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61.
We investigated the effect of hypothermia on the vasodilatory response of pial arterioles to hemorrhagic hypotension. The cranial window technique was combined with microscopic video recording in an experiment involving 20 cats anesthetized with pentobarbital. The animals were randomly assigned to either a normothermic or a hypothermic group (32 degrees C). Mean arterial pressure (MAP) was reduced in stepwise increments of 10 mm Hg (from 100 to 50 mm Hg) by blood withdrawal. The diameter of small (50-100 microm) and large (100-200 microm) pial arterioles was measured. In the normothermic group (n = 9), small and large arterioles dilated at a MAP of 60 and 50 mm Hg, and at a MAP of 70, 60, and 50 mm Hg, respectively, compared with baseline values obtained at a MAP of 100 mm Hg. In contrast, in the hypothermic group (n = 11), vasodilation of either small or large arterioles was absent. The percentage diameter of small and large arterioles (percentage of control) was significantly lower at a MAP of 70, 60, and 50 mm Hg in the hypothermic group than the normothermic group. Our in vivo study demonstrates that hypothermia impairs autoregulatory vasodilation of pial arterioles in response to hemorrhagic hypotension. IMPLICATIONS: Deliberate mild hypothermia has been proposed as a means of providing cerebral protection during neurosurgical procedures. Our results suggest that cerebral blood flow autoregulation in response to hemorrhagic hypotension may be impaired during hypothermic conditions, indicating the importance of maintaining perfusion pressure during hypothermic therapy to prevent cerebral ischemia.  相似文献   
62.
We report a very rare case of primary gastric small cell carcinoma (GSCC) that was accompanied with gastric tubular adenocarcinoma. A male in his 60s had an elevated tumor with a central ulceration in the middle stomach. The patient underwent a distal gastrectomy with lymph node dissection. The pathological examination showed two separated lesions of the stomach, which contained the components of primary GSCC and primary gastric tubular adenocarcinoma. Immunohistochemical (IHC) examination demonstrated that the tumor cells in the small cell carcinoma stained positive for synaptophysin, chromogranin A, and neural cell adhesion molecule (NCAM). GSCC cells and adenocarcinoma cells independently metastasized to each regional lymph node. Further studies on the biological behavior of individual tumors may allow the development of new treatment strategies for GSCC.  相似文献   
63.
During the past 8 years 1501 colposcopies were performed paying a special attention to cervical glands for diagnosis of cervical intraepithelial neoplasia (CIN) and carcinoma. Normal openings could exclude these diseases at the error rate of only 5.1%, while atypical openings could identify them at the high confidence rate of 96.3%. False positive evaluations were mostly attributable to a marked degree of squamous metaplasia in the glands. The absence of gland openings in the main portion of the lesions amounted to 88.6% in invasive carcinomas but to only 12.4% in CIN. Adenoma malignum was a highly characteristic exception.  相似文献   
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BackgroundThe past decade has seen a substantial rise in the employment of modern data‐driven methods to study atopic dermatitis (AD)/eczema. The objective of this study is to summarise the past and future of data‐driven AD research, and identify areas in the field that would benefit from the application of these methods.MethodsWe retrieved the publications that applied multivariate statistics (MS), artificial intelligence (AI, including machine learning‐ML), and Bayesian statistics (BS) to AD and eczema research from the SCOPUS database over the last 50 years. We conducted a bibliometric analysis to highlight the publication trends and conceptual knowledge structure of the field, and applied topic modelling to retrieve the key topics in the literature.ResultsFive key themes of data‐driven research on AD and eczema were identified: (1) allergic co‐morbidities, (2) image analysis and classification, (3) disaggregation, (4) quality of life and treatment response, and (5) risk factors and prevalence. ML&AI methods mapped to studies investigating quality of life, prevalence, risk factors, allergic co‐morbidities and disaggregation of AD/eczema, but seldom in studies of therapies. MS was employed evenly between the topics, particularly in studies on risk factors and prevalence. BS was focused on three key topics: treatment, risk factors and allergy. The use of AD or eczema terms was not uniform, with studies applying ML&AI methods using the term eczema more often. Within MS, papers using cluster and factor analysis were often only identified with the term AD. In contrast, those using logistic regression and latent class/transition models were “eczema” papers.ConclusionsResearch areas that could benefit from the application of data‐driven methods include the study of the pathogenesis of the condition and related risk factors, its disaggregation into validated subtypes, and personalised severity management and prognosis. We highlight BS as a new and promising approach in AD and eczema research.  相似文献   
67.
