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991.
Fluorescence is increasingly used for in vivo imaging and has provided remarkable results. Yet this technique presents several limitations, especially due to tissue autofluorescence under external illumination and weak tissue penetration of low wavelength excitation light. We have developed an alternative optical imaging technique by using persistent luminescent nanoparticles suitable for small animal imaging. These nanoparticles can be excited before injection, and their in vivo distribution can be followed in real-time for more than 1 h without the need for any external illumination source. Chemical modification of the nanoparticles' surface led to lung or liver targeting or to long-lasting blood circulation. Tumor mass could also be identified on a mouse model.  相似文献   
992.
In industrialized countries there is a high prevalence of allergy toward nickel ions. The exposure of affected individuals to nickel leads to a delayed-type hypersensitivity reaction, which is induced by antigen-specific CD4 and CD8 T cells. Beside this antigenic potential, immunomodulatory properties of nickel ions were described. To dissect the role of both mechanisms for HIV replication, we studied HIV expansion in PBMC of nickel-allergic and nonallergic donors. Nickel ions promote HIV replication in PBMC as efficiently as protein antigens. The nickel-mediated virus expansion strictly required the presence of nickel-specific T cells. Data obtained with nickel-specific CD4 T cell clones showed that antigen-mediated proliferation is an absolute prerequisite for HIV expansion. However, the previously suggested immunomodulatory properties of nickel ions do not seem to contribute to HIV expansion. As a widely distributed antigen with increasing numbers of allergic people, nickel may be an important and underestimated factor of HIV expansion in vivo.  相似文献   
993.
994.
Some radiological cases are presented in this article to train the reader to the BIRADS classification in mammography. Each case is described according to the fourth American version of the BIRADS lexicon. Some classifications difficulties will also be presented, in order to show the complexity and the observer variability, commonly encountered in BIRADS 3 and 4 categories.  相似文献   
995.
We report a case of an 18‐month‐old female who presented an occipital bone lesion with progressive growth. Imaging studies showed a left extradural, skull‐based tumor partially occupying the posterior fossa. Histopathological and immunohistochemical studies confirmed a juvenile xanthogranuloma (JXG). Partial surgical resection, chemotherapy, and conformational radiotherapy were used. Exclusive extracutaneous JXG with an intracranial, vertebral, or skull‐based localization is extremely rare. Pediatr Blood Cancer. 2010;55:380–382. © 2010 Wiley–Liss, Inc.  相似文献   
996.

Context:

Social support has been identified as an important factor in facilitating recovery from injury. However, no previous authors have prospectively assessed the change in social support patterns before and after injury.

Objective:

To examine the preinjury and postinjury social support patterns among male and female collegiate athletes.

Design:

Prospective observational study.

Setting:

A Big Ten Conference university.

Patients or Other Participants:

A total of 256 National Collegiate Athletic Association Division I male and female collegiate athletes aged 18 or older from 13 sports teams.

Main Outcome Measure(s):

Injury incidence was identified using the Sports Injury Monitoring System. Social support was measured using the 6-item Social Support Questionnaire. Data on preinjury and postinjury social support patterns were compared.

Results:

Male athletes reported more sources of social support than female athletes, whereas female athletes had greater satisfaction with the support they received. Athletes'' social support patterns changed after they became injured. Injured athletes reported relying more on coaches (P  =  .003), athletic trainers (P < .0001), and physicians (P  =  .003) for social support after they became injured. Athletes also reported greater postinjury satisfaction with social support received from friends (P  =  .019), coaches (P  =  .001), athletic trainers (P < .0001), and physicians (P  =  .003).

Conclusions:

