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81.
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Kenji Wakabayashi Kazuo Kawasaki Daizo Yonemura Kiyohiko Yamazaki 《Documenta ophthalmologica. Advances in ophthalmology》1986,63(4):383-388
We previously reported the hyperosmolarity response (a decrease of the ocular standing potential by hyperosmolarity) as a new clinical test of the retinal pigment epithelium (RPE) activity. In the present study a hypertonic solution (Fructmanit, 1.4 × 103 m0sm/1) was intravenously injected for 20 min in proportion to a subject's total blood volume (TBV). At the injection speed of 5, 10, and 15% of the subjects' TBV per hour the mean amplitude of the hyperosmolarity response in normal subjects was 19.7, 30.1 and 36.4% respectively. The amplitude of the hyperosmolarity response depends on the logarithm of the dose of the hypertonic solution within the range of the dose tested.We previously found that hyperosmolarity suppresses the light rise. The present study investigated this suppressive effect in a quantitative manner. The light rise (a full-field illumination of 1.2 × 103 cdl/m2) was dose-dependently suppressed by Fructmanit. The mean of the light rise to dark trough ratio in normal subjects was 1.81 with no osmotic stress, and 1.64, 1.41 and 1.29 respectively at the injection speeds of 5, 10, and 15%. The suppression of the light rise by hyperosmolarity is compatible with the view that the hyperosmolarity response and the light rise share the basal membrane of the RPE as the main site of their generation. 相似文献
84.
Chojiro Yamashita Satosi Tobe Hidehiro Yamamoto Hidefumi Oobo Hiroomi Nakamura Kazuo Nakamura 《Surgery today》1994,24(10):906-910
This study examines the pulmonary hemodynamics during reimplantation and rejection following unilateral lung transplantation in dogs. Nineteen mongrel dogs were divided into three groups according to the method of treatment used: group 1 (n = 6) underwent modified autotransplantation of the left lung; group 2 (n = 6), allotransplantation without immunosuppression; and group 3 (n = 7), allotransplantation with immunosuppression. The pulmonary arterial blood flow and ventilation scores, assessed by chest X-rays, were measured for 2 weeks postoperatively. Pulmonary blood flow to the transplanted lung decreased slightly in group 1, whereas in group 2, it decreased sharply from the 3rd postoperative day (POD) and was almost completely absent by the 14th POD. In group 3, it decreased by 28% on the 1st POD but recovered gradually to 37% by the 14th POD. Ventilation scores were the same among the three groups on the 1st POD but in group 2, they decreased rapidly from the 3rd POD. This change correlated well with that of the pulmonary arterial (PA) flow, although the ventilation score changed after the PA flow did. In conclusion, rejection was reflected earlier and more distinctly by the changes in PA flow than by chest X-rays. 相似文献
85.
S Shinozaki Y Matsuzawa S Yoshikawa K Fujimoto S Yamaguchi K Harada K Kubo T Kobayashi M Sekiguchi 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(8):954-962
The authors studied the effects of natural panting frequency (NF) and the cheek support on the plethysmographic measurement of thoracic gas volume (TGV) in 8 normal subjects (non-smokers) and 46 patients with chronic obstructive pulmonary disease (COPD). The patients were divided into 2 groups according to the degree of airway obstruction (group I; specific airway conductance (SGaw) greater than 0.1 (n = 18), group II; SGaw less than 0.1 (n = 28)). TGV was measured with a pressure-type body plethysmograph (BP). NF was 2.00 +/- 0.43 Hz (mean +/- SD) in control subjects, 1.92 +/- 0.78 Hz in group I, and 1.39 +/- 0.59 Hz in group II, respectively, indicating lower NF in the patients with severe airway obstruction. In control subjects and group I, the differences between TGV at NF and at 0.5-1.0 Hz (TGVNF-TGV1.0) were -0.01 +/- 0.07L, and -0.06 +/- 0.16L, respectively, and cheek support did not alter the difference. On the other hand, in group II, the difference was slightly larger than other groups in spite of the lower NF, and this overestimation was abolished by cheek support (0.13 +/- 0.25L-----0.06 +/- 0.27L, p less than 0.05). These results suggest that, in patients with severe airway obstruction, TGVNF may be overestimated even if NF is relatively low. This overestimation may be mainly due to the extrathoracic airway compliance including the cheek. 相似文献
86.
