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排序方式: 共有9426条查询结果,搜索用时 31 毫秒
991.
Iris Schulz Peter M. Schneider Klaus Olek Markus A. Rothschild Michael Tsokos 《Forensic science, medicine, and pathology》2006,2(2):95-101
Postmortem animal interference may be confused at first sight with injuries of vital origin, thus arousing suspicion of external
violence preceding death. A reliable classification of the origin of such doubtful injuries is of crucial importance, a fact
that is especially true for the investigation of suspected homicide and/or mammade body mutilation after death. In forensic
pathology, the identification of injuries as caused by animals postmortem and the classification of a particular species as
responsible for a specific injury pattern under question is usually done by forensic pathologists with vast practical experience
and special knowledge of the appearance and morphology of tooth marks of carnivores and rodents, respectively. However, a
molecular biological investigation of such wounds could provide genetic evidence that an injury pattern present on a corpse
was truly caused postmortem by animal interference and thus support the pathologist's expertise. For this purpose, we developed
a panel of small species-specific short-tandem repeat systems (<150 bp) for animals typically involved in postmortem scavenging
of human remains, such as dogs and cats as well as wild-living rodents (mice and rats) having possible access to death scenes
inside apartments or buildings. A specific and sensitive cross-species multiplex polymerase chain reaction was then established
including the species-specific animal markers, thus enabling the genetic identification of wounds caused postmortem by different
animals on human remains.
This study was presented at the Sixth International Symposium in Advanced Legal Medicine (ISLAM), Hamburg, Germany, September
2006. 相似文献
992.
目的 为南五味子药材的鉴定提供依据。方法 用性状鉴别、扫描电镜和薄层色谱方法对不同产地华中五味子及其近缘种绿叶五味子、翼梗五味子和红花五味子果实进行生药性状、种子表面微形态和薄层鉴别。结果 依据种皮表面的微形态特征可以将华中五味子、红花五味子、绿叶五味子及翼梗五味子分为3个类型。去氧五味子素(五味子甲素)(deoxyschisandrin)、五味子酯甲(schisantherin A)的薄层定性表明产于陕西平利、河南栾川、山西阳城、湖南衡山的华中五味子、绿叶五味子和红花五味子果实中都含有五味子酯甲和五味子甲素;翼梗五味子果实中仅含有五味子酯甲,而甘肃小陇山、陕西留坝产华中五味子果实中检测不到这两种成分。结论 不同产地华中五味子、红花五味子、绿叶五味子及翼梗五味子的干燥果实可以依据种皮表面的微形态特征和薄层色谱结果加以鉴别。 相似文献
993.
The quasistatic and dynamic pressure volume characteristics of the lungs were measured in five anesthetized, paralyzed open-chest
rats. Psuedo-random volume perturbations over a frequency range of 0.25 to 25 Hz and having peak-peak amplitudes of 1 to 4
ml were applied after the lungs were allowed to expire against 0.2, 0.4, 0.6, and 0.8 kPa positive endexpiratory pressure
(PEEP). The lung mechanics were partitioned in two ways: a linear dynamic block followed by a static nonlinearity (Wiener
model) and a static nonlinearity ahead of a linear dynamic block (Hammerstein model). It was found that a Hammerstein model
featuring a third-order polynomial static nonlinearity and a linear impulse response function of 1-sec duration accounted
for the greatest amount of the output variance (98.8±06%, mean±SD from perturbations of 4 ml amplitude and PEEP-0.8 kPa).
The static nonlinear behavior matched the measured quasistantic pressure volume behavior obtained at the same amplitude and
at the same level of PEEP, provided that all direct current gain of the model was located within the static nonlinearity.
Under these conditions, the linear resistance was inversely dependent on the PEEP, whereas little PEEP or amplitude dependence
of the linear compartment elastance was observed. Thus, of the two block-structured models tested, the Hammerstein model accounted
better for the large amplitude nonlinear mechanical behavior. However, neither model could account for the dependence of the
linear block resistance on PEEP. 相似文献
994.
