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排序方式: 共有365条查询结果,搜索用时 31 毫秒
51.
52.
MR Afify Abd El-Moneim S Ali Fatma AF Turky 《Asian Pacific Journal of Tropical Biomedicine》2012,2(1):24-30
Objective
To evaluate the acaricidal activity of extracts of three essential oils of chamomile, marjoram and Eucalyptus against Tetranychus urticae (T. urticae) Koch.Methods
Extracts of three essential oils of chamomile, marjoram and Eucalyptus with different concentrations (0.5%, 1.0%, 2.0%, 3.0% and 4.0%) were used to control T. urticae Koch.Results
The results showed that chamomile (Chamomilla recutita) represented the most potent efficient acaricidal agent against Tetranychus followed by marjoram (Marjorana hortensis) and Eucalyptus. The LC50 values of chamomile, marjoram and Eucalyptus for adults were 0.65, 1.84 and 2.18, respectively and for eggs 1.17, 6.26 and 7.33, respectively. Activities of enzymes including glutathione-S-transferase, esterase (α-esterase and β-esterase) and alkaline phosphatase in susceptible mites were determined and activities of enzymes involved in the resistance of acaricides were proved. Protease enzyme was significantly decreased at LC50 of both chamomile and marjoram compared with positive control. Gas chromatography-mass spectrometer (GC-MS) proved that the major compositions of Chamomilla recutita are α-bisabolol oxide A (35.251%), and trans-β-farersene (7.758%), while the main components of Marjorana hortensis are terpinene-4-ol (23.860%), p-cymene (23.404%) and sabinene (10.904%).Conclusions
It can be concluded that extracts of three essential oils of chamomile, marjoram and Eucalyptus possess acaricidal activity against T. urticae. 相似文献53.
Etienne Cavalier Véronique Huberty Catherine Cormier Jean‐Claude Souberbielle 《Journal of bone and mineral research》2011,26(2):434-436
We have recently observed an increasing number of patients presenting very high serum levels of 25‐hydroxyvitamin D [25(OH)D] (> 150 ng/mL), which, in all cases, had been measured with the IDS EIA kit adapted on different “open” automated platforms. We performed a comparison between the IDS EIA kit adapted on two different “open”automated platforms and the DiaSorin RIA. We found a systematic bias (higher levels with the IDS EIA kit) for concentrations more than 50–60 ng/mL that was less obvious when the IDS EIA was used in its manual procedure. We thus suggest to use the IDS EIA kit in its manual procedure rather than to adapt it on an automated platform, and to interpret cautiously a 25(OH)D greater than 100 ng/mL with this kit. © 2011 American Society for Bone and Mineral Research. 相似文献
54.
胸腺肽α1(Tα1)为一种免疫调节多肽,可增强效应T细胞反应。此项大型随机试验主要评价了Tα1与达卡巴嗪(DTIC)和干扰素α(IFN—α)对于转移性黑色素瘤患者的疗效和安全性。 相似文献
55.
Objectives
To analyze the concept of “case series” in the medical literature compared with case reports.Methods
A PubMed search for articles published during 2009 which had “case series” in their title was performed. A total number of 621 articles were retrieved. 586 papers were included in the analysis and 35 were excluded (18 were commentary letters, 5 were not in English, and twelve could not be retrieved by our Library). The number of patients and category of these articles were analyzed.Results
The median (range) of the number of cases of articles having “case series” in their title was 7 (1–6432) cases. 186/ 586 articles had less than 5 cases (31.7%, 95% CI (28.3–35.1%)). The median (range) of the number of cases of articles having “case report” as their publication type was 4 (1–178) cases. Out of the 219 articles categorized as case reports 114 (52.1%, 95% CI (45.6–58.6%)) had less than five cases.Conclusions
The concept of “case series” is not well defined in the literature and does not reflect a specific research design. We suggest that a case series should have more than four patients while four paitents or less should be reported individually as case reports. 相似文献56.
