带种植体骨磨片制作方法的改进

目的:对原有手工磨片的制作方法进行改进,以便更广泛地满足人工种植牙的临床与实验研究。方法:对浸润剂、包埋剂的配比进行改良,同时对粘贴剂、磨片步骤、染色方法进行调整,以达到制作更高水平种植体磨片的要求。结果:与原有方法比较,采用改进后的方法制作磨片,所磨制的磨片表面更加平整,厚度更加均匀,染色脱片率大为下降。同时根据观察骨与种植体的结合、正畸治疗中加种植支抗后骨组织受力的分析等不同实验要求,通过采用相应的染色方法,均达到满意的结果。结论:改进后的手工磨片法制作人工种植牙骨磨片,不仅可以提高磨片的质量和成功率,同时也能满足临床与实验的不同要求。     

Fine-needle aspiration biopsy of metaplastic carcinoma of the breast: Report of a case with abundant myxoid ground substance

Metaplastic carcinoma (MC) is an uncommon neoplasm of the breast. There are several variants of MC depending on the dominant histologic pattern. The components include overt infiltrating ductal carcinoma, extensive squamous differentiation and spindle cell proliferation with or without chondroid or osseous heterologous elements. In FNA smears, only 57% of cases show both ductal carcinoma and metaplastic component. Thus, in almost one half of the cases, the diagnosis is not possible by FNA. Often it is difficult to define the epithelial or sarcomatous character of malignant cells. We describe a case of metaplastic carcinoma of the breast studied by fine-needle aspiration cytology in which myxoid ground substance was the dominant feature in the cytology smears. The rest of the material was composed of scanty isolated atypical cells with large and irregular nuclei. It is important to bear in mind the diagnosis of MC and make a careful search for atypical cells when the cytological smears are mainly composed of myxoid ground substance. Diagn Cytopathol 1996;14:325–327. © 1996 Wiley-Liss, Inc.     

Changes in activity of neutral proteases in tissues of ground squirrels in the dynamics of hibernation

Total activities of neutral proteases in the cerebral, hepatic, and myocardial tissues of ground squirrel vary during hibernation: in autumn (before hibernation) activities of the enzymes in the brain and myocardium start increasing, while in the liver they do not change. A common feature for all tissues is minimum activity of active neutral proteases in the middle of hibernation month 1 bout, while the maximum activity is recorded before awakening. Translated from Byulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 146, No. 9, pp. 278–280, September, 2008     

Neuromuscular adaptations in older males and females with knee osteoarthritis during weight-bearing force control

Background

Females exhibit significantly greater incidence, prevalence, and severity of osteoarthritis (OA) compared to males. Despite known biological, morphological, and functional differences between males and females, there has been little sex-related investigation into sex-specific biomechanical and neuromuscular responses to OA.

城市无障碍设施(盲道)应用状况的调查及分析

文题释义： 无障碍设施：以提高残障人士的社会生活质量,确保有需求的人能够安全地、方便地使用为目的的各种设施。 盲道：在人行道上或其他场所铺设的一种固定形态的地面砖,视障者可产生盲杖触觉及脚感,引导视障者前行和辨别方向的通道。 背景：国内城市无障碍设施不完善,但是视障者对无障碍设施的需求较为急迫。 目的：通过调研石家庄城市无障碍设施(以盲道为例)的应用状况,以了解民众对于城市无障碍设施的认知、存在问题,并提出针对性改善建议。 方法：以问卷调查方式,在河北省石家庄市随机抽选118名普通市民和51名环卫工人,进行盲道认知情况调查,同时对60名视障者进行盲道使用情况调查。 结果与结论：多数市民、环卫工人和视障者对盲道有一定了解,但民众对盲道的知晓率依然较低,仍有7%的普通市民和18%的环卫工人对盲道完全不了解;视障者出行率极低,仅38%的视障者可经常出行;50%以上市民和视障者认为盲道没有起到实际作用,仅19%的市民对盲道的监管、维护、保养工作较满意率,56%的视障者认为盲道没有实际作用,42%的视障者表示其出行范围多以家为中在1 km以内。提示民众知晓率低、盲道利用率低,建议从加强宣传与培训、对视障者行康复训练、加强建设与维护三方面着手,才能更好地保障残疾人生存权益,促进其回归社会,提高其生活质量。 ORCID: 0000-0002-3784-3867(苟波) 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程     

胸膜凹陷征在磨玻璃密度结节诊断中的价值及病理基础

目的 探讨胸膜凹陷征(PI)在磨玻璃密度结节(GGN)诊断中的价值及病理基础.方法 收集经手术病理证实的GGN83例,分析CT图像PI的情况,并与手术及病理进行对照研究.结果 原位腺癌(AIS)组无PI,微浸润腺癌(MIA)组PI发生率约55.55％,浸润性腺癌(IAC)组PI发生率约75.86％,同时PI组GGN中可见肿瘤相关成纤维细胞.结论 MSCT下PI在GGN的诊断与鉴别诊断中有重要价值,而肿瘤相关成纤维细胞为主要间质细胞基础.     

