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91.
Lester D. R. Thompson 《Head and neck pathology》2021,15(1):120
Fibroinflammatory lesions of the sinonasal tract are one of the most common head and neck lesions submitted to surgical pathology. When the fibroinflammatory pattern represents the lesion (i.e., not surface reactive ulceration), an algorithmic approach can be useful. Separated into reactive, infectious, and neoplastic, and then further divided based on common to rare, this logical progression through a series of differential considerations allows for many of these lesions to be correctly diagnosed. The reactive lesions include chronic rhinosinusitis and polyps, granulomatosis with polyangiitis, and eosinophilic angiocentric fibrosis. Infectious etiologies include acute invasive fungal rhinosinusitis, rhinoscleroma, and mycobacterial infections. The neoplastic category includes lobular capillary hemangioma, inflammatory myofibroblastic tumor, and NK/T-cell lymphoma, nasal type. Utilizing patterns of growth, dominant cell types, and additional histologic features, selected ancillary studies help to confirm the diagnosis, guiding further clinical management. 相似文献
92.
BackgroundMarjolin’s ulcers are a rare form of malignancy that present at regions exposed to chronic infection. They present with a clinical triad of nodularity, induration, and ulceration greater than 3 months.Case reportWe present herein, an extremely rare case of Marjolin’s ulcer of the forearm, secondary to osteomyelitis, resulting from a 30-year neglection of external fixator used to treat a war injury of the forearm.DiscussionMarjolin’s ulcers are classically encountered in lower extremities at sites of burns, trauma or complicated wounds. In the upper extremity however, they are seldom mentioned in literature. The presence of risk factors raise the suspicion of the disease.ConclusionMarjolin’s ulcer is rare sequelae of chronic wound infection. Patients often present after a latency period with exacerbated pain, discharge, and exophytic mass. This disease should be suspected in every case of chronic ulcer, where histological studies of the lesion must be conducted to exclude or confirm the diagnosis. 相似文献
93.
本文用多种单克隆抗体对32例慢性肝炎患者的细胞免疫状况进行了研究。结果发现患者肝组织内淋巴细胞和单核、巨噬细胞浸润明显增加,坏死区浸润细胞主要是T_3~+和T_8~+细胞。B淋巴细胞浸润极少,浸润淋巴细胞表面IL—2受体阳性细胞与外周血淋巴细胞表面IL—2受体阳性细胞率均无改变。患者外周血单个核细胞改变为T_3~+下降,T_4/T_8比例下降,单核、巨噬细胞、B淋巴细胞及淋巴细胞表面HLA—DR、DP、DQ标志与正常人无差异。 相似文献
94.
David P. Bazett-Jones Ren Li Eden Fussner Rosa Nisman Hesam Dehghani 《Chromosome research》2008,16(3):397-412
Electron microscopy has been the ‘gold standard’ of spatial resolution for studying the structure of the cell nucleus. Electron
spectroscopic imaging (ESI) offers advantages over conventional transmission electron microscopy by eliminating the need for
heavy-atom contrast agents. ESI also provides mass-dependent and element-specific information at high resolution, permitting
the distinguishing of structures that are primarily composed of protein, DNA, or RNA. The technique can be applied to understand
the structural consequences of epigenetic modifications, such as modified histones, on chromatin fiber morphology. ESI can
also be applied to elucidate the multifunctional behavior of subnuclear ‘organelles’ such as the nucleolus and promyelocytic
leukemia nuclear bodies.
The authors dedicate this paper to the memory of Ying Ren (1961–2007). We all benefited from knowing her. Our research advanced
through the technical creativity she provided. 相似文献
95.
《Medical Journal Armed Forces India》2023,79(1):40-45
BackgroundChronic wounds are of many etiologies and difficult to treat. Many commercial products to manage such wounds are available, which claim to have good outcomes. Aim of this study was to compare the efficacy of Ionic Silver Solution and Super Oxidized Solution in the management of chronic wounds.MethodsPatients with chronic wounds were randomly placed in two groups-Group A (Ionic Silver Solution) and Group B (Super Oxidized Solution) with 30 patients each. The dressings were continued until the wound healed completely or the wound was ready for a definitive procedure. Wound parameters were recorded as per Bates Jensen Wound Assessment Tool (BJWAT) Score.ResultsFIfty patients completed the study. The scores were compared at the initiation and endpoint of treatment. The pretreatment total for BJWAT was 916 and 924 in group A and group B respectively, which was not statistically significant. Post-treatment improvement was noticed in both the groups and the score decreased to 510 and 675 in group A and group B respectively (p = 0.001). Ionic Silver Solution and Super Oxidized Solution both were found to be effective in improving the overall wound condition. However, Ionic Silver Solution was found to be more effective than Super Oxidized Solution in the healing of chronic wounds. Complete healing was noticed in a small number (6%) of patients. These agents can therefore best prepare the wounds for early surgical intervention.ConclusionBoth the agents were found to be safe and useful in the management of chronic wounds. However, Ionic Silver Solution was found to be more effective than the super oxidized solution in this study. 相似文献
96.
