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91.
A 41-year-old male presented with an ill-demarcated mass involving the left fronto-temporal lobe and the basal ganglia. Light microscopically the tumor was diagnosed as an anaplastic oligoastrocytoma. Electron microscopy revealed several cytoplasmic crystalline inclusions in tumor cells of oligodendroglial lineage. No crystalline inclusions were membrane bound. The morphologic features with unique ultrastructural findings are presented. 相似文献
92.
93.
Chung JP Chi SW Park YN Lee SJ Song SY Lee KS Chung JB Lee SI Kang JK Kim KW Chi HS 《Yonsei medical journal》2000,41(4):528-532
Intraductal papillary mucinous tumor (IPMT) of the pancreas, a lesion consisting of mucin-producing cells with neoplastic potential, is characterized by duct ectasia, mucin hypersecretion, often extensive papillary intraductal growth, varying degrees of cytologic atypia, and relatively indolent growth. The clinical presentation of IPMT of the pancreas is characterized by chronic or recurrent attacks of abdominal discomfort often in association with low level pancreatic enzyme elevations. Less commonly these lesions may be detected as asymptomatic radiographic abnormalities. Interestingly, a case of a minute IPMT (2 mm in height and 7 mm in length, adenoma) in the main pancreatic duct presenting with acute pancreatitis in a 55 year-old man has been reported in the Japanese literature. Recently, we also experienced a case of a minute IPMT in a branch pancreatic duct causing repeated bouts of acute pancreatitis in a 75 year-old man. A filling defect at the neck of the main pancreatic duct seen on an endoscopic retrograde pancreatogram performed after recovery of the second attack of acute pancreatitis led the patient to undergo an exploratory laparotomy. After a near-total pancreatectomy was carried out, a minute (3 x 7 mm) IPMT of borderline malignancy was discovered in a branch duct at the head portion near the pancreatic neck without any lesions in the main pancreatic duct. Surprisingly, despite the resective surgery the patient died of carcinomatosis 8.5 months after the operation. We herein report a case of a minute but aggressive IPMT of the pancreas with a review of the literature. 相似文献
94.
High prevalence of Helicobacter pylori in saliva demonstrated by a novel PCR assay. 总被引:12,自引:1,他引:12
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C Li P R Musich T Ha D A Ferguson Jr N R Patel D S Chi E Thomas 《Journal of clinical pathology》1995,48(7):662-666
AIMS--To investigate the prevalence of Helicobacter pylori in the saliva of patients infected with this bacterium. METHODS--A novel polymerase chain reaction (PCR) assay was developed to detect H pylori in saliva and gastric biopsy specimens from patients undergoing endoscopy. RESULTS--Our PCR assay amplified a 417 base pair fragment of DNA from all 21 DNAs derived from H pylori clinical isolates but did not amplify DNA from 23 non-H pylori strains. Sixty three frozen gastric biopsy and 56 saliva specimens were tested. H pylori specific DNA was detected by PCR in all 39 culture positive biopsy specimens and was also identified from another seven biopsy specimens which were negative by culture but positive by histology. H pylori specific DNA was identified by PCR in saliva specimens from 30 (75%) of 40 patients with H pylori infection demonstrated by culture or histological examination, or both, and in three patients without H pylori infection in the stomach. CONCLUSION--The results indicate that the oral cavity harbours H pylori and may be the source of infection and transmission. 相似文献
95.
