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31.
Optical nano-imaging for the diagnosis of gastrointestinal cancers]   总被引:1,自引:0,他引:1  
Development of in vivo animal imaging instrumentations and methods contributes to the early diagnosis of cancer. Of variable imaging modalities, in vivo optical imaging such as bioluminescence and fluorescence is one of the best methods to measure molecular change of cancer cells. High sensitivity and relatively low cost of optical method gives benefits to apply for translational research in the field of cancer. Nano-probes to label and detect early cancer cells have been developed by nano-chemists and molecular imaging researchers. Quantum dots made from fluorescent semi-conductors show good advantages in term of imaging probes; high quantum yields, large molar extinction coefficients, size-dependent tunable emission and high photostability. To detect a gastrointestinal (GI) cancer, newly developed endoscopes have been used. Among them, near infrared fluorescence endoscope and confocal endomicroscope are good candidates for clinical application. In animal studies, successful results to detect cancer in gastrointestinal tract have been obtained. Prospect of nanoparticles as optical imaging moiety is promising to detect GI cancers if their toxicity is minimized. Future fluorescence confocal endoscope with safe cancer targeting nanoparticles will be useful for the detection and treatment of GI cancers.  相似文献   
32.
We report an uncommon case of solitary, small hepatic angiosarcoma that was initially considered as a hemangioma. We present the imaging findings, with an emphasis on the initial and follow-up CT and MR findings, as well as report on the more suggestive findings of angiosarcoma than those of a hemangioma.  相似文献   
33.
BACKGROUND: To adequately address the complex health needs of young people, their access to services, and the quality of services received, must be improved. AIMS: To explore the barriers to service provision for young people and to identify the training needs of primary healthcare service providers in New South Wales (NSW), Australia. DESIGN OF STUDY: A cross-sectional, qualitative study of the perspectives of a range of health service providers. SETTING: A range of primary healthcare organisations across NSW. METHODS: Samples of general practitioners (GPs), youth health workers, youth health coordinators, and community health centre staff were drawn from urban and rural clusters across NSW. Focus groups and interviews were used to identify barriers to service provision and the training needs of service providers. Data were tape recorded, transcribed, and analysed. RESULTS: Barriers to service provision among GPs and community health centre staff included inadequate time, flexibility, skills, and confidence in working with young people, and poor linkages with other relevant services. Training needs included better knowledge of and skills in adolescent health requirements, working with adolescents, and working with other services. Barriers to service provision for youth health workers and coordinators included lack of financial resources and infrastructure. There were few linkages between groups of service providers. CONCLUSION: Models of service provision that allow stronger linkages between service providers, sufficient time for consultation with young people, adequate training and support of health professionals, and flexibility of service provision, including outreach, should be explored and evaluated.  相似文献   
34.
目的观察由黄芪、白术、淫羊藿组成的复方制剂(壮骨肾宝)对实验性小鼠高脂血症的影响。方法用蛋黄乳液快速致小鼠单纯性高胆固醇血症和喂养高脂饲料致高脂血症模型 ,观察预防性给予不同剂量的壮骨肾宝后对血清总胆固醇(TC)、甘油三酯(TG)和高密度脂蛋白胆固醇(HDL -ch)的影响。结果壮骨肾宝中、高剂量能使血清TC降低(P<0.05),HDL -ch升高(P<0.01) ,但对TG的影响不大。结论壮骨肾宝有一定降血脂作用 ,并与剂量有关  相似文献   
35.
Eight cases of malignant and 12 0f benign Bren- ner tumor are reported, patient ages ranged 31 69 and 39-53 years. The malignant tumor was bilateral in 6 0f 8 cases, and the benign in l of 12. The greatest diameter of the malignant tumors averaged around 11 cm, and the benign 10. Six of the malignant Brenner tumor patients died, one was lost to follow up, and one survived for 10 years. Pathologic and microscopic findings were pre- sented in some detail. Based on the analysis of the association between the histologic features and type of Mullerian epithelium, we believe that the so called Brenner tumor is in effect a tumor arising from the Mullerian epithelium with a tendency to differentiate into vaginocervical type epithelium.  相似文献   
36.
