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排序方式: 共有1874条查询结果,搜索用时 15 毫秒
21.
22.
Miyashita N Fukano H Hara H Yoshida K Niki Y Matsushima T 《Internal medicine (Tokyo, Japan)》2002,41(1):30-33
Two cases of recurrent pneumonia due to Chlamydia pneumoniae are described. C. pneumoniae was continuously detected from the nasopharynx in both patients by the polymerase chain reaction and/or culture even with appropriate antibiotic therapy during the first episode. After eradication of C. pneumoniae with long-term macrolide therapy, the respiratory symptoms of both patients completely disappeared and no relapse was observed. These data indicate that new treatment strategies may be necessary to eradicate the organism in patients prone to persistent infection. 相似文献
23.
Makoto Seki Akio Yanagisawa Eiji Ninomiya Yasuro Ninomiya Hirotoshi Ohta Akio Saiura Junji Yamamoto Toshiharu Yamaguchi Akiko Aruga Keiko Yamada Koichi Takano Rikiya Fujita Masayuki Ikeda Keiko Sasaki Yo Kato 《Journal of hepato-biliary-pancreatic sciences》2005,12(3):254-262
Background/Purpose
Between 1988 and 2003, 38 patients underwent biliary resection for pancreaticobiliary maljunction (PBM). We reviewed the histopathologic findings for the surgically resected specimens to compare the clinical and pathologic features and assess the relationship between changes in the background biliary epithelium and the development of neoplasms.Methods
Papillary hyperplasia (PHP) seen in the biliary epithelium of patients with PBM, was classified into grades 0–III in the gallbladder and grades 0–II in the extrahepatic bile duct, according to the extent, and was assessed for links with tumors in the same specimens.Results
The incidence of gallbladder carcinoma was 13/21 in grades I–II, versus 0/16 in grade III, while the incidence of bile duct carcinoma was 4/20 in grade I versus 0/5 in grade II. Furthermore, these incidences for patients below age 50 years and age 50 or older were 1/18 versus 12/20, and 0/14 versus 6/17, respectively.Conclusions
PHP of the biliary epithelium in PBM patients is an important precursor lesion, especially for gallbladder cancer, and the risk becomes greater with age, regardless of the type of pancreatobiliary junction (PBJ) and its location in the biliary tract. 相似文献24.
Hypoxia‐inducible factor‐3α promotes angiogenic activity of pulmonary endothelial cells by repressing the expression of the VE‐cadherin gene
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25.
Mitome N Suzuki T Hayashi S Yoshida M 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(33):12159-12164
In a rotary motor F(o)F(1)-ATP synthase that couples H(+) transport with ATP synthesis/hydrolysis, it is thought that an F(o)c subunit oligomer ring (c-ring) in the membrane rotates as protons pass through F(o) and a 120 degrees rotation produces one ATP at F(1). Despite several structural studies, the copy number of F(o)c subunits in the c-ring has not been determined for any functional F(o)F(1). Here, we have generated and isolated thermophilic Bacillus F(o)F(1), each containing genetically fused 2-mer-14-mer c (c(2)-c(14)). Among them, F(o)F(1) containing c(2), c(5), or c(10) showed ATP-synthesis and other activities. When F(1) was removed, F(o) containing c(10) worked as an H(+) channel but F(o)s containing c(9), c(11) or c(12) did not. Thus, the c-ring of functional F(o)F(1) of this organism is a decamer. The inevitable consequence of this finding is noninteger ratios of rotation step sizes of F(1)/F(o) (120 degrees /36 degrees ) and of H(+)/ATP (10:3). This step-mismatch necessitates elastic twisting of the rotor shaft (and/or the side stalk) during rotation and permissive coupling between unit rotations by H(+) transport at F(o) and elementary events in catalysis at F(1). 相似文献
26.
