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排序方式: 共有1013条查询结果,搜索用时 15 毫秒
1.
Yuval Dror 《Child & youth care forum》1995,24(3):195-208
Internal totality and community orientation are two pivotal components, difficult to measure, in the literature on residential education (including both residential schools for the elite and group or congregate care and education programs for marginal youth). We propose a two-dimensional model based on historical research and contemporary study to define and differentiate these concepts. Internal totality can be measured through the links and balance between the formal curriculum, extra curriculum, and out of school (nonformal) activities; community orientation through links between the residential and ideological community, the local community, and the wider community. Implications for practice, policy, and further research are suggested.Oranim is the School of Education of the Kibbutz Movement, affiliated with the University of Haifa. 相似文献
2.
Y Dror Y Blachar P Cohen N Livni E Rosenmann A Ashkenazi 《American journal of kidney diseases》1998,32(5):825-828
Systemic lupus erythematosus (SLE) is a multisystem disease of unknown origin, characterized by a variety of autoimmune phenomena. Viruses have long been postulated to play a role in its pathogenesis. Several observations suggested a link between Epstein-Barr virus (EBV) and SLE. We describe a 14-year-old girl who presented with acute onset of SLE concurrently with clinical and laboratory findings consistent with EBV-induced infectious mononucleosis (IM). Evidence for acute EBV infection was confirmed by serological studies and detection of specific EBV antigens on kidney biopsy. This close association between EBV and SLE suggests a possible role of the virus in the pathogenesis of SLE in this patient. 相似文献
3.
Dynamic Mechanical Conditioning of Collagen-Gel Blood Vessel Constructs Induces Remodeling In Vitro 总被引:11,自引:0,他引:11
Dynamic mechanical conditioning is investigated as a means of improving the mechanical properties of tissue-engineered blood vessel constructs composed of living cells embedded in a collagen-gel scaffold. This approach attempts to elicit a unique response from the embedded cells so as to reorganize their surrounding matrix, thus improving the overall mechanical stability of the constructs. Mechanical conditioning, in the form of cyclic strain, was applied to the tubular constructs at a frequency of 1 Hz for 4 and 8 days. The response to conditioning thus evinced involved increased contraction and mechanical strength, as compared to statically cultured controls. Significant increases in ultimate stress and material modulus were seen over an 8 day culture period. Accompanying morphological changes showed increased circumferential orientation in response to the cyclic stimulus. We conclude that dynamic mechanical conditioning during tissue culture leads to an improvement in the properties of tissue-engineered blood vessel constructs in terms of mechanical strength and histological organization. This concept, in conjunction with a proper biochemical environment, could present a better model for engineering vascular constructs. © 2000 Biomedical Engineering Society.
PAC00: 8719Rr, 8714Ee, 8718-h, 8768+z 相似文献
4.
Einat Rabinovitch Dror Harats Pnina Yaron Tamar Luvish Merav Lidar Ron Kedem Aviv Shaish Issahar Ben-Dov Avi Livneh 《Annals of allergy, asthma & immunology》2007,99(6):517-521
BACKGROUND: Asthma is an inflammatory airway disease caused by interaction between susceptibility genes and diverse environmental factors. In Israel, asthma seems to be familial and more severe in patients of Iraqi Jewish descent. On the other hand, asthma is less frequent in individuals with familial Mediterranean fever, an autoinflammatory disease prevalent in the Iraqi Jewish community and linked to mutations in the familial Mediterranean fever gene, designated MEFV. OBJECTIVES: To explore a possible role for mutated MEFV in the reduced susceptibility to asthma and to determine its expression in Israeli subjects of Iraqi origins. METHODS: Using a case-control approach, we studied the presence of the 3 most common MEFV mutations (M694V, V726A, and E148Q) in DNA samples from 75 patients with asthma and 45 asymptomatic first-degree relatives, all of Iraqi Jewish origin. The severity of asthma was evaluated using a published severity score. RESULTS: Eleven patients with asthma and 14 of their relatives carried 1 or 2 mutations in the MEFV gene, a carrier rate significantly lower in patients with asthma than in their first-degree relatives and in ethnically matched healthy individuals (P < .03 and P < .003, respectively). Carriers of MEFV mutations had less severe disease, compared with noncarriers (P < .002). CONCLUSION: These findings suggest that MEFV mutations may have a protective effect in the pathogenesis of asthma. 相似文献
5.
