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排序方式: 共有6559条查询结果,搜索用时 15 毫秒
61.
Keflemariam Yohannes Paul Roche Charlie Blumer Jenean Spencer Alison Milton Chris Bunn Heather Gidding Martyn Kirk Tony Della-Porta 《Communicable diseases intelligence》2004,28(1):6-68
There were 57 infectious diseases notifiable at the national level in Australia in 2002. States and territories reported 100,278 cases of infectious diseases to the National Notifiable Diseases Surveillance System (NNDSS), a fall of 4 per cent compared to the number of notifications in 2001. In 2002, the most frequently notified diseases were, sexually transmitted infections (31,929 reports, 32% of total notifications), gastrointestinal infections (26,708 reports, 27% of total notifications) and bloodborne infections (23,741, 24%). There were 11,711 (12% of total) cases of vaccine preventable diseases, 3,052 (3% of total) cases of vectorborne diseases, 1,155 (1% of total) cases of zoonotic infections, two cases of quarantinable diseases (Vibrio cholerae O1) and 1,980 cases of other bacterial diseases, notified to NNDSS. Compared to 2001, notifications of sexually transmitted infections increased by 16 per cent and gastrointestinal infections by 2 per cent while bloodborne infections fell by 18 per cent. The number of notifications of chlamydial infection and Q fever were the highest since 1991 and 1995 respectively. By contrast, the number of notification for hepatitis A and measles were the lowest since 1991. For other notifiable diseases, the number of notifications was within the range of the five years between 1997 and 2002 (range = five-year mean plus or minus two standard deviations). This report also includes 2002 summary data on communicable diseases from other surveillance systems including the Laboratory Virology and Serology Reporting Scheme and sentinel general practitioner schemes. 相似文献
62.
Emotion/cognition-coupling in word recognition memory of depressive patients: an event-related potential study 总被引:7,自引:0,他引:7
Dietrich DE Emrich HM Waller C Wieringa BM Johannes S Münte TF 《Psychiatry research》2000,96(1):15-29
Depressive patients show deficits in memory functions. However, the underlying mechanisms remain unclear. Experiments with a special emphasis on the link between emotion and cognition appear challenging. The aim of this study is to investigate the influence of the emotional content of words on memory in non-medicated depressive patients (n=11) compared with a control group (n=11) utilizing event-related brain potentials (ERPs). In a continuous word recognition paradigm brain responses to repeated items are characterized by more positive waveforms of ERPs. This recognition effect ('old/new effect') has been shown to be sensitive to parameters relevant for memory processing. For the purpose of this ERP experiment visually presented words were classified into three different categories of emotional content. The ERPs for the correctly detected 'old' (repeated) words showed an increased positivity beginning approximately 250 ms post-stimulus, concurring with a good recognition performance. In addition, old/new effect and behavioral data were sensitive to words' different emotional connotations in the control group. In contrast, the depressive patients performed worse and showed no significant old/new effect. Nevertheless, their recognition performance was also enhanced by the emotional content. Furthermore, a differential effect of the emotional content on frontal ERPs was found between groups. In contrast to the control group, a reduced old/new effect indicates a reduced working memory capacity in the moderately depressed patients. This is suggested to be partially due to changes of the emotion/cognition coupling related to ruminations with preferably negative emotional connotation. However, the emotional content also affects recognition performance in the depressive patients. 相似文献
63.