Tadaki Yasumura MD Toshikazu Akami Manabu Mitsuo Takahiro Oka Kazuo Naitoh Takara Yamamoto Hideo Honjyo Hiroji Okada 《Surgery today》1990,20(4):369-375
The ovarian and pituitary functions of 64 operable breast cancer patients undergoing adjuvant therapy with cytotoxic chemotherapy
and/or tamoxifen were investigated. The post menopausal patients, divided into 3 treatment groups, one with tamoxifen alone,
one with tamoxifen and chemotherapy and the other with chemotherapy alone had serum estradiol 17-β (E2) and progesterone levels
lower than the evaluable limits. Although there was no significant difference in the level of estrone sulfate (E1-S) between
these three groups, the level of lutainizing hormone (LH) and follicle stimulating hormone (FSH) in the patients treated with
tamoxifen alone and tamoxifen and chemotherapy were significantly lower than those treated with chemotherapy alone. The decrease
in gonadotropin levels induced by tamoxifen treatment was reversible as it appeared after the initiation of tamoxifen and
recovered after its cessation. In the premenopausal patients, a group treated with tamoxifen and chemotherapy had significantly
higher E1-S, E2 and progesterone levels and significantly lower gonadotropin levels than a group treated with chemotherapy
alone or one treated with a cyclophosphamide regimen. These increases in the levels of estrogen and progesterone were also
reversible, and induced by tamoxifen. Thus, adjuvant endocrinochemotherapy causes profound alteration in the hypothalamo-pituitary-ovarian
axis and therefore, monitoring a variety of hormonal levels is thought to be necessary for assessing the consequences of adjuvant
therapy in breast cancer patients, especially in premenopausal patients using tamoxifen. 相似文献
87.
Hidehito Matsuoka Wataru Nishio Toshihiko Sakamoto Hiroaki Harada Noriaki Tsubota 《European journal of cardio-thoracic surgery》2004,26(3):480-482
OBJECTIVE: To predict accurate morbidity after lung resection using treadmill exercise test. METHODS: A total of 130 patients (108 men and 22 women, with mean age 67.1+/-11.4 years (range, 34-78 years)) of 1129 patients underwent standard lobectomy were performed both treadmill exercise test and spirometry preoperatively. We measured maximum oxygen uptake/body weight (VO2max/BW) and change in arterial blood oxygen pressure from rest to symptom-limited maximum loading (delta aPaO2) and calculated exercise-induced hypoxemia (delta PaO2/delta VO2/BW), and retrospectively compared these parameters for patients with and without complications. RESULTS: There were five patients with severe postoperative complications, including three requiring use of a respirator, two with home oxygen therapy. %Vital capacity, VC (%, 80.2+/-13.2 vs. 92.5+/-20.9, P=0.026), delta PaO2 (Torr, -29.3+/-4.3 vs. -13.2+/-10.8, P=0.0004), VO2max/BW (ml/min/kg, 16.5+/-2.9 vs. 20.6+/-5.1, P=0.018) and delta PaO2/delta VO2/BW (Torr/ml/min/kg, -1.98+/-0.26 vs. -0.57+/-0.47) were significantly associated with worse outcome. All the five patients with complications had delta PaO2/delta VO2/BW<-1.7. CONCLUSIONS: Treadmill exercise testing is a good method for assessment of cardiopulmonary reserve. Limited resection must be performed if delta PaO2/delta VO2/BW is under -1.7. 相似文献
88.
89.
90.
Hiroko Sasahara Susumu Sueyoshi Toshiaki Tanaka Hiromasa Fujita Kazuo Shirouzu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2004,52(5):231-239
Objective: The purpose of this experimental study was to investigate whether aortic stent grafting can be applied to the treatment of
an esophageal cancer involving the thoracic aorta. Methods: The canine thoracic aorta was partially resected without aorta being clamped after emplacement of an endovascular stent graft.
Study I; The aortic whole layer of 1 cm in length and 1/4 of the circumference was resected and was covered by a free fascia
patch of the abdominal rectal muscle immediately after stent graft placement. Study II; The aortic adventitia and the outer
half of the media of the same size was resected on day 3, 7,14, 21, and on day 28, after the stent graft placement. The resected
portion was covered by the free fascia patch in half experimental dogs, and was uncovered in the others. Study III; The aortic
adventitia and the outer half of the media of 1 cm in length and 1/2 of the circumference was resected and was uncovered on
day 7 after stent graft placement. Histological examinations were performed on day 28 and at one year after aortic resection.
Results: The aortic wall could be resected in all cases with no complication, except in resection of 1/2 the circumference where the
aorta had become narrow. There was no difference in healing of the resected portion of the aorta between with and without
fascia covering. Conclusion: An aortic endovascular stent graft could be applied to surgery for an esophageal cancer involving the aorta. 相似文献