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81.
Harmath A Csaba A Hauzman E Hajdú J Pete B Papp Z 《Journal of clinical ultrasound : JCU》2007,35(5):250-255
PURPOSE: To correlate prenatal sonographic diagnosis of cystic lung malformations with fetopathologic findings after termination of pregnancy. METHODS: We retrospectively analyzed the data of 16 terminated cases in which a cystic lung lesion was diagnosed pre- or postnatally. RESULTS: On average, prenatal diagnosis was established on the 21(st) gestational week (range, 19-26 weeks). The cause of termination was severe polyhydramnios in 4 cases, nonimmune fetal hydrops in 4 cases, other congenital malformation in 5 cases (renal malformation, 2 cases; congenital diaphragmatic hernia, 3 cases), and obstetrical conditions (intrauterine death, placental abruption, spontaneous abortion) in 3 cases. In 11 cases, congenital cystic adenomatoid malformation (CCAM) was the presumptive prenatal diagnosis. Autopsy confirmed the prenatal diagnosis in 6 of them, while in the other 5 cases, an enteric cyst, a laryngeal atresia, an unidentified tumor, a pulmonary hypoplasia, and an extralobar pulmonary sequestration were found on histologic examination. On the other hand, the autopsy revealed CCAM in those 5 cases in which other malformations were suggested prenatally. CONCLUSION: The prenatal sonographic diagnosis of CCAM is difficult. Our cases emphasize the important role of fetopathology even today in the verification of prenatal diagnosis based on sonographic examinations. 相似文献
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83.
目的研究活检术前应用皮质醇是否会影响原发性中枢神经系统淋巴瘤的病理诊断。方法回顾分析2005年2月至2011年2月期间73例经立体定向活检诊断为原发性中枢神经系统淋巴瘤患者的资料。结果 73例淋巴瘤患者中,39例(53.4%)在活检术前应用皮质醇;10例(73;13.7%)未得出阳性结果,再次行立体定向活检或开颅被证实为原发性中枢神经系统淋巴瘤,其中5例(39例)术前应用过皮质醇(12.8%),5例(34例)未使用皮质醇(14.7%)(P=1.0)。结论活检术前应用皮质醇对大部分原发性中枢神经系统淋巴瘤患者而言不影响其病理诊断。 相似文献
84.
Masanori Nakanishi Yoshiki Demura Nobuyuki Kosaka Satoshi Nishikawa Takeshi Ishizaki 《European journal of radiology》2010,73(3):545-550
Background
To diagnose sputum smear-negative pulmonary tuberculosis (PTB) is difficult and the ability of high-resolution computed tomography (HRCT) for diagnosing PTB has remained unclear in the sputum smear-negative setting. We retrospectively investigated whether or not this imaging modality can predict risk for sputum smear-negative PTB.Methods
We used HRCT to examine the findings of 116 patients with suspected PTB despite negative sputum smears for acid-fast bacilli (AFB). We investigated their clinical features and HRCT-findings to predict the risk for PTB by multivariate analysis and a combination of HRCT findings by stepwise regression analysis. We then designed provisional HRCT diagnostic criteria based on these results to rank the risk of PTB and blinded observers assessed the validity and reliability of these criteria.Results
A positive tuberculin skin test alone among clinical laboratory findings was significantly associated with an increase of risk of PTB. Multivariate regression analysis showed that large nodules, tree-in-bud appearance, lobular consolidation and the main lesion being located in S1, S2, and S6 were significantly associated with an increased risk of PTB. Stepwise regression analysis showed that coexistence of the above 4 factors was most significantly associated with an increase in the risk for PTB. Ranking of the results using our HRCT diagnostic criteria by blinded observers revealed good utility and agreement for predicting PTB risk.Conclusions
Even in the sputum smear-negative setting, HRCT can predict the risk of PTB with good reproducibility and can select patients having a high probability of PTB. 相似文献85.
目的探讨肝硬化失代偿期并发意外肝癌患者的肝移植效果及其临床特点。方法11例肝硬化失代偿期患者接受原位肝移植,在术后的病肝病理检查中意外发现癌灶(称之为"意外肝癌"),其原发病,8例为乙型肝炎后肝硬化,丙型肝炎后肝硬化、酒精性肝硬化和原发性硬化性胆管炎各1例。11例术后采用他克莫司、霉酚酸酯及甲泼尼龙预防排斥反应,3个月后撤除霉酚酸酯,6个月后撤除甲泼尼龙。病肝沿水平面作间隔1 cm连续平行切片,对于直径大于1 cm或有灰白色结节者,完整取材。结果11例中,术前仅4例(36.4%,4/11)的甲胎蛋白(AFP)水平超过正常值。除1例肿瘤为多发外,其余均为单发,肿瘤直径最大为2.0 cm,平均直径为1.18 cm;肿瘤TNM分期,Ⅰ期占72.7%,Ⅲ期占27.3%;存在微血管侵犯2例,包膜完整、无血管及淋巴侵犯2例;病理诊断为胆管细胞癌1例,肝细胞癌10例。术后随访12~50个月,1例因肿瘤复发于术后10个月死亡。结论意外肝癌的病理学特点为肿瘤分期早,多为单发,组织分化程度高,肝移植后的1年存活率与良性肝病患者肝移植类似,肿瘤复发率低。 相似文献
86.
