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271.
Cerebral sparganosis: MR imaging versus CT features   总被引:5,自引:0,他引:5  
Moon  WK; Chang  KH; Cho  SY; Han  MH; Cha  SH; Chi  JG; Han  MC 《Radiology》1993,188(3):751
  相似文献   
272.
Rahn  NH  d; Tishler  JM; Han  SY; Russinovich  NA 《Radiology》1982,143(2):361
  相似文献   
273.
尼莫地平多晶型的研究   总被引:16,自引:0,他引:16  
王晋  张汝华  孙淑英 《药学学报》1995,30(6):443-448
用不同有机溶剂重结晶制备了尼莫地平的两种晶型H和L,并通过红外光谱、X-射线粉末衍射、差热分析等方法得到证实。实验测定了尼莫地平两种晶型的溶解度曲线,并计算热力学数据。  相似文献   
274.
王岚  徐焕霞  王雁  胡继文  郝绥雁 《医学争鸣》2005,26(18):1694-1694
1临床资料本组患者86例,年龄40~74(平均56)岁,急性肾功能衰竭15例,慢性肾功能衰竭62例,严重的水电解质紊乱、酸碱失衡和不宜行血液透析9例,行腹膜透析2mo4a.  相似文献   
275.
276.

Background

Hypoxia-inducible factor-1 alpha (HIF-1α) maybe an important regulatory factor for angiogenesis of small cell lung cancer (SCLC). Our study aimed to investigate the effect of HIF-1α on angiogenic potential of SCLC including two points: One is the effect of HIF-1α on the angiogenesis of SCLC in vivo. The other is the regulation of angiogenic genes by HIF-1α in vitro and in vivo.

Methods

In vivo we used an alternative method to study the effect of HIF-1a on angiogenic potential of SCLC by buliding NCI-H446 cell transplantation tumor on the chick embryo chorioallantoic membrane (CAM) surface. In vitro we used microarray to screen out the angiogenic genes regulated by HIF-1a and tested their expression level in CAM transplantation tumor by RT-PCR and Western-blot analysis.

Results

In vivo angiogenic response surrounding the SCLC transplantation tumors in chick embryo chorioallantoic membrane (CAM) was promoted after exogenous HIF-1α transduction (p < 0.05). In vitro the changes of angiogenic genes expression induced by HIF-1α in NCI-H446 cells were analyzed by cDNA microarray experiments. HIF-1α upregulated the expression of angiogenic genes VEGF-A, TNFAIP6, PDGFC, FN1, MMP28, MMP14 to 6.76-, 6.69-, 2.26-, 2.31-, 4.39-, 2.97- fold respectively and glycolytic genes GLUT1, GLUT2 to2.98-, 3.74- fold respectively. In addition, the expression of these angiogenic factors were also upregulated by HIF-1α in the transplantion tumors in CAM as RT-PCR and Western-blot analysis indicated.

Conclusions

These results indicated that HIF-1α may enhance the angiogenic potential of SCLC by regulating some angiogenic genes such as VEGF-A, MMP28 etc. Therefore, HIF-1α may be a potential target for the gene targeted therapy of SCLC.  相似文献   
277.
278.
Outbreaks of dengue due to dengue virus type 1 (DENV-1) occurred almost simultaneously in 2001 in Myanmar and at multiple sites almost 10,000 km away in the Pacific. Phylogenetic analyses of the E protein genes of DENV-1 strains recovered from Asia and the Pacific revealed three major viral genotypes (I, II, and III) with distinct clades within each. The majority of strains from the Pacific and Myanmar, and a number of other Asian strains fell into genotype I. Genotype II comprised a smaller set of Asian and Pacific strains, while genotype III contained viruses from diverse geographical localities. These analyses suggested that the continuing outbreak of dengue in the Pacific has been due to multiple, direct, introductions of dengue viruses from a variety of locations in Asia followed by local transmission. There was no evidence that the introduction of these viruses into the Pacific was associated with any adaptive changes in the E protein of the viruses.  相似文献   
279.

Background

Improving questionnaire response rates is an everlasting issue for research. Today, the Internet can easily be used to collect data quickly. However, collecting data on the Internet can lead to biased samples because not everyone is able to access or use the Internet. The older population, for example, is much less likely to use the Internet. The Patient-Reported Outcomes Following Initial Treatment and Long-Term Evaluation of Survivorship (PROFILES) registry offers a platform to collect Web-based and paper questionnaires and to try different measures to improve response rates.

Objective

In this study, our aim was to study the influence of two methods of invitation on the response rate. Our second aim was to examine the preference of questionnaire mode of administration (paper or Web-based) for the older patient in particular.

Methods

To test these two invitational methods, 3406 colorectal cancer patients between ages 18 and 85 years received an invitation containing an access code for the Web-based questionnaire. They could also request a paper questionnaire with an included reply card (paper-optional group). In contrast, 179 randomly selected colorectal cancer patients received a paper questionnaire with the invitation (paper-included group). They could also choose to fill out the Web-based questionnaire with the included access code.

Results

Response rates did not differ between the paper-optional and the paper-included groups (73.14%, 2491/3406 and 74.9%, 134/179, P=.57). In the paper-optional group, online response was significantly higher when compared to the paper-included group (41.23%, 1027/2491 vs 12.7%, 17/134, P<.001). The majority of online respondents responded after the first invitation (95.33%, 979/1027), which was significantly higher than the paper respondents (52.19%, 764/1464, P<.001). Respondents aged 70 years and older chose to fill out a paper questionnaire more often (71.0%, 677/954). In the oldest age group (≥80 years), 18.2% (61/336) of the respondents filled out a Web-based questionnaire.

Conclusions

The lack of difference in response rates between invitation modes implies that researchers can leave out a paper questionnaire at invitation without lowering response rates. It may be preferable not to include a paper questionnaire because more respondents then will fill out a Web-based questionnaire, which will lead to faster available data. However, due to respondent preference, it is not likely that paper questionnaires can be left out completely in the near future.  相似文献   
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