Pnina Fishman Emily Falach-Vaknin Benjamin Sredni Piere Luigi Meroni Angela Tincani Dror Dicker Yehuda Shoenfeld 《American journal of reproductive immunology (New York, N.Y. : 1989)》1996,35(2):80-84
PROBLEM: Previously we reported on the generation of experimental anti-phospholipid syndrome (APS) in mice. These models were employed to evaluate the efficacy of various novel therapeutic modalities including interleukin-3 (IL-3) and low dose aspirin. The efficacy of the latter was found to be interrelated. Low dose aspirin is capable of inhibiting the activity of the enzyme cyclooxygenase which is responsible for the metabolism of arachidonic acid towards the production of prostaglandins. This shifts the metabolism of arachidonic acid to the other pathway and leads to an overproduction of leukotrienes. The leukotrienes act as stimulators of IL-3 production, a positive cytokine in pregnancy which enhances placental and fetal development. In the current study we evaluated the IL-3 levels in pregnant women with APS and expanded our knowledge on the interrelationships between aspirin, arachidonic acid metabolites and IL-3 in the human system. METHODS: IL-3 levels were recorded in the serum of pregnant women with APS and compared to a control pregnant group. In addition peripheral blood mononuclear cells from healthy subjects were incubated with different concentrations of aspirin or with arachidonic acid metabolites (Leukotriene B4, C4 or PGE2), and IL-3 production in the culture fluids was evaluated. RESULTS: Serum level of IL-3 in pregnant patients with primary APS, APS secondary to SLE and SLE was lower in comparison to the control group. The in vitro studies revealed that only low dose aspirin (10 mg/μl) stimulated IL-3 production while higher doses of the drug failed to induce the cytokine generation. Leukotriene B4 and C4 were stimulatory whereas PGE2 acted as inhibitor of IL-3 production. CONCLUSIONS: The serum level of IL-3 is decreased to pregnant women with primary or secondary APS. Low dose aspirin is capable of stimulating EL-3 production in vitro most probably through an elevation of leukotriene production, which may explain its beneficial activity in preventing the manifestations of APS. 相似文献
6.
7.
Back reflection losses are a key problem that limits the performances of optical communication systems that work on wavelength division multiplexing (WDM) technology based on silicon (Si) Multimode Interference (MMI) waveguides. In order to overcome this problem, we propose a novel design for a 1 × 4 optical demultiplexer based on the MMI in silicon nitride (SiN) buried waveguide structure that operates at the C-band spectrum. The simulation results show that the proposed device can transmit four channels with a 10 nm spacing between them that work in the C-band with a low power loss range of 1.98–2.35 dB, large bandwidth of 7.68–8.08 nm, and good crosstalk of 20.9–23.6 dB. Thanks to the low refractive index of SiN, a very low back reflection of 40.57 dB is obtained without using a special angled MMI design, which is usually required, using Si MMI technology. Thus, this SiN demultiplexer MMI technology can be used in WDM technique for obtaining a high data bitrate alongside a low back reflection in optical communication systems. 相似文献
8.
Are triglyceride-rich lipoproteins associated with aortic valve sclerosis? A preliminary report 总被引:2,自引:0,他引:2
Background: Evidence linking cardiovascular risk factors to aortic valve sclerosis (AVS) has led to the assumption that the latter is an atherosclerosis-like process. However, triglyceride (TG)-rich lipoproteins, an important risk factor for atherosclerosis, have been rarely investigated in connection with AVS. Methods: A cross-sectional study of 246 healthy individuals (mean age 59±6 years, 77% men) was conducted. Subjects underwent an echocardiographic assessment and extensive blood lipid measurements, including evaluation of TG-related indices, such as serum apolipoprotein (apo) CII and CIII levels, apo CIII levels in VLDL+LDL particles, and apo CIII ratio (CIII level in HDL/CIII level in VLDL+LDL). Results: Twenty-three patients (9.3%) were diagnosed as having AVS. On average, these patients were 5 years older and had higher levels of serum cholesterol, LDL-C and LP(a), compared with non-AVS subjects. In addition, the AVS patients exhibited higher concentrations of serum apo CII, serum apo CIII and apo CIII in VLDL+LDL, and a lower apo CIII ratio. Adjusting for age and gender, a 1 S.D. increment in apo CIII in VLDL+LDL was associated with odds ratio (OR) of 1.76 (95% CI: 1.17–2.65) for AVS. Further adjustment for atherosclerotic risk factors did not alter the association appreciably (OR=1.65, 95% CI: 1.06–2.58). Conclusion: TG-rich lipoproteins may be involved in the early development of AVS. Confirmation in prospective studies is required. 相似文献
9.
Maciej Cabanski Brett Fields Stephanie Boue Natalia Boukharov Hector DeLeon Natalie Dror Marcel Geertz Emmanuel Guedj Anita Iskandar Ulrike Kogel Celine Merg Michael J. Peck Carine Poussin Walter K. Schlage Marja Talikka Nikolai V. Ivanov Julia Hoeng Manuel C. Peitsch 《Inflammation research》2015,64(7):471-486
10.
Viskoper R Shapira I Priluck R Mindlin R Chornia L Laszt A Dicker D Gavish B Alter A 《American journal of hypertension》2003,16(6):484-487
BACKGROUND: Recent studies have demonstrated the antihypertensive effect of slow breathing exercises, guided interactively by a device, in patients with uncontrolled blood pressure (BP) without changing medication. This study examined the response to the same treatment protocol in resistant hypertensives. METHODS: Seventeen resistant hypertensives exercised device-guided slow breathing for 8 weeks, 15 min daily, and self-monitored BP. Data stored in the devices were collected on a PC-based system. Clinical outcomes were office and home BP changes from baseline to end values. RESULTS: Significant reductions in both office BP (-12.9/-6.9 mm Hg, P <.001 and home BP (-6.4/-2.6 mm Hg, P <.01/P <.05) without side effects with 82% responders and good compliance. CONCLUSIONS: Resistant hypertensives can benefit from and are compliant with self-treatment by device-guided slow breathing. 相似文献