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61.
MMP-9和TIMP-1表达失衡与乳腺癌浸润、转移的相关性 总被引:2,自引:0,他引:2
目的 研究乳腺癌组织中基质金属蛋白酶(MMP-9)和金属蛋白酶组织抑制因子(TIMP-1)的表达变化与乳腺癌生物学行为及淋巴结转移的关系。方法 应用SP免疫组织化学方法检测85例乳腺癌组织MMP-9,TIMP-1及细胞增殖核抗原ki-67的表达情况。结果 MMP-9阳性染色率90.59%,MMP-9阳性表达与肿瘤浸润,淋巴结转移,ki-67指数及TNM分期呈正相关(Pearson列联系数分别为P=0.03,P=0.02,P=0.004和P=0.0000,P<0.05,0.01。TIMP-1阳性染色率为78.82%,TIMP-1阳性表达与肿瘤浸润,淋巴结转移及TNM分期浸润,转移及ki-67指数显著相关(P<0.05,P<0.01,P<0.001)。结论 MMP-9和TIMP-1表达失衡与乳腺癌浸润及淋巴结转移密切相关。 相似文献
62.
目的为抑制脑血栓形成,合成与TF基因启动子区切应力反应元件(SSRE)形成三链DNA的硫代磷酸酯寡核苷酸(TFO)。方法设计TFO序列14条,采用固相亚磷酰胺三酯固相法合成TFO。硫代磷酸酯修饰在TFO的3'末端进行。应用电泳迁移分析(EMSA)观察寡核苷酸和硫代脱氧寡核苷酸的亲和性。结果在设计合成的14条寡核苷酸中,与靶序列能形成三链DNA的TFO只有T21GTa、T14GTa和T15GTa,其Kd值分别为3.6×10-10、1.0×10-9和1.0×10-8(M),经硫代磷酸酯修饰后分别为:2.3×10-9、3.8×10-9和1.5×10-8。结论硫代磷酸酯修饰的T21GTa-ps、T14GTa-ps和T15GTa-ps能够与TF基因启动子SSRE的3个位点形成三链DNA。 相似文献
63.
R. L. Mittal 《International orthopaedics》1987,11(3):189-192
Summary Resistant club foot remains an unsolved problem because of the complex aetiological and pathological factors, and is still seen quite frequently, especially in developing countries. The posteromedial skin contracture is a potent deforming force which is responsible for many failures or relapses. I report the results of an operation in which a rotation skin flap was combined with an extensive soft-tissue release. The age of the children was from 9 months to 10 years. The follow-up period was from one to 9 years with an average of 43 months, and in 50 cases for more than 5 years. I consider that the outcome has been excellent or good in 94 out of 100 feet.
Résumé Le pied bot invétéré demeure un problème mal résolu en raison de la complexité des facteurs étiologiques et anatomiques et il est encore bien souvent rencontré, notamment dans les pays en voie de développement. La rétraction cutanée postéro-interne représente un puissant élément de la déformation, qui est responsable de bon nombre d'échecs ou de récidives. Nous rapportons les résultats d'une opération qui associe un lambeau cutané de rotation à la libération des parties molles. L'âge des enfants était compris entre neuf mois et dix ans. Le recul est de un à neuf ans, avec une moyenne de 43 mois. Cinquante enfants ont été suivis plus de cinq ans. Les résultats sont excellents ou bons dans 94% des cas.相似文献
64.
