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961.
Tokoro T Orti LS Ookochi O Taniguchi K Hirai T Yamashita K Inoue S Takeda S Kaneko T Nakao A 《Surgery today》2003,33(2):138-141
We report the rare case of an intraductal papillary mucinous tumor (IPMT) in a man younger than 30 years of age. The patient
was admitted with upper abdominal pain and an elevated amylase level of 662 IU/l. Ultrasonography showed a cystic mass in
the pancreatic body and endoscopic retrograde cholangiopancreatography (ERCP) revealed a dilated pancreatic duct with a filling
defect communicating with the tumor. He was successfully treated by segmental resection, which seems to be the best surgical
option for pancreatic body tumors since it results in long-term survival and preserves as much pancreatic parenchyma as possible.
Nevertheless, it can only be done in the absence of additional nodules along the pancreatic duct. A pathological diagnosis
of intraductal papillary adenocarcinoma of the noninvasive type was confirmed, and both stumps were free of tumor.
Received: August 8, 2001 / Accepted: July 2, 2002
Reprint requests to: T. Tokoro 相似文献
962.
Amelioration of diabetic nephropathy in SPARC-null mice 总被引:5,自引:0,他引:5
Taneda S Pippin JW Sage EH Hudkins KL Takeuchi Y Couser WG Alpers CE 《Journal of the American Society of Nephrology : JASN》2003,14(4):968-980
SPARC (Secreted Protein, Acidic and Rich in Cysteine) is a matricellular protein that inhibits mesangial cell proliferation and also affects production of extracellular matrix (ECM) by regulating transforming growth factor-beta1 (TGF-beta1) and type I collagen in mesangial cells. This study is an investigation of the role of SPARC in streptozotocin (STZ)-induced diabetic nephropathy (DN) of 6-mo duration in wild type (WT) and SPARC-null mice. SPARC expression was evaluated by immunohistochemistry (IHC) and by in situ hybridization (ISH). Deposition of type I and IV collagen and laminin was evaluated by IHC, and TGF-beta 1 mRNA was assessed by ISH. Renal function studies revealed no significant difference in BUN between diabetic SPARC-null mice and diabetic WT mice, whereas a significant increase in albumin excretion was detected in diabetic WT relative to diabetic SPARC-null mice. Diabetic WT animals exhibited increased levels of SPARC mRNA and protein in glomerular epithelial cells and in interstitial cells, in comparison with nondiabetic WT mice. Neither SPARC mRNA nor protein was detected in SPARC-null mice. Morphometry revealed a significant increase in the percentage of the glomerular tufts occupied by ECM in diabetic WT compared with nondiabetic WT mice, although there was no difference in the mean glomerular tuft area among groups. In contrast, diabetic SPARC-null mice did not show a significant difference in the percentage of the glomerular tufts occupied by ECM relative to nondiabetic null mice. Tubulointerstitial fibrosis was ameliorated in diabetic SPARC-null mice compared with diabetic WT animals. Further characterization of diabetic SPARC-null mice revealed diminished glomerular deposition of type IV collagen and laminin, and diminished interstitial deposition of type I and type IV collagen correlated with decreases in TGF-beta 1 mRNA compared with WT diabetic mice. These observations suggest that SPARC contributes to glomerulosclerosis and tubulointerstitial damage in response to hyperglycemia through increasing TGF-beta 1 expression in this model of chronic DN. 相似文献
963.
Aoyama S Shirakawa O Ono H Hashimoto T Kajimoto Y Maeda K 《Psychiatry and clinical neurosciences》2003,57(5):545-547
Glutamate dysfunction has been hypothesized to be involved in the pathophysiology of schizophrenia. The human homolog of Drosophila discs large protein (hDLG) and post-synaptic density-95-associated protein-1 (DAP-1) is one of the major proteins that are involved in intracellular signal transduction via N-methyl-d-aspartate receptors. In the present study 33 Japanese patients with schizophrenia were screened for mutations in the DAP-1 gene. A single nucleotide polymorphism was identified in the DAP-1 gene (1618A/G). A case-control study using a larger sample of unrelated patients and controls did not reveal a significant association between this polymorphism and schizophrenia. The results do not provide evidence that the DAP-1 gene is involved in vulnerability to schizophrenia. 相似文献
964.
