The rotary left ventricular assist device (LVAD) has been an effective option for end-stage heart failure. However, while clinically using the LVAD, patients are often at significant risk for ventricular collapse, called suction, mainly due to higher LVAD speeds required for adequate cardiac output. Some proposed suction detection algorithms required the external implantation of sensors, which were not reliable in long-term use due to baseline drift and short lifespan. Therefore, this study presents a new suction detection system only using the LVAD intrinsic blood pump parameter (pump speed) without using any external sensor. Three feature indices are derived from the pump speed and considered as the inputs to four different classifiers to classify the pumping states as no suction or suction. The in-silico results using a combined human circulatory system and LVAD model show that the proposed method can detect ventricular suction effectively, demonstrating that it has high classification accuracy, stability, and robustness. The proposed suction detection system could be an important part in the LVAD for detecting and avoiding suction, while at the same time making the LVAD meet the cardiac output demand for the patients. It could also provide theoretical basis and technology support for designing and optimizing the control system of the LVAD.
Objective To determine the effects of controlled hypotension (CH) on cerebra1 blood flow, cerebra1metabolism, and cognitive functions. Methods Randomized controlled trials (RCTs) were identified from MEDLINE (1966 to 2008), EMbase (1974 to 2008), The Cochrane Library (Issue 2, 2008), CBM (1978 to 2008), and CNKI (1994 to 2008). The quality of included trials was assessed by two reviewers independently. RevMan 4.2.7 software provided by The Cochrane Collaboration was used for statistical analysis. Results Nine RCTs involving a total of 295 patients were included. Most of the studies were of poor methodological quality. Meta-analysis was performed because the outcomes were the comparisons of the means of several repeated measures, and so a descriptive analysis was conducted. There were no significant differences in cerebral blood flow velocity, hypoxia-induced metabolites, and cognitive function between the CH group and the control group (Plt;0.05). But the S100B protein level in cerebrospinal fluid or blood was significantly higher in the CH group than that in the control group (Plt;0.02). Conclusion CH has no adverse effects on cerebra1 blood flow, cerebra1 metabolism, or cognitive functions. But isoflurane-induced hypotension may increase the release of S100B, indicating worse brain injury. The above conclusions were made from the limited evidence, and more rigorous RCTs are needed.
【摘要】 目的 探讨高频彩色多普勒超声对浅表软组织肿物的诊断价值。 方法 回顾性分析2008年1-11月70例经手术、活检病理证实的浅表软组织肿物的声像图特征，包括肿物的部位、形态大小、内部回声、边界及其与周边组织的关系、长径与厚度比值（L/T）及病变周边与内部血流分布情况。 结果 超声对浅表肿块病灶的显示率为100%，良性肿瘤有脂肪瘤、表皮囊肿、滑膜囊肿、神经鞘瘤，血管瘤、异物肉芽肿等，恶性肿物包括皮肤纤维肉瘤，转移性腺癌。 结论 彩色多普勒超声对浅表肿块的检出、定位及物理性质可做出准确的诊断，综合分析肿物的边界、形态、内部回声及血流分布等特点对肿物的良恶性诊断具有重要价值。【Abstract】 Objective To evaluate the value of high-frequency color Doppler ultrasonography in diagnosing the superficial soft tissue masses. Methods The clinical data of 70 patients with superficial soft tissue masses from January to November 2008 were retrospectively analyzed. Superficial soft tissue masses was diagnosed by the surgery and biopsy. The sonographic features, including the location, morphology, size, internal echo, boundary, relationship with peripheral tissues, longitude to transverse ratio (L/T), and the vascularity, were observed. Results The results of sonographic examination showed that 100% superficial masses could be found. Benign masses included lipoma, sebaceous cysts, synovial cysts, nerve sheath tumors, haemangioma, foreign body granulomas, etc. Malignant soft tissue tumors included fibrous sarcoma and metastatic neoplasms. Conclusion Color Doppler ultrasonography can precisely diagnose the presence, localization and the physical characters of superficial soft tissue masses. It is an excellent modality to diagnose the benign or malignant masses by analyzing the boundary, configuration, internal echo and vascularity of the masses.
