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91.
92.
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
93.
Shingo Nasu Kunimitsu Kawahara Yuki Han Norio Okamoto Yoshitaka Tamura Hidekazu Suzuki Takayuki Shiroyama Yumiko Samejima Tomohiro Kanai Yoshimi Noda Ayako Tanaka Naoko Morishita Kayo Ueda Shoji Hashimoto Tomonori Hirashima Takayuki Nagai 《Internal medicine (Tokyo, Japan)》2021,60(3):445
Miliary tuberculosis is a potentially lethal type of tuberculosis that results from the hematogenous dissemination of Mycobacterium tuberculosis bacilli. We herein describe the case of a 34-year-old man that presented with a one-month history of cough and fever, while his sputum smear results were negative. Chest computed tomography revealed bilateral centrilobular ground-glass opacification (GGO), suggestive of hypersensitivity pneumonitis; thus, bronchoscopy was performed. Cryobiopsy specimens revealed necrotic granulomas. A re-examination of sputum after bronchoscopy identified Mycobacterium tuberculosis, and miliary tuberculosis was diagnosed. A cryobiopsy might be useful for diagnosing miliary tuberculosis pathologically, particularly when miliary nodules may be masked by GGO. 相似文献
94.
Atsuko Furukawa Yukio Abe Atsushi Morizane Tsuyoshi Miyaji Shingo Hosogi Hiroshi Ito 《Journal of cardiology》2021,77(6):613-619
BackgroundNo established methodology exists for diagnosis of aortic stenosis (AS) using focused cardiac ultrasound (FOCUS). We evaluated the diagnostic accuracy of our developed visual AS score for screening AS in an emergency department.MethodsSeventy-two emergency outpatients with suspected cardiovascular disease were studied. Emergency physicians assessed the visual AS score in addition to conducting the standard FOCUS, and then the aortic valve area index (AVAI) was measured by expert sonographers in the echocardiography laboratory. AVAI values >0.85 cm2/m2, 0.6–0.85 cm2/m2, and <0.6 cm2/m2 were defined as no or mild AS, moderate AS, and severe AS, respectively.ResultsSeventeen (24%) patients had moderate or severe AS. Visual AS scores assessed by emergency physicians and by expert sonographers showed excellent agreement (κ = 0.93), and a strong association was noted between the visual AS score assessed by emergency physicians and the AVAI assessed by expert sonographers (R = –0.71, p < 0.0001). A visual AS score ≥3 assessed by emergency physicians had a sensitivity of 82%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 95% for diagnosing moderate or severe AS. The prevalence of new-onset AS-related events during hospitalization was higher in patients with visual AS score ≥3 assessed by emergency physicians than in the remaining patients [7 (50%) vs. 2 (3%), p < 0.0001].ConclusionThe visual AS score is a useful AS screening tool for emergency physicians who are not expert cardiologists. 相似文献
95.
Shinzaki Shinichiro Matsuoka Katsuyoshi Tanaka Hiroki Takeshima Fuminao Kato Shingo Torisu Takehiro Ohta Yuki Watanabe Kenji Nakamura Shiro Yoshimura Naoki Kobayashi Taku Shiotani Akiko Hirai Fumihito Hiraoka Sakiko Watanabe Mamoru Matsuura Minoru Nishimoto Shohei Mizuno Shinta Iijima Hideki Takehara Tetsuo Naka Tetsuji Kanai Takanori Matsumoto Takayuki 《Journal of gastroenterology》2021,56(6):560-569
Journal of Gastroenterology - This multicenter prospective study (UMIN000019958) aimed to evaluate the usefulness of serum leucin-rich alpha-2 glycoprotein (LRG) levels in monitoring disease... 相似文献
96.
Shingo Tsujinaka Hideyuki Suzuki Tomoya Miura Yoshihiro Sato Chikashi Shibata 《World journal of gastroenterology : WJG》2022,28(47):6732-6742
This review aimed to highlight the etiology, diagnosis, treatment, and prevention of obstructive and secretory complications associated with diverting ileostomy (DI). Obstructive complications at the stoma site are termed stoma outlet obstruction (SOO) or stoma-related obstruction (SRO). The incidence of SOO/SRO is 5.4%-27.3%, and the risk factors are multifactorial; however, the configuration of the stoma limb and the thickness of the rectus abdominis muscle (RAM) may be of particular concern. Trans-stomal tube decompression is initially attempted with a success rate of 33%-86%. A thick RAM may carry the risk of recurrence. Surgical refinement, including a wider incision of the anterior sheath and adequate stoma limb length, avoids tension and immobility and may decrease SOO/SRO. Secretory complications of DI are termed high output stoma (HOS). Persistent HOS lead to water and sodium depletion, and secondary hyperaldosteronism, resulting in electrolyte imbalances, such as hypomagnesemia. The incidence of HOS is 14%-24%, with an output of 1000-2000 mL/d lasting up to three days. Treatment of HOS is commenced after excluding postoperative complications or enteritis and includes fluid intake restriction, antimotility and antisecretory drug therapies, and magnesium supplementation. Intensive monitoring and surveillance programs have been successful in decreasing readmissions for dehydration. 相似文献
97.