藏药如意珍宝丸的鉴别和含量测定 总被引:4,自引:2,他引:2
目的 建立藏药如意珍宝丸的鉴别和含量测定方法。方法 采用薄层色谱法和高效液相色谱法。结果 如意珍宝丸中 ,在荜茇、红花、肉桂、黄葵子、丁香和决明子等药材与对照药材相应的色谱位置处各有相同的斑点 ;并采用HPLC法测定了制剂中诃子的有效成份没食子酸的含量 ,其回归方程为A =6× 10 5C +718 14 (r =0 9998) ,RSD =1 5 8%。结论 所建立的鉴别与含量测定方法简便、准确 ,可用于如意珍宝丸的质量控制。 相似文献
995.
脊柱孤立性浆细胞瘤的临床及影像学特点分析 总被引:4,自引:0,他引:4
目的:探讨脊柱孤立性浆细胞瘤的临床及影像学特点。方法:分析经手术病理检查证实的6例脊柱孤立性浆细胞瘤病例的临床特点及影像学特征。结果:病椎附近逐渐加重的疼痛是其共同首发临床表现。其X线片多表现为椎体的溶骨性破坏;ECT上表现不一;CT多为椎体骨质的虫嗜状破坏;MRI示病椎信号失均,T1WI低信号,T2WI等或稍高信号,增强扫描有不均匀强化。结论:CT及MRI可明确脊柱孤立性浆细胞瘤的形态特征及病灶范围,其确诊仍需借助骨髓活检或手术标本病理检查。但对颈背部疼痛的患者,早期行MRI检查有助于及时发现病变,避免严重脊柱脊髓损害的出现。 相似文献
996.
从多孢木霉(Trichoderma polysporum)的发酵液中,分离到一组具有免疫抑制作用的物质-G-18-Ⅰ、G-18-Ⅱ、G-18-Ⅲ、G-18-Ⅳ,其中G-18-Ⅳ为在红外光谱2100cm~(-1)具有强吸收的异腈类化合物,基于理化性质及光谱数据,已鉴别G-18-Ⅳ为异腈素酸E(木菌素)甲酯。 相似文献
997.
心率与血压变异性的多变量、多维信号分析进展 总被引:9,自引:2,他引:7
心率变异性与血压变异性反映心血管系统自主神经的调制活动,近年研究已向多变量、多维、动态分析方向发展。心率与血压变异性的多变量系统辨识、时频分析及非线性动力学分析等技术方法,将在心血管疾病的危险性预报、病情评估、疗效评价及特种环境医学等领域有更多应用。 相似文献
998.
Sara Assecondi A.M. Bianchi H. Hallez S. Staelens S. Casarotto I. Lemahieu G.A. Chiarenza 《Clinical neurophysiology》2009,120(10):1819-1827
ObjectiveThis article proposes a method to automatically identify and label event-related potential (ERP) components with high accuracy and precision.MethodsWe present a framework, referred to as peak-picking Dynamic Time Warping (ppDTW), where a priori knowledge about the ERPs under investigation is used to define a reference signal. We developed a combination of peak-picking and Dynamic Time Warping (DTW) that makes the temporal intervals for peak-picking adaptive on the basis of the morphology of the data. We tested the procedure on experimental data recorded from a control group and from children diagnosed with developmental dyslexia.ResultsWe compared our results with the traditional peak-picking. We demonstrated that our method achieves better performance than peak-picking, with an overall precision, recall and F-score of 93%, 86% and 89%, respectively, versus 93%, 80% and 85% achieved by peak-picking.ConclusionWe showed that our hybrid method outperforms peak-picking, when dealing with data involving several peaks of interest.SignificanceThe proposed method can reliably identify and label ERP components in challenging event-related recordings, thus assisting the clinician in an objective assessment of amplitudes and latencies of peaks of clinical interest. 相似文献
999.
1000.
Helen M. Robinshaw 《Early child development and care》1996,120(1):67-93
This article reports a longitudinal study of the communicative and linguistic development of five infants, identified as having severe or profound bilateral sensorineural hearing loss, and using amplification consistently, by 3-6 months of age. Each hearing impaired infant was carefully matched for chronolgical age, social and cultural background with a normally hearing infant. The parents of each of the infants had normal hearing and spoken English was the first language of the home. Video recorded social interaction took place over a variety of semi-structured contexts and occurred at six-weekly intervals from 6 to 21 months. The pattern of gestural and vocal communication and the transition to symbolic language by each hearing impaired and hearing infant forms the focus of this report. It is concluded that severely and profoundly hearing impaired infants can follow a normal pattern of communicative and linguistic development (albeit sometimes delayed) when hearing impairment is identified within the first months of life and appropriate interventions are in place. 相似文献