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排序方式: 共有1067条查询结果,搜索用时 31 毫秒
61.
Gregoire FM Zhang Q Smith SJ Tong C Ross D Lopez H West DB 《American journal of physiology. Endocrinology and metabolism》2002,282(3):E703-E713
The effects of high-fat feeding on the development of obesity were evaluated in intercellular adhesion molecule-1 (ICAM-1) knockout and C57BL/6J (B6) male mice fed a high-fat diet for < or =50 days. Serum and tissues were collected at baseline and after 1, 11, and 50 days on the diet. After 11 days on the diet, ICAM-1-deficient, but not B6, mice developed fatty livers and showed a significant increase in inguinal fat pad weight. At day 50, ICAM-1-deficient mice weighed less, and their adiposity index and circulating leptin levels were significantly lower than those of B6 controls. To better understand the early differential response to the diet, liver gene expression was analyzed at three time points by use of Affymetrix GeneChips. In both strains, a similar pattern of gene expression was detected in response to the high-fat diet. However, sterol regulatory element-binding protein-1, apolipoprotein A4, and adipsin mRNAs were significantly induced in ICAM-1-deficient livers, suggesting that these genes and their associated pathways may be involved in the acute diet response observed in the knockout mice. 相似文献
62.
Therapeutic efficacy of melanoma-reactive TIL injected in stage III melanoma patients 总被引:4,自引:0,他引:4
Labarrière N Pandolfino MC Gervois N Khammari A Tessier MH Dréno B Jotereau F 《Cancer immunology, immunotherapy : CII》2002,51(10):532-538
Adoptive therapy for cancer using tumor-infiltrating lymphocytes (TIL) has mainly been investigated in cancer patients with advanced stage disease. The limited clinical success has not been encouraging, although this might be explained by poor TIL specificity and/or high tumor burden. To re-evaluate the effectiveness of adoptive therapy, we analyzed the capacity of tumor-reactive TIL injection in preventing the further development of disease in stage III melanoma patients after complete tumor resection. A phase II/III randomized trial was performed on 88 melanoma patients, who received autologous TIL plus interleukin-2 (IL-2) or IL-2 only. The duration of relapse-free survival was analyzed, taking into account the immunological specificity of injected TIL and the number of metastatic lymph nodes removed before treatment. Kaplan-Meyer analysis revealed that the injection of tumor-reactive TIL was statistically correlated with prolonged relapse-free survival in patients with only one metastatic lymph node. Therefore, improved clinical outcome could be obtained after adoptive therapy by selecting appropriate groups of patients and monitoring the specificity of the injected TIL populations. 相似文献
63.
Optical trapping techniques provide unique means to manipulate biological particles such as virus, living cells and subcellular organelles. Another area of interest is the measurement of mechanical (elastic) properties of cell membranes, long strands of single DNA molecule, and filamentous proteins. One of the most attractive applications is the study of single motor molecules. With optical tweezers traps, one can measure the forces generated by single motor molecules such as kinesin and myosin, in the piconewton range and, for the first time, resolve their detailed stepping motion. 相似文献
64.
New perspectives of locomotor rehabilitation after stroke 总被引:1,自引:0,他引:1
The task-oriented approach incorporating treadmill walking for retraining gait early after stroke has contributed to promote locomotor recovery. To augment practice, training strategies such as mental practice and training in virtual environments are proposed. While the former offers more practice with less physical exertion, the latter allows safe practice in a variety of challenging environments. Work is under way to assess whether these new strategies can further enhance locomotor recovery. 相似文献
65.
The role of magnetic resonance imaging in the management of vascular malformations of the trunk and extremities 总被引:5,自引:0,他引:5
Rinker B Karp NS Margiotta M Blei F Rosen R Rofsky NM 《Plastic and reconstructive surgery》2003,112(2):504-510
Vascular malformations can usually be diagnosed on clinical grounds. They have a well-defined appearance on magnetic resonance imaging, which can effectively determine their tissue and flow characteristics. However, the role of cross-sectional imaging in the management of vascular malformations is not well defined. Most reviews suggest that magnetic resonance imaging should be reserved for cases in which the extent of the lesion cannot be estimated on physical examination. However, to date no group has compared the accuracy of physical examination alone to that of magnetic resonance imaging in determining this extent. A review was performed of all the patients evaluated for vascular malformations at the New York University Trunk and Extremity Vascular Anomalies Conference between July of 1994 and August of 1999. Patients who underwent magnetic resonance evaluation at other institutions and whose images were not available for review were excluded. All study patients either underwent magnetic resonance imaging examination at New York University Medical Center or had outside films reviewed at the center. The physical examination findings were compared with the magnetic resonance findings and the surgeon and radiologist made a joint decision about whether there was a correlation between the magnetic resonance and physical examination findings. Fifty-eight patients met the study criteria, 44 (76 percent) of whom were found to have more extensive disease on magnetic resonance examination than appreciated on physical examination. Of the 51 patients with low-flow vascular malformations (venous vascular malformations, lymphatic malformations, and capillary malformations), 39 (76 percent) had more extensive disease on magnetic resonance examination than on physical examination. Of the seven patients with high-flow arteriovenous malformations, five had more extensive disease on magnetic resonance. In all of the 44 patients whose magnetic resonance imaging findings did not correlate with those of the physical examination, therapeutic decision making was affected. Contrary to the conventional wisdom of published reviews, physical examination findings significantly underestimated the extent of vascular malformations in the majority of cases. Magnetic resonance imaging should be performed in all patients with vascular malformations of the trunk and extremities before therapy is planned. In an age when physicians are asked to justify their decisions, especially where the use of expensive diagnostic modalities is concerned, the situations in which these tests are indispensable must be clearly defined or else patients will be denied access to them. 相似文献
66.
