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Aims: In neuropsychological evaluations, it is often difficult to ascertain whether poor performance on measures of validity is due to poor effort or malingering, or whether there is genuine cognitive impairment. Dunham and Denney created an algorithm to assess this question using the Medical Symptom Validity Test (MSVT). We assessed the ability of their algorithm to detect poor validity versus probable impairment, and concordance of failure on the MSVT with other freestanding tests of performance validity.

Methods: Two previously published datasets (n?=?153 and n?=?641, respectively) from outpatient neuropsychological evaluations were used to test Dunham and Denney’s algorithm, and to assess concordance of failure rates with the Test of Memory Malingering and the forced choice measure of the California Verbal Learning Test, two commonly used performance validity tests.

Results: In both datasets, none of the four cutoff scores for failure on the MSVT (70%, 75%, 80%, or 85%) identified a poor validity group with proportionally aligned failure rates on other freestanding measures of performance validity. Additionally, the protocols with probable impairment did not differ from those with poor validity on cognitive measures.

Conclusions: Despite what appeared to be a promising approach to evaluating failure on the easy MSVT subtests when clinical data are unavailable (as recommended in the advanced interpretation program, or advanced interpretation [AI], of the MSVT), the current findings indicate the AI remains the gold standard for doing so. Future research should build on this effort to address shortcomings in measures of effort in neuropsychological evaluations.  相似文献   

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Inbred mouse strains are the most widely used mammalian model organism in biomedical research owing to ease of genetic manipulation and short lifespan; however, each inbred strain possesses a unique repertoire of deleterious homozygous alleles that can make a specific strain more susceptible to a particular disease. In the current study, we report dystrophic cardiac calcinosis (DCC) in C.B‐17 SCID male mice at 10 weeks of age with no significant change in cardiac function. Acquisition of DCC was characterized by myocardial injury, fibrosis, calcification, and necrosis of the tissue. At 10 weeks of age, 38% of the C.B‐17 SCID mice from two different commercial colonies exhibited significant calcinosis on the ventricular epicardium, predominantly on the right ventricle. The frequency of calcinosis was more than 50% for mice obtained from Taconic's Cambridge City colony and 25% for mice obtained from Taconic's German Town colony. Interestingly, the DCC phenotype did not affect cardiac function at 10 weeks of age. No differences in echocardiography or electrocardiography were observed between the calcinotic and non‐calcinotic mice from either colony. Our findings suggest that C.B‐17 SCID mice exhibit DCC as early as 10 weeks of age with no significant impact on cardiac function. This strain of mice should be cautiously considered for the study of cardiac physiology.  相似文献   
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目的探讨T3、T4期结直肠癌患者淋巴结转移危险因素,为临床诊疗提供参考。方法回顾性分析2008年1月至2017年12月在空军军医大学西京消化病医院行结直肠癌根治术的1112例T3、T4期结直肠癌患者的临床病理资料,分析淋巴结转移状态与临床病理因素及肿瘤标志物的相关性,应用logistic多因素回归法分析淋巴结转移的相关危险因素。结果单因素分析结果显示,性别、年龄、肿瘤部位分层的结直肠癌患者间淋巴结转移率差异均无统计学意义(均P>0.05),淋巴结转移率在不同肿瘤长径[<5 cm和≥5 cm分别为37.75%(211/559)、52.26%(289/553),χ^2=23.666,P<0.01]、大体类型[浸润、溃疡、蕈伞、隆起分别为37.04%(20/54)、47.52%(432/909)、34.33%(23/67)、69.51%(57/82),χ^2=13.787,P=0.003]、分化程度[高、中、低分化分别为34.11%(102/299)、49.00%(317/647)、48.80%(81/166),χ^2=19.771,P<0.01]、错配修复缺陷(dMMR)[是和否分别为26.34%(64/243)、50.17%(436/869),χ^2=43.996,P<0.01]、神经侵犯[是和否分别为48.17%(421/874)、33.20%(79/238),χ^2=16.954,P<0.01]、脉管侵犯[是和否分别为79.16%(338/427)、23.65%(162/685),χ^2=327.493,P<0.01]以及术前癌胚抗原(CEA)[阳性(≥5 mg/ml)和阴性(<5 mg/ml)分别为52.87%(249/471)、39.16%(251/641),χ^2=20.162,P<0.01]和CA199[阳性(≥35 U/ml)和阴性(<35 U/ml)分别为59.33%(124/209)、41.64%(376/903),χ^2=21.465,P<0.01]分层患者间差异均有统计学意义。logistic多因素回归分析显示,脉管侵犯和术前CA199阳性是T3、T4期结直肠癌患者淋巴结转移独立危险因素(OR=13.006,95%CI 9.329~17.276,P<0.01;OR=2.194,95%CI 1.513~3.181,P<0.01),dMMR阳性是淋巴结转移的保护性因素(OR=0.279,95%CI 0.190~0.411,P<0.01)。结论脉管侵犯是T3、T4期结直肠癌患者淋巴结转移的主要危险因素。术前肿瘤标志物CA199的检测可以作为预测T3、T4期结直肠癌患者淋巴结转移状态的指标,一定程度上可为诊疗方案的制订提供参考。  相似文献   
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Background

Partial nephrectomy (PN) is generally favored for cT1 tumors over radical nephrectomy (RN) when technically feasible. However, it can be unclear whether the additional risks of PN are worth the magnitude of renal function benefit.

Objective

To develop preoperative tools to predict long-term estimated glomerular filtration rate (eGFR) beyond 30 d following PN and RN, separately.

Design, setting, and participants

In this retrospective cohort study, patients who underwent RN or PN for a single nonmetastatic renal tumor between 1997 and 2014 at our institution were identified. Exclusion criteria were venous tumor thrombus and preoperative eGFR <15 ml/min/1.73 m2.

Intervention

RN and PN.

Outcome measurements and statistical analysis

Hierarchical generalized linear mixed-effect models with backward selection of candidate preoperative features were used to predict long-term eGFR following RN and PN, separately. Predictive ability was summarized using marginal RGLMM2, which ranges from 0 to 1, with higher values indicating increased predictive ability.

Results and limitations

The analysis included 1152 patients (13 206 eGFR observations) who underwent RN and 1920 patients (18 652 eGFR observations) who underwent PN, with mean preoperative eGFRs of 66 ml/min/1.73 m2 (standard deviation [SD] = 18) and 72 ml/min/1.73 m2 (SD = 20), respectively. The model to predict eGFR after RN included age, diabetes, preoperative eGFR, preoperative proteinuria, tumor size, time from surgery, and an interaction between time from surgery and age (marginal RGLMM2=0.41). The model to predict eGFR after PN included age, presence of a solitary kidney, diabetes, hypertension, preoperative eGFR, preoperative proteinuria, surgical approach, time from surgery, and interaction terms between time from surgery and age, diabetes, preoperative eGFR, and preoperative proteinuria (marginal RGLMM2). Limitations include the lack of data on renal tumor complexity and the single-center design; generalizability needs to be confirmed in external cohorts.

Conclusions

We developed preoperative tools to predict renal function outcomes following RN and PN. Pending validation, these tools should be helpful for patient counseling and clinical decision-making.

Patient summary

We developed models to predict kidney function outcomes after partial and radical nephrectomy based on preoperative features. This should help clinicians during patient counseling and decision-making in the management of kidney tumors.  相似文献   
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