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1.
We describe an 8-year-old boy who had asymptomatic hypercalcemia 4 years after radiotherapy involving the left orbit and lungs. A right parathyroid adenoma was diagnosed, and normocalcemia was achieved after its removal. Routine monitoring of serum calcium and phosphate levels is recommended for children after head and neck irradiation.  相似文献   

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Chemical burns of the eye may destroy all of the corneal epithelium and large portions of conjunctival epithelium into the fornices. Restoration of the ocular surface after a chemical burn depends on the centritedal movement of conjunctival epithelial cells and their adherence to the altered corneal stroma. Epithelial movement after a corneal burn is normal for 72 hours after a burn, but persistent epithelial defects thereafter commonly are not resolved until total corneal vascularization occurs. Although this fresh epithelium may be protected by a bandage soft contact lens, more promising and far-reaching approaches may follow epithelial supplementation and even replacement. The link between the health and integrity of the epithelial layer as it relates to the corneal substratum and its cellular constituents remains to be forged.  相似文献   

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AIMS/BACKGROUND: The causes of blunt ocular trauma are many and diverse. We present two cases of ocular injury caused by an unusual form of weapon called a "Johnny Popper". There follows a theoretical and experimental evaluation of the velocity of the projectiles fired by this device. METHODS: A Johnny Popper was constructed under expert guidance. The elastic properties of the device were measured and this allowed calculation of a theoretical exit velocity of the projectiles fired. The weapon was subsequently fired under test conditions which permitted the exit velocity of the projectiles fired to be measured directly. RESULTS: The theoretical velocity of the projectiles was calculated as 80 ms-1 and the experimentally measured velocity was 57 ms-1. CONCLUSIONS: Johnny Poppers are a previously undescribed and unique form of home made weapon. They are intended for playful mischief, but have the potential to cause serious ocular trauma.  相似文献   

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Three neuroblastoma systems were used to define fucose-containing glycopeptides on the cell surface and to relate them to the phenotypic expressions of neuronal functions. These systems were a) clonal lines of mouse neuroblastoma C-1300, b) cell hybrids of mouse neuroblastoma and rat glioma, and c) human neuroblastomas, primary cells from the tumor, and cell lines. The results suggest that similarities exist in the membrane glycopeptides available at the surface of the mouse and human cells. It is proposed that these similarities correspond to the ability of the cells to perform the differentiated functions of neuronal cells or to exist as tumors. Based on analogy with other cell membranes, a schema is given for the structure of the membrane glycopeptides on the neuroblastoma cell.  相似文献   

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高炉矮式液压泥炮   总被引:1,自引:0,他引:1  
本文针对高炉炉前设备液压泥炮的发展进行概述 ,叙述了目前国内外较为先进的典型矮式液压泥炮 ,PW型、MHG型、IHI型、BG型和DDS型。  相似文献   

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刘毅 《热喷涂技术》2023,15(2):73-79
针对普通喷砂枪“能量利用率较低,喷砂效率特低” 的现状,引入了引射式暂冲型风洞扩压喷气嘴的多孔结构和 Laval 喷管完全膨胀状态设计理念,设计了风洞式喷砂枪。多孔结构缩短了混合距离,是缩小版的风洞扩压喷气嘴,喷砂管之内大部分区域是超声速气流,因而提高了引射效率。进一步地,由于风洞式喷砂枪内部仍残存有亚声速区域,喷砂效率仍未达到压入式喷砂机的水平应与此问题有一定关联性。在风洞喷砂技术的基础上设计了诱导式喷砂枪,以压力诱导方式在喷砂管内部气流全部实现了超声速 ( 超声速气流全域化 ),为砂粒加速创造更加有利的条件;力图打造一款喷砂效率效果赶超压入式喷砂机,且仍然轻便适用的喷砂枪。本文通过 CFD数值模拟喷砂枪内部的流体参数分布说明诱导式喷砂枪改造的新颖性和合理性。  相似文献   

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We studied the in vivo gene transfusion using a gene gun, formerly used in plants and culture cells. The hand-held type gene gun (Helios Gene Gun System) is simple and convenient for effective gene transfection in living animals. This method has some advantages in that there is no need for use of viral vector, independence on the cell cycle and local inducement of plural genes. There is a great possibility for application to local-regional cancer.  相似文献   

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提高喷煤枪使用寿命和减少喷枪冷却用气量,对于防止风口磨损、保证喷煤枪投入数量、减少因风口小套内壁磨损导致的高炉临时休风、降低煤枪使用成本和高炉生产成本具有重要意义。主要介绍宝钢湛江钢铁公司针对普通单管煤枪的不足,自主研发了长寿单管煤枪,重点阐述其技术特点及其实际应用情况,实践证明该长寿单管煤枪使用效果好、寿命长,在生产中应用效果良好。  相似文献   

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The grease gun injury is an uncommon injury to the orbit. However, high-pressure injection of grease, oil, or paint is frequently reported in injuries of the hand and usually affects the fingers or palm, which require complicated surgical and medical care. Two cases of grease gun injury to the orbit are reported: one, a catastrophic injury, and the other resulting in satisfactory recovery after surgical debridement and adjuvant medical treatment. Presentation, investigation, and therapy are discussed.  相似文献   