Marciano-Cabral F MacLean R Mensah A LaPat-Polasko L 《Applied and environmental microbiology》2003,69(10):5864-5869
The free-living amoeboflagellate Naegleria fowleri is the causative agent of primary amoebic meningoencephalitis (PAM), a rapidly fatal disease of the central nervous system. In the United States, the disease is generally acquired while swimming and diving in freshwater lakes and ponds. In addition to swimming, exposure to N. fowleri and the associated disease can occur by total submersion in bathwater or small backyard wading pools. In the present study, swipe samples and residual pipe water from homes in Arizona were examined for N. fowleri by nested PCR due to the death of two previously healthy children from PAM. Since neither child had a history of swimming in a freshwater lake or pond prior to the onset of disease symptoms, the domestic water supply was the suspected source of infection. Of 19 samples collected from bathroom and kitchen pipes and sink traps, 17 samples were positive for N. fowleri by PCR. A sample from a Micro-Wynd II filter was obtained by passing water from bathtubs through the filter. Organisms attached to the filter also tested positive by PCR. The two samples that tested negative for N. fowleri were one that was obtained from a kitchen sink trap and a swipe sample from the garbage disposal of one home. 相似文献
67.
Optimal care for a subgroup of infants with complicated vascular anomalies requires prenatal diagnosis. Fetal vascular lesions are either vascular tumors or vascular malformations, both of which are often detected on routine ultrasound. Imaging, such as ultrasound and fetal MRI, can be used to examine lesions and provide the data for a differential diagnosis, which may impact the course of care both in utero and postnatally. Prenatal diagnosis provides the opportunity for antenatal intervention, parental counseling, and planning of the mode and location of delivery to optimize postnatal care. Prenatal diagnosis of vascular lesions also serves to alert the physician to the potential for associated syndromes and complications. Any indication of a vascular anomaly should be referred for further examination by an experienced multidisciplinary team of physicians to ensure the window in which evaluation, planning, and treatment can take place is not missed. 相似文献
68.
Molecular and Physiological Responses to Water Deficit in Drought-Tolerant and Drought-Sensitive Lines of Sunflower : Accumulation of Dehydrin Transcripts Correlates with Tolerance
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Fran?oise Cellier Geneviève Conéjéro Jean-Christophe Breitler Francine Casse 《Plant physiology》1998,116(1):319-328
69.
Objectives To estimate the therapeutic and adverse effects of addition of inhaled anticholinergics to β2 agonists in acute asthma in children and adolescents.Design Systematic review of randomised controlled trials of children and adolescents taking β2 agonists for acute asthma with or without the addition of inhaled anticholinergics.Main outcome measures Hospital admission, pulmonary function tests, number of nebulised treatments, relapse, and adverse effects.Results Of 37 identified trials, 10 were relevant and six of these were of high quality. The addition of a single dose of anticholinergic to β2 agonist did not reduce hospital admission (relative risk 0.93, 95% confidence interval 0.65 to 1.32). However, significant group differences in lung function supporting the combination treatment were observed 60 minutes (standardised mean difference −0.57, −0.93 to −0.21) and 120 minutes (−0.53, −0.90 to −0.17) after the dose of anticholinergic. In contrast, the addition of multiple doses of anticholinergics to β2 agonists, mainly in children and adolescents with severe exacerbations, reduced the risk of hospital admission by 30% (relative risk 0.72, 0.53 to 0.99). Eleven (95% confidence interval 5 to 250) children would need to be treated to avoid one admission. A parallel improvement in lung function (standardised mean difference −0.66, −0.95 to −0.37) was noted 60 minutes after the last combined inhalation. In the single study where anticholinergics were systematically added to every β2 agonist inhalation, irrespective of asthma severity, no group differences were observed for the few available outcomes. There was no increase in the amount of nausea, vomiting, or tremor in patients treated with anticholinergics.Conclusions Adding multiple doses of anticholinergics to β2 agonists seems safe, improves lung function, and may avoid hospital admission in 1 of 11 such treated patients. Although multiple doses should be preferred to single doses of anticholinergics, the available evidence only supports their use in school aged children and adolescents with severe asthma exacerbation.
Key messages
- The addition of multiple doses of anticholinergics to β2 agonist inhalations seems indicated in the initial management of children and adolescents with severe exacerbations of asthma (⩽55% of predicted FEV1)
- For the larger group of children and adolescents with mild to moderate asthma exacerbations, there is no apparent benefit from adding a dose of anticholinergics to β2 agonists
- Little evidence exists to support the systematic addition of anticholinergics to every β2 agonist inhalation, irrespective of patients’ disease severity
70.