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101.
应用免疫细胞化学技术及酶联免疫吸附试验(ELISA)对大鼠腹腔肥大细胞合成和释放肿瘤坏死因子(TNF)的状况进行了观测。结果:新鲜分离纯化的大鼠腹腔肥大细胞胞浆呈TNF蛋白阳性。单纯肥大细胞培养早期(2~4 h),上清液中未能检测到TNF,随着培养时间延长,上清液中TNF含量增多;盐酸吗啡与肥大细胞共同培养2h时,上清液中出现可测TNF。四甲基偶氮唑盐(MTT)比色分析试验表明,肥大细胞培养上清液具体有TNF的抗肿瘤活性中。提示:大鼠腹腔肥大细胞能合成和释放TNF,盐酸吗啡能促进肥大细胞释放TNF。  相似文献   
102.
本文在分析黑龙江省妇幼保健机构设置现状的基础上,论述了在社会主义市场经济新形势下,妇幼保健机构发展的指导思想、模式与对策。  相似文献   
103.
T Wu 《中华医学杂志》1990,70(2):72-6, 6
At extreme altitude of 5,620 m, cardiac function was examined with electrical impedance at rest and during exercise. Mountaineers as subjects of experiment were divided into two groups: 15 subjects were Tibetan natives, and 10 subjects were Han visitors of expedition (both were young healthy males). The results showed that no significant difference was seen between the two groups in cardiac pump function at rest. In the Han visitors during exercise, HR increase was restricted, SV and CO were decreased, and PEP/LVET ratio was increased. In the Tibetan natives, HR increased gradually with increased work load, SV tended to be stable CO increased significantly under higher work load, and PEP/LVET ratio decreased gradually. These results suggest that the Tibetan natives were adapted to hypoxic environment much better than the immigrants because their cardiac reserve capacity and maximal oxygen uptake were better than the immigrants at extreme altitude.  相似文献   
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BACKGROUND: Hepatocellular carcinoma (HCC) is one of the most prevalent fatal cancers in the world. Despite advances in early diagnosis and improvements in surgical techniques, the survival of patients with HCC even after resection is poor because of the high incidence of recurrences. Therefore, the identification of prognostic factors may be helpful in the development of new treatment protocols. AIMS: To investigate HER-2/neu status in HCC by immunohistochemistry (IHC) and fluorescence in situ hybridisation (FISH), and to explore the possibility of using trastuzumab in the treatment of HCC. METH ODS: Eight hundred and sixty eight surgical samples from patients with primary HCC were examined for their HER-2/neu status. IHC for HER-2/neu was performed with the HercepTest kit; FISH analysis was performed with the PathVysion HER-2 DNA probe kit. The correlations between HER-2/neu overexpression and clinicopathological characteristics were analysed statistically. RESULTS: HER-2/neu overexpression was detected in 21 (2.42%) of the 868 primary HCCs. Only one specimen showed HER-2/neu gene amplification by FISH. No significant associations were found between HER-2/neu overexpression and the clinicopathological parameters. CONCLUSIONS: There is a low frequency of HER-2/neu overexpression/amplification in HCC. There appears to be no role for HER-2/neu as a prognostic marker and no benefit of anti-HER-2/neu trastuzumab treatment in patients with HCC.  相似文献   
107.
The efficient and non-toxic nuclear delivery of steric-block oligonucleotides (ON) is a prerequisite for therapeutic strategies involving splice correction or exon skipping. Cationic cell penetrating peptides (CPPs) have given rise to much interest for the intracellular delivery of biomolecules, but their efficiency in promoting cytoplasmic or nuclear delivery of oligonucleotides has been hampered by endocytic sequestration and subsequent degradation of most internalized material in endocytic compartments. In the present study, we compared the splice correction activity of three different CPPs conjugated to PMO(705), a steric-block ON targeted against the mutated splicing site of human beta-globin pre-mRNA in the HeLa pLuc705 splice correction model. In contrast to Tat48-60 (Tat) and oligoarginine (R(9)F(2)) PMO(705) conjugates, the 6-aminohexanoic-spaced oligoarginine (R-Ahx-R)(4)-PMO(705) conjugate was able to promote an efficient splice correction in the absence of endosomolytic agents. Our mechanistic investigations about its uptake mechanisms lead to the conclusion that these three vectors are internalized using the same endocytic route involving proteoglycans, but that the (R-Ahx-R)(4)-PMO(705) conjugate has the unique ability to escape from lysosomial fate and to access to the nuclear compartment. This vector, which has displays an extremely low cytotoxicity, the ability to function without chloroquine adjunction and in the presence of serum proteins. It thus offers a promising lead for the development of vectors able to enhance the delivery of therapeutic steric-block ON in clinically relevant models.  相似文献   
108.