In order to further investigate the effect of annexin Ⅱ (Ann- Ⅱ ) on tissue plasminogen activator (t-PA)-dependent plasminogen (PLG) activation and its interactive mechanism, recombinant native Ann- Ⅱ bound t-PA, PLG and plasmin with high affinity was examined. The flow cytometric assay showed that the ann- Ⅱ expression rate was higher in the human umbilical vein endothelial cell (HUVEC) (87. 65 %) than in the HL-60 cells as controls (35. 79 %). Two irrelevant proteins,bovine serum albumin (BSA) and equine IgG (EIG) had no effect on the production of plasmin.Ann- Ⅱ -mediated enhancement of t-PA-dependent PLG activation was inhibited by ε-aminocaproic acid or by pretreatment of Ann- Ⅱ with carboxypeptidase B with the inhibitive rate being 77.8 % and 77. 0 %, respectively. It was revealed that the effect of Ann- Ⅱ on PLG activation was specific for tPA. Urokinase didn‘t bind to Ann- Ⅱ , demonstrating the role of receptor-related lysine residues on activation of PLG, showing that the Ann- Ⅱ -PLG interaction was dependent upon carboxyl-terminal lysine residues. These findings suggest that annexin Ⅱ -mediated co-assembly of t-PA and PLG may promote plasmin generation and play a key role in modulating fibrinolysis on the endothelial surface. 相似文献
65.
Breast cancer is the female malignant neoplasia with the highest incidence in the industrialized world. Despite many undeniable therapeutic successes obtained, breast cancer still remains, however, a major health issue. In the last few years, thanks to aromatase inhibitors, the hormone therapy for oestrogen-dependent breast cancer has evolved in terms of efficacy and tolerability; at the same time, it has enabled us to better define the role of oestrogens in the etiopathogenesis of this tumour. Weight increase and obesity have been identified as the most important risk and prognostic factors for breast cancer in postmenopausal women. Several hypotheses have been proposed to explain the association of obesity with postmenopausal breast cancer. A more recent hypothesis suggests that adipocytes and their autocrine (paracrine and endocrine actions) are at the centre of such an etiopathogenetic mechanism. A better understanding of the main mechanisms that link together menopause, body-weight increase and hormone-dependent breast cancer is paramount to enable the identification of key molecules involved in the development of breast carcinoma and suggest new therapeutic options. The present review will discuss important findings on the therapeutic aspects of adipose tissue and adipokines as a target for treatment of hormone-dependent breast cancer. 相似文献
66.
67.
目的 观察卡铂碳包铁纳米笼壳聚糖微球 ( carboplatin-Fe@C-loaded chitosan nanoparticles , C - Fe@C-CN )结合磁场在移植性肝癌大鼠模型体内的靶向分布情况和药动学过程。 方法 建立移植性肝癌大鼠模型 40 只为 A 组, 正中开腹行肝动脉插管,按卡铂 5 mg·kg-1 体重注入 C-Fe@C-CN 的生理盐水分散液,以肿瘤组织为靶区施加 0.5 T 磁场 30 min 。分别在给药后 0.25 , 0.5 , 1 , 3 , 6 , 12 , 24 和 48 h 各时间点,每组取 5 只大鼠处死,采集血浆、靶区肿瘤、非靶区肝、肾、脾和肺组织标本,石墨炉原子分光光度计测定血浆和组织中卡铂浓度,药物浓度数据用 3P87 药动学程序分析处理,并组织学 观察 C-Fe@C-CN 的在各脏器分布情况。 另 40 只健康大鼠为 B 组,以左肝叶为靶区,给予相同的处理作为对照。 结果 A 组靶区肿瘤组织 <> c max 是 65.21 μg·g-1 ,为 B 组靶区肝组织( 38.47 μg·g-1 )的 1.7 倍。 48 h 时 A 组靶区肿瘤组织药物浓度是 7.27 μg·g-1 ,为 B 组靶区肝组织( 3.11 μg·g-1 )的 2.3 倍。 A 组靶区肿瘤组织 AUC 是 906 mg·h·L-1 ,为 B 组靶区肝组织( 421.34 mg·h·L-1 )的 2.2 倍。 2 组药动学参数值相近。病理学观察 显示, C-Fe@C-CN 在磁场作用下聚集于肿瘤细胞间隙中,并可栓塞于部分细小动脉。非靶区肝组织内少见 C-Fe@C-CN 的聚集和栓塞的血管。 结论 C-Fe@C-CN 在体内具有长循环和缓释特性,在磁场的引导下对肿瘤组织具有更强的靶向性,成倍提高肿瘤组织中的药物浓度,延长维持时间。 相似文献
68.