Characterization of Group B Streptococcal Invasion of Human Chorion and Amnion Epithelial Cells In Vitro 总被引:6,自引:2,他引:6
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Scott B. Winram Mechthild Jonas Emil Chi Craig E. Rubens 《Infection and immunity》1998,66(10):4932-4941
Group B streptococci (GBS) have been cultured from the chorioamnionic membrane of pregnant women, usually in association with chorioamnionitis and premature labor (K. A. Boggess, D. H. Watts, S. L. Hillier, M. A. Krohn, T. J. Benedetti, and D. A. Eschenbach, Obstet. Gynecol. 87:779–784, 1996). Colonization and infection of placental membranes can be a prelude to neonatal GBS infections even in the presence of intact membranes (R. L. Naeye and E. C. Peters, Pediatrics 61:171–177, 1978), suggesting that GBS cause chorioamnionitis or establish amniotic fluid infections by partial or complete penetration of the placental membranes. We have isolated and grown cultures of primary chorion and amnion cells from human cesarean-section placentas. This has provided a biologically relevant model for investigating GBS adherence to and invasion of the two epithelial barriers of the placental membrane. GBS adhered to chorion cell monolayers to a high degree. Pretreatment of GBS with trypsin reduced adherence up to 10-fold, which suggested that the bacterial ligand(s) was a protein. GBS invaded chorion cells at a high rate in vitro, and invasion was dependent on cellular actin polymerization. GBS could be seen within intracellular vacuoles of chorion cells by transmission electron microscopy. We also demonstrated that GBS were capable of transcytosing through intact chorion cell monolayers without disruption of intracellular junctions. GBS also adhered to amnion cells; in contrast, however, these bacteria failed to invade amnion cells under a variety of assay conditions. GBS interactions with the chorion epithelial cell layer shown here correlate well with epidemiological and pathological studies of GBS chorioamnionitis. Our data also suggest that the amnion cell layer may provide an effective barrier against infection of the amniotic fluid. 相似文献
96.
Olubusola Oladeji Chi Zhang Tiam Moradi Dharmesh Tarapore Andrew C Stokes Vukosi Marivate Moinina D Sengeh Elaine O Nsoesie 《JMIR Public Health and Surveillance》2021,7(4)
BackgroundThe prevalence of chronic conditions such as obesity, hypertension, and diabetes is increasing in African countries. Many chronic diseases have been linked to risk factors such as poor diet and physical inactivity. Data for these behavioral risk factors are usually obtained from surveys, which can be delayed by years. Behavioral data from digital sources, including social media and search engines, could be used for timely monitoring of behavioral risk factors.ObjectiveThe objective of our study was to propose the use of digital data from internet sources for monitoring changes in behavioral risk factors in Africa.MethodsWe obtained the adjusted volume of search queries submitted to Google for 108 terms related to diet, exercise, and disease from 2010 to 2016. We also obtained the obesity and overweight prevalence for 52 African countries from the World Health Organization (WHO) for the same period. Machine learning algorithms (ie, random forest, support vector machine, Bayes generalized linear model, gradient boosting, and an ensemble of the individual methods) were used to identify search terms and patterns that correlate with changes in obesity and overweight prevalence across Africa. Out-of-sample predictions were used to assess and validate the model performance.ResultsThe study included 52 African countries. In 2016, the WHO reported an overweight prevalence ranging from 20.9% (95% credible interval [CI] 17.1%-25.0%) to 66.8% (95% CI 62.4%-71.0%) and an obesity prevalence ranging from 4.5% (95% CI 2.9%-6.5%) to 32.5% (95% CI 27.2%-38.1%) in Africa. The highest obesity and overweight prevalence were noted in the northern and southern regions. Google searches for diet-, exercise-, and obesity-related terms explained 97.3% (root-mean-square error [RMSE] 1.15) of the variation in obesity prevalence across all 52 countries. Similarly, the search data explained 96.6% (RMSE 2.26) of the variation in the overweight prevalence. The search terms yoga, exercise, and gym were most correlated with changes in obesity and overweight prevalence in countries with the highest prevalence.ConclusionsInformation-seeking patterns for diet- and exercise-related terms could indicate changes in attitudes toward and engagement in risk factors or healthy behaviors. These trends could capture population changes in risk factor prevalence, inform digital and physical interventions, and supplement official data from surveys. 相似文献
97.
目的建立一种血清硝酸盐的快速测定方法.方法血清经去蛋白后,直接在酸性条件下用麝香草酚显色分光光度法测定.结果方法的检测下限为0.05μg,相对标准差为4.6%~9.6%,回收率为90.0%~95.9%(平均为93.6%).血清硝酸盐氮含量为0.13±0.011μg时,批间变异系数为8.6%.结论本法快速、简便、灵敏、特效性好,适用于血清中NO3-测定. 相似文献
98.