Kohki Nakamura MD PhD Takehito Sasaki MD Yutaka Take MD PhD Kentaro Minami MD Mitsuho Inoue MD Chisa Asahina MD Wataru Sasaki MD Shohei Kishi MD Shingo Yoshimura MD Yoshinori Okazaki MD Hiroyuki Motoda MD PhD Katsura Niijima MD PhD Yuko Miki MD PhD Koji Goto MD PhD Kenichi Kaseno MD PhD Eiji Yamashita MD PhD Keiko Koyama MD PhD Nobusada Funabashi MD PhD Shigeto Naito MD PhD 《Journal of cardiovascular electrophysiology》2021,32(1):16-26
98.
99.
Nagai M Horikoshi K Izumi T Seki S Taniguchi M Taniguchi I Mochizuki S 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》2004,18(5):353-362
We investigated the effects of an angiotensin-converting enzyme inhibitor and an angiotensin II type 1 receptor blocker on
cardiac hypertrophy in rats with renovascular hypertension. Renovascular hypertensive (Goldblatt) rats were surgically prepared
from Wistar rats. Four weeks later, the rats showed a significant increase in blood pressure. At high doses, both the perindopril
(1 mg/kg/day) and the candesartan (2 mg/kg/day) decreased the systolic pressure in these rats to the level of control Wistar
rats. At low doses (perindopril 0.1 mg/kg/day and candesartan 0.1 mg/kg/day), these drugs lowered blood pressure to 85% of
that in hypertensive rats.
Echocardiographic and morphological studies revealed severe cardiac hypertrophy and fibrosis in untreated Goldblatt rats.
High-dose treatment with both drugs suppressed the progression of hypertrophy and fibrosis. Also, low-dose perindopril prevented
cardiac hypertrophy and fibrosis. In contrast, at the same levels of blood-pressure reduction, low-dose candesartan did not
prevent cardiac fibrosis nor the upregulation of cardiac collagen types I and III mRNA observed in untreated Goldblatt rats.
Atrial natriuretic peptide mRNA was up-regulated in untreated Goldblatt rats. These changes were significantly decreased by
both doses of perindopril or the high dose of candesartan. Serum levels of angiotensin II and aldosterone were significantly
higher in untreated Goldblatt rats. Both doses of perindopril inhibited activation of the renin-angiotensin system, whereas
candesartan had weaker effects. In particular, serum aldosterone was 347 ± 20 pg/ml in low-dose perindopril versus 1796 ±
324 pg/ml in low-dose candesartan. These results suggest that there were no differences between the cardioprotective actions
of perindopril and candesartan at high dosages. On the other hand, low-dose treatment with perindopril was more effective
in preventing cardiac fibrosis than was low-dose treatment with candesartan, despite similar changes in blood pressure. It
is possible that changes in aldosterone secretion are related to this difference. 相似文献
100.
Konno S Murata M Toda T Yoshii Y Nakazora H Nomoto N Sugimoto H Nemoto H Wakata N Fujioka T Kurihara T 《Internal medicine (Tokyo, Japan)》2008,47(1):65-67
The clinical features of familial Creutzfeldt-Jakob disease with a codon 200 point mutation [fCJD (E200K)] are similar to those of sporadic CJD (sCJD). MRI diffusion-weighted imaging (MRI-DWI) has been reported to be useful for the early diagnosis of CJD. We describe a Japanese fCJD (E200K) case in which thalamic symptoms were the initial manifestations. On admission, electroencephalography (ECG) showed no periodic synchronous discharge (PSD), and MRI showed no abnormalities. However, single photon emission computed tomography (SPECT) using (99m)Tc-ethyl cysteinate dimer ((99m)Tc-ECD) revealed hypoperfusion in the right thalamus. We conclude that the thalamic form of CJD tends to show no high-intensity area (HIA) by MRI-DWI, and that SPECT may be more useful for visualizing the affected area responsible for the thalamic symptoms at an early stage. 相似文献