Our findings identify an urgent need to better define the psychosocial needs of injured athletes and also strongly suggest that athletic trainers have a critical role in meeting these needs.  相似文献   
997.
Mutations of LAMB2 typically cause autosomal recessive Pierson syndrome, a disorder characterized by congenital nephrotic syndrome, ocular and neurologic abnormalities, but may occasionally be associated with milder or oligosymptomatic disease variants. LAMB2 encodes the basement membrane protein laminin β2, which is incorporated in specific heterotrimeric laminin isoforms and has an expression pattern corresponding to the pattern of organ manifestations in Pierson syndrome. Herein we review all previously reported and several novel LAMB2 mutations in relation to the associated phenotype in patients from 39 unrelated families. The majority of disease‐causing LAMB2 mutations are truncating, consistent with the hypothesis that loss of laminin β2 function is the molecular basis of Pierson syndrome. Although truncating mutations are distributed across the entire gene, missense mutations are clearly clustered in the N‐terminal LN domain, which is important for intermolecular interactions. There is an association of missense mutations and small in frame deletions with a higher mean age at onset of renal disease and with absence of neurologic abnormalities, thus suggesting that at least some of these may represent hypomorphic alleles. Nevertheless, genotype alone does not appear to explain the full range of clinical variability, and therefore hitherto unidentified modifiers are likely to exist. Hum Mutat 31:992–1002, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
998.
Interstitial deletions involving the 15q21.1 band are very rare. Only 4 of these cases have been studied using molecular cytogenetic techniques in order to confirm the deletion of the whole FBN1 gene. The presence of clinical features of the Marfan syndrome (MFS) spectrum associated with mental retardation has been described in only 2/4 patients. Here we report on a 16-year-old female referred for suspicion of MFS (positive thumb and wrist sign, scoliosis, joint hyperlaxity, high-arched palate with dental crowding, dysmorphism, mitral insufficiency with dystrophic valve, striae). She had therefore 3 minor criteria according to the Ghent nosology. She also had speech disabilities but could follow normal school training. Direct sequencing of the FBN1, TGFBR1 and TGFBR2 genes was negative. MLPA revealed a genomic deletion of the whole FBN1 gene, confirmed by loss of heterozygosity of maternal alleles for several microsatellite markers surrounding the FBN1 gene. The deletion was confirmed by FISH using a FBN1 probe and was not found in the parents. Array-CGH permitted to define a 2.97 Mb deletion, which was the smallest 15q microdeletion including FBN1. Contrary to the other published observations, our proband does not exhibit mental retardation, but neuropsychological evaluations revealed an attention deficit as well as a deficit in information-processing speed. Haploinsufficiency of FBN1 is likely to contribute to the presence of MFS features. However, attenuated features could be explained because disturbances of TGF-β signalling associated with FBN1 mutations do not exert full phenotypic effect through simple haploinsufficiency. Phenotypic variability in other patients with interstitial deletions including 15q21.1 band may reflect differences in deletion size and/or cys/trans modifying factors.  相似文献   
999.
OBJECTIVES: We sought to evaluate epidemiology, clinical features, and outcomes of patients with syncope and an abnormal response to adenosine triphosphate (ATP). BACKGROUND: Syncope remains of unknown origin in almost 30% of the patients. Injection of ATP induces in some of these patients, but not in control patients, a ventricular pause > or =6 s. METHODS: Patients with syncope of unknown origin had an intravenous injection of 20 mg of ATP. All patients had a tilt test. RESULTS: Among 214 patients, 19 (8.9%) had a positive ATP test result. The proportion of positive test results was higher (p < 0.002) in women (14.3%) than in men (2.2%). Ten patients (4.7%) had positive ATP and tilt test results. These patients (exclusively women) were older (p < 0.05) at the time of their fist syncope than the 67 patients with a negative ATP test result but a positive tilt test result. There was a trend for these two test results to be correlated (p = 0.07). Side effects were of short duration and benign. The mean duration of pauses was longer in women (p = 0.009). During a mean period of 31 +/- 14 months, recurrences of syncope were reported in 25% of patients. CONCLUSIONS: The ATP test is a safe test with an "abnormal" result in <10% of patients with syncope of unknown origin. The profile of these patients is characteristic.  相似文献   
1000.
BACKGROUND: Detrimental effects of consumption of industrial trans fatty acids (TFA) from partially hydrogenated vegetable oils (PHVO) on cardiovascular disease (CVD) risk factors are well documented. However, very little information is available on the effect of natural sources of TFA coming from milk fat, dairy products and ruminant meat. In fact, due to the naturally low level of TFA in milk fat, it is almost impossible to conduct a clinical trial with a limited number of subjects (<200). METHODOLOGY: To compare the effects of industrial and natural dietary sources of TFA, two specific test fats have been designed and produced. A substantial amount of milk fat (130 kg) enriched in TFA has been produced by modification of the cow's diet and selection of cows with the highest TFA content. The level obtained was approximately 4- to 7-fold higher than typically present in milk fat (approximately 20 instead of 3-6 g/100 g of total fatty acids). The control fat is composed of PHVO balanced in saturated fatty acids (lauric, myristic and palmitic). Both experimental fats contain about 20-22% of monounsaturated TFA and the volunteers' daily experimental fat intake (54 g), will represent about 12.0 g/day of TFA or 5.4% of the daily energy (based on 2000 kcal/day). These two test fats have been incorporated into food items and will be provided to 46 healthy subjects under a randomised, double blind, controlled, cross-over design. The primary outcome is high-density lipoprotein cholesterol (HDL-C), which is an independent risk factor for CVD. Other parameters such as low-density lipoprotein cholesterol (LDL-C), very low-density lipoprotein cholesterol (VLDL-C), and HDL-C level and subclasses will be also to be evaluated. CONCLUSION: We have shown that it is technically feasible to perform a clinical trial on the comparative effects of natural and industrial sources of TFA isomers on CVD risk factors. Results are expected by mid-2006.  相似文献   
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