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S Nomiyama B Nishioka T Ishii K Nakamura S Majima 《The Japanese journal of surgery》1981,11(5):346-352
Since somatostatin is a local hormone controlling gastric acid secretion and gastrin release, quantitative histopological distribution of the G-cells and D-cells in the canine whole stomach was investigated by the specific immunoperoxidase staining technique. The G-cells were identified only in the pyloric antrum and the estimated total number of G-cells was 15.5 X 10(6) cells. Most of the D-cells were also found in the pyloric antrum but a few were found scattered diffusely throughout body and fundus of the stomach. The estimated total number of D-cells was 11 X 10(6) cells in the pyloric antrum and 4 X 10(6) cells in the corpus and fundus. The G-/D-cell ratio in the antrum was 1.4:1. The number of G-cells as well as D-cells per unit mucosal surface area was significantly higher on the greater curvature and the proximal part of the antrum than on other areas of the antrum. Thus, the pattern of distribution in G-cells was similar to that of D-cells and there was a highly significant correlation between G- and D-cells per unit mucosal surface area. It would appear that under normal conditions, the number of G- and D-cells in the antrum are in good balance and may play an important role in the control mechanisms related to gastric secretion. 相似文献
3.
H Majima M Urano M Sougawa J Kahn 《International journal of radiation oncology, biology, physics》1992,22(5):1019-1028
Radiation and thermal sensitivities, and cell doubling times (Tds) of C3Hf/Sed mouse FSa-II cells recurring after a heavy irradiation were examined in vitro. Tumors in the leg were irradiated with gamma-rays and observed for late recurrence (in vivo clones), or removed immediately after irradiation and single cell suspensions were plated for colony formation (in vitro clones). Five subclones were selected from original cells in vitro. Survival curves were fitted to the multi-target and linear quadratic models. Surviving fractions at 2 (SF2) and 10 Gy (SF10) irradiations, and those at 30 and 60 min heatings at 44 degrees C (SF30 and SF60), were obtained for each clone. Although, Tds of subclones were slightly longer than those of the parental cells, those of recurrent clones were prolonged substantially with an exception of one cell line. Radiosensitivities of FSa-II parental cells tested in vitro and in vivo were equally radioresistant. Thermal sensitivities of parental cells tested in vitro and in vivo were also identical. All subclones were more radiosensitive compared to the parental cells. The in vitro recurrent clones showed smaller D0 (radiation dose to reduce survival from S to S/e in the exponential portion of survival curve) than the D0 of the parental cells. The SF2 values of four in vitro recurrent clones were greater than that of the parental cells whereas those of two lines were smaller. It was of interest that the in vivo recurrent tumor cells showed a wide variation in the radiation sensitivity. Among 9 tumor cell lines examined, 4 lines were more sensitive and 4 were more resistant compared to the original. FSa-II subclones as well as both in vitro and in vivo recurrent clones showed a wide variation in thermal sensitivity. No consistent changes in the shoulder or in the slope were found. The SF30 or SF60 showed that 5 out of 9 in vivo recurrent clones and 4 out of 9 in vitro clones were more resistant compared to the original cells. No correlation was observed between thermal and radiation sensitivities. The Td was not related with radiation or thermal sensitivity. 相似文献
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BACKGROUND: A simple, rapid, inexpensive method for measuring the flow in a
patient's vascular access would permit routine monitoring during
haemodialysis, and hence provide information of access graft deterioration
sufficiently early to increase the success of minimally invasive remedial
procedures. This paper reports the validation of such a method in animals.
METHODS: A PTFE graft was implanted in sheep between the carotid artery and
the jugular vein. While the sheep was under general anaesthesia and on an
haemodialysis circuit, ultrasound velocity in its blood was perturbed by
the injection of a 5-10 ml bolus of isotonic NaCl. The pump tubing flow was
measured by a transit-time blood flow meter. This flow was combined with
the areas of perturbation generated by the injection before and after
mixing in the access flow to estimate graft flow. The calculated graft flow
was compared to flow measured directly by a transit-time probe on the same
carotid artery. RESULTS: Over a 10-fold range, 120-1260 ml/min, graft flow
measured by ultrasound velocity dilution agreed well with graft flow
measured directly with a scatter of 76 ml/min about the regression line.
CONCLUSION: Ultrasound velocity dilution provides a method for measuring
flow in the graft accurate enough for clinical evaluation of patients on
dialysis.
相似文献
7.