Necrotizing soft tissue infections (NSTI) represent a spectrum of diseases characterized by extensive rapidly progressive necrosis that may involve the skin, subcutaneous tissues, fascia or muscle. Their progress is extremely fast, leading often to sepsis and septic shock that ends up in multiple organ failure with abrupt and high mortality. A variety of classification systems have been developed based on parameters such as anatomic location of the disease or microbiology. There are a number of factors that predispose to the spread of these soft tissue infections, such as delays in recognition, immune suppression, diabetes mellitus and advanced age. The use of broad‐spectrum antibiotics tends to mask the severity of the underlying infection, modulates the clinical presentation, and even delays hospital admission. The most important factor affecting outcome in NSTI is early diagnosis and aggressive radical surgical treatment. The medical records of 13 patients who had been treated for NSTI from 1996 to 2005 were reviewed, retrospectively. There were eight men (61.5%) and five (38.5%) women. Mean age was 56 years (range 27–73). Seven cases of infection involved the perineal region (54%), two the lower limb, one the upper limb and three the abdominal wall/trunk. The most common associated comorbidity was diabetes mellitus in five patients (38.5%). A single organism was identified in two (15%) and multiple organisms in 11 (85%) patients. Necrotizing aponeurositis Type I was the most common of the polymicrobial necrotizing infections. Overall survival was 85%, and the mean hospital stay for survivors was 35 days (range 17–92). 相似文献
69.
Sutureless bowel anastomosis using Nd:YAG laser 总被引:5,自引:0,他引:5
Small bowel anastomoses were performed without sutures by using the Nd:YAG laser to produce welded enterotomies. Optimal energy levels for contact and noncontact laser were determined. Anastomoses produced using five target energy levels between 100 and 500 J were examined. Short-term anastomotic strength of these enterotomies was measured 1 min after the welding. Bursting pressure of the laser welded enterotomies was compared to the bursting pressure of traditional two-layer, inverting, interrupted sutured bowel anastomoses. The overall mean bursting pressure of non-contact-welded enterotomies was 50.6 mmHg. Optimal laser settings determined in this initial phase were then used to produce anastomoses in rabbits which are recovered postoperatively for 1 or 2 weeks in order to examine long-term viability and integrity of the anastomoses. All chronic rabbit preparations recovered without complication. The mean bursting pressure was 200 mmHg, not significantly different from that of uncut bowel or two-layer sutured anastomosis. 相似文献
70.
P Schuff-Werner E Schütz W C Seyde T Eisenhauer G Janning V W Armstrong D Seidel 《European journal of clinical investigation》1989,19(1):30-37
Heparin-induced Extracorporeal LDL-Precipitation (HELP) is an effective procedure for the elimination of both plasma LDL and fibrinogen. In 10 adult patients with severe type II hyperlipoproteinemia, a single HELP treatment of 3 1 plasma led to an acute decrease in the average plasma viscosity (PV) from 1.30 to 1.1 mPas. At the same time, an even more marked decrease in the mean erythrocyte aggregation rate from a pathological value of 7.9% to a value of 3.7% (normal range less than 5%) was observed. Long-term studies on five patients demonstrated a lasting improvement in these two haemorheological variables. The acute rheological changes were also accompanied by an improvement in polarographically determined muscle oxygen tension. Mean oxygen tension values measured in both the m.biceps brachii and the m.tibialis anterior in five patients before and after a single HELP treatment increased from 30 +/- 4 to 37 +/- 7 mmHg and from 27 +/- 2 to 31 +/- 3 mmHg respectively. These results may provide an explanation for the rapid improvement in patients' clinical symptoms such as angina pectoris and in stress electrocardiogram which have been observed during HELP therapy. 相似文献