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101.
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   
102.
Co-infection with hepatitis B virus (HBV) and hepatitis C Virus (HCV) is associated with increased frequency in the development of hepatocellular carcinoma (HCC). Here, we demonstrated that HBV X protein (HBx) and HCV core cooperate to transform mouse fibroblast NIH3T3 cells. They additively stimulated cell growth, especially in the absence of serum growth factors. In addition, co-expression of HBx and HCV core had additive effects on the induction of anchorage-independent cell growth as well as on the secretion of matrix metalloproteases, which may contribute to increased metastatic potential. Furthermore, the cells expressing both viral proteins exhibited higher tumorigenicity, as demonstrated in athymic nude mice.  相似文献   
103.
A new haplogroup pattern displayed in Fujian Han in China   总被引:1,自引:0,他引:1  
Yu M  Zhang Y  Xue Y  Chen F  Wang Q  Huang X  Wang B  Yu Y  Liu A  Ma L  Shi R  Lu F  Shi Z  Zhang Y  Cheng W  Ai Q  Xu F  Huang C  Chen B  Yang H  Kang X  Sun Y  Zhang G  Li P  Fu S 《Journal of human genetics》2002,47(2):95-98
Human Y-chromosomal binary polymorphisms have been considered to preserve the paternal genetic legacy and provide evidence on human evolution and the genetic relationships among and demographic history of different populations. To reveal the genetic origin and immigration of the Fujian Han, 13 binary markers on the Y chromosome were used to screen Fujian Han by allele-specific polymerase chain reaction. The results indicated that the M9G marker was highly prevalent (96.20%), suggesting a significant genetic drift. In addition, M122C frequency was only 22.78%, and M45A and M103T were default. The distinctive haplogroup frequencies (H1, H5, and H6/7/8) imply that the haplogroup pattern is a relatively ancestral and interim type. Received: October 13, 2001 / Accepted: December 3, 2001  相似文献   
104.
In this paper, the skin blood flow for the stomach and forehead regions of 36 female patients with menstrual symptoms was studied using a moorLDI laser Doppler imager in which the results of 6 typical patients are included. The patterns obtained at the two sites are common to all women in the sample who have menstrual symptoms. Cold stress testing was also investigated to see if it was effective in bringing out any skin blood flow fluctuation at these regions caused by menstrual symptoms. Each patient attended two scanning sessions: one before and the other during menstruation. During each session, the patient was scanned three consecutive times, each on the stomach and the forehead skin regions. For each region, the first measurement was a bare scanning whereas for the second and the third, 85% denatured ethanol (cold stress test) was applied onto the required scan areas. It was found that cold stress testing was able to bring out distinct differences in LDI perfusion images before and during menstruation. Results were best captured when perfusion images were taken approximately after 85% denatured ethanol had been applied in two layers for 30 s, allowed to evaporate over the next 5 min (approximately the time taken to obtain one image), reapplied for another 30 s and then finally over the next 30 s allowed to evaporate further. However, it was impossible to deduce conclusively any correlation regarding migraine and skin blood flow since all the patients for this work had menstrual cramps only.  相似文献   
105.
Radiation therapy is widely used in the treatment of tumor diseases, but it can also cause serious damage to the body, so it is necessary to find effective nutritional supplements. The main purpose of this study is to evaluate the protective effect of whey hydrolysate peptides (WHPs) against 60Coγ radiation damage in mice and explore the mechanism. BALB/c mice were given WHPs by oral gavage administration for 14 days. Then, some mice underwent a 30-day survival test after 8 Gy radiation, and other mice received 3.5 Gy radiation to analyze the changes in body weight, hematology and bone marrow DNA after three and 14 days. In addition, through further analysis of the level of oxidative stress and intestinal barrier function, the possible mechanism of the radioprotective effect of WHPs was explored. The study found WHPs can prolong survival time, restore body weight, and increase the number of peripheral blood white blood cells and bone marrow DNA content in irradiated mice. In addition, WHPs can significantly improve the antioxidant capacity, inhibit pro-inflammatory cytokines and protect the intestinal barrier. These results indicate that WHPs have a certain radioprotective effect in mice, and the main mechanism is related to reducing oxidative damage.  相似文献   
106.
