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991.
Rajiv Samant Inge Aivas Jean-Marc Bourque Tara Tucker 《Journal of cancer education》2010,25(4):474-477
Shared decision making (SDM) and effective communication are essential components of cancer care. Residents in oncology-related
specialties were surveyed about communication skills and SDM. The response rate was 77% (17/22), and 93% stated that communication
skills were very important for their specialty. Most (76%) thought their communication skills were adequate, but areas of
difficulty included discussing end-of-life issues, giving hope when the prognosis was bleak and dealing with hostile patients.
Only 58% of respondents had heard the term SDM, and 29% were aware of its meaning. More SDM and communication training are
required for future oncology physicians. 相似文献
992.
Cristina Luceri Lisa Giovannelli Vanessa Pitozzi Simona Toti Cinzia Castagnini Jean-Marc Routaboul Loic Lepiniec Mar Larrosa Piero Dolara 《Food and chemical toxicology》2008,46(4):1213-1220
Plant polyphenols, such as flavonoids, comprise many compounds, ranging from simple phenolic molecules (i.e. flavonols, anthocyanins) to polymeric structures with high molecular weight (as proanthocyanidins, PAs). We investigated the effects of flavonoids by feeding Wistar rats Arabidopsis thaliana seeds carrying mutations in key enzymes of the flavonoid biosynthetic pathway (15% w/w seeds for 4 weeks). The seeds used were: Ws-2 wild-type containing flavonols and PAs, tt3-4 mutant containing flavonols only, ban-5 accumulating flavonols and anthocyanins, tt4-8 mutant, deprived of flavonoids. DNA oxidative damage was significantly reduced only in the liver of rats fed tt3-4 mutant seeds. Microarray analysis of the liver revealed down-regulation of genes associated with oxidative stress, Krebs cycle, electron transport and proteasome degradation in all experimental groups compared to the tt4-8-fed reference rats; therefore, these effects were due to the flavonol content and not to high molecular weight compounds. We observed a down-regulation of inflammatory response genes in the colon mucosa in ban-5- fed rats, probably due to anthocyanin content. In conclusion, flavonols exhibited antioxidant effects at systemic level, whereas high molecular weight flavonoids affected only the colon, probably due to their limited absorption. 相似文献
993.
994.
Jean-Marc Gabastou Carmen Pesantes Santiago Escalante Yolanda Narváez Enrique Vela Lidia García Diana Zabala Zaida E Yadon 《Pan American journal of public health》2002,12(3):157-164
OBJECTIVE: To describe the outbreak of cholera that occurred in Ecuador in 1998 during the El Nino weather phenomenon, to present data on the resistance of the circulating strains of Vibrio cholerae to antimicrobial drugs, and to describe the preventive measures taken by health authorities in order to reduce the impact of the disease. METHODS: The epidemiological data came from three sources: 1) the registry of the National Bureau of Epidemiology of the Ministry of Public Health of Ecuador, 2) the registry of the National Institute of Hygiene and Tropical Medicine, and 3) the final report of the Training Program for the Fight against Cholera and Diarrheal Diseases. Isolation, identification, and serotyping was done of V. cholerae in the feces samples from 10% of the suspected cholera cases that were identified between 1 January and 31 December 1998. The suspected cases were defined by the sudden appearance of watery diarrhea, with or without dehydration, in epidemic areas. The strains that were isolated were submitted to a standard antibiogram by the diffusion method, in which the following antibiotics were tested: amoxicillin, tetracycline, trimethoprimsulfamethoxazole, vibriostatic compound O/129, nalidixic acid, erythromycin, norfloxacin, ciprofloxacin, gentamycin, chloramphenicol, and colistin. RESULTS: In 1998 there were 3 755 cases reported in 17 of the 21 provinces of the country. This corresponds to an incidence rate of 53.96 per 100 000 population. Thirty seven patients died, for a case fatality rate of 0.97%. A total of 301 strains of V. cholerae were isolated in the 637 suspected-cholera samples that were processed; all corresponded to V. cholerae O1, El Tor, subtype Ogawa. All of the strains were sensitive to tetracycline and to quinolones; 5.6% of the strains were resistant to erythromycin. The only strain resistant to amoxicillin was multiresistant. Officials in Ecuador implemented a series of preventive measures, and the surveillance system was strengthened in order to reduce the impact of the disease. CONCLUSIONS: The preventive measures helped to reduce the impact of the 1998 cholera epidemic in Ecuador, in terms of both incidence and the case fatality rate. Given the overall sensitivity of the strains to the antimicrobial drugs, there is no reason to change the current treatment regimens in the country. Taking into account the frequency of natural disasters in Ecuador and the relation that they have to the reappearance of cholera, interventions should be designed that make it possible to prevent and control the reappearance of the disease and its spread to the most vulnerable provinces of the central Sierra mountainous region and the eastern part of the country. 相似文献
995.
