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991.
Two new coumarins, named (±)-euryacoumarin A (1) and 6-demethylobtusinin (2), and one new natural coumarin, named euryacoumarin B (3), along with two known compounds, scopoletin (4) and obtusinol (5), were isolated from the stems of Eurya chinensis. Their structures were elucidated by means of extensive spectroscopic methods and comparison with data reported in the literatures. Compound 1 exhibited significant inhibition of LPS-induced nitric oxide (NO) production in RAW264.7 cells with IC50 value of 35.64 ± 1.73 μM, and showed marginal antibacterial activities against Bacillus subtilis and B. cereus with MIC values of 50.59 ± 2.12 and 35.42 ± 0.96 μM, respectively.  相似文献   
992.
目的:确定投入临床使用前标定加速器输出剂量的方法.方法:根据IAEA第277号技术报告光子与电子束吸收剂量测量中的相关内容,将剂量校准中所用到的多个因子简化成用户因子.结果:结合自身经验及应用实例,得出了校准加速器输出剂量的方法及步骤.结论:依照此方法可以快捷地对加速器输出剂量进行测量与校准.  相似文献   
993.
994.
IntroductionA proper cavernous endothelial cell culture system would be advantageous for the study of the pathophysiologic mechanisms involved in endothelial dysfunction and erectile dysfunction (ED).AimTo establish a nonenzymatic technique, which we termed the “Matrigel‐based sprouting endothelial cell culture system,” for the isolation of mouse cavernous endothelial cells (MCECs) and an in vitro model that mimics in vivo situation for diabetes‐induced ED.MethodsFor primary MCEC culture, mouse cavernous tissue was implanted into Matrigel and sprouting cells from the tissue were subcultivated. To establish an in vitro model for diabetes‐induced ED, the primary cultured MCECs were exposed to a normal‐glucose (5 mmoL) or a high‐glucose (30 mmoL) condition for 48 hours.Main Outcome MeasuresThe purity of isolated cells was determined by fluorescence‐activated cell sorting analysis. MCECs incubated under the normal‐ or the high‐glucose condition were used for Western blot, cyclic guanosine monophosphate (cGMP) quantification, and in vitro angiogenesis assay.ResultsWe could consistently isolate high‐purity MCECs (about 97%) with the Matrigel‐based sprouting endothelial cell culture system. MCECs were subcultured up to the fifth passage and no significant changes were noted in endothelial cell morphology or purity. The phosphorylation of Akt and eNOS and the cGMP concentration were significantly lower in MCECs exposed to high glucose than in those exposed to normal glucose. MCECs exposed to the normal‐glucose condition formed well‐organized capillary‐like structures, whereas derangements in tube formation were noted in MCECs exposed to high glucose. The protein expression of transforming growth factor‐β1 (TGF‐β1) and phospho‐Smad2 was significantly increased by exposure to high glucose.ConclusionThe Matrigel‐based sprouting endothelial cell culture system is a simple, technically feasible, and reproducible technique for isolating pure cavernous endothelial cells in mice. An in vitro model for diabetic ED will be a valuable tool for evaluating the angiogenic potential of novel endogenous or synthetic modulators. Yin GN, Ryu J‐K, Kwon M‐H, Shin SH, Jin HR, Song K‐M, Choi MJ, Kang D‐Y, Kim WJ, and Suh J‐K. Matrigel‐based sprouting endothelial cell culture system from mouse corpus cavernosum is potentially useful for the study of endothelial and erectile dysfunction related to high‐glucose exposure. J Sex Med 2012;9:1777–1789.  相似文献   
995.
Objective:To examine the validation and reliability of the distress thermometer(DT) recommended by National Comprehensive Cancer Network(NCCN) in Chinese cancer patients.Methods:A total of 574 Chinese cancer patients from Beijing Cancer Hospital completed the detection of DT,the Hospital Anxiety and Depression Scale(HADS) and Symptom Checklist 90(SCL-90),Receiver Operating Characteristic(ROC) curve and Area Under the Curve(AUC) were used to analyze the validation relative to HADS and SCL-90.The patients with DT≥4 and whose distress caused by emotional problems were interviewed with the MiNi International Neuro-psychiatric Interview(MINI)(Chinese Version 5.0).This version was used to analyze cancer patients’ psychological and Psychiatric symptoms during the cancer process;3.Another 106 cancer patients in rehabilitation stage and stable condition were asked to fill in DT two times,at the base time and after 7-10 days.Results:Data of ROC indicates that a DT cutoff score of 4 yielded AUC of 0.80 with a optimal sensitivity(0.80) and specificity(0.70) relative to HADS,and AUC of 0.83 with the greatest sensitivity(0.87) and specificity(0.72) against SCL-90.The DT also has acceptable test-retest reliability(r=0.800,P=0.000);According to the interview results,the most common psychiatric problems cancer patients have adjustment disorder,depression,and anxiety.Conclusion:The data suggest that DT has acceptable overall accuracy and reliability as a screening tool for testing distress severity and specific problems causing distress in Chinese cancer patients.It is worth being used in oncology clinic,the rapid screening and interview could help caregivers to identify psychological and psychiatric problems of cancer patients and provide useful information for further treatment.  相似文献   
996.
