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11.
赵莉  宋文刚 《医学争鸣》2007,28(15):1437-1439
DC-SIGN是DC表面识别多种病原微生物的受体.一方面,DC借助DC-SIGN对固有免疫及适应性免疫发挥免疫调节作用;另一方面,DC-SIGN又成为某些病原微生物如肝炎病毒借以逃逸机体免疫防御功能的靶分子.我们就DC-SIGN的结构及功能、与病毒的相互作用等方面进行阐述.  相似文献   
12.

Background  

Residency training takes place primarily on inpatient wards. In the absence of a resident continuity clinic, internal medicine residents rely on block rotations to learn about continuity of care. Alternate methods to introduce continuity of care are needed.  相似文献   
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The authors present the radiographic features of a previously incompletely delineated bone dysplasia, which they call spondylometaphyseal dysplasia, corner fracture type. This is a dominant heritable condition associated with short stature and developmental coxa vara. The progressive hip deformity usually causes significant disability requiring surgical correction. Developmental coxa vara, simulated corner fractures of long tubular bones, and vertebral body abnormalities result in a diagnostic constellation. Knowledge of these distinctive radiologic features allows accurate diagnosis, which in turn should lead to appropriate genetic counseling and possibly to earlier, more efficacious surgical treatment of the coxa vara.  相似文献   
16.
Three examples of human plasma-derived concentrates, intermediate- purity factors VIII and IX, and fibrinogen were spiked with tissue culture-grown human immunodeficiency virus type 1 (HIV-1) strain RF. All examples were freeze-dried and heated at 80 degrees C for 72 hours by using validated production process models. HIV-1 infectivity was measured by a syncytial infectivity assay in C8166 cells and then compared with levels determined by nested HIV polymerase chain reaction (PCR). The infectivity assay demonstrated a reduction index of at least 4.5 log10, while PCR showed an average 1.7 log10. Large amounts of HIV- 1 RNA (10(5)) were still detectable by PCR in samples in which infectivity assays failed to detect any HIV-1. These data suggest that HIV-1 PCR levels do not parallel HIV-1 infectivity levels during virus- inactivation procedures involved in coagulation factor concentrate production. PCR was able to detect the RNA associated with inactivated HIV-1 particles in the factor concentrates, which allows the conclusion that PCR is not a useful test with which to monitor virus-inactivation procedures such as heating at 80 degrees C for 72 hours. This judgment contrasts with the more definite and sensitive role of PCR in diagnosing HIV-1 infection in patients in whom a positive HIV-1 PCR result correlates with active HIV-1 infection and with PCR's usefulness in monitoring virus removal.  相似文献   
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SUMMARY Clinically significant symptoms due to gastrointestinal metastases from primary lung cancers is rare. A case of life-threatening lower gastrointestinal haemorrhage secondary to metastatic squamous cell carcinoma of the lung is reported. Previous reports of such metastases are reviewed, with reference to management and prognosis. After resection of colonic metastases from squamous cell lung cancer, survival is similar to that for primary disease. It is suggested that patients with known or suspected squamous cell lung cancer presenting with lower gastrointestinal symptoms be managed as aggressively as those with no previous history of disease.  相似文献   
18.

Objectives

To investigate established prognostic factors and relatively new histopathological tumor characteristics including metric substage and lamina propria invasion patterns in a large series of T1 high‐grade non‐muscle‐invasive bladder cancer.

Methods

Between 1989 and 2012, 322 patients with initial stage T1 high‐grade bladder cancer underwent transurethral resection, followed by re‐transurethral resection and a conservative approach with follow‐up regime alone or instillation treatment. Transurethral resection specimens were reassessed by two experienced urological pathologists for tumor grade according to the World Health Organization 1973 classification, metric T1 substage, lamina propria invasion pattern and associated carcinoma in situ. The median follow‐up period was 42 months (interquartile range 25–72 months). In addition to Kaplan–Meier analyses, uni‐ and multivariable Cox regression analyses were used to compare progression‐free survival, cancer‐specific survival and overall survival for the studied parameters comparing two subcohorts.

Results

While in patients after instillation treatment no examined feature was shown as an independent predictor for prognosis, there were predictive histopathological features in multivariable Cox regression analyses in instillation treatment‐naïve patients: associated carcinoma in situ (hazard ratio 2.278, 95% confidence interval 1.119–4.634, P = 0.023) and World Health Organization 1973 grade 3 (hazard ratio 2.950, 95% confidence interval 1.021–8.536, P = 0.046) for worse progression‐free survival, infiltrative lamina propria tumor pattern for worse cancer‐specific survival (hazard ratio 2.369, 95% confidence interval 1.034–5.429, P = 0.042) and overall survival (hazard ratio 1.049, 95% confidence interval 1.024–1.075, P = 0.001).

Conclusions

The results of the present T1 high‐grade bladder cancer series suggest that lamina propria invasion pattern is a promising parameter to predict the prognosis of T1 high‐grade bladder cancer in an instillation treatment‐naïve subcohort. Prospective multicenter evaluations are warranted. The need for instillation treatment in T1 high‐grade bladder cancer is clearly demanded.  相似文献   
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范永卫  杨赤  万玉良  王伟刚  陈素萍 《医学争鸣》2009,30(12):1149-1151
端粒酶与肿瘤发生发展的关系是近年来肿瘤研究领域的热点之一.端粒的磨耗限制大多数体细胞的复制,肿瘤细胞主要通过转录上调端粒酶限制成分催化亚基端粒酶逆转录酶(hTERT)维持端粒长度.由于hTERT启动子区域已被克隆,其特点也已被鉴定,hTERT启动子介导的靶向性肿瘤基因治疗成为研究的热点.我们综述了hTERT启动子介导的靶向性肿瘤基因治疗最新研究进展.  相似文献   
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