基于敏感性定理的EIT重构算法仿真研究

为了研究性能更好的EIT图像重构算法，我们对基于敏感性定理的EIT图像重构算法进行了计算机仿真研究，并与几种常用图像重构算法进行比较，提出对基于敏感性定理的EIT图像重构算法的改进措施。     

抗生素应用与烧伤创面细菌药敏变迁

目的：了解烧伤创面菌种及其耐药性变迁与抗生素应用的关系。指导抗生素选择。方法：采集1992－2000年烧伤住院病人分泌物细菌培养加药敏试验,对1992－1994年、1995－1997年（抗生素更替期）、1998－2000年（三代头孢广泛应用期）三个阶段的菌种及药敏分析比较。结果：金葡菌检出率相对稳定,位居前列,对万古霉素保持100％敏感率。绿脓杆菌检出率在第二阶段下降到第6位,第三阶段又上升到第3倍,对常用抗生素的敏感率逐年下降。大肠杆菌、肠球菌为常见菌种,阴沟杆菌检出率逐年增高。结论：抗生素的更换影响烧伤创面菌种类型和比例,广泛长期使用三代头孢和喹喹酮类抗生素,使细菌耐率逐年上升,金葡萄、绿脓杆菌仍然是烧伤创面的主要菌种。     

Can supplementary contrast-enhanced MRI of the breast avoid needle biopsies in suspicious microcalcifications seen on mammography? A systematic review and meta-analysis

PurposeTo analyze the rate of potentially avoidable needle biopsies in mammographically suspicious calcifications if supplementary Contrast-Enhanced MRI (CE-MRI) is negative.MethodsUsing predefined criteria, a systematic review was performed. Studies investigating the use of supplemental CE-MRI in the setting of mammographically suspicious calcifications undergoing stereotactic biopsy and published between 2000 and 2020 were eligible. Two reviewers extracted study characteristics and true positives (TP), false positives, true negatives and false negatives (FN). Specificity, in this setting equaling the number of avoidable biopsies and FN rates were calculated. The maximum pre-test probability at which post-test probabilities of a negative CE-MRI met with BI-RADS benchmarks was determined by a Fagan nomogram. Random-effects models, I²-statistics, Deek’s funnel plot testing and meta-regression were employed. P-values <0.05 were considered significant.ResultsThirteen studies investigating 1414 lesions with a cancer prevalence of 43.6% (range: 22.7–66.9%) were included. No publication bias was found (P = 0.91). CE-MRI performed better in pure microcalcification studies compared to those also including associate findings (P < 0.001). In the first group, the pooled rate of avoidable biopsies was 80.6% (95%-CI: 64.6–90.5%) while the overall and invasive cancer FN rates were 3.7% (95%-CI: 1.2–6.2%) and 1.6% (95%-CI 0–3.6%), respectively. Up to a pre-test probability of 22%, the post-test probability did not exceed 2%.ConclusionA negative supplementary CE-MRI could potentially avoid 80.6% of unnecessary stereotactic biopsies in BI-RADS 4 microcalcifications at a cost of 3.7% missed breast cancers, 1.6% invasive. BI-RADS benchmarks for downgrading mammographic calcifications would be met up to a pretest probability of 22%.     

83例住院患者念珠菌感染的菌株鉴定及药敏分析

目的 :探讨住院患者念珠菌感染的种类及耐药现状。方法 :用法国生物 -梅里埃公司酵母菌鉴定系统和药敏试纸条进行菌株鉴定和药敏试验。结果 :白色念珠菌检出率最高 (5 0 .6 0 % ) ,热带念珠菌次之 (2 6 .5 1% ) ,高里氏念珠菌、近平滑念珠菌、分别为 9.6 4%和 7.2 3% ,其它念珠菌均在 5 .0 %以下。 6种抗真菌药中 ,5 -氟胞嘧啶、两性霉素B、制霉菌素的耐药率最低 (1.2 0 % ) ,唑类抗真菌的耐药率最高 (8.43～ 18.0 7% )。结论 :结果提示临床医师治疗真菌感染时应先进行培养和药敏试验 ,以便合理治疗 ,预防医院内感染。     

凝固酶阴性葡萄球菌医院感染的研究

目的 :防治凝固酶阴性葡萄球菌医院内感染。方法 :用经典生理生化鉴定方法 ,对各种临床标本分离到的96株凝固酶阴性葡萄球菌 (CNS)进行种的鉴定、药敏试验和葡萄球菌粘质的检测。结果 :分离到 7种CNS ,其中表皮葡萄球菌占 5 5 .2 % ,溶血葡萄球菌占 2 9.2 %。青霉素耐药率为 6 9.8% ,甲氧西林耐药凝固酶阴性葡萄球菌占CNS的5 8.3 % ,产葡萄球菌粘质菌株占 84.4%。结论 :临床感染CNS中表皮葡萄球菌和溶血葡萄球菌占绝大多数。CNS对多种抗生素耐药 ,治疗其感染应以药敏结果为依据。可选用万古霉素、利福平、丁胺卡那霉素、环丙沙星等药物治疗。     

Classification of heart failure in population based research: An assessment of six heart failure scores

Several scores based on symptoms and signs have been developed to assess the presence of heart failure. The goal of this study was to compare six heart failure scores in non-hospitalised subjects and to determine their usefulness in population based research. The scores were applied to 54 participants of a population based study. All underwent a complete medical examination, including chest X-ray, electrocardiography and Doppler echocardiography. Using all information available, a cardiologist, unaware of the results of the scores, clinically classified participants as having no, possible or definite heart failure. Sensitivity, specificity, predictive values and receiver operating characteristics were calculated, using the cardiologist's assessment as a gold standard. The cardiologist judged definite or possible heart failure to be present in 17 persons. All scores had a high sensitivity for the detection of definite heart failure, whereas the study of men born in 1913 and Walma's score had the highest sensitivity for the combination of possible and definite heart failure. Gheorgiade's and the Boston score had the highest positive predictive values. In conclusion, five of the six scores we studied are broadly similar in the detection of heart failure. The men born in 1913 score relies heavily on the assessment of dyspnea, resulting in a relatively large number of false positives. Although the scores are useful in detecting manifest heart failure, objective measurements of cardiac function appear necessary to reduce the false positive rate and accurately detect early stages of heart failure.     

