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31.
AIM To study the safety of insertion of metallic stents in elderly patients with unresectable distal malignant biliary obstruction.METHODS Of 272 patients with unresectable distal malignant biliary obstruction, 184 patients under the age of 80 were classified into Group A, and 88 subjects aged 80 years or more were classified into Group B. The safety of metallic stent insertion, metal stent patency period, and the obstruction rate were examined in each group.RESULTS In Group B, patients had a significantly worse per-formance status, high blood pressure, heart disease, cerebrovascular disease, and dementia; besides the rate of patients orally administered antiplatelet drugs or anticoagulants tended to be higher(P 0.05). Metallic stents were successfully inserted in all patients. The median patency period was 265.000 ± 26.779(1-965) d; 252.000 ± 35.998(1-618) d in Group A and 269.000 ± 47.885(1-965) d in Group B, with no significant difference between the two groups. Metallic stent obstruction occurred in 82 of the 272(30.15%) patients; in 53/184(28.80%) patients in Group A and in 29/88(32.95%) of those in Group B, showing no significant difference between the two groups. Procedural accidents due to metal stent insertion occurred in 24/272(8.8%) patients; in 17/184(9.2%) of patients in Group A and in 7/88(8.0%) of those in Group B, with no significant difference between the two groups, either.CONCLUSION These results suggested that metallic stents can be safely inserted to treat unresectable distal malignant biliary obstruction even in elderly patients aged 80 years or more.  相似文献   
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Background

IgG4-related disease (IgG4-RD) is a novel clinical disease entity characterized by elevated serum IgG4 concentration and tumefaction or tissue infiltration by IgG4+ plasma cells. Although IgG4-RD is not rare and is clinically important, its clinical diagnostic criteria have not been established. Comprehensive diagnostic criteria for IgG4-RD, including the involvement of various organs, are intended for the practical use of general physicians and nonspecialists.

Methods

Two IgG4-RD study groups, the Umehara and Okazaki teams, were organized by the Ministry of Health, Labor and Welfare Japan. As IgG4-RD comprises a wide variety of diseases, these groups consist of physicians and researchers in various disciplines, including rheumatology, hematology, gastroenterology, nephrology, pulmonology, ophthalmology, odontology, pathology, statistics, and basic and molecular immunology throughout Japan, with 66 and 56 members of the Umehara and Okazaki teams, respectively. Collaborations of the two study groups involved detailed analyses of clinical symptoms, laboratory results, and biopsy specimens of patients with IgG4-RD, resulting in the establishment of comprehensive diagnostic criteria for IgG4-RD.

Results

Although many patients with IgG4-RD have lesions in several organs, either synchronously or metachronously, and the pathological features of each organ differ, consensus has been reached on two diagnostic criteria for IgG4RD: (1) serum IgG4 concentration >135?mg/dl, and (2) >40% of IgG+ plasma cells being IgG4+ and >10?cells/high powered field of biopsy sample. Although the comprehensive diagnostic criteria are not sufficiently sensitive for the diagnosis of type 1 IgG4-related autoimmune pancreatitis (IgG4-related AIP), they are adequately sensitive for IgG4-related Mikulicz??s disease (MD) and kidney disease (KD). In addition, the comprehensive diagnostic criteria, combined with organ-specific diagnostic criteria, have increased the sensitivity of diagnosis to 100% for IgG4-related MD, KD, and AIP.