Suzuki S Nogawa S Tanaka K Koto A Fukuuchi Y Kuwana M 《Clinical neurology and neurosurgery》2003,106(1):16-18
Pure red cell aplasia (PRCA) is well known to be concomitant with myasthenia gravis (MG), but it is difficult to predict the development of PRCA in patients with MG. Of 135 patients with MG, four (2.9%) had PRCA. All patients developed PRCA after thymectomy during a period when MG was in remission. The frequencies of thymoma, bulbar involvement and high anti-acetylcholine receptor (AChR) antibody levels were significantly higher in four patients with PRCA. Japanese MG patients with these characteristics at presentation were at significant risk for the development of PRCA after thymectomy. 相似文献
965.
966.
Miyashita M Suzuki-Inatomi T Hirai N 《Journal of vestibular research : equilibrium & orientation》2003,13(2-3):57-64
The effect of postural changes on respiration was investigated in ten anesthetized cats by applying body tilting during the inspiration phase while recording respiratory patterns, as given by the diaphragmatic EMG, together with either the lung volume or the air flow temperature. The results show that the head-up tilting during inspiration reduced the period of the inspiratory phase and increased the end-inspiratory lung volume. On the other hand, the head-down tilting during inspiration had opposite effects. These effects disappeared after transection of the vagus nerve. However, labyrinthectomy did not diminish the effects, probably because of functional suppression of the vestibular system due to the anesthetic. When correlating the activity of 15 vagal afferents presumably originating from the slowly adapting lung stretch receptors with lung volume changes during tilting, their maximum firing rate (87 +/- 15.7 Hz) was increased with an increase in the lung inflation volume and was attained earlier on head-up tilting and it was reduced with a decrease of the lung volume on head-down tilting (63 +/- 16.6 Hz) as compared with the value in the horizontal position (74 +/- 14.2 Hz). These results suggest that respiratory modulation during head-up or head-down tilting is consistent with the Hering-Breuer reflexes and minimizes the externally induced lung volume changes during postural changes. 相似文献
967.
To assess the exposure of welders to thorium-232 (232Th) during tungsten inert gas arc (TIG) welding, airborne concentrations of 232Th in the breathing zone of the welder and background levels were measured. The radioactive concentrations were 1.11 x 10(-2) Bq/m3 during TIG welding of aluminum (TIG/Al), 1.78 x 10(-4) Bq/m3 during TIG welding of stainless steel (TIG/SS), and 1.93 x 10(-1) Bq/m3 during electrode sharpening, with 5.82 x 10(-5) Bq/m3 background concentration. Although the annual intake of 232Th estimated using these values did not exceed the annual limit intake (ALI, 1.6 x 10(2) Bq), we recommend reducing 232Th exposure by substituting thoriated electrodes with a thorium-free electrodes, setting up local ventilation systems, and by using respiratory protective equipment. It is also necessary to inform workers that thoriated tungsten electrodes contain radioactive material. 相似文献
968.
Hirai K Ozeki Y Nakano T Takezoe R Nakanishi M Asano Y Higuchi H 《Environmental health and preventive medicine》2001,5(4):138-143
The effects of a 47-week diet of butter or safflower oil as fat in combination with casein or soy protein as protein were
observed for the serum concentrations of lipids and fatty acid compositions in rat serum and heart. Serum total cholesterol
(Chol) did not differ among the four experimental diet groups. In the butter groups, significantly higher low-density lipoprotein
(LDL)-Chol and lower high-density lipoprotein (HDL)-Chol were observed than in the safflower oil groups (p<0.005, respectively).
Higher levels of α-tocopherol were found in the butter groups than in the safflower oil groups (p<0.05) and in the casein
groups than in the soy protein groups (p<0.01). In comparison with the safflower oil groups, the butter groups showed higher
n-3 polyunsaturated fatty acids (PUFA) contents and lower n-6 PUFA contents in serum and the hearts (p<0.005). The ratios
of n-3/n-6 PUFA in the butter groups in serum, 0.26 and 0.18, and in the hearts, 0.37 and 0.36, (butter-casein diet and butter-soy
protein diet, respectively) were higher than those of the safflower oil groups of under 0.01 in serum and 0.02 and 0.03 in
the hearts (safflower oil-casein diet and safflower oil-soy protein diet, respectively) (p<0.005). In the soy protein groups,
higher n-3 PUFA contents in the hearts were found than those of the casein groups (p<0.05). This study suggested that the
butter diet induces higher levels of n-3 PUFA and a higher n-3/n-6 PUFA ratio than the safflower oil diet in rat serum and
hearts over a long feeding period. 相似文献
969.