Jan Vondrácek Miroslav Machala Vítezslav Bryja Katerina Chramostová Pavel Krcmár Cornelia Dietrich Ales Hampl Alois Kozubík 《Toxicological sciences》2005,83(1):53-63
Polychlorinated biphenyls (PCBs) exhibit tumor-promoting effects in experimental animals. We investigated effects of six model PCB congeners and hydroxylated PCB metabolites on proliferation of contact-inhibited rat liver epithelial WB-F344 cells. The 'dioxin-like' PCB congeners, PCB 126, PCB 105, and 4'-OH-PCB 79, a metabolite of the planar PCB 77 congener, induced cell proliferation in a concentration-dependent manner. In contrast, the 'non-dioxin-like' compounds that are not aryl hydrocarbon receptor (AhR) agonists, PCB 47, PCB 153, and 4-OH-PCB 187, an abundant noncoplanar PCB metabolite, had no effect on cell proliferation at concentrations up to 10 muM. The concentrations of dioxin-like PCBs leading to cell proliferation corresponded with the levels inducing the expression of cytochrome P450 1A1 mRNA, suggesting that the release from contact inhibition was associated with AhR activation. The effects of PCB 126 and PCB 153 on expression of proteins controlling G0/G1-S-phase transition and S-phase progression were compared. Only PCB 126 was found to upregulate cyclin A and D2 protein levels, and to increase both total cyclin-dependent kinase 2 (cdk2) and cyclin A/cdk2 complex activities. Despite the observed upregulation of cyclin D2, no increase in cdk4 activity was observed. The expression of cdk inhibitor p27Kip1 was not affected by either PCB 126 or PCB 153. These results suggest that dioxin-like PCBs can induce cell proliferation of contact-inhibited rat liver epithelial cells by increasing cyclin A protein levels, a process that then leads to upregulation of cyclin A/cdk2 activity and initiation of DNA replication. This mechanism could be involved in tumor-promoting effects of dioxin-like PCBs. 相似文献
64.
M M Borner J Bernhard D Dietrich R Popescu M Wernli P Saletti D Rauch R Herrmann D Koeberle H Honegger P Brauchli D Lanz A D Roth 《Annals of oncology》2005,16(2):282-288
BACKGROUND: To determine the efficacy, impact on quality-of-life (QoL) and tolerability of two different irinotecan administration schedules in combination with capecitabine as first-line treatment of metastatic colorectal cancer. PATIENTS AND METHODS: We carried out a randomized phase II trial to select one of the following treatment regimens for further investigation: weekly irinotecan at a dose of 70 mg/m(2) days 1, 8, 15, 22, 29 (arm A) or 3-weekly irinotecan at a dose of 300/240 mg/m(2) day 1 and days 22 (arm B) in combination with capecitabine 1000 mg/m(2) twice daily days 1-14 and days 22-35 every 6 weeks. RESULTS: Seventy-five patients with good performance status entered the trial. The two arms were well balanced for relevant patient and disease characteristics. The most frequent toxic effects were grade 3/4 diarrhea (arm A: 34%, B: 19%), grade 3/4 neutropenia (A: 5%, B: 19%) and grade 2/3 alopecia (A: 26%, B: 65%). Other grade 3/4 toxic effects were rare (<5%). Response rates were 34% [95% confidence interval (CI) 20% to 51%] in arm A and 35% (95% CI: 20% to 53%) in arm B. Median time to progression was 6.9 (4.6-10.1) and 9.2 (7.9-11.5) months and median overall survival was 17.4 (12.6-23.0+) and 24.7 (16.3-26.4+) months. Patients with an objective tumor response reported better physical well-being (P < 0.01), mood (P < 0.05), functional performance (P < 0.05) and less effort to cope (P < 0.05) compared with the non-responders and stable disease patients. CONCLUSIONS: The primary end point of this study was the objective response rate and based on the statistical design of the trial, the 3-weekly irinotecan schedule was selected over weekly irinotecan administration. The 3-weekly irinotecan schedule also seemed advantageous in terms of grade 3/4 diarrhea, time to progression, overall survival and patient convenience, but the study was not designed to detect differences in these parameters. In addition, tumor response was shown to have a beneficial effect on QoL indicators. 相似文献
65.