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OBJECTIVES: This study examined errors in estimating household gun ownership that result from interviewing only 1 adult per household. METHODS: Data from 2 recent telephone surveys and a series of in-person surveys were used to compare reports of household gun ownership by husbands and wives. RESULTS: In the telephone surveys, the rate of household gun ownership reported by husbands exceeded wives' reports by an average of 12 percentage points; husbands' reports also implied 43.3 million more guns. The median "gender gap" in recent in-person surveys is 7 percentage points. CONCLUSIONS: Future research should focus on respondents' reports about personally owned guns.  相似文献   

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We compared the distribution of retinal breaks in retinal detachment between patients with atopic dermatitis (AD) and mentally retarded patients who had self-inflicted ocular injury (MR). The cases of AD were 16 eyes in 14 patients (six males and eight females, ranging in age from 15 to 52 years, mean 24.5) and the cases of MR were 6 eyes in 5 patients (5 males, ranging in age from 14 to 25 years, mean 20.2). There was no corneoscleral laceration in either group. In the patients with AD, 14 (87.5%) of 16 eyes had retinal breaks at the vitreous base, and 21 (87.5%) of 24 retinal breaks in 16 eyes were at the vitreous base. In the patients with MR, five (83.3%) of 6 eyes had retinal breaks at the vitreous base and 6(66.7%) of 9 retinal breaks in 6 eyes were at the vitreous base. In both groups, ciliary epithelial breaks and peripheral retinal tears were frequently observed, suggesting that retinal detachment in AD has a pathophysiology similar to traumatic retinal detachment with repeated ocular contusion (self-inflicted injury).  相似文献   

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Tropomyosins (Tm) are a large family of isoforms obtained from multiple genes and by extensive alternative splicing. They bind in the alpha-helical groove of the actin filament and are therefore core components of this extensive cytoskeletal system. In non-muscle cells the Tm isoforms have been implicated in a diversity of processes including cytokinesis, vesicle transport, motility, morphogenesis and cell transformation. Using immunohistochemical localization in cultured primary cortical neurons with an antibody that potentially identifies all non-muscle TM5 gene isoforms compared with one that specifically identifies a subset of isoforms, the possibility was raised that there were considerably more isoforms derived from this gene than the four previously described. Using polymerase chain reaction (PCR) analysis we have now shown that the rat brain generates at least 10 mRNA isoforms using multiple combinations of terminal exons and two internal exons. There is extensive developmental regulation of these isoforms in the brain and there appears to be a switch in the preferential use of the two internal exons 6a to 6b from the embryonic to the adult isoforms. Specific isoforms using alternate carboxyl-terminal exons are differentially localized within the adult rat cerebellum. It is suggested that the tightly regulated spatial and temporal expression of Tm isoforms plays an important role in the development and maintenance of specific neuronal compartments. This may be achieved by isoforms providing unique structural properties to actin-based filaments within functionally distinct neuronal domains.  相似文献   

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BACKGROUND: Mosaicism of the Helicobacter pylori vac A gene comprises two families of allelic variations of the signal sequence region (s1, s2) and of the mid-region (m1, m2). Initial studies suggested that peptic ulcer disease correlated with the s1 subtype of vac A. We compared the prevalence of various vac A genotypes of H. pylori isolates obtained from duodenal ulcer (DU) patients and subjects with simple gastritis. Those isolates with s1 type were further examined to determine whether the specific vac A s1 (s1a versus s1b) genotype enabled prediction of gastroduodenal disease. METHODS: H. pylori isolates were obtained from 38 patients with endoscopically documented DU and 39 individuals with asymptomatic H. pylori gastritis from Houston, Texas. The vac A genotype of each isolate was determined by polymerase chain reaction (PCR) amplification of genomic DNA for specific regions of the vac A gene. Those isolates with s1 vac A subtype were further examined to determine whether they had s1a or s1b mosaicism. RESULTS: There was no difference in frequency of the s1 genotype of isolates obtained from patients with duodenal ulcer or asymptomatic H. pylori gastritis in this sample (84% versus 79%, respectively; P = 0.77). The s1/m1 vac A genotype was detected in isolates from 16 duodenal ulcer patients versus 15 with H. pylori gastritis (P = 0.82). Detailed analysis of the s1 region failed to show a correlation of either s1a or s1b with duodenal ulcer. Both s1a and s1b genotypes were detected in 24 strains, and both m1 and m2 mid-gene PCR amplicons were seen in 16 strains. CONCLUSIONS: We were unable to use H. pylori vac A genotyping to predict type of gastroduodenal disease in our patient sample. This failure to confirm an association of vac A genotype and duodenal ulcer disease differs from samples from other regions. This most likely represents an example of differences in H. pylori strains infecting host populations in different geographic regions. This study confirms the importance of establishing statistical associations with isolates from widely separate geographic regions before concluding that disease-related associations exist.  相似文献   

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Pilocarpine was administered to a selected group of ocular hypertensive subjects in the form of a synthetic biosoluble matrix inserted into the conjunctival cul-de-sac. Satisfactory lowering of the intraocular pressure resulted, with a minimum of subject intolerance. The decreased pressure response was significant in some cases for greater than 24 hours. Drug delivery by soluble inserts offers promise as a convenient and effective mode of therapy.  相似文献   

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Acute ocular dryness is a morbid condition which occurs when the cornea is suddenly deprived of its natural protection by the eyelids. The reasons for acute ocular dryness are numerous, but superior eyelid trauma often leads to the development of such a pathology. Exposure keratitis is subsequently observed if antibiotics and trophic eyedrops are not prescribed rapidly. An adaptated treatment according to the aetiology must be provided in a department specialized in ophthalmology.  相似文献   

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