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Antiproliferative Activity Against MCF‐7 Breast Cancer Cells by Diamino‐Triazaspirodiene Antifolates
Xiang Ma Renee Ser‐Peng Woon Paul Chi‐Lui Ho Wai‐Keung Chui 《Chemical biology & drug design》2009,74(3):322-326
Two triazaspirodienes, having similar phenoxy propyloxy side chain, were identified as potent mammalian dihydrofolate reductase inhibitors; one having a 6,5‐spiro bicyclic ring system (IC50 = 2.3 nm ) and the other a 6,6‐spiro bicyclic system (IC50 = 6.9 nm ). They also showed more than 50% antiproliferative activity against the MCF‐7 breast cancer cells at 20 μm . This study demonstrated the potential lead of the diamino‐triazaspirodienes in anticancer chemotherapeutical agents’ discovery. 相似文献
23.
John N. K. Hsiang Keith Y. C. Goh Xian-Lun Zhu Wai S. Poon 《Child's nervous system》1996,12(10):611-614
Head injury in children causes special concern in most communities. From 1989 to 1994, 2,785 children younger than 16 years old were admitted to our neurosurgical service because of head injury. Fall from a height was the major cause of head injury leading to admission in infants and children in preschool age groups, whereas traffic-related or bicycle-related accidents were more likely to be the cause of head injury for those aged 11–15 years. In all age groups there was a male preponderance. The overall mortality was 0.6%. Traffic-ralated accidents caused more severe injury and accounted for 67% of all fatalities. For patients under 6 years old, about 40% of head injuries occurred at home. Preventive measures for pediatric head injury in Hong Kong are suggested. 相似文献
24.
Background: As in many parts of the world, the Schirmer tear test is the main test used by optometrists in Saudi Arabia for assessing adequacy of tear production. Variability of the test has been reported in different ethnic groups but not in Arabs. This paper looks at the mean and repeatability of the values obtained by the Schirmer test in a normal Arab population Method: The test was performed on the right eyes of 23 young adult Saudi male subjects at five visits over two weeks. Result: Results showed that for each subject the test values were not repeatable, varying widely over the period of evaluation. The mean value was estimated at 10.6 mm and the 95 per cent confidence limits were 7.9 and 13.3 mm. It was also established that the greater the amount of tears, the greater the variability. Conclusion: This study supports the claim that the Schirmer test is not repeatable and hence is unreliable. Therefore, caution should be exercised in employing it for clinical diagnosis. (Clin Exp Optom 1995; 78: 5: 190–193) 相似文献
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Patrick Callaghan RN BSc MSc Cheung Siu Shan RN BN Lau Suk Yu RN BN Lo Wai Ching RN BN Tsui Lai Kwan RN BN 《Journal of advanced nursing》1997,26(1):33-40
This study investigated whether previous contact with mental illness affected the attitudes to mental illness (AMI) of general student nurses in Hong Kong — the contact hypothesis. We employed a quasi-experimental design. We compared the attitudes to mental illness of students who had previous contact with mental illness through having taken a psychiatric secondment with those who had not taken a psychiatric secondment. Also, we compared the AMI of: students who had taken other courses related to mental illness with those who had not; those who had a family history of mental illness with those who had not; and those who lived with a mentally ill relative with those who did not. We found that previous contact with mental illness had no significant effect on the attitudes to mental illness of the students. In other words our findings do not support the contact hypothesis. Our sample expressed positive general attitudes to mental illness when presented with general issues about mental illness. However, their attitudes were less positive when presented with specific issues about mental illness that might impinge upon their daily lives. We discuss the implications of these findings for mental health nursing practice, education and research. 相似文献
27.
