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81.
82.
M Yamazato K Kimura H Yoshino M Murr D Ellsbury R T Soper 《Journal of pediatric surgery》1992,27(6):691-695
In previous reports, anastomosis has been shown to disrupt the myoelectric activity of the bowel. However, these studies have failed to delineate the role of the extrinsic nerves. Using an isolated bowel segment (IBS) and an amesenteric bowel segment (ABS), motility was evaluated by myoelectric recording across a bowel anastomosis. Ten rats were divided equally into the experimental group with the IBS and the control group with the ABS. In the IBS group, an 8-cm segment of jejunum was divided, reanastomosed, and coapted to the liver margin (Iowa model II). In the ABS group, an 8-cm segment of jejunum was coapted to the liver margin without disruption of bowel continuity (Iowa model II variant). Two weeks later, bipolar electrodes were implanted in the IBS and ABS, and normal jejunum in both groups. Mesenteric division (MD) was performed 4 weeks later to eliminate extrinsic innervation. Myoelectrical recordings were taken 2 weeks before and after MD. In the control group with IBS, incoordination in the propagation of the migrating motor complex (MMC) and reduction in the frequency of slow waves (FSW) were observed across the anastomosis and were unchanged by MD. In the control group with the ABS, the MMC and FSW were identical to that in the normal jejunum and were unaffected by MD. In both groups postprandial inhibition of the MMC was the same as in the normal jejunum and was unaffected by MD. This study confirms that incoordination in propagation of the MMC and reduction in FSW occur across a bowel anastomosis, and elimination of extrinsic innervation does not affect the autonomy of these changes.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
83.
Wataru Kimura 《Journal of hepato-biliary-pancreatic sciences》2003,10(2):156-162
The differences and similarities between intraductal papillary mucinous tumor (IPMT) and mucinous cystadenoma or carcinoma (mucinous cystic tumor; MCT) of the pancreas have been noted. The similarities include: (1) both tumors originate from pancreatic duct cells, (2) massive mucin production is found in both tumors, and (3) papillary projection is a common histological characteristic. However, there are also many differences. IPMT is most frequently found in men in their sixties, and originates in the head of the pancreas, with 62% (123/199) of tumors reported to be found in the head of the pancreas. This tumor sometimes spreads throughout the entire pancreas. The tumor itself basically is of the dilated pancreatic duct type, and the prognosis is generally good. In contrast, MCT frequently develops in women in their forties. This tumor is usually large, round, and almost totally encapsulated by fibrous tissue, with no communication with the pancreatic duct. The tumor histologically has an ovarian-like stroma. It most often develops in the body or tail of the pancreas. Invasion is often present and the operative prognosis is not good. IPMT resembles the shape of a bunch of grapes and MCT resembles that of an orange. From the differences between these two types of tumors, they are classified into different categories. With regard to therapeutic strategies for MCT, the tumor should be resected with lymph node dissection immediately when it is detected. In contrast, some patients with branch-type IPMT can be followed without surgical procedures. Because IPMT shows good prognosis and little tendency for infiltration, some kinds of organ-preserving procedures would be possible for some patients with this tumor. Such organ-preserving procedures are: duodenum-preserving pancreas head resection, spleen-preserving distal pancreatectomy with conservation of the splenic artery and vein, and so on. 相似文献
84.
Tetsuhiko Nagao Seizo Sadoshima Takao Ishitsuka Kenji Kusuda Osamu Shiokawa Setsuro Lbayashi Masatoshi Fujishima 《Clinical and experimental pharmacology & physiology》1992,19(7):489-493
1. The effects of acute bilateral superior cervical ganglionectomy on cerebral blood flow and metabolism were investigated in stroke-prone spontaneously hypertensive rats (SHRsp), before and during cerebral ischaemia. 2. The resting cerebral blood flow was comparable between the control and denervated animals. 3. There was no significant difference in cerebral blood flow or concentration of tissue energy metabolites (adenosine triphosphate [ATP], lactate and pyruvate) between the sham-operated control and denervated animals during ischaemia. 4. The results suggest that sympathetic innervation of cerebral vessels originating from superior cervical ganglia may not play a major role in the progression of cerebral ischaemia in SHRsp. 相似文献
85.