Nicola Baldini Katia Scotlandi Massimo Serra Katsuyuki Kusuzaki Toshiharu Shikita Maria C. Manara Daniela Maurici Mario Campanacci 《Journal of cancer research and clinical oncology》1992,119(2):121-126
Summary The reliability of a simple method evaluating the pattern of subcellular binding of Adriamycin (Adriamycin binding assay, ABA) as an index of sensitivity was demonstrated in different primary cultures and in sensitive and resistant cell lines of human osteosarcoma. After exposure to Adriamycin (10 g/ml for 30 min at 37°C), living sensitive cells showed selective intranuclear uptake of the drug, whereas in resistant cells no distinct subcellular distribution was observed. The binding pattern of Adriamycin in sensitive and in highly resistant cells was inversely related to the expression of P-glycoprotein. However, low levels of resistance in vitro, not detectable by increased levels of expression of P-glycoprotein, were revealed by ABA. The use of ABA in combination with the estimate of P-glycoprotein expression is recommended in clinical practice as an accurate means for predicting the sensitivity of osteosarcoma to Adriamycin.This study was supported by a grant from the Associazione Italiana per la Ricerca sul Cancro (A.I.R.C.). 相似文献
27.
Clinical presentation of community-acquired Chlamydia pneumoniae pneumonia in adults 总被引:1,自引:0,他引:1
STUDY OBJECTIVE: To investigate the clinical presentation of community-acquired Chlamydia pneumoniae pneumonia in adults. DESIGN: Prospective study. SETTING: Kawasaki Medical School Hospital, Kawasaki Medical School Kawasaki Hospital, and Kurashiki Daiichi Hospital in Japan. PARTICIPANTS: Forty patients with community-acquired pneumonia with C pneumoniae as the only pathogen identified admitted to three hospitals between April 1996 and March 2001 and their clinical presentations were compared to patients with Streptococcus pneumoniae and Mycoplasma pneumoniae pneumonia. MEASUREMENTS: The diagnosis of C pneumoniae infection was based on isolation and serologic testing of antibodies by the microimmunofluorescence test. RESULTS: The clinical presentations, except for shortness of breath, were similar for the three major etiologic agents. The mean temperature of C pneumoniae patients on hospital admission was 37.9 degrees C, which was lower than that of patients with S pneumoniae and M pneumoniae. The mean WBC count on hospital admission was lower in the patients with C pneumoniae (mean, 9,100/microL) than in those with S pneumoniae pneumonia but higher than in those with M pneumoniae pneumonia. No patients required respiratory support or admission to an ICU, and no deaths occurred among the C pneumoniae pneumonia patients. CONCLUSIONS: Our results indicate that C pneumoniae pneumonia as a single etiologic agent is mild and that the underlying conditions and clinical symptoms closely resemble those of S pneumoniae pneumonia. However, the physical examinations, laboratory findings, and prognostic factors of the C pneumoniae patients resembled those of patients with M pneumoniae pneumonia. 相似文献
28.
OBJECTIVE: The aim of this study was to evaluate the clinicopathological features of lung cancer resembling malignant pleural mesothelioma. METHODOLOGY: The seven patients studied had tumours showing an extensive pleural growth pattern, and were chosen from 1516 lung cancer patients diagnosed at two affiliated hospitals over a 17-year period. RESULTS: Histologically, five of these lung cancers were adenocarcinomas, one was a small cell carcinoma, and one a large cell carcinoma. Tumour markers such as carcinoembryonic antigen (CEA) were elevated in six patients at admission. However, a clinical diagnosis was difficult and these cancers could only be distinguished from malignant pleural mesothelioma by thoracentesis in two cases, pleural biopsy in two, thoracotomy in two, and in case 7 at autopsy. Treatment consisted of chemotherapy or radiation therapy in four patients, but with little clinical effect. The mean survival time was 6.7 months, which is much less than for true malignant pleural mesothelioma. CONCLUSIONS: Lung cancer resembling malignant pleural mesothelioma is most frequently observed in patients with adenocarcinoma, which is suspected to occur peripherally. To distinguish pseudomesotheliomatous carcinoma from malignant pleural mesothelioma in patients with diffuse pleural thickening and effusion, requires adequate tissue sampling by thoracotomy or video-assisted thoracoscopic surgery and a panel of immunohistochemical stains. 相似文献
29.
