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91.
Masami Shibukawa Masaru Yanagisawa Ryota Morinaga Tomomi Shimasaki Shingo Saito Shao-ting Wang Yu-qi Feng 《RSC advances》2018,8(47):26849
The effects of temperature and background counterions on ion-exchange selectivity for alkali metal ions and tetraalkylammonium ions on strongly acidic cation-exchange resins have been investigated using superheated water ion-exchange chromatography (SW-IEC). We have found out that alkali metal ions show reversal in the order of the distribution coefficient (KD), from Li+ < Na+ < K+ < Rb+ in water at ordinary temperature to Rb+ < K+ < Na+ < Li+ in superheated water, when a relatively large cation such as cesium ion is used as the background counterion. The effect of counterion on the ion-exchange selectivity is enhanced with the ion-exchange resins of higher ion-exchange capacity and cross-linking degree. Tetraalkylammonium ions chosen as model ions for poorly hydrated ions also exhibit reversal in the order of KD at around 430 K in superheated water. However, the effect of the nature of alkali metal counterions on the change in KD values of tetraalkylammonium ions is rather small compared with the effect on the KD of alkali metal ions. These results are attributed to the change in local hydration structures of the ions in the ion-exchange resin due to dehydration of alkali metal ions enhanced by interionic contacts of the analyte ion with the coexisting counterion and lower hydration energy of the ions at elevated temperatures. Although it has been considered that temperature is not effective at changing the ion-exchange separation selectivity, significant selectivity changes can be achieved by SW-IEC.Metal ions in cation-exchange resins are dehydrated by interionic contacts with a co-existing counterion at elevated temperatures, which causes a drastic change in separation selectivity. 相似文献
92.
Yasuharu Matsunaga-Lee MD Yasuyuki Egami MD Kohei Ukita MD Akito Kawamura MD Hitoshi Nakamura MD Yutaka Matsuhiro MD Koji Yasumoto MD Masaki Tsuda MD Akihiro Tanaka MD Naotaka Okamoto MD Masamichi Yano MD PhD Ryu Shutta MD Yasushi Sakata MD PhD FACC FESC Masami Nishino MD PhD FACC FESC Jun Tanouchi MD PhD 《Journal of cardiovascular electrophysiology》2021,32(1):58-66
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95.
Vipoma of the Pancreas Complicating Ulcerative Colitis 总被引:2,自引:0,他引:2
Hidenori Yanagi M.D. Masato Kusunoki M.D. Youichirou Sakanoue M.D. Yasutsugu Shoji M.D. Takehira Yamamura M.D. Masami Murai M.D. Nobuteru Kikkawa M.D. Joji Utsunomiya M.D. 《The American journal of gastroenterology》1991,86(8):1066-1069
We report a case of vipoma of the pancreas in conjunction with ulcerative colitis in a 20-yr-old woman. Twenty months after the onset of ulcerative colitis, the patient complained of watery diarrhea and was found to have an electrolyte disorder. A pancreatic tumor was detected by ultrasonography and computed tomography, along with an elevation of serum vasoactive intestinal polypeptide (VIP). The secretory diarrhea diminished dramatically, and the serum VIP level decreased into the normal range immediately after resection of the pancreatic tumor. Immunohistochemical staining revealed a pancreatic vipoma. Despite removal of the vipoma, she underwent restorative proctocolectomy and ileal J-pouch anal anastomosis 2 yr later due to progression of the ulcerative colitis. Postoperative course was uneventful, with excellent functional results. Knowledge of this rare condition accompanying ulcerative colitis may help in the management of the patient with an atypical clinical course. 相似文献
96.
Shuya Kusumoto Itsuro Jinnai Katsuro Itoh Nobutaka Kawai Tohru Sakata Akira Matsuda Kazunori Tominaga IKUO Murohashi Masami Bessho Kunitake Harashima & Atsuko Heshiki 《British journal of haematology》1996,99(3):649-655
Sixty-one consecutive patients with multiple myeloma were studied with magnetic resonance (MR) imaging of the spine. Sagittal T1-weighted and short inversion time (TI) inversion recovery (STIR) images were obtained. The MR patterns of the bone marrow were classified as diffuse (D) ( n = 26), nodular (N) ( n = 11), D + N ( n = 13) or normal (n) ( n = 11). Abnormal patterns were seen in 50 (82%) of the 61 patients. Correlations were found between the MR imaging patterns and some laboratory findings (WBC, haematocrit, platelet count, serum albumin, and percentage of marrow plasmacytosis). The survival of the patients with abnormal MRI patterns was significantly poorer than that of the patients with normal patterns. However, the survival of patients with a nodular pattern did not differ from those with a normal pattern. The MR imaging pattern of the bone marrow in patients with multiple myeloma is a useful factor in the assessment of prognosis. 相似文献
97.
