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排序方式: 共有5843条查询结果,搜索用时 31 毫秒
1.
Jianhui Su Chaoyang Ma Chengxiang Liu Chuanzhong Gao Rongjing Nie 《International journal of food sciences and nutrition》2016,67(1):20-28
This study investigated the hypocholesterolaemic effects of bitter melon aqueous extracts (BMAE) in vitro, the inhibitory effects of BMAE on pancreatic cholesterol esterase (CEase) and incorporation of cholesterol into micelles were investigated. BMAE decreased the in vitro micellar solubility of cholesterol in a dose-dependent manner. The conformation of CEase was investigated by means of circular dichroism (CD) and fluorescence. The result revealed the decrease of α-helix contents, increase of β-sheet and exposure of aromatic amino acid residuals. The incorporation of cholesterol into micelles was inhibited by BMAE. A complex was observed by transmission electron microscopy (TEM), which indicated interaction between cholesterol and BMAE. The result revealed that BMAE can play a role in decreased intestinal cholesterol absorption via inhibition of CEase, and of micelle formation. 相似文献
2.
白纹伊蚊在竹林里孳生的阳性比为75.4%;而在竹林包围的居民区阳性比为15.3%。白纹伊蚊在居民区孳生密度布雷图指数为19.4,容器指数为6.2%。居民区孳生蚊虫的主要场所是泡菜坛,泡菜坛主要孳生蚊种是骚扰阿蚊,阳性比为73.7%,其次是淡色库蚊为20.2%,贪食库蚊为14.0%,白纹伊蚊最低,为9.1%。 相似文献
3.
Yongkang Nie Qiang Li Feng Li Yonglin Pu Daniel Appelbaum Kunio Doi 《Journal of nuclear medicine》2006,47(7):1075-1080
Our objective was to develop and evaluate 3 semiautomatic computer-aided diagnostic (CAD) schemes for distinguishing between benign and malignant pulmonary nodules by use of features extracted from CT, 18F-FDG PET, and both CT and 18F-FDG PET. METHODS: We retrospectively collected 92 consecutive cases of pulmonary nodules (<3 cm) in patients who underwent both thoracic CT and whole-body PET/CT. Forty-two of the nodules were malignant and 50 benign, as confirmed by pathologic examination and clinical follow-up. The interval between CT and PET was less than 1 mo. Four clinical parameters, including patient age, sex, smoking status, and history of previous malignancy, were used for the CAD schemes. Sixteen CT features based on size, shape, margin, and internal structure of nodules were independently rated subjectively by 2 chest radiologists. Four PET features were viewed on a PET/CT workstation. CAD schemes based on clinical parameters together with CT features, PET features, and both CT and PET features were then used to differentiate benign from malignant nodules. Finally, the output from the CAD schemes was evaluated by use of receiver-operating-characteristic analysis. RESULTS: When we used clinical parameters and CT features as input units (CAD scheme 1), the area under the receiver-operating-characteristic curve (A(z) value) of the CAD scheme was 0.83. When we used clinical parameters and PET features as input units (CAD scheme 2), the A(z) value for the computer output was 0.91. However, when we used all data as input units (CAD scheme 3), the A(z) value for the computer output was 0.95. The performance of CAD scheme 3 was better than that of CAD scheme 1 or 2. A statistically significant difference existed between the A(z) values of CAD schemes 3 and 2 (P = 0.037) and between those of CAD schemes 3 and 1 (P = 0.015). CONCLUSION: Our CAD scheme based on both PET and CT was better able to differentiate benign from malignant pulmonary nodules than were the CAD schemes based on PET alone and CT alone. 相似文献
4.
Yulu Miao Mingxia Zhang Yulin Nie Wan Zhao Bin Huang Zhengming Jiang Shaoxiong Yu Zhibin Huang Hongjin Fu 《中国神经再生研究》2007,2(2):126-128
BACKGROUND: Besides local changes of cranial parenchymal cells, hemorrhage, etc., severe traumatic brain injuries also cause the changes of total body fluid and various functions, and the changes of lymphocytes and T lymphocyte subsets should be paid more attention to. OBJECTIVE: To reveal the changing laws of T lymphocyte subsets after severe traumatic brain injury, and compare with mild to moderate brain injury. DESIGN: A comparative observation. SETTINGS: Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City; Central Laboratory of Shenzhen Hospital of Prevention and Cure for Chronic Disease. PARTICIPANTS: All the subjects were selected from the Department of Neurosurgery, Longgang District Buji People's Hospital of Shenzhen City from August 2002 to August 2005. Thirty patients with severe brain injury, whose Glasgow coma score (GCS) was ≤ 8 points, were taken as the experimental group, including 21 males and 9 females, aging 16 - 62 years. Meanwhile, 30 patients with mild traumatic brain injury were taken as the control group (GCS ranged 14- 15 points), including 18 males and 12 females, aging 15 -58 years. All the subjects were in admission at 6 hours after injury, without disease of major organs before injury Informed consents were obtained from all the patients or their relatives. METHODS: (1) The T lymphocytes and the subsets in peripheral blood were detected with immunofluorescent tricolor flow cytometry at l, 3, 7 and 14 days after injury in both groups. (2) The conditions of pulmonary infections were observed at 4 days after injury. The differences of measurement data were compared with the t test. MAIN OUTCOME MEASURES: Changes of T lymphocytes subsets at 1 - 14 days after severe and mild or moderate traumatic injury. RESULTS: Finally, 28 and 25 patients with mild to moderate traumatic brain injury, whereas 25 and 21 patients with severe traumatic brain injury were analyzed at 7 and 14 days respectively, and the missed ones died due to the development of disease. (1) Changes of T lymphocyte subsets: At 1 and 3 days after injury, CD3, CD4, CD8, CD4/CD8 began to decrease, whereas CD8 increased in the experimental group, which were very significantly different from those in the control group (t =2.77 - 3.26, P 〈 0.01), and began to recover at 7 days, which were significantly different from those in the control group (t = 2.06 - 2.24, P 〈 0.05), and generally recovered to the normal levels at 14 days (P 〉 0.05). (2) Conditions of pulmonary infections: At 4 days after injury, the rate of pulmonary infection was significantly different between the experimental group and control group [73% (22/30), 0, x2=37.29, P 〈 0.01]. CONCLUSION: Patients with severe traumatic brain injury suffer from damages of cellular immune function at early period (within 7 days), and they are easily to be accompanied by pulmonary infections. 相似文献
5.