Corticoids normalize leukocyte production of macrophage migration inhibitory factor in septic shock 总被引:6,自引:0,他引:6
BACKGROUND: A regulatory loop between macrophage migration inhibitory factor (MIF) and glucocorticoids has been characterized in animal models. Renewed interest in glucocorticoid treatment for septic shock offers an opportunity to analyze this regulatory loop in humans. METHODS: We investigated the ex vivo release of MIF by peripheral blood mononuclear cells (PBMCs) sampled from glucocorticoid-treated and -untreated patients with septic shock. Blood was obtained, before glucocorticoid treatment, and within the first day of treatment, from patients with septic shock who required treatment with moderate doses of hydrocortisone and fludrocortisone. RESULTS: PBMCs from patients contained significantly higher amounts of MIF than cells from healthy control subjects. In culture, spontaneous release of MIF and release induced by lipopolysaccharide (LPS), heat-killed staphylococci, and red blood cell lysates were significantly higher in patients than in control subjects. PBMCs from patients treated with glucocorticoids showed a lower release of MIF in response to LPS, heat-killed Escherichia coli, and peptidoglycan than did PBMCs from untreated patients and showed levels similar to PBMCs from healthy control subjects. CONCLUSION: To our knowledge, MIF is the first proinflammatory cytokine in which ex vivo release by circulating cells is enhanced during sepsis. Glucocorticoid treatment normalized the release of MIF by circulating PBMCs from patients with septic shock. 相似文献
996.
A cysteine-rich motif confers hypoxia sensitivity to mammalian large conductance voltage- and Ca-activated K (BK) channel alpha-subunits 下载免费PDF全文
McCartney CE McClafferty H Huibant JM Rowan EG Shipston MJ Rowe IC 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(49):17870-17876
Cellular responses to hypoxia are tissue-specific and dynamic. However, the mechanisms that underlie this differential sensitivity to hypoxia are unknown. Large conductance voltage- and Ca-activated K (BK) channels are important mediators of hypoxia responses in many systems. Although BK channels are ubiquitously expressed, alternative pre-mRNA splicing of the single gene encoding their pore-forming alpha-subunits provides a powerful mechanism for generating functional diversity. Here, we demonstrate that the hypoxia sensitivity of BK channel alpha-subunits is splice-variant-specific. Sensitivity to hypoxia is conferred by a highly conserved motif within an alternatively spliced cysteine-rich insert, the stress-regulated exon (STREX), within the intracellular C terminus of the channel. Hypoxic inhibition of the STREX variant is Ca-sensitive and reversible, and it rapidly follows the change in oxygen tension by means of a mechanism that is independent of redox or CO regulation. Hypoxia sensitivity was abolished by mutation of the serine (S24) residue within the STREX insert. Because STREX splice-variant expression is tissue-specific and dynamically controlled, alternative splicing of BK channels provides a mechanism to control the plasticity of cellular responses to hypoxia. 相似文献
997.