Masami Taniguchi Naomi Tsurikisawa Noritaka Higashi Hiroshi Saito Haruhisa Mita Akio Mori Hiroki Sakakibara Kazuo Akiyama 《Allergology international》2007,56(2):97-103
Churg-Strauss syndrome (CSS) is characterized by the presence of asthma, eosinophilia, and small-vessel vasculitis with granuloma. It is a distinct entity, as determined from all classifications of systemic vasculitis. The poor prognostic factors in CSS are renal insufficiency, cardiomyopathy, severe gastrointestinal (GI) tract, and central nervous systems (CNS) involvement. The initial management of CSS should include a high dose of a corticosteroid: prednisone at 1 mg/kg/day or its equivalent for methylprednisolone with tapering over 6 months. In patients with severe or rapidly progressing CSS, the administration of methylprednisolone pulse at 1 g/body/day for 3 days is recommended. When corticosteroid therapy does not induce remission, or when patients have poor prognostic factors, immunosuppressive cytotoxic therapy is indicated. However, some patients with severe CSS often show resistance to conventional treatment. We think that IVIG therapy is a hopeful candidate for second-line treatment for CSS patients, particularly in the case of neuropathy and/or cardiomyopathy, which are resistant to conventional therapy. However, there is not much evidence supporting the effectiveness of IVIG in CSS, and the mechanisms underlying the action of IVIG remain unclear. Now we are performing clinical trials of IVIG therapy for CSS patients who are resistant to conventional treatment, through a nationwide double-blinded placebo-controlled study in Japan. 相似文献
98.
Takatsugu Yamamoto Mizue Tamura Toshikazu Hamauzu Akiko Nakayama Kazuo Kawasugi Masahide Kamakura Tadatoshi Kinoshita Yasushi Kuyama Masami Yamanaka Li-man Wang Masaki Sanaka Satoru Mineshita 《Journal of gastroenterology》1997,32(2):241-245
A 45-year-old man with intestinal Behçet's disease noticed an enlarged right cervical lymph node, and was diagnosed with diffuse large cell type, non-Hodgkin's lymphoma. The intrapelvic lymph tract was markedly deformed because of recurrent ileocecal ulceration, and conventional lymphoscintigraphy with a common tracer did not abolish the suspicion that lymphoma cells may have invaded the lymph nodes. Dynamic lymphoscintigraphy with a new tracer,99mtechnetium-diethylene triamine pentaacetic acid-human serum albumin, because of its high detection sensitivity, was very useful for excluding this suspicion, and for determining the clinical stage of lymphoma. Combination induction chemotherapy led to complete remission without any adverse effects, but subsequent supportive therapy with same protocol could not be completed because of progression of the intestinal lesions. Special management for the intestinal lesions, such as bowel rest, may be essential with chemotherapy for patients with intestinal Behçet's disease. 相似文献
99.
Hepatic resection under in situ hypothermic hepatic perfusion 总被引:2,自引:0,他引:2
Kaiho T Tanaka T Tsuchiya S Yanagisawa S Takeuchi O Miura M Saigusa N Kitakata Y Miyazaki M 《Hepato-gastroenterology》2003,50(51):761-765
BACKGROUND/AIMS: Temporary inflow occlusion of the portal triad has been used frequently in hepatectomy to minimize bleeding. On the other hand, Pringle's maneuver produces ischemic-reperfusion injury especially in patients with underlying liver disease. METHODOLOGY: Thirty-seven cases of hepatic resections were performed with intermittent Pringle's maneuver (IP group; n = 17) and in situ hypothermic perfusion (CP group; n = 20). In the CP group, hepatic inflow was continuously occluded, and 4-degree Centigrade Ringer's lactate was administered by drip during resection. Hepatic outflow occlusion was not performed. RESULTS: All patients tolerated the procedures well. Cold perfusion technique significantly decreased both the times required and the blood loss in hepatectomy (p < 0.05). Serum hyaluronic acid levels gradually increased after the induction of hepatectomy and peaked 10 minutes after reperfusion in the both groups. Thereafter, it decreased and showed a significantly lower level in the CP group until 60 minutes after reperfusion (p < 0.05). Hepaplastin levels remained significantly higher in the CP group one week after operation (p < 0.05). CONCLUSIONS: Using the technique of in situ hypothermic perfusion, we can prolong the ischemic time safely with minimal systemic influence even in cases with underlying liver diseases. This may compare favorably with intermittent Pringle's maneuver in terms of reducing hepatic sinusoidal endothelial cell damage during hepatectomy and reperfusion. 相似文献
100.
Noriko Inoue Toshiyuki Ishikawa Shinichi Sumita Takeshi Nakagawa Tsukasa Kobayashi Kohei Matsushita Katsumi Matsumoto Yasuo Ohkusu Minoru Taima Masami Kosuge Kazuaki Uchino Kazuo Kimura Satoshi Umemura 《Circulation journal》2005,69(2):201-204
BACKGROUND: Atrioventricular (AV) delay optimization may be important in patients with biventricular pacing and the optimal AV delay can be predicted using Doppler echocardiography and the formula: optimal AV delay = AV delay-the interval between the end of A wave and complete closure of the mitral valve when the AV delay is set at slightly prolonged AV delay. METHODS AND RESULTS: In the present study the efficacy of this method was evaluated in 5 patients (67.4+/-8.0 (SD) years old) with biventricular pacing. Cardiac output (CO) and diastolic filling time were measured by Doppler echocardiography. When the AV delay was set at the predicted optimal AV delay -25 ms, the predicted optimal AV delay (133+/-66 ms) and predicted optimal AV delay + 25 ms, the respective CO were 4.5+/-0.9, 5.3+/-1.0, 4.8+/-1.0 L/min (p<0.05, ANOVA) and the diastolic filling times were 364 +/-100, 373+/-105, 335+/-84 ms (p<0.05, ANOVA). Congestive heart failure improved from New York Heart Association class 3.6+/-0.5 to 1.4+/-0.5 (p<0.001). CONCLUSIONS: AV delay optimization is important in patients with biventricular pacing and can be easily achieved by the new method. 相似文献