6.
目的:探讨重症胆管(ACST)患者的临床特点及死亡原因。方法:分析我院近十五年来收治46例ACST的治疗情况。结果:手术41例.非手术5例,死亡9例,其中手术治疗死亡6例。结论:老年ACST患者,伴发病多,死亡率高,及时就诊,早期应用大量激素,选择适宜手术方法是降低死亡率的关键。 相似文献
7.
魏嘉平 王香平 张建 王力红 刘佑琴 冯明 贾强 杨强 聂秀红 李坤成 尹建国 王立 续大田 张泰昌 王育琴 韩玫 王克杰 李宗信 丁秀娟 徐玲 吴晓光 汤哲 《首都医科大学学报》2003,24(4):374-379
为分析严重急性呼吸综合征(SARS)死亡患者的临床特征、治疗及死亡相关因素,对2003年5月6日至6月27日收治的220例SARS患者中19例死亡患者的临床、实验室、影像学资料、临床治疗及死亡相关因素进行回顾性分析。结果19例死亡SARS患者年龄24~86岁,平均(57.63±16.76)岁。大于45岁13例(68.4%)。男性15例(78.9%),女性4例(21.1%)。有明确接触史19例(100%)。并存基础病13例(68.4%)。死亡距发病时间14~54d,平均(35.37±11.66)d。临床表现主要有发热19例(100%),咳嗽12例(63.2%),畏寒5例(26.3%),气促10例(52.6%),胸闷11例(57.9%),肌痛5例(26.3%),腹泻6例(31.6%)。实验室检查血常规中早期白细胞总数正常或降低,淋巴细胞降低。血气分析低氧血症16例(84.2%);心肌酶肌酸激酶心肌型同工酶(CKMB)、乳酸脱氢酶(LDH)、α羟丁酸脱氢酶(HBDH)随病情的严重程度而进行性升高。T细胞亚群CD3、CD4、CD8绝对值随病情的严重程度而进行性降低。胸部X线双侧、肺病变面积>1/3者19例(100%)。临床诊断继发混合感染(细菌、真菌)19例(100%)。采用综合治疗,其中激素18例(94.7%)、机械通气15例(78.9%)。死于呼吸衰竭18例(94.7%)。提示年龄、合并基础病、肺部病变程度、低氧血症、T细胞亚群CD3、CD4绝对值降低、激素剂量、混合感染等是影响S 相似文献
8.
目的 探讨羧乙基锗倍半氧化物(Ge-132)在乙醇致体内脂质过氧化过程的抑制作用及机理。方法 用10mg/kg体重的乙醇给大鼠灌胃,同时自由饮用100mg/L的锗-132,饲养3个月。结果 乙醇+Ge-132组大鼠组织和血清与单给乙醇组比较DMA含量显著降低(P<0.05),SOD、CAT活力均升高(P<0.05),但与对照组比较均无显著性差异(P>0.05)。结论 Ge-132通过清除OH^.和O2^.-自由基,抑制SOD、CAT活力降低,从而抑制过量乙醇对机体的损伤。 相似文献
9.
Hideki Amano Kuniyoshi Ohara Masaki Nie Yutaka Miyoshi Hirokuni Yoshimura 《Annals of thoracic and cardiovascular surgery》2002,8(6):389-392
We experienced two cases of left ventricular free wall rupture (LVFWR) following acute myocardial infarction (AMI). Case 1, with the blowout type of LVFWR was initially closed by direct suture, followed by hemostasis using a double patch sealing method (DPS) by which the tear was doubly sealed with large and small bovine pericardium patches to which GRF glue was applied. Case 2 with the oozing type of LVFWR was treated only using DPS. Complete hemostasis was achieved in both cases, and aneurysmal dilatation or constrictive heart failure were not detected by postoperative left ventriculography. Therefore, DPS may be useful for treating LVFWR following AMI. 相似文献
10.
来自不同疟疾疫区——长沙、上海、郑州、武汉四地区的中华按蚊,分别以羊膜饲血法感染湖南慈利或湖北沔阳两地区的间日疟原虫,交叉对比其易感性。七次实验共解剖饲血蚊541只。实验结果显示:以腺感染率和阳性腺指数为主要指标,四地区中华按蚊对间日疟原虫的易感性基本相似:两地区间日疟原虫对中华按蚊的感染力也大致相同。并讨论了可能影响人工感染率的几个因素。 相似文献