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11.
目的:评估MDCT在术前耳硬化症诊断中的作用。方法:收集经临床证实为耳硬化症、且CT扫描采用螺旋扫描病例共18例,采集的数据传输到4.1工作站,进行多平面重建。结果:18例共36耳显示异常:单独前庭窗异常18耳,表现为前庭窗扩大或狭小,周围骨质密度降低或镫骨底板板密度增高;前庭窗及蜗窗同时受累共8耳;主要累及耳蜗周围迷路骨质10耳,表现为耳蜗骨迷路边缘不整,呈条片状密度减低或双环征。MPR交互重建充分显示了所有重要解剖结构的位置、形态:其中3耳为颈静脉球高位。结论:MDCT可以正确显示耳硬化症病灶的细微改变,提供详细的术前诊断信息;结合MPR技术可全面观察病变范围,并充分显示颞骨内重要解剖结构的位置和形态。对于手术方案的设计、防止手术并发症和提高疗效等具有重要意义。  相似文献   
12.
ObjectivesTo evaluate a machine learning model designed to predict mortality for Medicare beneficiaries aged >65 years treated for hip fracture in Inpatient Rehabilitation Facilities (IRFs).DesignRetrospective design/cohort analysis of Centers for Medicare & Medicaid Services Inpatient Rehabilitation Facility–Patient Assessment Instrument data.Setting and ParticipantsA total of 17,140 persons admitted to Medicare-certified IRFs in 2015 following hospitalization for hip fracture.MeasuresPatient characteristics include sociodemographic (age, gender, race, and social support) and clinical factors (functional status at admission, chronic conditions) and IRF length of stay. Outcomes were 30-day and 1-year all-cause mortality. We trained and evaluated 2 classification models, logistic regression and a multilayer perceptron (MLP), to predict the probability of 30-day and 1-year mortality and evaluated the calibration, discrimination, and precision of the models.ResultsFor 30-day mortality, MLP performed well [acc = 0.74, area under the receiver operating characteristic curve (AUROC) = 0.76, avg prec = 0.10, slope = 1.14] as did logistic regression (acc = 0.78, AUROC = 0.76, avg prec = 0.09, slope = 1.20). For 1-year mortality, the performances were similar for both MLP (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.96) and logistic regression (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.95).Conclusion and ImplicationsA scoring system based on logistic regression may be more feasible to run in current electronic medical records. But MLP models may reduce cognitive burden and increase ability to calibrate to local data, yielding clinical specificity in mortality prediction so that palliative care resources may be allocated more effectively.  相似文献   
13.
We aimed to compare intracavernosal injection (ICI), tail vein injection (IV), and periprostatic injection (PPI) of adipose-derived stem cells (ADSCs) for their ability to improve erectile function in cavernous nerve injury-induced erectile dysfunction (CNIED) rats and to explore the possible mechanism. Eighty-four male SD rats were divided into the sham group (n = 6), BCNI group (bilateral CN crush injury, n = 6), PBS-ICI group (n = 6), PBS-IV group (n = 6), PBS-PPI group (n = 6), ADSC-ICI group (n = 18), ADSC-IV group (n = 18) and ADSC-PPI group (n = 18). ADSCs were labelled with 5-ethynyl-2′-deoxyuridine (EdU), and six rats each in the ADSC-ICI group, ADSC-IV group, and ADSC-PPI group were sacrificed 2, 7, and 28 days after injection. EdU-labelled ADSCs were tracked by immunofluorescence staining. The intracavernosal pressure (ICP)/mean arterial pressure (MAP) ratio, neuronal nitric oxide synthase (nNOS)-positive nerve fibres in the dorsal penile nerve and the smooth muscle/collagen ratio in the cavernosum between groups were also evaluated. ADSCs can significantly improve erectile function through ICI or IV. The two are similar in efficacy and superior to PPI. The mechanism may be that after CN injury, ADSCs are recruited to around the MPG and secrete a variety of neurotrophic factors that promote the repair of the CN, thereby improving erectile function.  相似文献   
14.
Dai  Wei  Zhuang  Zong  Ling  Haiping  Yang  Yongbo  Hang  Chunhua 《Neurosurgical review》2021,44(1):515-527
Neurosurgical Review - To quantitatively synthesize the comparative efficacy and safety of the most common surgical approaches including endonasal transsphenoidal endoscopic surgery (ETES),...  相似文献   
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16.
