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61.
S. Shousha A. Schoenfeld Jill Moss I. Shore H. D. Sinnett 《Ultrastructural pathology》1994,18(5):519-523
Although recent epidemiologic studies suggest that silicone augmentation of the breast is not associated with an increased risk of mammary carcinoma, cases of breast carcinoma arising in augmented breasts are being increasingly encountered as a large number of patients who had augmentation are getting older. A case of a 51-year-old woman with a 20-year history of breast augmentation who developed an invasive cribriform carcinoma associated with extensive microcalcification is presented. The patient had submammary silicone implants 20 years ago that were replaced, because of local complications, in subpectoral positions 10 years later. Dispersive X-ray microanalysis failed to demonstrate silicone in sections of the tumor and adjacent breast tissue. Appropriately fixed tumor tissue was available for electron microscopic examination. The tumor cells were rich in mitochondria, and their luminal surfaces were endowed with abundant microvilli, but the cell surfaces that came closest to the calcified microspheriols were devoid of microvilli and had cellular buddings between the microspheriols. It is suggested that the tumor cells might have been actively involved in the process of microcalcification. 相似文献
62.
Extrinsic risk factors for compromised blood flow in the vertebral artery: anatomical observations of the transverse foramina from C3 to C7 总被引:2,自引:0,他引:2
Cagnie B Barbaix E Vinck E D'Herde K Cambier D 《Surgical and radiologic anatomy : SRA》2005,27(4):312-316
The vertebral artery (VA) is often involved in the occurrence of complications after spinal manipulative therapy. Due to osteophytes
compressing the VA anteriorly from the uncinate process or posteriorly from the facet complex, the VAs are susceptible to
trauma in the transverse foramina. Such altered anatomical configurations are of major clinical significance, as spinal manipulations
may result in dissection of the VA with serious consequences for the blood supply to the vertebrobasilar region. The purpose
of this study is to describe numerous structural features of the third to seventh cervical vertebrae in order to contribute
to the understanding of pathological conditions related to the VA. The minimal and maximal diameter of 111 transverse foramina
in dry cervical vertebrae were studied. The presence of osteophytes and their influence on the VA were evaluated at the vertebral
body and at the superior and inferior articular facets. The diameter of the transverse foramina increased from C3 to C6, while
the transverse foramina of C7 had the smallest diameter. At all levels the mean dimensions of the left foramina were greater
than those of the right side. Osteophytes from the uncinate process of C5 and C6 vertebrae were found in over 60% of dry vertebrae.
Osteophytes from the zygapophyseal joints were more frequent at C3 and C4 vertebrae. About half of the osteophytes of the
uncinate and of the superior articular process partially covered the transverse foramina. This was less common with those
of the inferior articular facets. Osteophytes covering the transverse foramen force the VAs to meander around these obstructions,
causing narrowing through external compression and are potential sites of trauma to the VAs potentially even leading to dissection.
We strongly advocate that screening protocols for vertebrobasilar insufficiency (VBI) be used prior to any manipulation of
the cervical spine and should include not only extension and rotation but any starting position from which the planned manipulation
will be performed. 相似文献
63.
本实验通过对10只家兔双侧推动脉结扎,观察手术前后脑干听觉诱发电位(BAEPs)的变化[1]。结果发现:动物在推动脉结扎后,随时间延长BAEPs各波的波幅逐渐减压,潜伏期逐渐延长;上述变化持续进行40分钟,以后无大变化。提示:BAEPs可以客观地反映椎基底动脉的供血情况。本项研究为临床用BAEPs诊断椎基底动脉供血不足,提供了一项理论依据。 相似文献
64.
Kaoru Takakusaki Jun Kohyama Kiyoji Matsuyama Shigemi Mori 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1993,93(3):471-482
Intrapontine microinjections of serotonin in acutely decerebrated cats resulted in the bilateral augmentation of the postural muscle tone of the hindlimbs. Optimal injection sites were located in the dorsomedial part of the rostral pontine reticular formation corresponding to the nucleus reticularis ponds oralis (NRPo). In this study, attempts were made to elucidate the cellular basis for the serotoninergically induced augmentation of postural muscle tone by recording the electromyographic (EMG) activity of hindlimb extensor muscles, the monosynaptic reflex responses evoked by electrical stimulation of group Ia muscle afferent fibres and the membrane potentials of hindlimb alpha-motoneurons (MNs). Serotonin injections resulted not only in the augmentation of the EMG activity of gastrocnemius soleus muscles, but also in the restoration of EMG suppression, which was induced by previous injection of carbachol into the NRPo. Extensor and flexor monosynaptic reflex responses were facilitated by serotonin injections into the NRPo. Such reflex facilitation was not induced by serotonin injections into the mesencephalic or the medullary reticular formation. Intrapontine serotonin injections resulted in membrane depolarization of extensor and flexor MNs with decreases in input resistance and rheobase. Spontaneous depolarizing synaptic potentials (EPSPs) increased in both frequency and amplitude. Peak voltage of Ia monosynaptic EPSPs also increased. Serotonin injections which followed carbachol injections resulted in membrane depolarization of MNs along with an increase in the frequency of spontaneous EPSPs and a decrease in carbachol-induced inhibitory postsynaptic potentials. Following pontine carbachol injections, antidromic and orthodromic responses in MNs were suppressed. Discharges of MNs evoked by intracellular current injections were also suppressed, but were restored following serotonin injections. These results indicate that postsynaptic excitation, presynaptic facilitation and disinhibition (withdrawal of postsynaptic inhibition) simultaneously act on the hindlimb MNs during serotonin-induced postural augmentation and restoration. 相似文献
65.