Shigeharu Kimura Yoshimi Ohshige Liping Lin Tadashi Okumura Chizuko Yanaihara Noboru Yanaihara† Yahe Shiotani 《Journal of neuroendocrinology》1994,6(5):503-507
The localization of pituitary adenylate cyclase-activating polypeptide (PACAP) in the hypothalamus-pituitary system in rats was examined in light and electron microscopic immunocytochemistry using a specific antiserum to synthetic PACAP 1–38 (R0831). In light microscopic study, intensely PACAP-immunostained perikarya were observed in the supraoptic and paraventricular magnocellular nucleus in the hypothalamus. In the median eminence, many immunoreactive nerve fibers were observed in the internal layer, but a few immunoreactive terminals were noticed in the external layer. In the pituitary gland, numerous immunoreactive nerve fibers were observed in the posterior lobe. In the intermediate lobe, moderately immunostained cells were observed, but in the anterior lobe no immunostained cells were noticed. In electron microscopic study, PACAP-immunoreactivity was examined by avidin-biotin peroxidase complex method. In the perikarya of the supraoptic and paraventricular magnocellular nucleus, DAB-reaction products were distributed diffusely in the cytoplasmic matrix, frequently attaching to the rough-surfaced endoplasmic reticulum. In the nerve terminals of the posterior lobe, reaction products were observed among the secretory granules, but sometimes upon them. In the cells of the intermediate lobe, reaction products were also distributed in the cytoplasmic matrix. 相似文献
86.
Toshifumi Gabata Osamu Matsui Masumi Kadoya Jun Yoshikawa Kazuhiko Ueda Yasuhiro Kawamori Tsutomu Takashima 《Journal of magnetic resonance imaging : JMRI》1997,7(5):855-857
The purpose of this study was to determine the relationship between segmental hyperintensity of the liver on T1-weighted images and segmental cholestasis in patients with obstructive jaundice. T1-weighted and T2-weighted MR images were obtained of 73 patients with obstructive jaundice caused by various diseases. Fat-suppressed T1-weighted images were also obtained of 10 patients. Eleven patients with segmental intra-hepatic bile duct dilatation (cholestasis) showed segmental hyperintensity on T1-weighted images and/or fat-suppressed T1-weighted images and no signal intensity difference on T2-weighted images. Sixty-two patients with widespread intrahepatic bile duct dilatation showed no intensity difference on T1-weighted and T2-weighted images (P < .01). Segmental hyperintensity on T1-weighted images was correlated with intrahepatic cholestasis. 相似文献
87.
Naoya Emoto Eiji Ohmura Osamu Isozaki Toshio Tsushima Kazuo Shizume Hiroshi Demure 《Clinical endocrinology》1991,34(5):377-382
In order to study the mechanism of GH secretion from somatotroph adenoma cells, we have compared the effect of 12–O-tetradecanoyl phorboi-13-acetate (TPA) with that of growth hormone releasing factor (GRF) on GH secretion from human somatotroph adenoma cells cultured in monolayer. Pituitary adenoma cells were obtained from 13 patients with acromegaly undergoing surgery. On the 7th day of culture, the cells were exposed for 2 h to secretagogues. All 13 adenoma cell cultures (100%) responded to TPA (1·6–16·0 nmol/I) with a two- to six-fold increase in GH release (240·37% Increase of control: mean±SE). The response was detectable within 10 min, and was maximal at 2 h. Phosphollpase C (7·7 mmol/I) also stimulated a two-to ten-fold Increase In GH release in all four adenomas examined (100%). GH release was stimulated by GRF (2·0 nmol/I) in eight out of 12 adenoma cells (67%), but the magnitude of the responses to GRF (60·18% Increase of control: mean ± SE) were much smaller than that of TPA. Five out of 13 adenomas secreted detectable amount of PRL Into the medium and these five adenomas (100%) responded to TPA (16·0 nmol/I) with a two- to six-fold Increase. These observations indicate that the activation of protein kinase C is the consistent stimulator in GH and PRL secretion In human somatotroph adenoma cells. However, It is not determined whether the protein kinase C 相似文献
88.