OBJECTIVES: 1) To assess, with a peripheral magnetic resonance imaging system (pMRI), the prevalence of bony and soft tissue abnormalities in the knee joints of normal subjects, osteoarthritis (OA) patients, and individuals who have suffered an anterior cruciate ligament (ACL) rupture; and 2) to compare the prevalence among groups. METHODS: Magnetic resonance (MR) images of 28 healthy, 32 OA, and 26 ACL damaged knees were acquired with a 1.0-T pMRI system. Two radiologists graded the presence and severity of 9 MR image features: cartilage degeneration, osteophytes, subchondral cyst, bone marrow edema, meniscal abnormality, ligament integrity, loose bodies, popliteal cysts, and joint effusion. RESULTS: Ten of 28 healthy (35.7%), 24 of 26 ACL (92.3%), and all OA knees (100%) showed prevalent cartilage defects; 5 healthy (17.9%), 20 ACL (76.9%), and all OA knees (100%) had osteophytes; and 9 normal (32.1%), 21 ACL (80.8%), and 29 OA knees (90.6%) had meniscal abnormalities. One-half of the knees in the OA group (16 of 32, 50%) had subchondral cysts, and almost one-half had bone marrow edema (15 of 32, 46.9%). These features were not common in the ACL group (7.7%, and 11.5%, respectively) and were not observed in healthy knees. The OA group had the most severe cartilage defects, osteophytes, bone marrow edema, subchondral cysts, and meniscal abnormalities; the ACL group showed more severe cartilage defects, osteophytes, and meniscal abnormalities than did normal subjects. CONCLUSION: The results suggest that knees that have sustained ACL damage have OA-like reatures; most subjects (19 of 26, 73.1%) could be identified as in the early stage of OA. The prominent abnormalities present in ACL-damaged knees are cartilage defects, osteophytes, and meniscal abnormalities.  相似文献   
109.
Objective To study the protective effects of adenovirus-mediated human beta-nerve growth factor gene (hNGFβ) transfer combined with iron fortified nutrition on blast hearing damage in guinea pigs. Methods Deafness was induced by blast (172dB SPL) in 35 healthy guinea pigs. Seven days after noise exposure, 10 guinea pigs were inoculated with adenovirus-mediated hNGFβ (Ad-hNGFβ) into the perilymphatic space (the gene group), another 10 guinea pigs were given hNGFβ combined with iron fortified nutritional diet (the combination group), still another 10 guinea pigs were inoculated with artificial perilymphatic fluid (APF), and 5 guinea pigs served as control, given neither medicine nor noise exposure. Auditory brainstem response (ABR) threshold shifts were monitored in the guinea pigs before blast exposure and after gene transfer. Changes in cochlear morphology were examined with immunohistochemical and HE staining. Results One week after successful inoculation of hNGFβ, it was noted that Ad-hNGFβ protein was expressed in each turn of the cochlea, and its intensity was almost equal. After gene transfer in the combination group and the gene group, ABR threshold shifts at week 1 and 4 were significantly smaller than those of the APF group. HE staining showed that the number of the spiral ganglion cells in the combination group and the Ad-hNGFβ group was significantly higher than that of the control group after 4 weeks (P<0.01). Conclusions Ad-hNGFβ combined with iron fortified nutritional diet was effective in the prevention and treatment of blast hearing damage of cochlear hair cells.  相似文献   
110.
目的 评价开放复位可塑形钛板内固定治疗跟骨骨折的疗效。方法 对33例(37足)以后关节突移位为主的跟骨骨折,行跟骨外侧入路、开放性复位可塑形钛板螺钉内固定,必要时行植骨术(18例)。结果 平均随访11.5个月,参照Mary—land food score评分,对患足是否疼痛、步态、距下关节及踝关节活动度、是否支架辅助、术后X线摄片等加以评估,19足疗效为优,17足为良,1足可。其中钛板断裂1例,手术切口皮缘坏死1例,换药后自愈。结论 跟骨外侧入路开放复位可塑形钛板螺钉内固定,必要时植骨术是治疗跟骨骨折的有效方法。  相似文献   
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