Regional alterations of brain biogenic amines and GABA/glutamate levels in rats following chronic lead exposure during neonatal development 总被引:1,自引:0,他引:1
Wistar rat pups were administered either a high dose of lead acetate (400 g lead/g body weight/day) or a low dose (100 g lead/g body weight/day) by gastric intubation, from 2 days through 60 days of age. The rats on both these doses exhibited statistically significant decreases in body and brain weights throughout the lead treatment period. A group of rats on high dose was also rehabilitated by discontinuing the lead from 60 days of age. In these rats, at 160 days of age, the body weight but not the brain weight recovered to normal levels. During the lead intake, the rats on high dose revealed significant elevations in the levels of noradrenaline (NA) in the hippocampus (HI), cerebellum (CE), hypothalamus (HY), brainstem (BS), and accumbens-striatum (SA). The elevated levels in all the above regions except in the HY persisted even after rehabilitation. The dopamine (DA) levels changed significantly in opposite directions in HY (elevation) and BS (reduction) during the lead treatment, and the HY recovered after rehabilitation. Under lead, the serotonin (5HT) levels were elevated significantly in the HI, BS and MC (motor cortex), while after rehabilitation the abnormality persisted only in the MC. Low dose lead treatment was also effective on the same areas of brain. In the low dose group, estimation of the levels of GABA and glutamate were also done, and a significant decrease of GABA in CE and glutamate in MC was observed. The differences observed in the neurotoxic effects (none or significant) of lead in the different regions for each of the transmitters (NA, DA, 5HT) supports the interesting conclusion that the vulnerability of the axon terminals of any given type is dependent on some regional factors, although the projections of the different regions originate from an apparently similar category of neurons in the brain stem. 相似文献
97.
The effect of chronic subcutaneous administration of lead acetate was studied in female rabbits. The low-dose group (15 animals) received three times a week 0.10–0.20 g/kg body weight and the high-dose group (15 animals) 0.80–1.20 g/kg. The control group received the vehicle only. Concentrations of lead in blood in the low-dose group increased to ca. 400 g/l after 70 days and in the high-dose group to ca. 900 g/l after 110 days. After 7.5 months eight animals of each group were sacrificed. The remaining rabbits were kept for an additional 4 months without treatment. Blood lead concentrations decreased with a half-time of 60–70 days. During exposure the gain in body weight was lower in the high-dose group than in the control group and the low-dose group. The high-dose group developed slight anaemia and low MCV, MCH and MCHC, and basophilic stippling of erythrocytes. These effects disappeared during recovery. ALAD activity in erythrocytes was very low during exposure in both exposed groups and did not reach control values during recovery. During exposure the concentrations of ZPP and ALA-U increased, but only ALA-U returned to normal during recovery. No other effects of lead on the composition of the urine were observed. No effects were observed on plasma urea and creatinine concentrations. In the highdose group the concentration of ALAD in the liver decreased by 30%. During recovery this effect was no longer present. No effects were seen in cytochrome P-450 content or cytochrome P-450-dependent enzyme activities. Lead was mainly stored in bones, but some also in serveral soft tissues. After recovery the concentrations in soft tissues decreased to a variable degree. In the high-dose group the relative weights of heart and liver increased. These effects disappeared during recovery. At 400 g lead/l blood no adverse effects were observed that did occur at the high dose level.Part 2, dealing with the histopathology and (electron) microscopy of the kidneys is in preparation 相似文献
98.
为了探讨红细胞膜Ca运转对慢性肾功能不全的影响,我们应用放射性同位素~(45)Ca示踪技术对15例慢性肾功能不全者进行红细胞膜钙内流(Ecc)及钙泵活性(Ecp)检测,并使用氨氯地平进行干预,结果发现:①慢性肾功能不全Ecc高于正常组;Ecp低于正常组。②经氨氯地平5~10mg每日1次干预4~6周后检测,Ecc下降,Ecp升高。BUN、Cr、24h尿蛋白均改善,初步显示了氨氯地平延缓肾衰进展的效果。 相似文献
99.
何良新 《中国自然医学杂志》2000,2(4):216-217
目的 了解导赤散加味对慢性前列腺炎的疗效。方法 应用导赤散为主组方,结合直肠指诊、化验检查进行综合分析,辨证加减用药、治疗慢性前列腺炎110例,并与口服环丙沙星片、回通淋丹组40例作对照。结果 治疗组近期治愈率36.4%,总有效率为91.0%,对照组近期治愈率仅15.0%,总有效率为72.5%,两组的有效率比较差异有显性(P<0.05)。结论 导赤散加味治疗慢性前列腺炎有明显改善作用。 相似文献
100.
为进一步研究呼吸道疾病时的粘液纤毛清除功能,采用99mTc-DTPA气溶胶吸入显像,通过电影显示定性和定量指标分析.对18 例健康受试者和患者进行了显像研究,得到气道清除率和粘液纤毛清除率的正常值,并观察了32例慢性阻塞性肺病(COPD)患者气管-支气管纤毛清除功能的改变.结果显示,健康受试者与COPD患者粘液纤毛清除率(mm/min)分别为3.89±0.92和1.32±0.59,两者比较有显著性差异(P<0.01),COPD患者不同时间气道清除率和粘液纤毛清除率均明显低于健康受试者(P<0.01).本研究方法简便客观,具有定性观察和定量分析的优点,对于呼吸系统其它疾病(如支气管扩张、原发性纤毛无运动)的研究及药物疗效的评价具有重要的临床实用价值. 相似文献