ObjectivesTo evaluate a machine learning model designed to predict mortality for Medicare beneficiaries aged >65 years treated for hip fracture in Inpatient Rehabilitation Facilities (IRFs).DesignRetrospective design/cohort analysis of Centers for Medicare & Medicaid Services Inpatient Rehabilitation Facility–Patient Assessment Instrument data.Setting and ParticipantsA total of 17,140 persons admitted to Medicare-certified IRFs in 2015 following hospitalization for hip fracture.MeasuresPatient characteristics include sociodemographic (age, gender, race, and social support) and clinical factors (functional status at admission, chronic conditions) and IRF length of stay. Outcomes were 30-day and 1-year all-cause mortality. We trained and evaluated 2 classification models, logistic regression and a multilayer perceptron (MLP), to predict the probability of 30-day and 1-year mortality and evaluated the calibration, discrimination, and precision of the models.ResultsFor 30-day mortality, MLP performed well [acc = 0.74, area under the receiver operating characteristic curve (AUROC) = 0.76, avg prec = 0.10, slope = 1.14] as did logistic regression (acc = 0.78, AUROC = 0.76, avg prec = 0.09, slope = 1.20). For 1-year mortality, the performances were similar for both MLP (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.96) and logistic regression (acc = 0.68, AUROC = 0.75, avg prec = 0.32, slope = 0.95).Conclusion and ImplicationsA scoring system based on logistic regression may be more feasible to run in current electronic medical records. But MLP models may reduce cognitive burden and increase ability to calibrate to local data, yielding clinical specificity in mortality prediction so that palliative care resources may be allocated more effectively.  相似文献   
107.
 目的 总结2例人类免疫缺陷病毒(HIV)阴性儿童马尔尼菲篮状菌病(TSM)患儿的临床特征。方法 分析某儿童医院收治的2例HIV阴性TSM患儿的临床特点及实验室资料、存在的基础疾病,并复习相关文献,总结TSM感染患儿的临床特征及诊治经验。结果 2例HIV阴性TSM患儿中病例1以右下肢肿块为首发症状,1个月余后才出现发热及咳嗽,误诊为结核感染;病例2以发热、三系减少及肝脾、淋巴结大等表现起病。病例1行基因检测为STAT1基因突变,病例2有反复灰指甲及口腔溃疡病史,均行血、骨髓培养及淋巴结活检确诊。病例1先后予以伏立康唑、两性霉素B脂质体静脉滴注,伊曲康唑口服维持治疗,共治疗1年后停药;病例2一直予以伏立康唑治疗(先静脉滴注后口服),共7个月后停药,均无复发。结论 TSM可发生在HIV阴性儿童,且可存在STAT1基因突变。对于治疗效果差的患儿,应尽早行培养或组织活检以明确诊断,并积极查找TSM可能存在的基础疾病,以到达早期诊断、早期治疗和改善预后的目的。  相似文献   
108.
We investigated the kinetics of severe acute respiratory syndrome coronavirus 2 neutralizing antibodies in 7 asymptomatic persons and 11 patients with pneumonia. The geometric mean titer of neutralizing antibodies declined from 219.4 at 2 months to 143.7 at 5 months after infection, indicating a waning antibody response.  相似文献   
109.
目的探讨一氧化氮(NO)在老年Ⅱ型糖尿病肾病发病过程中的变化规律及其与肾功能的关系。方法采用Griess法检测48例Ⅱ型DM病人血清NO值在水平及与肾功能有关的指标,并与17例正常人进行比较,结果血清NO值在正常尿蛋白(DMI)组(88.86±9.61umol/l)和微量尿蛋白(DMII)组(90.00±17.94umol/l)明显高于对照组(56.70±9.53umol/l)(P<0.01),至临床肾病期血浆NO浓度明显降低(63.25±8.64umol/l)(P>0.05);NO与BUN、BCR呈负相关,而与CCR呈正相关。结论血清NO水平的动态变化与Ⅱ型DM肾病的发生、发展有密切联系。  相似文献   
110.
目的 :观察心痛安颗粒剂对不稳定性心绞痛患者血小板和凝血系统的作用。方法 :6 0例不稳定性心绞痛患者随机分为心痛安组 (30例 ,常规西药加心痛安颗粒剂治疗 )与对照组 (30例 ,单用常规西药治疗 ) ,观察治疗前后血小板最大聚集率 (Ma% )血小板 α颗粒膜糖蛋白 (GMP- 140 )和 D-二聚体 (D- D)的变化。结果 :治疗后 ,心痛安颗粒组的 Ma% ,GMP- 140和 D- D经治疗后明显下降 ,下降幅度明显大于对照组。结论 :心痛安颗粒剂可能通过抑制血小板聚集、活化和纤维蛋白合成而发挥治疗不稳定性心绞痛的作用。  相似文献   
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