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991.
992.
Redirecting differentiation of hematopoietic progenitors by a transcription factor, GATA-2 总被引:1,自引:1,他引:0
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Kitajima K Tanaka M Zheng J Yen H Sato A Sugiyama D Umehara H Sakai E Nakano T 《Blood》2006,107(5):1857-1863
993.
994.
STUDY OBJECTIVE: Our purpose was to identify and examine the characteristics of the most frequently cited articles in the field of emergency medicine (EM). METHODS: Top-cited EM articles in 9 EM journals were identified by searching the computerized database of the Science Citation Index Expanded and the Web of Science (1972 to present). Median citation numbers, authors' nationalities, publication year, and fields of study were described and discussed. Mann-Whitney U and Kruskal-Wallis tests were used to compare groups. RESULTS: All top-cited articles were published during 1972 and 2002. We identified 100 top-cited articles published in 6 EM journals, led by Annals of Emergency Medicine (66) and American Journal of Emergency Medicine (22). Toxicology, traumatology, resuscitation medicine, and cardiovascular medicine were the primary focus of study. The median citation number for these top-cited articles was 102 (range, 71-335). CONCLUSION: Our analysis gives an encyclopedic review of citation frequency of top-cited articles published in EM journals, which may provide information for those who want to find the history, evolution, and areas of high-impact research activities of EM. 相似文献
995.
Reyes-Gibby CC Ba Duc N Phi Yen N Hoai Nga N Van Tran T Guo H Bhat S Cleeland C 《Journal of pain and symptom management》2006,31(5):431-439
Little is known about the prevalence of cancer pain in many developing countries. We report a hospital-wide survey of pain in a tertiary cancer center in Hanoi, Vietnam. All inpatients and outpatients age 18 years or older were approached for participation in the study. Data were collected using the Brief Pain Inventory. Results showed a 70% response rate. Prevalence of moderate to severe pain was 50% (89/178), with 23% reporting severe ratings of pain at its "worst" and 33% reporting severe impairment in their ability to work due to pain. Only 1% and 40% reported total and partial pain relief from medications, respectively. This study is among the first to provide a representative view of pain in a tertiary cancer treatment center in Hanoi, Vietnam. The findings provide empirical support for the need for better programmatic efforts to improve relief of cancer pain in developing countries, including Vietnam. 相似文献
996.
Deep brain stimulation of the subthalamic nucleus (STN DBS) has become an accepted tool for the treatment of Parkinson's disease (PD). Although the precise mechanism of action of this intervention is unknown, its effectiveness has been attributed to the modulation of pathological network activity. We examined this notion using positron emission tomography (PET) to quantify stimulation-induced changes in the expression of a PD-related covariance pattern (PDRP) of regional metabolism. These metabolic changes were also compared with those observed in a similar cohort of patients undergoing STN lesioning. We found that PDRP activity declined significantly (P < 0.02) with STN stimulation. The degree of network modulation with DBS did not differ from that measured following lesioning (P = 0.58). Statistical parametric mapping (SPM) revealed that metabolic reductions in the internal globus pallidus (GPi) and caudal midbrain were common to both STN interventions (P < 0.01), although declines in GPi were more pronounced with lesion. By contrast, elevations in posterior parietal metabolism were common to the two procedures, albeit more pronounced with stimulation. These findings indicate that suppression of abnormal network activity is a feature of both STN stimulation and lesioning. Nonetheless, these two interventions may differ metabolically at a regional level. 相似文献
997.
Tooth autotransplantation, allotransplantation and dental implants have existed for many years, but have never been totally satisfactory. Thus, the development of new methods of tooth replacement has become desirable, and with the increasing knowledge of stem cell biology becomes a realistic possibility. Stem cell-based tissue engineering involving the recapitulation of the embryonic environment demonstrates that dental, non-dental, embryonic and adult stem cells can contribute to teeth formation in the appropriate setting. Evidence that stem cell populations may be present in human teeth provides the opportunity to consider biological tooth replacement 'new for old'. 相似文献
998.
A short cut review was carried out to establish whether smectite was a useful therapy in acute diarrhoea. A total of 21 papers were found of which five presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses of these best papers are tabulated. The clinical bottom line is that oral smectite appears to be effective at shortening the duration of the diarrhoea in children with acute diarrhoea rehydrated with oral rehydration solution. 相似文献
999.
Chung V Zhou B Liu X Zhu L Boo LM Nguyen HV Ann DK Song J Chen Y Yen Y 《Molecular cancer therapeutics》2006,5(3):533-540
Bortezomib, a novel dipeptide boronic acid proteasome inhibitor, has been shown in previous studies to be synergistic with gemcitabine; however, the molecular mechanisms are not fully understood. Because post-translational modification of proteins, such as ubiquitination and SUMOylation, plays a critical role in governing cellular homeostasis, we explored this further by treating human oropharyngeal carcinoma KB wild-type (KBwt) and gemcitabine-resistant (KBGem) cells with gemcitabine and bortezomib in a time-dependent and sequence-dependent manner. Treatment with bortezomib at 4 to 8 hours post-gemcitabine significantly induced cell death in KBwt cell lines. However, in KBGem cells, bortezomib alone was just as cytotoxic. Using reporter assays, nuclear factor-kappaB (NF-kappaB) activity was found to be 5-fold higher in KBGem cells than that in KBwt cells, and the combination treatment decreased NF-kappaB activity by 44% in KBwt cells and 28% in KBGem cells, respectively. By Western blot analyses, treatment with gemcitabine and bortezomib resulted in a cleavage of NF-kappaB in KBwt but not in KBGem cells. SUMOylation capacity was modulated by transducing KBwt and KBGem cells with lenti-SUMO-1 or the unconjugatable lenti-SUMO-1aa followed by drug treatment. The expression of cyclins A, D1, and E was differentially regulated by SUMOylation capacity in KBGem but not in KBwt cells. We report herein that the activation of NF-kappaB signaling plays a critical role in eliciting KBwt cell survival against gemcitabine, whereas the role of SUMOylation in modulating the steady-state levels of key cell cycle regulator proteins seems more significant in KBGem cells. 相似文献
1000.
Anderson RH Ho SY Sanchez-Quintana D Redmann K Lunkenheimer PP 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2006,288(6):579-586
There is lack of consensus concerning the three-dimensional arrangement of the myocytes within the ventricular muscle masses. Bioengineers are seeking to model the structure of the heart. Although the success of such models depends on the accuracy of the anatomic evidence, most of them have been based on concepts that are far from anatomical reality, which ignore many significant previous accounts of anatomy presented over the past 400 years. During the 19th century, Pettigrew emphasized that the heart was built on the basis of a modified blood vessel rather than in the form of skeletal muscles. This fact was reemphasized by Lev and Simkins as well as Grant in the 20th century, but the caveats listed by these authors have been ignored by proponents of two current concepts, which state either that the myocardium is arranged in the form of a "unique myocardial band," or that the walls of the ventricles are sequestrated in uniform fashion by laminar sheets of fibrous tissue extending from epicardium to endocardium. These two concepts are themselves incompatible and are further at variance with the majority of anatomic studies, which have emphasized the regional heterogeneity to be found in the three-dimensional packing of the myocytes within a supporting matrix of fibrous tissue. We reemphasize the significance of this three-dimensional muscular mesh, showing how the presence of intruding aggregates of myocytes extending in oblique transmural fashion also contends against the notion that all myocytes are orientated with their long axes parallel to the epicardial and enodcardial surfaces. 相似文献