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11.
《The Knee》2022
BackgroundPatients with knee joint pathology present with variable muscular responses across the muscles of the lower limb and pelvis. Conventional approaches to characterizing muscle function are limited to gross strength assessments that may overlook subtle changes both in the thigh, hip and shank musculature.PurposeTo describe individualized patterns of lower extremity muscle volumes in patients with knee pathologies.MethodsThis was a retrospective case series performed in a University medical center. Nine patients diagnosed with meniscus tear recommended to undergo meniscectomy volunteered. Participants underwent 3.0 Tesla magnetic resonance imaging (MRI) of the lower extremities. Thirty-five MRI-derived muscle volumes were compared between limbs and expressed as percentage asymmetry. For additional context, z-scores were also calculated for mass- and height-normalized muscles and pre-determined muscle groupings relative to a normative database.ResultsThere were no consistent patterns observed when considering between-limb asymmetries among all patients. The ankle musculature (dorsiflexors, plantar flexors, and invertors) was the only muscle group to be consistently smaller than normal for all patients, with the psoas major and flexor hallucis longus being the only individual muscles. The severity or chronicity of injury and presence of surgical intervention did not appear to have a clear effect on muscle volumes.ConclusionPatients with a history of meniscal pathology demonstrate inconsistent patterns of lower extremity muscle volumes about the hip, knee, and ankle between limbs and in comparison to uninjured individuals. These data support the need for individualized assessment and intervention in this population. 相似文献
12.
戊型肝炎病毒归科的形态学证据 总被引:2,自引:0,他引:2
采用超簿切片制样及负染色免疫电镜方法,对经细胞培养自戊型肝炎病人分离的87A株病毒进行了形态及形态发生的研究。结果显示,感染细胞胞浆局灶性空泡液泡病变区明显而普遍;病毒呈晶格样排列,在胞浆内装配成熟,与粗面内质网、病毒性包涵体、微丝等密切相关;病毒毒粒无囊膜,大小约30nm呈圆形,表面形态不规整,电致密度不均一,偶见“凹杯形”、“刺突”等表面超微结构;感染细胞核呈现扭曲变形,异染色质趋边等显著受累及病变。其形态及形态发生特征表明其应为嵌杯病毒科新属—嗜肝RNA病毒属的成员,而部分核苷酸序列分析也支持其为戊型肝炎病毒。 相似文献
13.
G. Paraskevas B. Papaziogas C. Lazaridis P. Gigis T. Papaziogas 《Surgical and radiologic anatomy : SRA》2002,23(6):437-442
Abstract: Three cases (two male, one female) of annular pancreas are presented, which were found and operated on within the last three decades. Diagnosis was made using imaging techniques, especially ultrasonography and computed tomography. In two cases there was incomplete obstruction, while in the other obstruction was complete. It is characteristic that in the case of complete obstruction the annular portion of the pancreas attached to a circular band of connective tissue, while in the two cases of incomplete obstruction there was a complete ring of pancreatic tissue. In all cases surgical intervention was needed in order to create a bypass. In the first case gastroenterostomy and truncal vagotomy was performed, in the second latero-lateral duodeno-jejunostomy and in the third latero-lateral antropyloroduodeno-jejunostomy. The embryology and morphology of the annular pancreas, the morphology of its duct system, diagnosis, differential diagnosis and the surgical treatment of this rare condition are reviewed. 相似文献
14.
D. J. P. Ferguson A. A. McColm D. M. Ryan P. Acred 《Virchows Archiv : an international journal of pathology》1986,410(1):43-48
Summary The initial colonization, byStaphylococcus aureus, of the catheter damaged aortic valve and aorta of the rabbit, was examined by light and electron microscopy at 15 min, 3 h and 24 h post inoculation (PI). At 15 min PI, the majority of bacteria (80%) were located on the lateral surfaces of the thrombic vegetations while 20% were attached directly to the connective tissue of the aortic valve and aorta in areas where the endothelial lining was disrupted. By 3 h the bacteria on the thrombic vegetations were covered by fibrin. At this time, the bacteria both within the vegetations and on the surface of the vasculature were undergoing multiplication to form small groups. The precipitation of thrombus around the bacteria attached to the surface of the aorta to form microscopic infected vegetations had occurred by 24 h PI. The colonizing bacteria did not elicit any phagocytic response. The colonization of the cardiovasculature byStaph. aureus did not necessarily require pre-existing vegetations. 相似文献
15.
Barth TF Leithäuser F Döhner H Bentz M Pawlita M Schmid U Möller P 《Virchows Archiv : an international journal of pathology》2000,436(4):357-364
In contrast to primary gastric lymphomas of B-cell type, little is known about primary gastric T-cell lymphomas. We describe
three cases with remarkably similar features: diffuse growth, epitheliotropism, medium too large cell size, high apoptotic
rates, and a CD3+, CD4+, CD8+, CD45RO+ immunophenotype. Clonal TCRγ gene rearrangement was shown in two cases. Epstein-Barr
virus infection was excluded in two cases. Taking advantage of fresh-frozen material, we analyzed two cases further, revealing
CD5–, CD16+, CD56–, CD57–, CD25+, CD30+, CD103 (αEβ7)+, bcl-2 protein+, CD95+, CD95 ligand(L)–. CD95L, however, was detected
in histiocytic and fibroblastoid by stander cells. The lymphomas expressed granzyme B, perforin, and the TIA-1 antigen in
various combinations. All three cases had a very unfavorable clinical course characterized by local recurrence and/or dissemination
to other epithelial sites, leading to death within 6–12 months after the initial diagnosis despite surgery and aggressive
antineoplastic treatment. These data suggest a novel variant of peripheral T-cell lymphoma operationally characterized as
primary gastric, apoptosis-rich, CD103+, EBV-, T-cell lymphoma co-expressing CD4, CD8, CD16 and cytotoxic molecules.