Effects of childhood trauma on HPA-axis reactivity in women free of lifetime psychopathology

Exposure to childhood trauma may induce persistent changes in Hypothalamic-Pituitary-Adrenal (HPA)-axis functioning even in the absence of current psychopathology. Because previous studies did not systematically exclude subjects with lifetime psychiatric morbidity, prevalent psychopathology may have confounded the association. In this study we investigated whether women exposed to childhood trauma, but without a history of psychiatric disorders, show alterations in HPA-axis functioning. We included 10 women exposed to significant childhood trauma and 12 non-exposed women. All women were between 29 and 64 years old, mentally and physically healthy, and without current or lifetime psychopathology. HPA-axis functioning was assessed as 1) basal activity with salivary cortisol patterns over 8 time points on two consecutive sampling days and 2) plasma cortisol and adrenocorticotropic hormone (ACTH) reactivity over 7 time points after the combined dexamethasone/corticotropin-releasing hormone (dex/CRH) challenge test. Basal salivary cortisol output did not differ between trauma-exposed compared to non-exposed women. Significantly blunted plasma cortisol and ACTH responses in response to dex/CRH administration were found in the trauma-exposed compared to the non-exposed women (F(1,20) = 5.08, p = 0.04 and F(1,20) = 5.23, p = 0.03 respectively). Adjusting for age, body mass index (BMI), oral contraceptive use, and menopausal status, somewhat weakened the associations for cortisol as well as ACTH (F(1,16) = 3.30, p = 0.09) and F(1,16) = 2.17, p = 0.16 respectively), but for cortisol absolute differences in point estimates were largely unaffected. Although basal cortisol patterns were similar in the two groups, exposure to childhood trauma seemed to be related to a blunted HPA-axis reactivity in women who were free of current or lifetime psychopathology.     

Gait asymmetries are exacerbated at faster walking speeds in individuals with acute anterior cruciate ligament reconstruction

Previous research suggests more biomechanically demanding tasks (e.g., stair descent, hopping) magnify biomechanical asymmetries compared with walking after anterior cruciate ligament (ACL) reconstruction. However, it is unclear if modifying task-specific constraints, like walking speed also elicits greater biomechanical asymmetries in this population. We examined the effects of manipulating walking speed on ground reaction force (GRF) asymmetries in individuals with ACL reconstruction and uninjured controls. Thirty individuals with ACL reconstruction (age = 20.6 ± 5.4 years, body mass index [BMI] = 23.9 ± 3.3 kg/m²) and 15 controls (age = 23.1 ± 4.5 years, BMI = 23.6 ± 2.7 kg/m²) were tested on an instrumented treadmill at three speeds (100%, 120%, and 80% self-selected speed). Bilateral vertical and posterior-anterior GRFs were recorded at each speed. GRF asymmetries were calculated by subtracting the uninjured from the injured limb at each percent of stance. Statistical parametric mapping was used to evaluate the effects of speed on GRF asymmetries across stance. We found vertical and posterior GRF asymmetries were exacerbated at faster speeds and reduced at slower speeds in ACL individuals but not controls (p < .05). No differences in anterior GRF asymmetries were observed between speeds in either group (p > .05). Our results suggest increasing walking speed magnifies GRF asymmetries in individuals with ACL reconstruction. Statement of Clinical Significance: Evaluating both preferred and fast walking speeds may aid in characterizing biomechanical asymmetries in individuals with ACL reconstruction which may be valuable in earlier rehabilitative time points when more difficult tasks like hopping and running are not feasible.     

Coronavirus Disease 2019 (COVID-19) CT Findings: A Systematic Review and Meta-analysis

PurposeTo date, considerable knowledge gaps remain regarding the chest CT imaging features of coronavirus disease 2019 (COVID-19). We performed a systematic review and meta-analysis of results from published studies to date to provide a summary of evidence on detection of COVID-19 by chest CT and the expected CT imaging manifestations.MethodsStudies were identified by searching PubMed database for articles published between December 2019 and February 2020. Pooled CT positive rate of COVID-19 and pooled incidence of CT imaging findings were estimated using a random-effect model.ResultsA total of 13 studies met inclusion criteria. The pooled positive rate of the CT imaging was 89.76% and 90.35% when only including thin-section chest CT. Typical CT signs were ground glass opacities (83.31%), ground glass opacities with mixed consolidation (58.42%), adjacent pleura thickening (52.46%), interlobular septal thickening (48.46%), and air bronchograms (46.46%). Other CT signs included crazy paving pattern (14.81%), pleural effusion (5.88%), bronchiectasis (5.42%), pericardial effusion (4.55%), and lymphadenopathy (3.38%). The most anatomic distributions were bilateral lung infection (78.2%) and peripheral distribution (76.95%). The incidences were highest in the right lower lobe (87.21%), left lower lobe (81.41%), and bilateral lower lobes (65.22%). The right upper lobe (65.22%), right middle lobe (54.95%), and left upper lobe (69.43%) were also commonly involved. The incidence of bilateral upper lobes was 60.87%. A considerable proportion of patients had three or more lobes involved (70.81%).ConclusionsThe detection of COVID-19 chest CT imaging is very high among symptomatic individuals at high risk, especially using thin-section chest CT. The most common CT features in patients affected by COVID-19 included ground glass opacities and consolidation involving the bilateral lungs in a peripheral distribution.