87.
Tomasz Dbski Juliusz Wysocki Katarzyna Siennicka Jakub Jaroszewicz Karol Szlzak Wojciech
wiszkowski Zygmunt Pojda 《Materials》2022,15(5)
Poly-ɛ-caprolactone (PCL) is now widely studied in relation to the engineering of bone, cartilage, tendons, and other tissues. Standard histological protocols can destroy the carefully created trabecular and honeycomb-like architecture of PCL scaffolds, and could lead to scaffold fibers swelling, resulting in the displacement or compression of tissues inside the scaffold. The aim of this study was to modify a standard histopathological protocol for PCL scaffold preparation and evaluate it on porous cylindrical PCL scaffolds in a rat model. In 16 inbred Wag rats, 2 PCL scaffolds were implanted subcutaneously to both inguinal areas. Two months after implantation, harvested scaffolds were first subjected to μCT imaging, and then to histopathological analysis with standard (left inguinal area) and modified histopathological protocols (right inguinal area). To standardize the results, soft tissue percentages (STPs) were calculated on scaffold cross-sections obtained from both histopathological protocols and compared with corresponding µCT cross-sections. The modified protocol enabled the assessment of almost 10× more soft tissues on the scaffold cross-section than the standard procedure. Moreover, STP was only 1.5% lower than in the corresponding µCT cross-sections assessed before the histopathological procedure. The presented modification of the histopathological protocol is cheap, reproducible, and allows for a comprehensive evaluation of PCL scaffolds while maintaining their trabecular, honeycomb-like structure on cross-sections. 相似文献
88.
Nanoparticles for colon-drug delivery were designed and evaluated to solve many discrepancy issues such as high adverse effects of released drugs, insufficient drug amount at diseased areas, and unintentionally premature drug release to noninflamed GIT regions. Herein, the goal of this work was to convert trimebutine maleate (TMB) into nanostructured lipid carriers (NLC) in order to improve its protective effects in ulcerative colitis. NLC of TMB was prepared by the hot homogenization followed by ultra-sonication method. A full 42-factorial design was used to estimate the produced TMB-NLC. The study design included the exploration of the impact of two independent variables namely lipid mix amount and ratio (glyceryl mono stearate and capryol 90), surfactant concentration (0.5, 1, 1.5, and 2%), on the particle size, polydispersity index, and the entrapment efficiency (EE%). The protective activity of F9 was examined through macroscopical scores, histopathological changes, immunohistochemical localization of tumor necrosis factor-α (TNF-α) and examination of oxidative stress such as reduced glutathione (GSH), superoxide dismutase (SOD), and malondialdehyde (MDA) against acetic acid-induced colitis in rats. Consistent with our expectations, the orally administered optimized formula (F9) alleviated the severity of colitis in acetic acid-induced rat model of colitis likely owing to the controlled release compared to free TMB. We aimed to develop TMB-loaded NLC for the treatment of acute colitis with the goal of providing a superior drug safety profile over long-term remission and maintenance therapy. 相似文献
89.
Histopathological analysis of cold snare polypectomy and its indication for colorectal polyps 10–14 mm in diameter
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90.
《Pharmaceutical biology》2013,51(4):408-415
Objective: Punarnavashtak kwath (PNK) is a classical Ayurvedic formulation, mentioned in Ayurvedic literature Bhaishajya Ratnavali, for hepatic disorders and asthma. This study investigated the hepatoprotective activity of PNK to validate the traditional use of this formulation.Materials and methods: PNK was prepared in the laboratory according to the method given in Ayurvedic literature. Phytochemical screening was performed to determine the presence of phytoconstituents. Hepatoprotective activity was evaluated against CCl4-induced hepatotoxicity in rats and by its effect on the HepG2 cell line.Results: Preliminary phytochemical screening revealed the presence of alkaloids, tannins, flavonoids, saponins, and a bitter principle in PNK. Administration of PNK produced significant hepatoprotective effect as demonstrated by decreased levels of serum liver marker enzymes such as aspartate transaminase, serum alanine transaminase, serum alkaline phosphatase, and serum bilirubin and an increase in protein level. Thiopentone-induced sleeping time was also decreased in the PNK-treated animals compared with the CCl4-treated group. It also showed antioxidant activity by increase in activity of glutathione, superoxide dismutase, and catalase and by a decrease in thiobarbituric acid reactive substance level compared with the CCl4-treated group. Results of a histopathological study also support the hepatoprotective activity of PNK. Investigation carried out on the HepG2 cell line depicted significant increase in viability of cells exposed to PNK as compared with CCl4-treated cells.Discussion and Conclusion: It can be concluded that PNK protects hepatocytes from CCl4-induced liver damages due to its antioxidant effect on hepatocytes. An in vitro study on HepG2 cell lines also supports its protective effect. 相似文献