Ridgers ND Saint-Maurice PF Welk GJ Siahpush M Huberty J 《The Journal of school health》2011,81(9):545-551
BACKGROUND: School recess provides a daily opportunity for physical activity engagement. The purpose of this study was to examine physical activity levels during recess by gender, ethnicity, and grade, and establish the contribution of recess to daily school physical activity levels. METHODS: Two hundred and ten children (45% boys) from grades 3 to 6 in 4 elementary schools had their physical activity during school quantified using uni‐axial accelerometry every 5 seconds for 5 consecutive school days. Data were collected in fall 2009. The proportion of time spent engaged in physical activity during daily school recess was determined using existing age‐appropriate cutpoints. The relative contribution of recess to school day physical activity was also determined. RESULTS: Boys were more active than girls during recess. Girls engaged in more sedentary activity than boys. No main effects for ethnicity were observed. Children in grades 3 and 5 were more active than children in grades 4 and 6. Recess contributed 17.9% and 15.5% toward boys' and girls' school day moderate‐to‐vigorous physical activity, respectively. CONCLUSION: Children engaged in physical activity during recess, though interventions may be needed to increase the intensity of activity in this context. 相似文献
57.
Development of the Child Attitude Toward Illness Scale 总被引:10,自引:3,他引:10
Described the development of the Child Attitude Toward IllnessScale (CATIS), a short self-report instrument designed to providea systematic assessment of how favorably or unfavorably childrenfeel about having a chronic physical condition. Subjects werechildren (N = 269), ages 812 years, who had either epilepsy(n = 136) or asthma (n = 133). Results of confirmatory factoranalysis and predicted relationships with scores on the ChildBehavior Checklist and the Piers-Harris Children's Self-ConceptScale provided support for construct validity of the scale.Good internal consistency and test-retest reliability were alsofound. 相似文献
58.
NJ Lees AJP Rosenberg AI Hurtado-Doce J Jones N Marczin M Zeriouh A Weymann A Sabashnikov AR Simon AF Popov 《Journal of artificial organs》2016,19(4):399-402
Sepsis-induced cardiogenic shock in combination with severe acute respiratory failure represents a life-threatening combination that is often refractory to the conventional methods of treatment. We describe the case of a 33-year-old patient who developed acute cardiovascular collapse and ARDS secondary to superinfection of Panton–Valentine leukocidin—positive Staphylococcus aureus and H1N1 pneumonia who underwent successful combination therapy for severe sepsis-related cardiomyopathy and respiratory failure using extracorporeal membrane oxygenation and cytokine adsorption therapy. 相似文献
59.
Invasion and Intracellular Development of the Human Granulocytic Ehrlichiosis Agent in Tick Cell Culture 总被引:9,自引:0,他引:9 下载免费PDF全文
Ulrike G. Munderloh Steven D. Jauron Volker Fingerle Lorenz Leitritz S. Fred Hayes Joan M. Hautman Curtis M. Nelson Brent W. Huberty Timothy J. Kurtti Gilbert G. Ahlstrand Barbara Greig Martha A. Mellencamp Jesse L. Goodman 《Journal of clinical microbiology》1999,37(8):2518-2524
Human granulocytotropic ehrlichias are tick-borne bacterial pathogens that cause an acute, life-threatening illness, human granulocytic ehrlichiosis (HGE). Ehrlichias within neutrophil granulocytes that invade tick bite sites are likely ingested by the vector, to be transmitted to another mammalian host during the tick's next blood meal. Thus, the cycle of replication and development in the vector is prerequisite to mammalian infection, and yet these events have not been described. We report tick cell culture isolation of two strains of the HGE agent directly from an infected horse and a dog and have also established a human isolate from HL60 culture in tick cells, proving that the blood stages of the HGE agent are infectious for tick cells, as are those replicating in the human cell line HL60. This required changes to the culture system, including a new tick cell line. In tick cell layers, the HGE agent induced foci of infection that caused necrotic plaques and eventual destruction of the culture. Using the human isolate and electron microscopy, we monitored adhesion, internalization, and replication in vector tick cells. Both electron-lucent and -dense forms adhered to and entered cells by a mechanism reminiscent of phagocytosis. Ehrlichial cell division was initiated soon after, resulting in endosomes filled with numerous ehrlichias. During early development, pale ehrlichias with a tight cell wall dominated, but by day 2, individual bacteria condensed into dark forms with a rippled membrane. These may become compacted into clumps where individual organisms are barely discernible. Whether these are part of an ehrlichia life cycle or are degenerating is unknown. 相似文献