Microglandular adenosis (MGA) of the breast is a very rare and benign proliferative lesion. Most patients complain of a palpable breast mass that may arouse a clinical suspicion of breast cancer. Histopathologically, it is hard to distinguish MGA from breast cancer because of the lack of a myoepithelial layer and infiltrative proliferation. Several studies have reported a strong relationship between MGA and carcinoma arising in MGA, so the mass should be excised completely in cases of MGA determined from a core needle biopsy rather than observation. A 72-years-old woman presented with a palpable breast mass. On physical examination, a mass was palpable in the right upper outer quadrant area and somewhat fixed to the surrounding tissues and pectoralis major muscle. We could not detect any mass or dense lesion on mammography because of a grade 4 dense breast. Ultrasonographic findings revealed a low echoic lesion with indistinct margins. The result of a core needle biopsy was MGA, which was confirmed by excision. We report one case of MGA, which was believed to breast cancer clinically.  相似文献   
997.
以个案研究在中医心理学、中医遗传学中的应用为切入点,深入剖析了个案研究的特点、存在的哲学基础及重要意义,并从计量、时态、比较、典型等几个方面提出了个案研究的思路拓展。  相似文献   
998.
Background and Aim: The relationship between age and esophageal motility parameters (i.e. basal and residual pressure of the lower esophageal sphincter [LES]) remains to be established in achalasia patients, possibly because most previous studies did not distinguish between classic and vigorous achalasia patients. We investigated the relationship between age and esophageal motility parameters in both classic and vigorous achalasia patients. Methods: A retrospective review of esophageal manometry data in a single center was undertaken. Basal and residual pressure for LES was analyzed. A total of 103 achalasia patients were enrolled, comprising 84 classic and 19 vigorous types. They were subdivided into three different age groups as follows: 21–40 years old (group A), 41–60 years old (group B), and over 60 years old (group C). Results: In classic achalasia patients (M : F = 27:57, mean age = 44 ± 15 years old) the older age group showed a significantly higher basal LES pressure (49.62 ± 19.63 mmHg) than the younger age group (P < 0.0001). Moreover, the older age group also showed significantly high residual LES pressure (20.46 ± 8.61 mmHg) than the younger age group (P = 0.0006). In contrast, in vigorous achalasia patients (M : F = 12:7, mean age: 47 ± 15 years old) there were no difference between age and motility indices (all P > 0.05). Conclusion: In classic achalasia patients there appears to be a correlation between age and esophageal motility indices, especially basal and residual LES pressure. Such correlations do not appear to exist for vigorous achalasia patients.  相似文献   
999.
Please cite this paper as: Increased expression of MAP2 inhibits melanoma cell proliferation, invasion and tumor growth in vitro and in vivo. Experimental Dermatology 2010; 19 : 958–964. Abstract: Malignant melanoma (MM) is characterized by aggressive metastasis and high mortality rate. Microtubule‐associated proteins 2 (MAP2) is expressed abundantly in majority of melanocytic nevi and primary melanomas, but absent in metastatic melanomas. To determine whether MAP2 correlates with tumor progression of MM, we investigated the effects of MAP2 inhibition on the biological behaviour of metastatic melanoma in vitro and in vivo. Our results demonstrated that adenovirus‐mediated MAP2 induced apoptotic cell death and cell cycle arrest in metastatic human and mouse melanoma cell lines in vitro, and substantially inhibited the growth of melanomas in nude mice in vivo. In addition, intracellular expression of MAP2 was found to induce the morphologic alteration, suppress the migration and invasion and affect the assembly, stabilization and bundling of microtubules in melanoma cells. This is the first study that MAP2 expression significantly inhibits the growth of MM in vivo. Our results suggest that MAP2 may serve as a promising molecular target for therapy and chemoprevention of MM in humans.  相似文献   
1000.
目的探讨扩大联合脏器切除T4b期胃癌的疗效,总结手术经验。方法对2012年1月至2015年12月在哈尔滨医科大学附属第一医院手术治疗的128例T4b期胃癌临床资料进行回顾性分析。结果 85例行扩大联合脏器切除术(extended multi-organ resection,ER组),43例行姑息性手术(non-extended multi-organ resection,NER组)。随访ER组1年、2年、3年的生存率分别为65.38%、44.87%和38.46%,均高于NER组的35.13%、16.21%和5.41%,两者之间的差异均有统计学意义(P0.05)。ER组的并发症发生率为18.82%,高于NER组的4.65%,两组之间的差异有统计学意义(P0.05);ER组的围手术期病死率为2.35%,NER组为2.33%,两者之间的差异无统计学意义(P0.05)。结论扩大联合脏器切除是安全可行的,可以延长病人生存期,改善临床症状,提高生存质量。  相似文献   
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