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排序方式: 共有663条查询结果,搜索用时 15 毫秒
51.
The management of stage I--II Hodgkin's disease with irradiation alone or combined modality therapy: the Stanford experience 总被引:1,自引:0,他引:1
At Stanford University, between 1968 and 1978, 230 patients with pathologic stage I--II Hodgkin's disease were treated on prospective clinical trials with either irradiation alone or irradiation followed by 6 cycles of adjuvant combination chemotherapy. The actuarial survival at 10 yr was 84% for patients in either treatment group. Freedom from relapse at 10 yr was 77% among patients treated with irradiation alone and 84% after treatment with combined modality therapy [p(Gehan) = 0.09]. Freedom from second relapse at 10 yr was 89% and 94%, respectively [p(Gehan) = 0.56]. Several prognostic factors were evaluated in order to identify patients at high risk for relapse or with poor ultimate survival after initial treatment with irradiation alone. Systemic symptoms, histologic subtype, age, and limited extranodal involvement (E-lesions) did not affect the prognosis of patients and failed to identify patients whose survival could be improved by the routine use of combined modality therapy. Patients with large mediastinal masses (mediastinal mass ratio greater than or equal to 1/3) had a significantly poorer freedom from relapse when treated with irradiation alone than when treated initially with combined modality therapy [45% versus 81% at 10 yr, p(Gehan) = 0.03). The 10-yr survival of these patients, however, was not significantly different (84% versus 74%). The implications of these observations on the management of patient with early stage Hodgkin's disease are discussed. 相似文献
52.
7β-(6-取代-2-喹诺酮-3-乙酰氨基)头孢菌素的合成 总被引:1,自引:0,他引:1
以6-取代-2-喹诺酮-3-乙酸为侧链,用CDI法和潘化酯法与7-ADCA,7-ACA,7-ACT,和7-ACD缩合,合成了16个新的7β-(6-取代-2-喹诺酮-3-乙酰氨基)头孢菌素类化合物,通过溶媒转提,葡聚糖凝胶(Sephadex LH-20)柱层析及离心薄层层析分离精制,得到纯品。初步体外抑菌试验表明:新化合物对革兰氏阳性及某些阴性菌具有高度敏感性。大多数化合物对所试试验菌的抗菌活性与头孢唑啉和青霉素G钠相当,有些比它们还强。 相似文献
53.
Cloning and expression of the gene involved in Sanfilippo B syndrome (mucopolysaccharidosis III B) 总被引:4,自引:1,他引:4
Sanfilippo B syndrome is caused by a deficiency of alpha-N-
acetylglucosaminidase, a lysosomal enzyme involved in the degradation of
heparan sulphate. Accumulation of the substrate in lysosomes results in
degeneration of the central nervous system with progressive dementia often
combined with hyperactivity and aggressive behaviour. In order to clone the
deficient gene, we purified the enzyme from human placenta and obtained
amino acid sequence information. Alignment of one of the CNBr generated
internal peptides to sequence from the database revealed the chromosomal
location of the gene in the 5' upstream flanking region of the gene for
17-beta-hydroxysteroid-dehydrogenase at 17q21.1. The available DNA sequence
was used to clone the cDNA coding for alpha-N- acetylglucosaminidase and
analyse its gene structure. The gene is fully contained in the 5' upstream
flanking region of the gene for 17-beta- hydroxysteroid-dehydrogenase and
interrupted by five introns. The cDNA clone has a length of 2575 bp and
encodes a protein of 743 amino acids. Chinese hamster ovary cells
transfected with the cDNA construct show alpha-N-acetylglucosaminidase
activity about 17-fold over background. This will allow correction studies
with NAG deficient Sanfilippo B cell lines and facilitate the development
of enzyme replacement therapy for these patients.
相似文献
54.
55.
