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141.
Hiroki Sato rew Scott Liss Yusuke Mizukami 《World journal of gastroenterology : WJG》2021,27(23):3262-3278
Pancreatic cancer currently has no subtypes that inform clinical decisions; hence, there exists an opportunity to rearrange the morphological and molecular taxonomy that guides a better understanding of tumor characteristics. Nonethe less, accumulating studies to date have revealed the large-duct type variant, a unique subtype of pancreatic ductal adenocarcinoma (PDA) with cystic features. This subtype often radiographically mimics intraductal papillary mucinous neoplasms (IPMNs) and involves multiple small cysts occasionally associated with solid masses. The “bunch-of-grapes” sign, an imaging characteristic of IPMNs, is absent in large-duct PDA. Large-duct PDA defines the mucin profile, and genetic alterations are useful in distinguishing large-duct PDA from IPMNs. Histologically, neoplastic ducts measure over 0.5 mm, forming large ductal elements. Similar to classic PDAs, this subtype is frequently accompanied by perineural invasion and abundant desmoplastic reactions, and KRAS mutations in codon 12 are nearly ubiquitous. Despite such morphological similarities with IPMNs, the prognosis of large-duct PDA is equivalent to that of classic PDA. Differential diagnosis is therefore essential. 相似文献
142.
Toshihiro Nakamura MD Kunihiko Kiuchi MD FHRS Koji Fukuzawa MD Mitsuru Takami MD Yoshiaki Watanabe MD Yu Izawa MD Hideya Suehiro MD Tomomi Akita MD Makoto Takemoto MD Jun Sakai MD Atsusuke Yatomi MD Yusuke Sonoda MD Hiroyuki Takahara MD Kazutaka Nakasone MD Kyoko Yamamoto MD Noriyuki Negi RT Atsushi Kono MD Takashi Ashihara MD PhD Ken-ichi Hirata MD PhD 《Journal of cardiovascular electrophysiology》2021,32(4):1005-1013
143.
A 77-year-old man hospitalized in a bedridden state for cerebral infarction and left hemiparesis experienced the sudden onset of dyspnea and cyanosis. Chest X-ray films detected a foreign object in the hilum of the left lung. Emergency bronchoscopy revealed a dental crown lodged in the second carina. It was not possible to remove the crown with bronchoscopy forceps. The patient suffered severe respiratory failure the following day. Bronchoscopy again was performed, and the foreign object was removed with basket-type forceps. It was the patient's first molar, covered with a crown. The patient's respiratory failure was caused by atelectasis of the left lower lobe and overinflation, of the right lung, both of which resulted from postoperative edema of bronchial mucous membrane. Dental foreign objects do not cause pulmonary atelectasis or pneumonia as easily as other types of bronchial foreign objects. Therefore, there is usually enough time for thorough examination prior to removal procedures. It is important to accurately identify the shape of the foreign object, choose appropriate forceps, and successfully remove the object in the first operation. Moreover, adequate dental treatment of caries and loose teeth is important as a means of preventing dental foreign objects, especially in elderly people and bedridden patients. 相似文献
144.
