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31.
QUADAS评价:一种用于诊断性研究的质量评价工具(修订版) 总被引:2,自引:0,他引:2
背景 QUADAS是一种新近发展起来的诊断性研究的质量评价工具。虽然已有系统评价采用了QUADAS,但尚未得以正式确证。本研究的目的是评价QUADAS的有效性和实用性。方法3位评价者采用QUADAS独立评价30项研究的质量。比较每位评价者的评分与最终结论之间的意见一致度。这主要是通过比较所有QUADAS条目的总分和每个单项的得分来实现的。20位曾在其系统评价中使用过QUADAS的评价者就其使用经验完成一份简短的问卷。结果就所有条目而言,每位评价者的评分与最终结论之间的意见一致度分别达到了91%、90%和85%。就单项QUADAS条目而言,一致度在50%至100%之间,中位值是90%。与难以解释的试验结果和退出病例相关的条目,评分结果差异最大。有关QUADAS内容的反馈意见普遍较好,仅少数评价者提出了有关QUADAS涵盖面、使用便利性、评分说明的清晰度及有效性方面的问题。结论QUADAS内容本身无需作大的修改。评价过程的主要困难出现在难以解释的试验结果和退出病例这2个条目的评分上。对这些条目的评分指南提出了修改意见。评价者必需根据其系统评价制定相应的评分指南,并确保所有评价者都清楚如何评分。评价者还应考虑是否所有的QUADAS条目都与其系统评价相关,以及其他质量条目是否应作为其系统评价的评价部分。 相似文献
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33.
Baykara M Akkus M Yildiz R Gonul II Dursun A Coskun U Benekli M Sevinc A Dane F Buyukberber S 《International immunopharmacology》2011,(12):2227-2231
This study was designed to determine the level of survivin expression and its clinical significance as a prognostic factor in gastrointestinal stromal sarcoma (GIST). Twenty patients (12 males and 8 females) ranging in age from 25 to 72, with a median age of 53 were evaluated. Failure of TKI treatment was higher in the survivin-positive group (p = 0.06). The rate of metastasis was significantly higher in the survivin positive group vs. the negative group (80% vs. 30%, p = 0.18). The median overall survival (OS) time was 114 (range 29–199) months, and the median disease-free survival (DFS) time was 88 (range 40–135) months. The median progression-free survival (PFS) time was 40 (range 24–55) months. Further, a comparison of patients with survivin positive versus negative tumors, revealed no significant difference for OS, DFS, and PFS (p = 0.45, p = 0.19, p = 0.55, respectively), number of mitoses in 50 HPF (p = 0.14), and tumor size (p = 0.94).In conclusion, survivin was highly expressed in GISTs, although we found no correlation between survivin expression and PFS, DFS and OS, survivin may be a predictive marker in GISTs for disease progression. We believe that additional studies are warranted to determine the clinical significance of survivin expression as a prognostic or predictive marker in patients with GIST. 相似文献
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Pregnancy augments nitric oxide-dependent dilator response to acetylcholine in the human uterine artery 总被引:4,自引:1,他引:3
Nelson SH; Steinsland OS; Suresh MS; Lee NM 《Human reproduction (Oxford, England)》1998,13(5):1361-1367
The influence of pregnancy on the dilator effects of acetylcholine in the
isolated human uterine artery was investigated. Acetylcholine (0.1 nM to
0.1 microM) produced concentration- and endothelium-dependent relaxation of
norepinephrine (3 microM)-induced contraction. The relaxation was greater
in arteries from pregnant patients (P arteries) than from non-pregnant
patients (NP arteries). The maximal relaxation was 53.5+/-3.4% (n=21) in P
arteries and 23.5+/-2.5% (n=35) in NP arteries. In both P and NP arteries
the cholinergic relaxation was increased in the presence of superoxide
dismutase and greatly reduced in the presence of the nitric oxide synthase
inhibitors, NG-mono-methyl L-arginine (L-NMMA) and
L-nitro-arginine-methylester (L-NAME). The effect of these nitric oxide
synthase inhibitors was reversed by L- arginine. We conclude that pregnancy
enhances acetylcholine-induced nitric oxide synthesis and release in the
human uterine artery.
相似文献
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37.
Sari R Camci C Kutlu R Totan Y Sevinc A Buyukberber S 《International journal of clinical practice》2001,55(7):488-490
Breast carcinoma is the most frequent cancer in women and is the second leading cause of death. Choroid metastasis of breast carcinoma can be found either at presentation or in remission. It is frequently encountered in disseminated breast cancer with multiple organ metastasis. It has been proposed that the oedema-reducing effect of acetazolamide is due to stimulated ion and fluid removal from the retina to the choroid. A 40-year-old female patient on adjuvant chemotherapy for breast cancer was found to have an isolated choroid metastasis. Clinical and radiological remission was achieved after orbital radiotherapy, chemotherapy and acetazolamide treatment. In this case report, we emphasise the possible beneficial effect of acetazolamide in patients with choroid metastasis. 相似文献
38.
Overexpression of cyclooxygenase-2 in multiple myeloma: association with reduced survival 总被引:6,自引:0,他引:6
Cetin M Buyukberber S Demir M Sari I Sari I Deniz K Eser B Altuntas F Camci C Oztürk A Turgut B Vural O Unal A 《American journal of hematology》2005,80(3):169-173
Cyclooxygenases (COX) are key enzymes in the conversion of arachidonic acid to prostaglandins. Several studies have shown a relation between angiogenesis and COX-2 expression. Elevated expression of cyclooxygenase-2 (COX-2), however, has not been reported in multiple myeloma (MM) in the literature. The aim of this study is to investigate COX-2 expression in MM as well as its correlation with prognostic factors and estimated survival rates. Immunohistochemical staining of the paraffin-embedded bone marrow biopsy tissues (n = 51) was performed using isoform-specific COX-2 polyclonal antisera (Santa Cruz Biotechnology, Santa Cruz, CA). Results were correlated with recognized clinical parameters, which were retrospectively obtained from patients' files. There were 15, 19, and 17 bone marrow biopsy specimens with negative, weak-moderate, and strong COX-2 immunostaining, respectively. According to univariate analysis, beta2-microglobulin, age, stage, COX-2 expression, and serum lactate dehydrogenase levels were significant prognostic factors for survival in patients with multiple myeloma. COX-2 expression, age, and serum lactate dehydrogenase levels (greater than 1x normal level) were significant prognostic factors by multivariate analysis. Kaplan-Meier overall survival estimate of those patients with negative or weak-moderate COX-2 immunoreactivity in myeloma cells was significantly better than that of patients with strong COX-2 immunoreactivity (log-rank chi(2) = 21,43, P < 0.001). COX-2 overexpression was associated with reduced estimated survival. Poor prognostic factors such as LDH, age, and beta2-microglobulin were also correlated with COX-2 expression. Potent, specific COX-2 inhibitors showing evident antiangiogenic and antitumor effects on cancers could provide new therapeutic strategies in the treatment of MM. 相似文献
39.
Dengue is a mosquito transmitted flaviviral infection which can give rise to severe haemorrhage (dengue haemorrhagic fever) and with capillary leakage induces hypovolaemic shock (dengue shock syndrome). Although dengue symptoms and complications have been known for many decades, there has only been one documented case of osteonecrosis of the maxilla which was treated by excision of the necrotic bone. In this case of dengue infection, extensive maxillary osteonecrosis and minimal root resorption appeared to follow factitious injury with a toothpick but resolved with non‐surgical management. 相似文献
40.