Received: 20 August 1999 / Accepted: 2 November 1999 相似文献
16.
The pedicle screw and hook have become popular instruments in treating spinal deformity and disease. This study gathered morphological data on thoracic and lumbar spines in a Japanese population that should serve as useful reference for posterior instrumentation surgery. One hundred and three dry bones were used to investigate the morphology of pedicle and facet in thoracic and lumbar spines. Measurements included the diameter and axial length of pedicle from T8 to L5, height and width of facets and thickness of articular processes from T1 to T12, and axial angle of pedicle from T1 to L5. The diameter and axial length of pedicle were smallest at T8, diameter was largest at L5 and axial length was largest at L3. Height of facets and thickness of articular processes were largest at T12. Men tended to have larger pedicles and facets than women. Transverse angle of pedicle was smallest at T12. These precise data may provide useful information when performing posterior instrumentation surgery and when developing new spinal implant systems for Asians. 相似文献
17.
18.
Wähle P. Meyer G. Albus K. 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1986,61(2):364-374
Summary Using a polyclonal antiserum against neuropeptide Y (NPY; J.M. Allen et al. 1983a) immunohistochemistry was carried out using the PAP method. Neurones displaying NPY-like immunoreactivity are seen mainly in cortical layers V/ VI, adjacent white matter and corona radiata. Only few neurones occur in superficial layers II/III. Neurones are multipolar to bitufted with spineless dendrites; somata are either round (layers V, II/III) or spindle-like (layer VI, white matter) with diameters between 16 and 20 m. Axones were identified by their initial smoother profiles, which are smaller in diameter than principal dendrites, by their typical branching pattern and the occurrence of terminal portions. It was found, that the degree of axonal ramification in proximal parts of axones is rather poor. Most NPY-neurones seem to project intracortically or even locally, except neurones in layers VI and the white matter. The latter neurones have ascending axonal branches terminating in layer VI and V, thus contributing to the dense NPY-plexus in these layers, whereas some layer VI neurones have axonal branches descending into the white matter. The axonal plexus in upper cortical layers is most probably fed by the ascending axones of layer V neurones, passing layer IVc in a strictly vertical direction. Fine smooth fibers of unknown origin which ascend from the white matter in a vertical direction through the grey matter also contribute to the plexus in layer II/III. In semithin sectioned material three terminal types were identified. Firstly, en passant boutons on immunnegative pyramidal neurones, secondly, perisomatically arranged, basket-like terminals, bending around unstained non-pyramidal neurones, and thirdly, about 60 m long vertically oriented rows of boutons exclusively on apical dendrites of layer II/III pyramidal neurones. Due to the unconspicious axonal pattern and the frequently observed basket-like terminal form, we conclude that most NPY-ir neurones can be regarded as a class of unspecific local field basket cells; the origin of the vertically arranged bouton rows has been yet to determined. 相似文献
19.
Summary On the basis of 44 adult Japanese cadavers, the mode of origin, insertion and innervation of the articularis genus muscle (m. articularis genus: AG) is described. All the muscle bundles that are inserted into the posterior aspect of the synovial membrane of the joint capsule as well as the suprapatellar bursa are defined as AG. The inserting fibers spread medially and laterally over the subsynovial connective tissue which is the outer layer of synovial membrane facing the femur. The fatty tissue between each muscle bundle gradually increases with depth. A few deeper muscle bundles of AG seem to be separated by a layer of fat from those of the superficial layer. The deepest muscle bundles arise from the anterior surface of the femur at a slighlty lower level than the proximal apex of the suprapatellar bursa. It is inserted into the synovial membrane at the level of the junction of the suprapatellar bursa and proper joint cavity when the knee is extended. It is difficult to distinguish AG from m. vastus intermedius (Vi) only on the basis of the manner of origin and the surrounding fatty tissue. The innervation is in common with that of Vi, namely, a few nerves which run down obliquely to the lower medial part of Vi.Dedicated to Professor Emeritus Tomoo Nakayama in commemoration of his 77th birthday 相似文献
20.
Changes in Cell Characteristics Due to Culture Conditions in Cell Lines From Human Small Cell Lung Cancer 总被引:8,自引:0,他引:8
TERASAKI TAKEO; SHISMOSATO YUKIO; NAKAJIMA TAKASHI; TSUMURAYA MASARU; MORINAGA SHOJIROH; HIROHASHI SETSUO; YAMAGUCHI KEN; KATO KANEFUSA; ICHINOSR HIROSHI; NAGATSU TOSHIHARU 《Japanese journal of clinical oncology》1986,16(3):203-212
Eight cultured cell lines were established from human smallcell lung cancers. Every cell line showed the morphologicaland biochemical characteristics of small cell cancer. Changesin cell characteristics were observed in many of these celllines when culture conditions were changed: "oat cell type"changed to "intermediate cell type" and vice versa when serum-freemedium was changed to serum-supplemented medium; a deficiencyof vitamin A in the medium caused a change to squamous cellsand vice versa; and a tumor promoter (teleocidin B) enhancedthe adherence of these cells to the surface of plastic culturedishes. These findings provide evidence that many small celllung cancer cell lines can change their morphology with changesin the environment of the cells. 相似文献