Should cervical ultrasonography be a routine staging investigation for lung cancer patients with impalpable cervical lymph nodes? 总被引:3,自引:0,他引:3
Alan D L Sihoe Tak Wai Lee Anil T Ahuja Anthony P C Yim 《European journal of cardio-thoracic surgery》2004,25(4):486-491
OBJECTIVES: Detection of cervical N3 lymph nodes is currently not a routine preoperative investigation for lung cancer patients. We designed a study to assess if the frequency and accuracy of detection of metastatic cervical lymph nodes using cervical ultrasonography (US) and fine needle aspiration (FNA) justify their routine use in all lung cancer patients with impalpable cervical lymph nodes. METHODS: Fifty patients with suspected and potentially operable non-small cell lung cancer were enrolled. Patients with palpable cervical lymph nodes were excluded. In addition to routine preoperative investigations, all patients received cervical US to determine the presence of cervical lymph nodes. Nodes suspicious of harboring malignancy according to a specific set of sonographic criteria (which include shape, echogenicity, nodal architecture, and vascular patterns) were subjected to biopsy by ultrasound-guided FNA. RESULTS: Normal cervical lymph nodes were detected by cervical US in 30 patients (60%). Cervical lymph nodes suspicious of harboring malignancy were detected in 10 patients (20%). FNA confirmed cervical nodal metastasis in four of these patients (8%). The TNM staging of two patients (4%) was revised up to stage IIIb as a result, excluding them from further surgery. Cost analysis suggests this technique to be cost-effective when used as a routine preoperative investigation to exclude patients from unnecessary surgical intervention. No mortality or complications were encountered in all patients. CONCLUSIONS: Cervical US and FNA is a safe and cost-effective method of evaluating the status of impalpable cervical lymph nodes in lung cancer patients. Further study is warranted to establish the role of cervical US and FNA in lung cancer staging algorithms. 相似文献
28.
Rectus sheath haematoma is a well‐documented but unusual cause of acute abdomen. Combination of clinical features and appropriate radiological investigations can make for a prompt diagnosis. Most authors advocate conservative management and it has been reported that patients were directly discharged from the emergency department. We report a case of rectus sheath haematoma which progressed with clinical deterioration and necessitated surgical intervention for clot evacuation. Causes, physical signs, radiological features and classification of rectus sheath haematoma are discussed. It may be necessary to continue close clinical monitoring after diagnosis of rectus sheath haematoma. 相似文献
29.
T J Tucker W C Lumma L S Payne J M Wai S J de Solms E A Giuliani P L Darke J C Heimbach J A Zugay W A Schleif 《Journal of medicinal chemistry》1992,35(14):2525-2533
A series of HIV-1 protease inhibitors containing a novel hydroxyethyl secondary amine transition state isostere has been synthesized. The compounds exhibit a strong preference for the (R) stereochemistry at the transition state hydroxyl group. Molecular modeling studies with the prototype compound 11 have provided important insights into the structural requirements for good inhibitor-active site binding interaction. N-Terminal extension of 11 into the P2-P3 region led to the discovery of 19, the most potent enzyme inhibitor in the series (IC50 = 5.4 nM). 19 was shown to have potent antiviral activity in cultured MT-4 human T-lymphoid cells. Comparison of analogs of 19 with analogs of 1 (Ro31-8959) demonstrates that considerably different structure-activity relationships exist between these two subclasses of hydroxyethylamine HIV-protease inhibitors. 相似文献
30.
阳痿是男子精神上最痛苦的一种常见的性功能障碍疾病,在中医男科诸证中,占有较大的比例。细读《实用中医内科学》、部分男科学专著及公开发表的论文,运用辨证论治的方法开展对阳痿的治疗及研究,仍然是当前的主导方向。在临床实践中常常会遇到这样的病例:除了阳痿以及因阳痿产生的痛苦外,其余无任何症状,无虚象、无实象、舌脉亦然。熟记分型标准,也不能对号入座。可以说,以阳痿为主诉而就诊者,无证可辩的并非少数,辨证而后论治,无证可辨论治也就无所依凭了。通过反复阅读古代文献及现代男科学专著,结合临床经验,就阳痿的治疗谈一点体会。性功… 相似文献