介入手术治疗异位妊娠12例临床分析   总被引:1,自引:0,他引:1  
目的:探索一种治疗输卵管妊娠的微创介入手术,解决因其腹腔出血不能接受保守治疗或保守治疗失败的难题。保持输卵管完整及通畅,满足有生育需求的患。方法:对12例输卵管妊娠妇女行对侧股动脉穿刺,将导管超选择插至子宫动脉以甲氨喋呤(MTX)进行灌注及明胶海绵栓塞术。结果:本组病例中,术后10dB超复查孕囊脱落、吸收消失,栓塞后盆腔活动性出血停止。结论:介入治疗宫外孕输卵管妊娠,能有效杀灭胚胎组织,栓塞破裂血管止血效果明显,且能保持输卵管通畅。  相似文献   
37.
38.
We present a case of benign osteoblastoma of the occipital bone. Benign osteoblastoma is an uncommon primary bone tumor, which usually involves the vertebrae and the long bones. This tumor rarely develops in the calvaria, showing a preference for the temporal and frontal bones when it does. To the best of our knowledge, this case is only the eighth reported case of benign osteoblastoma confined to the occipital bone. A 20‐year‐old male presented with a mild tender mass lesion of the occipital area, just below the lambda. Plain X‐ray films and CT scans demonstrated an osteolytic mass surrounded by the sclerotic rim within the diploic space. MRI proved to be effective for the evaluation of the intracranial and intraosseous extensions of the tumor. However, it was very difficult to formulate a differential diagnosis against other osteoblastic tumors, or osteoid osteoma, in view of its radiological appearance. The final diagnosis was obtained by careful consideration of the histopathological characteristics of the tumor combined with its clinical and radiological features. Although generally regarded as benign, a complete resection is preferred over conventional curettage as this can guard against possible recurrence and malignant transformation.  相似文献   
39.
采用两株分别带有不同抗药性标记的产黄青霉原生质体以1:1相混合,用30%的聚乙二醇(MW6000)原生质体融合处理。将混和物涂布在补给有两种药物同时存在的高渗性分离培养基上,培养后获得异核体菌落。洗下异核体分生孢于继续分离在补给有两种药物同时存在的分离培养基上,得到了同时带有两种抗性标记的重组体。纯化后,进行抗性稳定性和摇瓶效价的测定,将一株具有双重抗性、摇瓶发酵效价较高的菌株作出发菌株,经诱变因子处理后,获得了一株43u7c—57菌株,在摇瓶中效价比生产菌株平均提高4.94%,该菌株在40吨发酵罐试生产后,发酵效价平均提高4.4%,产量则平均增加12.15%。  相似文献   
40.
From the roots ofPulsatilla koreana, three monodesmosides(pulsatilla saponins A, B and D) and two bisdesmosides(pulsatilla saponins F and H) were isolated. The structure of these saponins have been determined as hederagenin 3-O-α-L-rhamnopyranosyl(1→2)-α-L-arabinopyranoside(A), hederagenin 3-O-β-D-glucopyranosyl(1→4)-α-L-arabinopyranoside(B), hederagenin 3-O-α-L-rhamnopyranosyl (1→2)-[β-D-glucopyranosyl(1→4)]-α-L-arabinopyranoside(D), 3-O-α-L-rhamnopyranosyl(1→2)-α-L-arabinopyranosyl hederagenin 28-O-α-L-rhamnopyranosyl(1→4)-β-D-glucopyranosyl(1→6)-β-D-glucopyranosyl ester (F) and 3-O-α-L-rhamnopyranosyl(1→2)-[β-D-glucopyranosyl(1→4)]-α-L-arabinopyranosyl hederagenin 28-O-α-L-rhamnopyranosyl(1→4)-β-D-glucopyranosyl(1→6)-β-D-glucopyranosyl ester(H) on the basis of chemical and spectral studies. Pulsatilla saponin B is the first report of its presence in plants but saponins A, D, F, and H have recently been isolated from the same genusP. cernua.  相似文献   
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