Normal ultrasonic myocardial reflectivity in athletes with increased left ventricular mass. A tissue characterization study. 总被引:4,自引:0,他引:4
F Lattanzi V Di Bello E Picano M T Caputo L Talarico C Di Muro L Landini G Santoro C Giusti A Distante 《Circulation》1992,85(5):1828-1834
BACKGROUND. Ultrasonic integrated backscatter of myocardial walls is directly related to the morphometrically evaluated collagen content. The integrated backscatter is also increased in hypertrophic cardiomyopathy, probably because of fiber disarray. The purpose of this study was to investigate myocardial tissue reflectivity in subjects with physiological hypertrophy caused by intense physical training and to assess the relation between the acoustic properties of myocardial tissue and left ventricular wall thickness assessed by conventional two-dimensional echocardiography. METHODS AND RESULTS. Twenty-four young male athletes (14 professional cyclists and 10 weight lifters, all in full agonistic activity) were studied together with 10 normal age-matched controls with sedentary life. By means of a commercially available two-dimensional echocardiograph, standard measurements were obtained according to the recommendations of the American Society of Echocardiography. With a prototype implemented in our Institute, an on-line radiofrequency analysis of ultrasound signals was also performed to obtain quantitative operator-independent measurements of the integrated backscatter of the myocardial walls. The integrated values of the radiofrequency signal were normalized for the pericardial interface and expressed in percent integrated backscatter (%IB). Compared with control subjects, athletes showed greater thickness values of septum (controls, 9 +/- 1; cyclists, 14 +/- 2; weight lifters, 15 +/- 1 mm, mean +/- SD; p less than 0.01) and posterior wall (9 +/- 1, 12 +/- 2, and 12 +/- 1 mm, respectively; p less than 0.01) but similar values of %IB for both septum (23 +/- 4%, 21 +/- 7%, and 23 +/- 8%, p = NS) and posterior wall (10 +/- 2%, 9 +/- 2%, and 11 +/- 2%, p = NS). In athletes, no correlation was found between septal and posterior wall thickness and the corresponding regional myocardial reflectivity (r = 0.23, p = NS and r = 0.01, p = NS, respectively). Furthermore, we compared the quantitative ultrasonic data between two subsets of 10 athletes and 10 patients with hypertrophic cardiomyopathy and similar degrees of septal thickness (16 +/- 1 versus 17 +/- 1 mm, respectively, p = NS). Septal and posterior wall %IB results were significantly higher in patients with hypertrophic cardiomyopathy (53 +/- 13% and 36 +/- 9%, respectively) than in athletes (21 +/- 7% and 10 +/- 3%, respectively; p less than 0.01 for both). CONCLUSIONS. We conclude that 1) endurance athletes show a normal pattern of quantitatively assessed ultrasonic backscatter despite of a marked left ventricular hypertrophy and 2) athletes and patients with hypertrophic cardiomyopathy and similar degrees of myocardial wall thickness can be differentiated on the basis of quantitative analysis of backscattered signal. 相似文献
145.
146.
147.
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
148.
149.
Akutsu Y Shinozuka A Kodama Y Li HL Kayano H Hamazaki Y Yamanaka H Katagiri T 《Japanese heart journal》2004,45(2):195-204
The optimal diagnostic approaches using contractile reserve, perfusion, and free fatty acid metabolism together for identifying myocardial stunning after reperfusion have not been clarified in the clinical setting. We investigated the usefulness of simultaneous evaluation of these parameters during myocardial stunning to predict the functional recovery in infarct-related myocardium after reperfusion. In 43 patients (60.7 +/- 10.4 years) with successful coronary angioplasty early after a first myocardial infarction, low-dose (5 to 10 microg/kg/min) dobutamine stress thallium-201/iodine-123 beta-methyl-iodophenyl pentadecanoic acid (BMIPP) dual-isotope single photon emission computed tomography was performed with echocardiography in the acute phase within 1 week after reperfusion. Regional wall motion and the uptake of each tracer were obtained simultaneously in the infarct-related segments. In 93 segments with dyssynergy in the acute phase after reperfusion, the sensitivity, specificity, and accuracy using contractile reserve for predicting the final functional recovery in the chronic phase more than 3 months after PTCA were 81.3%, 67.2%, and 72%, respectively. More accurate predictions were obtained by simultaneous measurements of thallium-201 and BMIPP uptakes (93.8%, 66.7%, and 79.4%, respectively). The final functional recovery in the stunned myocardium after early reperfusion following acute myocardial infarction was predicted more accurately by simultaneous evaluation of these parameters at dobutamine stress testing. 相似文献
150.
Higashiura Masaki Ohya Masaki Tanaka Yusuke Yano Takuro Yamamoto Shuto Mima Toru Negi Shigeo Shigematsu Takashi 《International journal of clinical pharmacy》2020,42(2):635-641
International Journal of Clinical Pharmacy - Background Renal anaemia worsens because of the uraemic status immediately before the initiation of haemodialysis. The haemoglobin level in patients... 相似文献