Revascularization of ischemic tissues by PDGF-CC via effects on endothelial cells and their progenitors 总被引:10,自引:0,他引:10 下载免费PDF全文
Li X Tjwa M Moons L Fons P Noel A Ny A Zhou JM Lennartsson J Li H Luttun A Pontén A Devy L Bouché A Oh H Manderveld A Blacher S Communi D Savi P Bono F Dewerchin M Foidart JM Autiero M Herbert JM Collen D Heldin CH Eriksson U Carmeliet P 《The Journal of clinical investigation》2005,115(1):118-127
The angiogenic mechanism and therapeutic potential of PDGF-CC, a recently discovered member of the VEGF/PDGF superfamily, remain incompletely characterized. Here we report that PDGF-CC mobilized endothelial progenitor cells in ischemic conditions; induced differentiation of bone marrow cells into ECs; and stimulated migration of ECs. Furthermore, PDGF-CC induced the differentiation of bone marrow cells into smooth muscle cells and stimulated their growth during vessel sprouting. Moreover, delivery of PDGF-CC enhanced postischemic revascularization of the heart and limb. Modulating the activity of PDGF-CC may provide novel opportunities for treating ischemic diseases. 相似文献
998.
Allergy-like reactions may occur following administration of iodinated contrast media (CM), mostly in at-risk patients (patients with history of previous reaction, history of allergy, co-treated with interleukin-2 or beta-blockers, etc.) but remain generally unpredictable. Severe and fatal reactions are very rare events. All categories of CM may induce such reactions, although first generation (high osmolar CM) have been found to induce a higher rate of adverse events than low osmolar CM. However, no differences were found between the two categories of CM with respect to mortality. Delayed reactions can also occur. There are no differences between the various categories of CM except for non-ionic dimers, which are more likely to induce such effect. Numerous clinical studies have evaluated the prophylactic value of drugs (mostly antihistamines and corticosteroids). Results are unclear and highly variable. Any prevention depends upon the mechanism involved. However, the mechanism of CM-induced allergy-like reaction remains disputed. Relatively recent data revived the hypothesis of a type-I hypersensitivity mechanism. Positive skin tests to CM have been reported. However, the affinity of IgE towards CM has been found to be very low in the only study which actually evaluated it. Other pathophysiological mechanisms (involving direct secretory effects on mast cells or basophils, or activation of the complement system associated or not with the plasma contact system) are also much debated. Anaphylaxis and anaphylactoid reactions are, in the end, clinically undistinguishable. 相似文献
999.
Rhesus (Rh) D blood group incompatibility between the pregnant woman and her fetus is a significant problem due to the possibility of maternal alloimmunization and consequent hemolytic disease of the newborn. The RhD-negative blood group is found in 15% of whites, 3-5% of black Africans, and is rare in Asians. Advances in both our understanding of the RHD locus and its variants, as well as technical improvements in the extraction and amplification of cell-free fetal DNA in maternal plasma, have led to incorporation of noninvasive diagnosis of RHD genotype into routine prenatal care in the United Kingdom, France, and the Netherlands. In this commentary we examine the experience to date with large-scale clinical trials performed in the European Union, describe approaches to reduce false-positive and false-negative results, and review ongoing research to standardize assays and reduce costs using automated assays. False-negative cases are mainly due to either a lack of fetal DNA in the maternal sample due to early gestation or insensitive methods. False-positive cases are due to genotypic variants observed in individuals of African ancestry. Noninvasive prenatal diagnosis of fetal Rhesus D genotype is sensitive and accurate and has been widely validated in Europe. The United States should begin to undertake clinical trials to bring this technology to patient care as soon as possible. 相似文献
1000.
Cytomegalovirus is the main cause of congenital viral infection and amniotic fluid viral load appears to be the single nonclinical prognostic factor. However, as in other infectious diseases, host genetics may influence the severity of the disease. To test this hypothesis, we looked retrospectively at the fetal gender in cases of severe congenital cytomegalovirus infection in our database. We also analyzed the international English literature covering this subject between 1985 and 2003. The proportion of females with brain abnormalities was statistically different from that of males (62/258: 24% vs 30/251: 12%, p = 0.004). The risk of abnormal brain development in infected fetuses was twice as high in females than in males (Chi(2) = 8.7; OR = 2, IC [1.26-3.21]). In our cases, amniotic fluid CMV DNA load was not significantly higher in males than in females (p = 0.06) and was also similar in severely and non-severely infected fetuses (p = 0.09). 相似文献