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Solitary bronchioloalveolar carcinoma: CT criteria   总被引:14,自引:0,他引:14  
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis.  相似文献   
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To control intraoperative bleeding is an important key to successful endoscopic submucosal dissection. The distribution of submucosal vessels encountered during the procedure differ in places in the stomach and are roughly categorized into three groups: those located in the antrum, those in the lesser curvature, and those on the anteroposterior corpus wall which consists of oblique muscle layers. Therefore, knowledge of a suitable setting of diathermy and adjusted depth of dissection in the submucosal layer for each site is imperative. The combination of utilizing the distal attachment forced or swift coagulation (trimming with coagulation mode) have enable the treatment with an insulation tipped knife safer.  相似文献   
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Background: Anesthetics inhibit airway smooth muscle contraction in part by a direct effect on the smooth muscle cell. This study tested the hypothesis that the anesthetics halothane and hexanol, which both relax airway smooth muscle in vitro, inhibit acetylcholine-promoted nucleotide exchange at the [alpha] subunit of the Gq/11 heterotrimeric G protein (G[alpha]q/11; i.e., they inhibit muscarinic receptor-G[alpha]q/11 coupling).

Methods: The effect of halothane (0.38 +/- 0.02 mm) and hexanol (10 mm) on basal and acetylcholine-stimulated G[alpha]q/11 guanosine nucleotide exchange was determined in membranes prepared from porcine tracheal smooth muscle. The nonhydrolyzable, radioactive form of guanosine-5'-triphosphate, [35S]GTP[gamma]S, was used as the reporter for G[alpha]q/11 subunit dissociation from the membrane to soluble fraction, which was immunoprecipitated with rabbit polyclonal anti-G[alpha]q/11 antiserum.

Results: Acetylcholine caused a significant time- and concentration-dependent increase in the magnitude of G[alpha]q/11 nucleotide exchange compared with basal values (i.e., without acetylcholine), reaching a maximal difference at 100 [mu]m (35.9 +/- 2.9 vs. 9.8 +/- 1.2 fmol/mg protein, respectively). Whereas neither anesthetic had an effect on basal G[alpha]q/11 nucleotide exchange, both halothane and hexanol significantly inhibited the increase in G[alpha]q/11 nucleotide exchange produced by 30 [mu]m acetylcholine (by 59% and 68%, respectively).  相似文献   

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The gastric vasculature responsible for intraoperative bleeding in endosocpic submucosal dissection (ESD) is the ramified vascular network occupying the middle of the submucosal layer and large vessels penetrating the muscle layer. Appropriate management for these vessels must be addressed. The trimming of the ramified vascular network can be safely performed with coagulation mode following shallow mucosal cutting. A large penetrating vessel usually requires precoagulation prior to dissection. These procedures are effectively performed with the water jet short needle knife (Flush knife).  相似文献   
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Progressive multifocal leukoencephalopathy (PML) is a fetal demyelinating disease in the central nervous system. PML was once a rare disease, but it is now relatively common among AIDS (acquired immunodeficiency syndrome) patients. The immunological state of patients mainly contributes to the pathogenesis of PML. Genetic changes of the etiological agent, however, may also be involved in the development and progression of the disease. The major genetic changes possibly associated with PML include the regulatory region rearrangement and the VP1 loop mutation. Both changes have been identified as genetic changes usually occurring in JCV (JCvirus) DNAs from the brain and cerebrospinal fluid of PML patients. Although it remained to be clarified how these changes are involved in the pathogenesis of PML, accumulating evidence suggests that the VP1 loop mutation is associated with the progression of PML. Here we overview studies (mainly those performed by ourselves) on these genetic changes.  相似文献   
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