Occurrence and elimination of cyanobacterial toxins in two Australian drinking water treatment plants. 总被引:3,自引:0,他引:3
In Australian freshwaters, Anabaena circinalis, Microcystis spp. and Cylindrospermopsis raciborskii are the dominant toxic cyanobacteria. Many of these surface waters are used as drinking water resources. Therefore, the National Health and Medical Research Council of Australia set a guideline for MC-LR toxicity equivalents of 1.3 microg/l drinking water. However, due to lack of adequate data, no guideline values for paralytic shellfish poisons (PSPs) (e.g. saxitoxins) or cylindrospermopsin (CYN) have been set. In this spot check, the concentration of microcystins (MCs), PSPs and CYN were determined by ADDA-ELISA, cPPA, HPLC-DAD and/or HPLC-MS/MS, respectively, in two water treatment plants in Queensland/Australia and compared to phytoplankton data collected by Queensland Health, Brisbane. Depending on the predominant cyanobacterial species in a bloom, concentrations of up to 8.0, 17.0 and 1.3 microg/l were found for MCs, PSPs and CYN, respectively. However, only traces (<1.0 microg/l) of these toxins were detected in final water (final product of the drinking water treatment plant) and tap water (household sample). Despite the low concentrations of toxins detected in drinking water, a further reduction of cyanobacterial toxins is recommended to guarantee public safety. 相似文献
66.
Krenn L Presser A Pradhan R Bahr B Paper DH Mayer KK Kopp B 《Journal of natural products》2003,66(8):1107-1109
A sulfated emodin glucoside, emodin 8-O-beta-D-glucopyranosyl-6-O-sulfate (1), was isolated from the roots of Rheum emodi in an investigation of the active constituents of this Nepalese medicinal plant, and its structure was determined by spectroscopic and chemical methods. Additionally, two rare auronols, carpusin (2) and maesopsin (3), besides other anthraquinones and phenolics, were isolated and identified. Compounds 2 and 3 showed significant antioxidant activity in the DPPH assay, while chrysophanol, physcion, and emodin and their 8-O-glucosides were found to be inactive. 相似文献
67.
M L Dietrich T F Dolnicek W F Rayburn 《American journal of obstetrics and gynecology》1987,156(6):1403-1408
This prospective investigation was undertaken to compare the value of routine versus selective diabetes screening in a group of predominantly middle-class, healthy, Caucasian pregnant women. Two thousand consecutively chosen persons were divided into two groups: those to undergo routine screening between 24 and 28 weeks' gestation and those to be tested selectively in the presence of standard risk factors. The two groups of patients were otherwise similar. The method of screening involved a 50 gm oral glucose challenge, followed by a 3-hour glucose test if necessary. The incidence of gestational onset diabetes in the selectively screened group (19/453, 4.2%) was twice that in the routinely screened group (21/1000, 2.1%). Evidence of glucose intolerance without a risk factor was found in only one case (1/1000, 0.1%) in the routinely screened group. This assessment of our clinical practice has allowed us to safely eliminate the need for diabetes screening in more than half of our private patients, which will reduce office time, patient inconvenience, and expense. 相似文献
68.
TRPC6 is a Ca(2+)-permeable non-selective cation channel expressed in brain, smooth muscle containing tissues and kidney, as well as in immune and blood cells. Channel homomers heterologously expressed have a characteristic doubly rectifying current-voltage relationship and are six times more permeable for Ca2+ than for Na+. In smooth muscle tissues, however, Na+ influx and activation of voltage-gated calcium channels by membrane depolarization rather than Ca2+ elevation by TRPC6 channels is the driving force for contraction. TRPC6 channels are directly activated by the second messenger diacylglycerol (DAG) and regulated by specific tyrosine or serine phosphorylation. Extracellular Ca2+ has inhibitory effects, while Ca2+/calmodulin acting from the intracellular side has potentiator effects on channel activity. Given its specific expression, TRPC6 is likely to play a number of physiological roles. Studies with TRPC6(-/-) mice suggest a role for the channel in the regulation of vascular and pulmonary smooth muscle contraction. TRPC6 was identified as an essential component of the slit diaphragm architecture of kidney podocytes. Other functions in immune and blood cells, as well as in brain and in smooth muscle-containing tissues such as stomach, colon and myometrium, remain elusive. 相似文献
69.
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