复方磺胺嘧啶锌涂膜剂治疗烧伤的疗效观察 总被引:6,自引:1,他引:5
目的 观察复方磺胺嘧啶锌涂膜剂治疗浅Ⅱ度、深Ⅱ度 烧伤创面、残余创面抗感染和促进创面愈合的作用。方法 治疗组清 创 后应用复方磺胺嘧啶锌涂膜剂涂于创面的表面,对照组应用1%磺胺嘧啶银霜覆盖创面,共治 疗119例烧伤患者(即222个创面),包括浅Ⅱ度烧伤、深Ⅱ度烧伤、残余小创面及供皮区创面 ,并观察创面完全愈合时间、创面表面细菌培养用药前与用药中的情况以及复方磺胺嘧啶锌 涂膜剂对全身情况的影响。结果 浅Ⅱ度烧伤创面治疗组(10.25±1 .6 9)天完全愈合,对照组(13.15±2.03)天愈合;深Ⅱ度创面治疗组(18.10±2.72)天愈合 ,对照组(21.2±3.64)天愈合,治疗组明显优于对照组(P<0.05);治疗组用药前细 菌培养阳性率是38.8%,治疗中降至9.0%;对照组用药前细菌培养阳性率为32.7%,治疗 中降至25.4%;两组间比较具有显著性差异(P<0.05);患者未出现疼痛、过敏反应 和其它不良反应。结论 复方磺胺嘧啶锌涂膜剂治疗烧伤创面可促进上 皮 化、加速创面愈合、有效地防治创面感染,该药应用简便、适用于社区、基层常见的中、小 面积浅度烧伤治疗。 相似文献
99.
Anaemia is highly prevalent at the time of intensive care unit discharge and is persistent for a high proportion of intensive care unit survivors. Whether anaemia is a driver of impaired recovery after critical illness is uncertain. The aim of this study was to test the hypothesis that, in adult intensive care survivors, anaemia at the time of intensive care unit discharge independently predicts decreased days at home-90. This retrospective cohort study was conducted in a tertiary intensive care unit in Perth, Western Australia. All patients aged ≥ 16 years, discharged alive from their index intensive care unit admission and without documented treatment limitations were included. Median (IQR [range]) age of the 6358 participants was 61 (46–72 [16–95]) years and included 3385 (53.2%) unplanned admissions. Intensive care unit discharge with a haemoglobin concentration < 100 g.l-1 occurred in 2886 (45.4%) patients, a threshold that identified a cohort with significantly lower days at home-90 (median (IQR [range]) 80 (64–85 [0–90]) days vs. 85 (77–88 [0–90]) days (median difference 5 days, 95%CI 4.4–5.5, p < 0.0001). The association followed a severity-response relationship with more severe anaemia predicting lower days at home-90. When accounting for prespecified covariates including admission haemoglobin concentration and red blood cell transfusion, anaemia at intensive care unit discharge remained a significant predictor of decreased days at home-90, relative risk 0.96 (0.93–0.98), p < 0.002. These findings support the need for interventional trials investigating whether this risk is modifiable. 相似文献
100.
Xu Li Siming Li Zhihong Chi Chuanliang Cui Lu Si Xieqiao Yan Lili Mao Bin Lian Bixia Tang Xuan Wang Xue Bai Li Zhou Yan Kong Jie Dai Jun Guo Xinan Sheng 《Urologic oncology》2021,39(1):75.e1-75.e8
PurposeTo investigate the clinical characteristics, chemosensitivity, and outcome of metastatic upper tract urothelial carcinoma (UTUC).Patients and MethodsRecords of patients with metastatic UTUC since January 2005 were retrieved from a database that included clinical and survival data. Statistical analyses including survival and multivariate analyses of factors were respectively performed by the Kaplan-Meier method and Cox proportional hazard model.ResultsA total of 250 consecutive UTUC cases were evaluated. There were 56 patients (22.4%) with initially diagnosed stage IV disease. The most common metastatic sites were lung (39.6%), distant lymph nodes (39.2%), bone (19.6%), liver (18.0%), and adrenal gland (7.2%), respectively, and the local recurrence rate was 10.4%. Two hundred thirteen patients received first-line chemotherapy. The overall response rate was only 28.7% and the median progression-free survival time was only 5.0 months. The overall survival time of the cohort was 18.0 months. Multivariate analyses showed that initially diagnosed stage IV disease, number of metastatic organs ≥3, no response to chemotherapy and cycles of chemotherapy ≤2 were adverse prognosticators for overall survival.ConclusionUTUC presented to be more prone to metastasize than locally recur and thought to have low chemosensitivity. Stage IV disease at initial diagnosis, number of metastatic organs, response and cycles of chemotherapy were independent prognosticators for metastatic UTUC. 相似文献