ObjectiveTo study the relationship between hepatocellular apoptosis and glycogen contents during hepatic cold preservationreperfusion and its mechanism.MethodsBased on the model of four groups of rabbit livers with different hepatocellular glycogen contents, hepatocellular apoptosis and bax gene expression were observed during hepatic cold preservationreperfusion.ResultsApoptotic hepatocytes were obviously found in 60 minute reperfusing livers subsequent to 9 hour cold storage, and there was significant difference in the numbers of apoptotic hepatocytes among all the groups. In the same time, there was the close relationship between the levels of bax gene expression and the glycogen contents of hepatocytes.ConclusionIntracellular abundant glycogen may significantly depress the hepatocellular apoptosis during hepatic cold preservationreperfusion by decreasing hepatocellular bax gene expression.
Objective To review the research progress of C terminal propeptide of collagen type II (CTX-II), a osteoarthritis (OA) biomarker. Methods Domestic and international l iterature about CTX-II was reviewed extensively and summarized. Results CTX-II is investigated broadly and has the best performance of all currently available biomarkers. CTX-II is a truly useful biomarker for early diagnosis, prognosis, and measurement of treatment response in OA. Conclusion Single CTX-II may be not sufficient for early diagnosis and prognosis of OA, so a combination of CTX-II and other biomarkers or diagnosis methods is needed.
Objective To review the research progress of cartilage ol igomeric matrix protein (COMP). Methods Domestic and abroad l iterature about COMP was reviewed and summarized. Results COMP was one of the osteoarthritis (OA) biomarkers of being widely studied. Most studies in recent years could draw the conclusion that COMP was associated with OA. COMP was the foremost biomarker among investgated biomarkers. It could been continuously expressed and predicted knee OA progression. Conclusion Precisely what role COMP plays in OA pathogenesis remains unclear, using COMP as a tool to early diagnose OA more studies would be needed.
Objective To investigate the effects of myopia on first-order kernels six ring responses of multifocal electroretinogram (mfERG). Method We continuously selected 80 subjects aged from 13 to 20 year-old and divided four groups into normal, mild myopia, moderate myopia and high myopia. Each group had 20 subjects that were examined with mfERG of 103 stimuli locations. The amplitude and latency of N1, P1, N2 waveforms of six-ring first-kernel responses in mfERG were analyzed. Result With increasing of myopia degree, the response density of N1, P1, N2 waveforms of six-ring first-kernel responses in mfERG was decreased gradually (all Plt;0.05). However, latency of N1, P1, N2 waveforms of six-ring first-kernel responses in mfERG didnrsquo;t change significantly (all Pgt;0.05). Conclusion Myopia can decrease the response density of first-order kernels six ring responses of mfERG, which is very important to determine the abnormality of mfERG in the clinic. (Chin J Ocul Fundus Dis, 2006, 22, 103-105)
【摘要】 目的 探讨彩色多普勒超声对临床甲状腺良恶性结节的诊断价值。 方法 对2007-2010年105例经手术病理证实的甲状腺结节患者资料进行回顾性分析，总结其声像图特征。 结果 105例患者中，良性结节71例，甲状腺癌34例，超声诊断符合率81.9%，误诊18例（17.1%）。 结论 彩色多普勒超声是诊断甲状腺结节的首选影像学检查方法，但对良恶性结节的鉴别及微小癌的诊断有局限性。【Abstract】 Objective To evaluate the value of color Doppler flow imaging in diagnosis of benign and malignant thyroid nodules. Methods We retrospectively analyzed the clinical data of 105 patients with thyroid nodules confirmed by pathology between 2007 and 2010 and summarized the ultrasonography results. Results Among the 105 cases, 71 were benign nodules and 34 were malignant tumors. The overall diagnostic accordance rate was 81.9% with 18 cases (17.1%) of misdiagnosis. Conclusion Ultrasonography is the first imaging modality for thyroid nodule examination, but it is limited in the diagnosis of microcarcinoma and in distinguishing malignant from benign nodules in the same thyroid.