Conclusion

Our comprehensive diagnostic criteria for IgG4-RD are practically useful for general physicians and nonspecialists.  相似文献   
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Kamisawa T 《Radiology》2005,236(1):371; author reply 371-371; author reply 372
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36.
We present a case of a primary advanced gastric tumor that was composed of 2 different pathological components: small cell carcinoma and moderately-differentiated adenocarcinoma. The patient was still alive four years after the surgery was performed, without recurrence. A large part of the tumor consisted of a diffuse sheet of small cell carcinoma, which transitioned into another small portion consisting of moderately-differentiated tubular adenocarcinoma components. Therefore, this case raised the possibility that small cell gastric carcinoma may originate from totipotential stem cells of the stomach. Although small cell carcinoma progresses aggressively, and patients with it have an extremely poor prognosis, this patient recovered uneventfully after the surgical resection, and has remained in good health, without any recurrences.  相似文献   
37.
Nontransportable blockers of the glutamate transporters are important tools for investigating mechanisms of synaptic transmission. DL-threo-beta-Benzyloxyaspartate (DL-TBOA) is a potent blocker of all subtypes of the excitatory amino acid transporters (EAATs). We characterized novel L-TBOA analogs possessing a substituent on their respective benzene rings. The analogs significantly inhibited labeled glutamate uptake, the most potent of which was (2S,3S)-3-[3-[4-(trifluoromethyl)benzoylamino]benzyloxy]aspartate (TFB-TBOA). In an uptake assay using cells transiently expressing EAATs, the IC(50) values of TFB-TBOA for EAAT1, EAAT2, and EAAT3 were 22, 17, and 300 nM, respectively. TFB-TBOA was significantly more potent at inhibiting EAAT1 and EAAT2 compared with L-TBOA (IC(50) values for EAAT1-3 were 33, 6.2, and 15 microM, respectively). Electrophysiological analyses revealed that TBOA analogs block the transport-associated currents in all five EAAT subtypes and also block leak currents in EAAT5. The rank order of the analogs for potencies at inhibiting substrate-induced currents was identical to that observed in the uptake assay. However, the kinetics of TFBTBOA differed from the kinetics of L-TBOA, probably because of the strong binding affinity. Notably, TFB-TBOA did not affect other representative neurotransmitter transporters or receptors, including ionotropic and metabotropic glutamate receptors, indicating that it is highly selective for EAATs. Moreover, intracerebroventricular administration of the TBOA analogs induced severe convulsive behaviors in mice, probably because of the accumulation of glutamate. Taken together, these findings indicate that novel TBOA analogs, especially TFB-TBOA, should serve as useful tools for elucidating the physiological roles of the glutamate transporters.  相似文献   
38.
Abstract Whether advanced pancreatic carcinomas should be surgically removed has been a basic issue because performing an extended resection is futile if it has only a minimum impact on survival. The purpose of this study was to compare the results of pancreatic resection with those of a bypass operation for patients with stage III or IVA pancreatic carcinomas while applying intraoperative radiation therapy (IORT). The therapeutic outcomes of 132 patients who had received IORT for stage III or IVA carcinoma were analyzed retrospectively. The patients were divided into two groups: Group 1 included 68 patients with locally unresectable tumors who underwent a bypass operation; group 2 included 64 patients with resectable tumors who underwent pancreatic resection. Postoperative external beam radiation therapy (EBRT) was also delivered to 90 patients. Multivariate analysis indicated that strong independent predictors of increased survival were EBRT for group 1 (p < 0.0001) and R0 resection for group 2 (p = 0.017). Twenty patients who had been subjected to R0 resection showed the best survival, with a 3-year survival rate of 45%. The survival of group 1 patients receiving EBRT (n = 47) nearly equaled that of group 2 patients undergoing R1 or R2 resection (n = 44) (p = 0.72); but group 1 patients with tumors ≤ 6 cm (n = 31) had a better survival rate than group 2 patients with tumors > 3 cm (n = 28) (p = 0.03). We concluded that postoperative EBRT is essential for improving the survival outcome, even after administering IORT. Patients with stage III lesions undergoing an R0 resection and receiving IORT demonstrated an excellent 3-year survival. A bypass operation plus IORT in combination with EBRT is preferred over IORT used as an adjuvant to R1 or R2 resection. Electronic Publication  相似文献   
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Effects of a spider toxin (JSTX) on hippocampal CA1 neurons in vitro   总被引:3,自引:0,他引:3  
The effect of a toxin (JSTX) obtained from Nephila clavata (Joro spider) on the CA1 pyramidal neurons of the hippocampus was studied using slice preparations. JSTX blocked the excitatory postsynaptic potentials (EPSPs) in the pyramidal neuron evoked by Schaffer collateral stimulation but was without effect on the antidromic action potentials or on the resting conductance. Depolarization induced by ionophoretic application of glutamate was readily suppressed by JSTX but aspartate-induced depolarization was much less sensitive to the toxin. Among preferential agonists activating 3 receptor subtypes for excitatory amino acids, quisqualate responses were most effectively suppressed by JSTX. Kainate responses were similarly suppressed but in some cells higher concentration of the toxin was needed to block the responses. N-methyl-D-aspartate (NMDA) responses were the least sensitive to JSTX but they were suppressed by +/- 2-amino-5-phosphonovaleric acid (APV). Long term potentiation (LTP) once it had taken place was not completely inhibited by APV. In the presence of JSTX, however, LTP was blocked and tetanic stimuli produced only a short-lived potentiation. In Mg2+ free solution, an orthodromic stimulation evoked repetitive spike responses which were superimposed on the depolarization following the initial spike. APV suppressed the depolarization and associated spikes leaving an orthodromic response which was sensitive to JSTX. The results suggest that JSTX blocks EPSPs in CA1 pyramidal neurons which are mediated by non-NMDA type receptors.  相似文献   
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