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141.
142.
Abdel-Rahman HM Al-karamany GS El-Koussi NA Youssef AF Kiso Y 《Current medicinal chemistry》2002,9(21):1905-1922
A literature review on the human immunodeficiency virus (HIV), the causative agent of acquired immune deficiency syndrome (AIDS). This review includes its life cycle, HIV protease structure, function, and substrates, as well as the mechanism and the design of inhibitors including the clinically approved drugs. Moreover the review mentioned the problems that hindered the development of peptidomimetic drug candidates as HIV protease inhibitors and the different approaches used by medicinal chemists to overcome these problems. A special attention was made to the design rationale as well as the lead optimization processes that provided inhibitors that possess high potency, reduced molecular weight and lower lipophilicity of the allophenylnorstatine (Apns) containing HIV protease inhibitors. 相似文献
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This study evaluates the most widely used sonographic measurements for judging an infant's hip morphology. The alpha and beta angles of Graf, the bony coverage percentage of Morin and a new combined angle were analysed. This latter angle records the direction of the whole acetabulum (cartilagenous and bony) as one unit. One-hundred sonograms were examined independently by two observers to calculate the interobserver and intraobserver limits of agreement. The new combined angle proved to be the most reproducible measurement. Graf's alpha angle was the second most reliable measurement followed by the bone coverage percentage. The relationship between the combined angle and alpha angle was statistically significant with a correlation coefficient of 0.70 (P<0.001). 相似文献
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RM Subramaniam J Sherriff K Holmes MC Chan B Shadbolt 《Journal of Medical Imaging and Radiation Oncology》2006,50(5):442-446
This study was conducted to establish clinicians’ perspectives of a set of radiology curriculum topics for medical student teaching, which were held to be important by radiologists. A questionnaire was sent to clinicians in all specialties. Forty‐six clinicians (51.1%) out of 90 returned the questionnaires. All curriculum topics were scored above an average of 4 (agree). The five highest ranking curriculum topics in order of importance were: developing a system for viewing chest radiographs (5.59), developing a system for viewing abdominal radiographs (5.56), developing a system for viewing bone and joint radiographs (5.33), distinguishing normal structures from abnormal in chest and abdominal radiographs (5.33) and identifying gross bone or joint abnormalities in skeletal radiographs (5.22). Correlative analysis between speciality groups showed surgical and medical specialities were significantly different in their responses of two learning outcomes: basic knowledge about the contrast media benefits and risks (P= 0.01) and ability to select the most appropriate and the most cost‐effective methods of radiological investigations for clinical situations (P= 0.03). Acute specialities were not significantly different from the other two groups for these two learning outcomes. There was no statistically significant difference for other learning outcomes between the three speciality groups. 相似文献
148.
Telesurgery is a form of operative videoconferencing in which a remotely located surgeon observes a procedure through a camera and provides visual and auditory feedback to the operative site. With the use of more robotic devices in laparoscopic surgery, various forms of telesurgery have been tried. We describe the first two international telesurgical, telementored, robot-assisted laparoscopic cholecystectomies performed in the world, between the Johns Hopkins Institute, Baltimore, Maryland, USA, and the National University Hospital, Singapore. 相似文献
149.
BACKGROUND/AIMS: The purpose of this study was to determine at what concentration does platelet-derived growth factor-BB (PDGF-BB) provide for optimal stimulation of human periodontal ligament fibroblasts (PDL) to adhere to periodontitis affected root surfaces. METHOD: 80 root dentine specimens were prepared from extracted periodontally diseased teeth obtained from patients ranging in age between 35 to 60 years. The root dentine specimens were associated with the subgingival area opposing the periodontal pocket for each extracted tooth. 10 healthy root dentine specimens were obtained from teeth extracted for orthodontic reasons and served as controls. The specimens were distributed into 9 groups (10 specimens in each). In group 1, PDL fibroblasts were cultured on the specimen surface of a diseased treated control. In group 2, PDL fibroblasts were cultured on the specimen surface of a healthy control. In groups 3 to 9, PDL fibroblasts were cultured on a pre-treated specimen surface with concentrations ranging from 5, 10, 20, 50, 100, 200 and 300 ng/ml PDGF-BB, respectively. After 24 h incubation, the media were removed, specimens were fixed, processed for SEM viewing and photographed at 750x. Fibroblast adherence was measured by counting number of cells within a standard test area and cell morphology was scored. RESULTS: Findings suggest dentine specimens pretreated with 5, 10 and 20 ng/ml PDGF-BB were not significantly different in number of adherent cells from the diseased treated control. However, at concentrations of 50, 100, 200 and 300 ng/ml, a highly significant increase in number of adherent fibroblasts was detected when compared to the diseased treated control. At these concentrations, the cell morphology was comparable to that of the healthy control. CONCLUSIONS: PDGF-BB in concentrations equal to or greater than 50 ng/ml demonstrates a significant stimulation of PDL cells adherence to periodontal diseased root surfaces. Since the higher concentrations resulted in similar effects as obtained by 50 ng/ml, it may therefore be considered that this concentration provides for optimal stimulation of human periodontal ligament fibroblasts (PDL) to adhere to periodontitis-affected root surfaces. 相似文献
150.
Induction of oxidative DNA base damage in human skin cells by UV and near visible radiation 总被引:11,自引:2,他引:11
The premutagenic oxidative DNA base damage, 7,8-dihydro-8-oxoguanine, is
induced in human skin fibroblasts by monochromatic radiation ranging from a
UVB wavelength (312 nm) up to wavelengths in the near visible (434 nm). The
oxidative damage is not generated by absorption of radiation in DNA but
rather by activation of photosensitizers generating genotoxic singlet
oxygen species. The spectrum for the yield of the oxidative damage in
confluent, non-growing, primary skin fibroblasts shows that it is UVA
(above 334 nm) and near visible radiations which cause almost all of this
guanine oxidation by natural sunlight in the fibroblast model. We estimate
that the total amount of oxidation of guanine induced by sunlight in
fibroblasts in the epidermis of the skin equals or exceeds the amount of
the major type of direct DNA damage, cyclobutane pyrimidine dimers. In
rapidly dividing lymphoblastoid cells, no oxidative guanine damage was
induced. However, in melanoma cells almost as much damage as in non-growing
fibroblasts (1.1 per 10(4) guanine bases after 1200 kJ/m2 UVA) was found.
We conclude that oxidative DNA base damage can probably contribute to the
induction of both non-melanoma and melanoma skin cancer by sunlight.
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