Karin Ashizawa Kanako Ogura Shunsuke Nagase Asumi Sakaguchi Joji Tokugawa Makoto Hishii Masaharu Fukunaga Takanori Hirose Toshiharu Matsumoto 《Pathology international》2021,71(10):697-706
An intracranial collision tumor is a rare lesion composed of two histologically different neoplasms in the same anatomic location. Even more rare is the collision tumor of a solitary fibrous tumor/hemangiopericytoma (SFT/HPC) and meningioma. The patient was a 46-year-old woman who had a 40 × 35 × 30-mm mass in the vermis of the cerebellum. Histologically, the mass consisted of two different components. One component showed the morphology of meningioma (World Health Organization (WHO) grade I), and the other component exhibited small round cell proliferation with hypercellular density, which was revealed to be SFT/HPC (WHO grade III) based on STAT6 immunohistochemistry. STAT6 showed completely different immunohistochemistry results in these two components (nuclear-negative in meningioma and nuclear-positive in SFT/HPC). Since these two neoplasms are associated with different prognoses, they should be distinguished from each other. When meningioma and an SFT/HPC-like lesion are identified morphologically, it is important to recognize the presence of such a collision tumor composed of meningioma and SFT/HPC, and identify the SFT/HPC component by employing STAT6 immunohistochemistry. 相似文献
30.
Yoshifumi Noda Nobuyuki Kawai Takuma Ishihara Yoshiki Tsuboi Tetsuro Kaga Toshiharu Miyoshi Fuminori Hyodo Masayuki Matsuo 《The British journal of radiology》2021,94(1122)
Objectives:To determine the optimal scan delay corresponding to individual hemodynamic status for pancreatic parenchymal phase in dynamic contrast-enhanced CT of the abdomen.Methods:One hundred and fourteen patients were included in this retrospective study (69 males and 45 females; mean age, 67.9 ± 12.1 years; range, 39–87 years). These patients underwent abdominal dynamic contrast-enhanced CT between November 2019 and May 2020. We calculated and recorded the time from contrast material injection to the bolus-tracking trigger of 100 Hounsfield unit (HU) at the abdominal aorta (s) (TimeTRIG) and scan delay from the bolus-tracking trigger to the initiation of pancreatic parenchymal phase scanning (s) (TimeSD). The scan delay ratio (SDR) was defined by dividing the TimeSD by TimeTRIG. Non-linear regression analysis was conducted to assess the association between CT number of the pancreas and SDR and to reveal the optimal SDR, which was ≥120 HU in pancreatic parenchyma.Results:The non-linear regression analysis showed a significant association between CT number of the pancreas and the SDR (p < 0.001). The mean TimeTRIG and TimeSD were 16.1 s and 16.8 s, respectively. The SDR to peak enhancement of the pancreas (123.5 HU) was 1.00. An SDR between 0.89 and 1.18 shows an appropriate enhancement of the pancreas (≥120 HU).Conclusion:The CT number of the pancreas peaked at an SDR of 1.00, which means TimeSD should be approximately the same as TimeTRIG to obtain appropriate pancreatic parenchymal phase images in dynamic contrast-enhanced CT with bolus-tracking method.Advances in knowledge:The hemodynamic state is different in each patient; therefore, scan delay from the bolus-tracking trigger should also vary based on the time from contrast material injection to the bolus-tracking trigger. This is necessary to obtain appropriate late hepatic arterial or pancreatic parenchymal phase images in dynamic contrast-enhanced CT of the abdomen. 相似文献