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11.
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   
12.
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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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   
15.
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   
16.
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   
17.
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   
18.
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   
19.
韦燕玲 《广西医学》2000,22(2):249-251
目的探讨医院各区域内空气消毒效果及监测、培养所需时间.方法对3496份消毒后空气采用"平板暴露法”进行监测.第一组848份采样时平板暴露15min、置35C温箱培养48h,第二组2648份采样平板暴露5min、培养24h.结果第一组检测无菌生长率为2.6%、阳性检出率为97.4%、合格率为83.3%;第二组无菌生长率为l7.5%.阳性检出率为82.5%,合格率为88.4%.结论根据尘粒(1~10μ粒径)自然下降规律和所带细菌受损后修复需要时间,我们认为采用"平板暴露法”监测消毒后空气时以暴露15min培养48h为好.  相似文献   
20.
We used a whole cell patch clamp technique to study the effects of ropivacaine on rat dorsal horn neurons. Under voltage clamp, ropivacaine (10-400 microM) produced a dose-dependent inhibition of sodium current. From a holding potential (V(h)) of -80 mV, sodium currents evoked by test pulses to 0 mV were inhibited by ropivacaine with a mean drug concentration required to produce 50% current inhibition (IC(50)) value of 117.3 microM, which was more than the value of the bupivacaine (IC(50) 53.7 microM). The inhibition effect of ropivacaine was also voltage-dependent. Current evoked from a V(h) of -60 mV was inhibited by ropivacaine with a mean IC(50) value of 74.3 microM, which was less than that obtained at the V(h) of -80 mV. The inhibition effect of ropivacaine on sodium current was use dependent. Repeated activation by a train of depolarizing pulses (5 Hz, 20 ms) increased the inhibitory effects of ropivacaine. The ratio amplitudes of the 20th to the first pulse were 91.2% and 71.1%, respectively, in the absence and presence of ropivacaine (50 microM). Ropivacaine also produced a significant hyperpolarizing shift of 11 mV in the steady-state inactivation curve of sodium current. The inhibition of ropivacaine on the sodium channel may contribute to the mechanism of action of local anesthetics during epidural and spinal anesthesia.  相似文献   
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