Validation of the STR system FES/FPS for forensic purposes in an Austrian population sample

The short tandem repeat system FES/FPS was amplified by the polymerase chain reaction (PCR) in 211 unrelated Austrians and analysed by horizontal, non-denaturing electrophoresis. The allele distribution was in Hardy-Weinberg equilibrium. No mutations were found in 25 families (50 meioses). The mean exclusion chance was 0.49, the discriminating power 0.86 and the heterozygosity rate 74.4%. Amplification could be achieved with as little as 100 pg of high molecular weight DNA, which could be reduced to 75 pg by using 32 instead of 30 cycles. By reamplifying 1 l for another 15 cycles, the threshold could be reduced to less than 20 pg. In a degradation experiment DNA extracted from bloodstains stored for up to 24 days in a moist chamber and DNA boiled for up to 18 min could be amplified.     

结核免疫水平监测方法的对比研究

目的　进一步证实 Ｐ Ｐ Ｄ 实验在监测结核免疫力中的应用价值。方法　用卡介苗接种８７９名儿童,１２ 周后进行 Ｐ Ｐ Ｄ 试验并查验卡痕反应,计算评价筛选试验的指标。结果　卡痕试验的敏感度、特异度、正确指数均低,而误诊率、漏诊率均高。结论　 Ｐ Ｐ Ｄ 实验是目前尚未开展人体内测定结核免疫力前唯一有效的监测结核免疫力的方法。     

Modulation of sodium currents in rat CA1 neurons by carbamazepine and valproate after kindling epileptogenesis

PURPOSE: To determine the modulation of sodium currents in hippocampal CA1 neurons by carbamazepine (CBZ) and valproate (VPA), before and after kindling epileptogenesis. METHODS: Voltage-dependent sodium current was measured in isolated hippocampal CA1 neurons, by using the whole-cell voltage-clamp technique. CBZ (15-100 microM) or VPA (0.5-5 mM) was applied by bath perfusion. Cells from fully kindled rats were compared with controls, 1 day and 5 weeks after the tenth generalized seizure. RESULTS: CBZ did not affect sodium current activation but selectively shifted the voltage dependence of steady-state inactivation to more hyperpolarized potentials. One day after the last kindled generalized seizure, the shift induced by 15 microM CBZ was 2.1+/-0.5 mV (mean +/- SEM; n = 20) compared with 4.3+/-0.3 mV (n = 16; p<0.001) in matched controls. The EC50 of the concentration-effect relation was 57+/-6 microM compared with 34+/-2 microM (p<0.01) in controls. Five weeks after kindling, these values had recovered to a level not different from control. VPA induces at a relatively high concentration a similar but smaller shift in voltage dependence of inactivation than does CBZ. After kindling, the shift induced by 2 mM VPA (2.8+/-0.6 mV; n = 19) was not different from controls (3.0+/-0.5 mV; n = 22). The EC50 for VPA was 2.6+/-0.3 mM compared with 2.5+/-0.4 mM in controls. CONCLUSIONS: Both CBZ and VPA selectively modulate the voltage dependence of sodium current steady-state inactivation and as a consequence reduce cellular excitability. The effect of CBZ was reduced immediately after kindling epileptogenesis, apparently by a reduced affinity of its receptor. In contrast, the shift induced by VPA was not different at any stage after kindling epileptogenesis. The change in CBZ sensitivity after kindling is related to epileptic activity rather than to the epileptic state, because it almost completely recovers in a period without seizures.     

Befindlichkeitsstörungen ohne Befund—moderne Syndrome

Zusammenfassung Befindlichkeitsstörungen ohne pathologischen Befund stellen einen nicht unerheblichen Anteil des internen Krankengutes dar. Ein zunehmender Teil der Patienten führt diese Beschwerden auf Einflüsse aus dem Bereich der Arbeitswelt oder Umwelt zurück. Mangels vorliegender Pathologie neigt die Schulmedizin dazu, diese Syndrome eher dem psychiatrischen Formenkreis zuzuordnen oder psychologische Konzepte in die Kausalitätsüberlegungen einzubeziehen. Medien wie Alternativmedizin unterstützen in diesem Themenbereich meist nicht die Konzepte der faktenorientierten Schulmedizin, sie halten Organschäden durch Belastungen mit Umweltnoxen für durchaus möglich, selbst wenn diese in zulässiger Höhe liegen. Postuliert wird häufig eine gesteigerte Individualempfindlichkeit. Beispiele solcher modern interpretierter Syndrome sind das Sick Building Syndrome, das chronische Erschöpfungssyndrom oder die idiopathische Umweltunverträglichkeit. Infolge der Unspezifität dieser Beschwerden ähnelt sich die Symptomatik, wenngleich diesen Syndromen durchaus unterschiedliche Konzepte zugrunde gelegt werden. Deshalb ist die Überlegung, es handle sich immer um das selbe Krankheitsbild, unberechtigt. Eine breite differenzialdiagnostische Palette ist gefordert, da es sich meist um Ausschlussdiagnosen handelt. Zur realitätsnahen Beurteilung sind fallweise auch Verfahren des Biomonitorings oder Ambientmonitorings heranzuziehen.

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