2):109-113
To evaluate positron emission tomography with18F-fluorodeoxy glucose (FDG-PET) as an diagnostic tool to determine tumor viability after anticancer therapy, fourteen patients were examined by FDG-PET after the end of the treatment. The lesions with residual viable tumor cells showed higher uptake of FDG than surrounding normal soft tissue. The lesions, in which tumor viability was lost or very low, showed higher uptake of FDG in four cases and similar uptake to normal soft tissue in three cases. The residual increased uptake of FDG was considered to be caused by remaining tumor cells and/or inflammatory reaction to anticancer treatment. FDG-PET after anticancer treatment should be interpreted by considering the reaction due to the treatment and the partial volume artifact of PET caused by the limited spatial resolution. 相似文献