Ming Zhao Yan‐Fang Xian Siu‐Po Ip Harry HS Fong Chun‐Tao Che 《Phytotherapy research : PTR》2010,24(9):1414-1416
A new protoberberine alkaloid, 3‐hydroxy‐2‐methoxy‐9,10‐methylenedioxy‐8‐oxo‐protoberberine, along with three known compounds, was isolated from Rhizoma Coptidis. The new compound displayed weak antispasmodic activity against acetylcholine‐induced contraction in isolated guinea‐pig ileum with an IC50 of 83.7 μm . Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
56.
颈动脉血管重构特征在自发性高血压大鼠体内的表现 总被引:2,自引:0,他引:2
目的:血管重构是高血压的重要病理变化,是高血压导致器官损害的结构基础。实验观察自发性高血压大鼠颈动脉中层组织学的相关变化,以验证血管重构的特点。方法:实验于2006-06/2007-03在福建医科大学附属协和医院心血管内科实验室完成。①实验材料及分组:12周龄雄性自发性高血压大鼠10只,同性别周龄的WKY大鼠10只为对照,喂养18周后终止实验。②实验过程及评估:开始及每2周测鼠尾收缩压。实验结束后,麻醉后取颈动脉,行苏木精-伊红、苦味酸-天狼星红、弹力纤维和胶原纤维的双重染色(P/VB法),利用计算机辅助成像系统测算颈动脉中膜厚度、腔径、血管中膜厚/腔径、中膜横截面积、中膜细胞平均核面积及中膜的胶原面积百分比、弹性纤维面积百分比、弹性纤维面积与胶原面积的比值。SP免疫组织化学染色检测α-平滑肌肌动蛋白、增殖细胞核抗原、纤维粘连蛋白、层粘连蛋白等抗原在颈动脉壁的表达,并计算颈动脉中膜细胞增殖指数;以原位末端标记法标记血管壁的凋亡细胞,计算颈动脉中膜细胞凋亡指数。结果:20只大鼠全部进入结果分析。①自发性高血压大鼠实验开始和结束前的收缩压均>150mmHg,高于WKY大鼠(P<0.01)。②自发性高血压大鼠颈动脉中膜厚度、腔径、中膜厚度/腔径、中膜横截面积、中膜胶原面积百分比均高于WKY大鼠(P<0.01),而中膜弹性纤维面积百分比、弹性纤维面积与胶原面积比值均低于WKY大鼠(P<0.01)。③α-平滑肌肌动蛋白在两组大鼠颈动脉中膜均可表达,提示中膜细胞为血管平滑肌细胞。④自发性高血压大鼠中膜血管平滑肌细胞平均核面积大于WKY大鼠(P<0.01),中膜细胞增殖指数与WKY大鼠差异无显著性(P>0.05),中膜细胞凋亡指数显著低于WKY大鼠(P<0.01)。⑤自发性高血压大鼠颈动脉中膜纤维粘连蛋白、层粘连蛋白的光密度值(IA值)及染色阳性面积百分比高于WKY大鼠(P<0.01)。⑥颈动脉中膜血管平滑肌细胞凋亡指数与中膜横截面积呈显著负相关(r=-0.872,P<0.01);纤维连接蛋白表达的吸光度值与中膜横截面积呈显著正相关(r=0.954,P<0.01)。结论:自发性高血压大鼠颈动脉存在明显的重构,其特点为中膜肥厚、平滑肌细胞肥大、凋亡减少及胶原、纤维粘连蛋白、层粘连蛋白的过度沉积。 相似文献
57.