《European journal of medical genetics》2020,63(4):103802
Mabry syndrome is a glycophosphatidylinositol (GPI) deficiency characterized by intellectual disability, distinctive facial features, intractable seizures, and hyperphosphatasia. We expand the phenotypic spectrum of inherited GPI deficiencies with novel bi-allelic phosphatidylinositol glycan anchor biosynthesis class O (PIGO) variants in a neonate who presented with intractable epilepsy and complex gastrointestinal and urogenital malformations. 相似文献
66.
Tolbert S. Wilkinson M.D. Barry E. Swartz M.D. I. Richard Toranto M.D. 《Aesthetic plastic surgery》1985,9(2):79-85
Based on prior experience with implant exposure, an aggressive regimen to eradicate periprosthetic infections has proven successful in delayed gram-positive and gram-negative bacterial infections and in atypical microbacterial infections. The objective of the salvage procedure is to retain a prosthesis, to maintain breast contour, and to avoid psychological and physical consequences of prosthesis removal. The salvage procedure involves topical antisepsis, contracture release if needed, systemic and topical antibiotics with intermittent or continuous irrigation, and reinforcement of incision lines in selected cases using local tissue flaps. 相似文献
67.
Rolf Muenker M.D. 《Aesthetic plastic surgery》1984,8(1):37-42
The most common procedures to reconstruct a severe saddle-nose deformity are autogenous costal cartilage, iliac bone grafting, or Silastic implants. Each of them has its specific disadvantages. As an alternative solution, an autogenous bilateral conchal graft in sand-wich technique is described. A 3-layer graft for the dorsum and a 2-layer graft to support the depressed columellar-tip area grants a more natural and elastic reconstruction of the nasal framework. The conchal grafts are taken by an incision made on the preauricular surface of the ear. How to plane the curved grafts by meticulous cross-hatching and to immobilize them in the recipient area by transcutaneous suturing is demonstrated.Presented at the VIII International Congress of Plastic and Reconstructive Surgery, Montreal, Canada, June, 1983 相似文献
68.
69.
Poor tendon to bone healing following rotator cuff repair has led to the continued interest and investigation into biological augmentation. The biology of tendinopathy is not fully understood and consequently the availability of disease modifying therapeutic targets is limited. A ceiling of benefit has been reached by mechanical optimisation of rotator cuff repair and thus, in order to improve healing rates, a biological solution is required. This review focuses on the strategies to biologically augment rotator cuff disorders with an emphasis on rotator cuff repair. Leucocyte rich platelet rich plasma has been shown to improve healing rates without clinically relevant improvements in outcome scores. Similarly, improved healing rates have also been reported with bone marrow stimulation and in long-term follow-up with bone marrow concentrate. Extracellular matrix (ECM) and synthetic scaffolds can increase healing through mechanical and or biological augmentation. A potential third category of scaffold is bio-inductive and has no mechanical support. Studies involving various scaffolds have shown promising results for augmentation of large to massive tears and is likely to be most beneficial when tendon quality is poor, however level I evidence is limited. 相似文献
70.
Sarah Douvier Roland Chapurlat Charline Estublier Pawel Szulc 《Joint, bone, spine : revue du rhumatisme》2021,88(3):105123
IntroductionGiven the prevalence and costs induced by osteoarthritis (OA), it is necessary to find a cheap and safe technique to evaluate it reliably.ObjectiveTo assess the value of the lateral dual energy X-ray absorptiometry (DXA) spine scans for the diagnosis of disc degeneration.MethodSeventy-seven individuals aged 18 and over, with or without disc degeneration, had both lateral thoracolumbar spine radiographs and DXA spine scans (≤ 6 months between both exams). Disc degeneration was assessed using the Lane score. The images of 20 randomly selected individuals were assessed by two readers.ResultsAlmost 13% of the thoracic levels were not assessable on the DXA scans. For the identification of the intervertebral levels on the DXA scans as interpretable or not, the intra-reader agreement was good (κ = 0.81) and the inter-reader agreement was fair (κ = 0.27–0.36). For the diagnostic criteria (osteophytes, disc space narrowing, osteosclerosis, overall grade), the intra-reader agreement was excellent for the radiographs (κ = 0.89–0.92), good for the DXA scans (κ = 0.64–0.83) and fair to moderate for the between-method comparison (κ = 0.25–0.44). The inter-reader agreement was moderate to good for the radiographs (κ = 0.49–0.66) and fair to good for the DXA scans (κ = 0.32–0.74). In the per patient analysis (the most severe grade), the intra-reader agreement was excellent for the radiographs (κ = 0.85–0.94), moderate to excellent for the DXA scans (κ = 0.53–0.85) and poor to good for the between-methods comparison (κ = 0.17–0.63).ConclusionOur results do not support the use of DXA scans for the assessment of thoracolumbar disc degeneration. 相似文献