The vertebral-artery-type cervical spondylosis iscommonly encountered in the middle aged and oldpeople.The author has treated 21 cases of vertebral-artery-type cervical spondylosis by acupuncture andmoxibustion,with the other 19 cases treated only byacupuncture as the controls.The results are reportedas follows.Clinical Data  相似文献   
17.
用离体豚鼠气管条,探讨侧柏叶乙酸乙酯提取物对气管平滑肌作用。结果表明,侧柏叶乙酸乙酯提取物能抑制乙酰胆碱,氯化钾所致气管平滑肌收缩,而且能使乙酰胆碱收缩气管平没肌的量效曲线右移,并抑制最大效应,其作用为剂量依赖性心肌肥厚提示侧柏叶乙酸乙酯提取物松驰气管平滑肌作用机制可能与影响Ca^2+的跨膜转运有关。  相似文献   
18.
窥镜下激光治疗前列腺增生症   总被引:2,自引:0,他引:2  
Li Q  Liu J  Xu X  Hou Z  Zhuang H  Xue J  Wang J  Cao Y 《中华外科杂志》1999,37(6):361-363
目的 评价经尿道激光前列腺切除术(TULP)的疗效及其与前列腺大小的关系。方法 回顾分析了1988年至1998年10年,采用TULP治疗的469例前列腺增生症患者对手术技术、手术前后的症关改善情况进行比较,并对233例符合条件的患者TULP手术效果与前列腺大小的相关性进行了研究。结果 469例患者前列腺症状评分(IPSS)平均值由术前的26.7降到术后的14.2;最大尿流率平均值由6.2ml/s上  相似文献   
19.
王富彬  王红 《眼科学报》1999,15(4):233-235
目的:探讨渗出型老年性黄斑变性(Age-related macular degeneration,AMD)的B型超声影象特征。方法:采用NIDEKUS-3300型超声诊断仪,对31例(54只眼)渗出型AMD进行了观察。结果:视网膜色素上皮脱离时,眼内后极部出现膜状弧形回声,光带与眼球壁之间,可见一个梭形透声区;渗出或出血未完全吸收阶段,呈混合性回声;渗出或出血逐渐吸收并为瘢痕组织所替代时,可见实体性小隆起物,强回声,形状似凸透镜或三角形,凸起端指向球后,玻璃体腔面平坦。结论:B型超声在渗出型AMD的诊断、治疗随访观察中具有实用价值。眼科学报1999;15:233-235。  相似文献   
20.
Abstract: Earlier work in this laboratory showed that amiodarone induces apoptosis in alveolar epithelial cells by a mechanism inhibitable by angiotensin system antagonists. A variety of recent studies suggests a critical role for alveolar epithelial cell apoptosis in the pathogenesis of lung fibrosis. On this basis we hypothesized that amiodarone‐induced alveolar epithelial cell apoptosis and lung fibrosis in vivo might be inhibitable by the angiotensin converting enzyme inhibitor captopril or the angiotensin receptor antagonist losartan. Amiodarone‐induced lung fibrosis was induced in male Wistar rats by oral adminstration over six months. Replicate groups of rats received captopril or losartan in addition to amiodarone. Apoptosis was detected by increased total lung activity of caspase 3 and in situ end labeling (ISEL) of fragmented DNA. Collagen was localized and quantitated by the picrosirius red technique. Alveolar epithelial cell apoptosis was detected in amiodarone‐treated animals as early as three weeks after the start of amiodarone administration; by six months exposure, the incidence of alveolar epithelial cell apoptosis was significantly reduced by coadministration of captopril or losartan. Alveolar wall collagen accumulation also was significantly attenuated by captopril (100%) or losartan (74%), but neither agent blunted the accumulation of alveolar macrophages evoked by amiodarone (5.3‐fold at 6 months). Lung neutrophil content was unchanged by amiodarone treatment for three weeks or six months. These results indicate that amiodarone induces alveolar epithelial cell apoptosis in vivo that is inhibitable by angiotensin antagonists. They also support the hypothesis that blockade of angiotensin formation or function attenuates amiodarone‐induced lung fibrosis irrespective of the severity of alveolitis.  相似文献   
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