Hideo Torii Keizo Takahashi Fumiaki Yoshitomi Kazunori Miyata Yasuo Ishii Tetsuro Oshika 《Ophthalmology》2001,108(12):2182-2185
Objective
To investigate the incidence of spontaneous detachment of the anterior hyaloid membrane from the posterior lens capsule and to explore the possibility of surgical separation of the anterior hyaloid membrane.Design
Prospective nonrandomized interventional comparative trial and comparative human tissue study.Participants
Thirty-eight eyes of 32 patients undergoing primary pars plana vitrectomy combined with cataract extraction and intraocular lens implantation and 3 eye bank eyes for histopathologic examination.Methods
The anterior hyaloid membrane and posterior lens capsule were observed with a fiberoptic endoscope. Surgical separation of the anterior hyaloid membrane was attempted by either the hydrodissection method before cataract extraction (18 eyes) or the direct suction method after cataract extraction (20 eyes). In eye bank eyes, histopathologic examination was performed with (one eye) and without (two eyes) surgical separation of the anterior hyaloid membrane.Main outcome measures
Incidence of spontaneous detachment and success rate of surgical detachment of the anterior hyaloid membrane.Results
No eye displayed spontaneous detachment of the anterior hyaloid membrane. Using the hydrodissection method, complete detachment of the anterior hyaloid membrane was achieved in 10 eyes (55.6%), partial detachment was attained in 2 eyes (11.1%), and detachment was not induced at all in 6 eyes (33.3%). With the direct suction method, the anterior hyaloid membrane was completely separated from the posterior lens capsule in 10 eyes (50%), partially detached in 10 eyes (50%), and not detached at all in any eye. The direct suction method had a significantly higher success rate than the hydrodissection method (P < 0.001, chi-square test). In eye bank eyes, the surgical manipulation induced complete separation of the anterior hyaloid membrane from the lens capsule.Conclusions
Spontaneous detachment of the anterior hyaloid membrane from the posterior lens capsule is very rare. Under endoscopic observation, surgical detachment of the anterior hyaloid membrane was possible in half of the patients. 相似文献970.
Haraki T Takegoshi T Kitoh C Kajinami K Wakasugi T Hirai J Shimada T Kawashiri M Inazu A Koizumi J Mabuchi H 《Clinical nephrology》2001,56(2):132-139
BACKGROUND: Patients with end-stage renal disease (ESRD) have high mortality from atherosclerotic/atherothrombotic vascular disease (AVD). However, the role of an elevated plasma total homocysteine (tHcy) level as a risk factor is uncertain in ESRD. METHODS: We enrolled 55 ESRD patients in a prospective follow-up study in order to evaluate the prognostic significance of their tHcy levels, common methylenetetrahydrofolate reductase (MTHFR) gene polymorphism, and other atherosclerotic risk factors, in combination with the results of B mode ultrasound for carotid arteries. RESULTS: Mean intima-media thickness of the common carotid artery (CCA-IMT) in ESRD patients was thicker than that in 102 age- and sex-matched healthy controls. Carotid plaque was more frequently present in patients compared with controls, as was calcified plaque more common in patients (p < 0.001). Plasma tHcy levels (mean +/- SD) in patients (39.1 +/- 27.2 nmol/ml) were higher than that (8.8 +/- 2.7 nmol/ml) in controls (p < 0.001). Folic acid was the major determinant of elevated tHcy levels in ESRD patients. During the follow-up period of 31 +/- 3 months, 14 patients had one or more AVD complications, and 10 consequently died from AVD causes. Proportional hazards modeling showed that 5-year intervals of age (relative risk of 2.95, 95% CI 1.62 - 5.37), 10 nmol/ml intervals of tHcy levels (relative risk of 2.31, 95% CI 1.31 - 4.08), and presence of diabetes mellitus (relative risk of 6.62, 95% CI 1.07 +/- 40.8) were independent predictors of future AVD events, and tHcy levels (relative risk of 2.67, 95% CI 1.29 - 5.52) and age (relative risk of 2.10, 95% CI 1.15 - 3.83) were those of AVD mortality. We also found a significant association between carotid plaque prevalence and AVD events (X(2) = 11.6, p = 0.001). CONCLUSION: Hyperhomocysteinemia, diabetes mellitus, and carotid atherosclerosis appeared to contribute independently to increase the risk of AVD outcome in Japanese patients with ESRD. 相似文献