Y Nomura S Miura H Koyama K Enomoto F Kasumi H Yamamoto M Kimura T Tominaga H Iino T Morimoto 《Cancer》1992,69(1):153-164
In a retrospective multicenter study to investigate the correlation between estrogen (ER) and/or progesterone receptors (PgR) in primary breast cancer with patient prognosis, 3118 patients with operable breast cancer (International Union Against Cancer Stages I, II, and III) were investigated from ten hospitals in Japan who underwent surgery from October 1972 to December 1982; 3089 were evaluable. The ER-positive and PgR-positive cancers were found in 56% and 34% of patients, respectively. The positivities decreased as the tumor size increased but were independent on lymph node metastasis. There were no significant differences in relapse-free survival (RFS) in relation to receptor status (median follow-up, 89 months [ER], 84 months [PgR]). However, in patients with four or more positive nodes, those with PgR-positive cancer had a longer RFS. The patients with ER-positive cancer survived significantly longer than ER-negative ones, with the greatest difference seen in those with four or more positive nodes. There was a significantly longer postrelapse survival (PRS) for patients with ER-positive cancer because of the different distribution of the major metastasis and better responses to first-line and subsequent treatments. Cox's multivariate analysis showed that overall survival but not PRS was affected by ER (and more weakly by PgR) because of the longer PRS in patients with ER-positive cancer. 相似文献
89.
Ken Kodama Osamu Doi Masahiko Higashiyama Hideoki Yokouchi Keiko Kuriyama 《Surgery today》1997,27(12):1123-1130
Between 1969 and 1995, 180 patients underwent complete resection of lung metastases during initial thoracotomy at our institute,
involving the resection of 917 pulmonary nodules at 202 thoracotomy procedures. The overall postmetastasectomy 5- and 10-year
survival rates were 46% and 30%, respectively. Of 111 patients who underwent segmentectomy and/or local excision, 57 had multiple
metastases, 39 of whom were treated by Nd:YAG laser after 1986, and 18 by conventional procedures before 1985. The average
number of tumors resected per patient treated with the Nd:YAG laser was significantly greater than that of those treated with
conventional procedures. However, the survival curve of the laser-treated group was better than that of the laser-nontreated
group. Moreover, slightly better survival was achieved in patients operated on after 1992 compared with those operated on
before 1991. We conclude that the laser technique may be warranted to afford complete resection of metastases and adequate
pulmonary reservation in combination with a selected approach for thoracotomy under the exact detection of tumor localization
using the most recent high-quality computed tomography (CT) scan. Furthermore, a one-stage operation to control synchronous
intra- and extrapulmonary malignamcies may become a possible option in combination with selective adjunctive therapy. 相似文献
90.
STUDY OBJECTIVE--The aim was to clarify the inhibitory effect of the selective kappa agonist, spiradoline, on coronary arterial smooth muscle in relation to the intracellular Ca2+ concentration. DESIGN--The inhibitory effect of spiradoline was investigated (1) on the contractile response of pig coronary artery to the readmission of Ca2+, following initial exposure to Ca2+ free medium and depolarisation with 40 mM K+; (2) on the intracellular Ca2+ concentration as assessed using the fluorescent calcium indicator fura-2. Relaxant responses to spiradoline in isolated porcine coronary artery strips contracted with K+ and prostaglandin F2 alpha were also examined. EXPERIMENTAL MATERIAL--Coronary arteries isolated from pigs of both sexes were used. The right and left circumflex coronary arteries were cut into 3 mm wide strips which were used to measure the change in contractile force and the intracellular Ca2+ concentration. MEASUREMENTS AND MAIN RESULTS--Prior treatment with spiradoline at 2 x 10(-6) mol.litre-1 or more inhibited the contractile response to the readmission of Ca2+ in porcine coronary artery exposed to Ca2+ free medium in the presence of high K+. Naloxone at 3 x 10(-4) mol.litre-1 did not reverse the inhibitory action of 2 x 10(-5) M spiradoline. Ca2+ induced contraction was inhibited completely by 10(-4) M spiradoline. Moreover, spiradoline caused relaxation in arterial preparations that had been contracted with K+ (15 to 25 mmol.litre-1) or prostaglandin F2 alpha (10(-6) to 3 x 10(-6) mol litre-1), greater relaxation being seen in the K+ induced contraction. The intracellular Ca2+ concentration was significantly lowered by 2 x 10(-5) M spiradoline. CONCLUSIONS--The relaxant response of coronary artery to spiradoline is, in part, attributable to interference with Ca2+ entry into the arterial smooth muscle. 相似文献