Po‐Lin Tseng Jing‐Houng Wang Hung‐Da Tung Chao‐Hung Hung Kwong‐Ming Kee Chien‐Hung Chen Kuo‐Chin Chang Chuan‐Mo Lee Chi‐Sin Changchien Pao‐Fei Chen Lin‐San Tsai Sheng‐Nan Lu 《Journal of gastroenterology and hepatology》2010,25(8):1426-1434
Background and Aim: The early detection of hepatocellular carcinoma (HCC) and opportunity to select appropriate treatment are important benefits of HCC screening. Our aim in the present study was to investigate the survival rate, prognostic factors and treatment effects in HCC patients of community‐based screening. Methods: Community‐based ultrasound (US) screening for HCC in adults with platelet counts (< 150 × 103/mm3) and/or alpha fetoprotein (AFP) > 20 ng/mL was conducted in 2002 and 2004. As per the Barcelona Clinic Liver Cancer (BCLC) stage, 90 cases of intermediate or earlier stage HCC were detected and 88 cases had sufficient information for analysis (49 men and 39 women, aged 65.8 ± 9.6 years). The tumor diameter was mostly less than 5 cm (76.1%). The follow up was continued until June 2008. Results: The 4‐year overall survival rate was 46.8%. Old age (≥ 70 years) (P = 0.046), later stage of HCC (intermediate vs earlier) (P = 0.012), low platelet count (< 100 × 103/mm3) (P = 0.013) and refusal of modern treatment (P = 0.026) were independent poor prognostic factors. Curative treatment increased survival in patients of all ages. Both curative treatment and transcatheter arterial embolization (TAE) increased survival in cases of intermediate HCC. However, treatment benefits were not found for patients with (very) early stage HCC. Conclusions: Early detection and prompt treatment of HCC leads to increased survival. For elderly patients this benefit was seen only for early stage cases receiving curative treatment. Differences between treatment types for patients with (very) early stage HCC might emerge with a longer follow‐up period. 相似文献
58.
Kwong‐Ming Kee Chi‐Ming Hung Jing‐Houng Wang Chao‐Hung Hung Pao‐Fei Chen Kuo‐Sin Lin Sheng‐Nan Lu 《Journal of gastroenterology and hepatology》2010,25(7):1289-1294
Background and Aim: This study attempted to clarify accuracy of acute hepatitis C (AHC) and its clinical characteristics. Methods: We reviewed 632 reported cases from national surveillance data of the Taiwan Center for Disease Control between 1995 and 2004, and reclassified diagnoses. A definite case was defined as alanine aminotransferase (ALT) > 10 × the upper limit of normal (ULN) with seroconversion of anti‐hepatitis C virus antibody (anti‐HCV). A probable case was defined as (i) seroconversion of anti‐HCV and/or elevated ALT levels; or (ii) anti‐HCV(+) but titers increased (from < 40 S/CO to ≥ 40 S/CO) and ALT > 10 × the ULN. A suspected case was defined as initial anti‐HCV(+) and ALT level > 10 × the ULN and/or jaundice. Excluded cases were defined as ALT levels less than 10 × ULN with initial positive anti‐HCV Ab. Results: A total of 310 (49%) cases were confirmed as AHC; these included 95 (15%) definite and 215 (34%) probable cases. Higher incidence rates and accuracy of AHC were demonstrated in the southern area significantly if compared with northern, eastern and central areas, respectively (all P < 0.05). On comparison between blood centers and hospitals, more AHC cases were found in Southern Taiwan than in other areas (157/73 vs 24/40, P < 0.001), younger mean age (33.3 ± 11.1 vs 49.3 ± 16.4, P < 0.001), lower ALT levels (263.1 ± 200.9 vs 1264.2 ± 706.8, P < 0.001) and male predominance (191/39 vs 46/18, P = 0.046). Conclusions: This study showed our reporting system over‐estimated the AHC diagnosis, which is also a common issue worldwide. Greater efforts are needed to establish appropriate reporting systems, as well as more supplemental methods to distinguish between prevalent and incident cases. 相似文献
59.
Background: Calcium channel blockers potentiate the effects of local anaesthetics. We examined the effect of adding verapamil to local anaesthetic solution on anaesthetic duration in patients undergoing surgery under brachial plexus block. 相似文献
60.