An 80-year-old man underwent rectal resection and insertion of a central venous catheter through the left subclavian vein 16 years earlier. Following surgery, he developed edema of his left upper limb that became exacerbated and infected. Computed tomography showed occlusion of the subclavian vein and multiple arteriovenous shunts from the branches of the axillary artery to the venous sac of the axillary vein. Angiography confirmed numerous shunts between the branches of the axillary artery and vein and dilated collateral veins. Embolization of the venous sac was performed using coils, alcohol, and glue. Postprocedural angiography showed complete eradication of the nidus.  相似文献   
68.
Although hyperfunctioning mediastinal parathyroid lesions that require median sternotomy or thoracotomy for removal are occasionally present, the majority are located in the anterior mediastinum closely associated with the thymus. Only eight cases of ectopic hyperfunctioning parathyroid tumors in the middle mediastinum have been reported. We experienced two cases of either persistent or recurrent hyperparathyroidism in which abnormal parathyroid tissue was located in the aorticopulmonary window. One of the patients had a parathyroid adenoma and the other had metastatic lesions of parathyroid carcinoma. In both cases, thallium scanning proved useful in identifying the lesions while computed tomography scan was effective for mediastinal three-dimensional localization. In one case, single photon emission computed tomography imaging with thallium proved beneficial for both identification and localization of the middle mediastinal lesion. The surgical approach used in both cases was different. In one case, left thoracotomy was performed, after which the ligamentum arteriosum was divided, and an adenoma anterior to the left main bronchus and posterior to the left pulmonary artery removed. In the other case, two metastatic tumors of parathyroid carcinoma anterior to the right main bronchus and posterior to the right pulmonary artery were resected through a median sternotomy and opening of the pericardium.  相似文献   
69.
A tyrosine kinase adaptor protein containing pleckstrin homology and SH2 domains (APS) is rapidly and strongly tyrosine phosphorylated by insulin receptor kinase upon insulin stimulation. The function of APS in insulin signaling has heretofore remained unknown. APS-deficient (APS(-/-)) mice were used to investigate its function in vivo. The blood glucose-lowering effect of insulin, as assessed by the intraperitoneal insulin tolerance test, was increased in APS(-/-) mice. Plasma insulin levels during fasting and in the intraperitoneal glucose tolerance test were lower in APS(-/-) mice. APS(-/-) mice showed an increase in the whole-body glucose infusion rate as assessed by the hyperinsulinemic-euglycemic clamp test. These findings indicated that APS(-/-) mice exhibited increased sensitivity to insulin. However, overexpression of wild-type or dominant-negative APS in 3T3L1 adipocytes did not affect insulin receptor numbers, phosphorylations of insulin receptor, insulin receptor substrate-1, or Akt and mitogen-activated protein kinase. The glucose uptake and GLUT4 translocation were not affected by insulin stimulation in these cells. Nevertheless, the insulin-stimulated glucose transport in isolated adipocytes of APS(-/-) mice was increased over that of APS(+/+) mice. APS(-/-) mice also showed increased serum levels of leptin and adiponectin, which might explain the increased insulin sensitivity of adipocytes.  相似文献   
70.
Minimally invasive direct coronary artery bypass (MIDCAB) requires precise work on beating hearts and demands of surgeons' manual dexterity and mental concentration. We propose a surgical robot system that compensates for motions of organs during operations. The motion-cancelling robot system consists of three technologies: visual synchronisation, motion synchronisation and master-slave control. In this paper, we verify the effectiveness of the prototype system by an in vivo experiment.  相似文献   
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