The occurrence of late asthmatic response (LAR) is effectively prevented by corticosteroids, but not all by beta-adrenergic drugs. LAR is considered to be of great clinical and therapeutic importance and to be involved in the progression of bronchial asthma into a severe or even an intractable form. However the exact mechanism of the occurrence of LAR remains obscure in many respects. LAR is believed to be due to type I allergy. In guinea pigs, a positive bronchial inhalation challenge following passive sensitization with allogeneic antibody does not induce LAR or eosinophilic infiltration of lung tissue. This experimental fact led us to surmise that LAR would seem likely to be elicited in passively sensitized animals if pronounced eosinophilic infiltration can be induced concurrently and to conduct an experiment with conjoined inhalation of platelet activating factor (PAF). PAF, which has a chemotactic activity for eosinophils, was administered to passively sensitized animals in attempt to examine a role of eosinophils in LAR. A goodly number of animals developed LAR on additional PAF inhalation. These animals, when compared with those without LAR, showed a significantly larger proportion of eosinophils in BALF (p less than 0.05) with an upward tendency for the proportion of neutrophils. Histologically, there was noted a striking association between LAR and eosinophilic infiltration of the bronchial submucosa. These results suggest that anti-IgE antibody is deeply involved in the elicitation of LAR, stressing the importance of eosinophilic infiltration. 相似文献
8.
Evidence for the involvement of a plasma kallikrein-kinin system in the immediate hypotension produced by endotoxin in anaesthetized rats. 总被引:4,自引:4,他引:0 下载免费PDF全文
M. Katori M. Majima R. Odoi-Adome N. Sunahara Y. Uchida 《British journal of pharmacology》1989,98(4):1383-1391
1. In vitro incubation of normal rat plasma with endotoxin from E. coli (3-10 mg ml-1) in the incubation mixture) caused a dose-dependent increase in levels of free kinin and plasma kallikrein in the presence of o-phenanthroline, together with a mirror-image, dose-dependent decrease in the residual levels of the precursors, plasma prekallikrein and high-molecular-weight kininogen. Low-molecular-weight kininogen levels were not modified. 2. Intravenous injection of endotoxin (3-30 mg kg-1) into the femoral vein of anaesthetized rats resulted in dose-dependent hypotension. In blood collected up to 15 min after injection, the levels of prekallikrein and high-molecular-weight kininogen in plasma were decreased while levels of the active forms, plasma kallikrein and free kinin, showed a transient increase in the blood 1 min after administration of endotoxin. 3. A degradation product of bradykinin, des-Phe8-Arg9-bradykinin, as measured by a newly developed enzyme immunoassay, was detectable up to 5 min after administration of endotoxin. 4. Intravenous infusion of soybean trypsin inhibitor inhibited both the formation of bradykinin and des-Phe8-Arg9-bradykinin and the initial hypotension. 5. It can be concluded from our results that plasma prekallikrein is activated in the blood immediately after administration of endotoxin to rats and that bradykinin is a major cause of the immediate hypotension. 相似文献
9.
Tissue specimens from patients with the scirrhous type of gastric carcinoma were stained using the peroxidase-antiperoxidase (PAP) method. Nine out of thirty-seven specimens (24 per cent) showed positive estrogen staining, and here tissues from male or older patients were usually stained. Cumulative survival rate in patients whose tissue showed a positive estrogen staining was higher than that in case of a negative estrogen staining. Four out of thirty-one specimens (13 per cent) stained positively for progesterone, all four patients being male. These results suggest that estrogen and progesterone may relate to the growth of the scirrhous type of gastric cancer. 相似文献
10.
Information concerning surgical treatment of adult patients with chronic sinusitis was obtained through questionnaires from 434 hospitals in Japan. The hospitals were authorized for an in-service otorhinolaryngological training institute by the Oto-Rhino-Laryngological Society of Japan. The questionnaires were sent to the hospitals in December, 1989, and answers were obtained from 370 hospitals within 2 months, an 85.3% response rate. The following results were obtained. In 96.2% of the hospitals, permaxillary sinus surgery was performed on patients whose maxillary and ethmoid lesions were severe. With moderate lesions of both the maxillary and ethmoid sinuses, permaxillary sinus surgery and endonasal sinus surgery were performed in 76.0% and 24.9%, respectively. Application of an endoscope for sinus surgery was reported by 89 hospitals. In January, 1990, a further survey was sent to the 89 hospitals where endoscopic sinus surgery was performed. Questionnaire responses were obtained from 75 hospitals. Rigid endoscope was used most frequently and operative microscope was also used. Endoscopy was applied to all of the sinus surgery procedures in 21.6%, and to a portion of the procedures in 74.3% of the hospitals. About 50% of the hospitals performed endoscopic surgery in fewer than 30% of sinus surgery cases. When questioned as whether endoscopic surgery had been successful, 42.6% said yes, 10.7% said no, and 42.6% were unsure. 相似文献