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101.
A standard atlas space with stereotaxic co-ordinates for the postnatal day 0 (P0) C57BL/6J mouse brain was constructed from
the average of eight individual co-registered MR image volumes. Accuracy of registration and morphometric variations in structures
between subjects were analyzed statistically. We also applied this atlas coordinate system to data acquired using different
imaging protocols as well as to a high-resolution histological atlas obtained from separate animals. Mapping accuracy in the
atlas space was examined to determine the applicability of this atlas framework. The results show that the atlas space defined
here provides a stable framework for image registration for P0 normal mouse brains. With an appropriate feature-based co-registration
strategy, the probability atlas can also provide an accurate anatomical map for images acquired using invasive imaging methods.
The atlas templates and the probability map of the anatomical labels are available at . 相似文献
102.
The induction of autoimmunity by viruses has been hypothesized to occur by a number of mechanisms. Coxsackievirus B4 (CB4) induces hyperglycemia in SJL mice resembling diabetes in humans. While virus is effectively cleared within 2 weeks, hyperglycemia does not appear until about 8-12 weeks postinfection at a time when replicative virus is no longer detectable. In SJL mice, reinfection with CB4 enhanced the development of hyperglycemia. As predicted, the immune system responded more rapidly to the second infection and virus was cleared more swiftly. However, while infiltrating T cells were found within the pancreas, depletion of the CD4 T cell population prior to secondary infection or use of CD8 knock-out mice had no effect on the development of virus-mediated hyperglycemia. In conclusion, enhanced hyperglycemia induced by CB4 occurs independent of the T cell response. 相似文献
103.
The polarization properties of light scattered in a lateral direction from turbid media were studied. Polarization modulation and synchronous detection were used to measure, and Mueller calculus to model and derive, the degrees of surviving linear and circular polarization and the optical rotation induced by turbid samples. Polystyrene microspheres were used as scatterers in water solutions containing dissolved chiral, racemic, and achiral molecules. The preservation of circular polarization was found to exceed the linear polarization preservation for all samples examined. The optical rotation induced increased with the chiral molecule concentration only, whereas both linear and circular polarizations increased with an increase in the concentrations of chiral, racemic, and achiral molecules. This latter effect was shown to stem solely from the refractive index matching mechanism induced by the solute molecules, independent of their chiral nature. 相似文献
104.
Mohammad A. Karim Koji Suzuki Kazuyoshi Fukai Jangsuk Oh Deborah L. Nagle Karen J. Moore Ernest Barbosa Tzipora Falik‐Borenstein Alexandra Filipovich Yasushi Ishida Sirpa Kivrikko Christoph Klein Friedmar Kreuz Alex Levin Hiroaki Miyajima Jose R. Regueiro Carolyn Russo Eiichiro Uyama Outi Vierimaa Richard A. Spritz 《American journal of medical genetics. Part A》2002,108(1):16-22
Chediak‐Higashi syndrome (CHS) is a rare autosomal recessive disorder characterized by severe immunologic defects, reduced pigmentation, bleeding tendency, and progressive neurological dysfunction. Most patients present in early childhood and die unless treated by bone marrow transplantation. About 10–15% of patients exhibit a much milder clinical phenotype and survive to adulthood, but develop progressive and often fatal neurological dysfunction. Very rare patients exhibit an intermediate adolescent CHS phenotype, presenting with severe infections in early childhood, but a milder course by adolescence, with no accelerated phase. Here, we describe the organization and genomic DNA sequence of the CHS1 gene and mutation analysis of 21 unrelated patients with the childhood, adolescent, and adult forms of CHS. In patients with severe childhood CHS, we found only functionally null mutant CHS1 alleles, whereas in patients with the adolescent and adult forms of CHS we also found missense mutant alleles that likely encode CHS1 polypeptides with partial function. Together, these results suggest an allelic genotype–phenotype relationship among the various clinical forms of CHS. © 2002 Wiley‐Liss, Inc. 相似文献
105.
Anne R Nedrow Margaret Heitkemper Moshe Frenkel Douglas Mann Peter Wayne Ellen Hughes 《Academic medicine》2007,82(10):962-966
An effort to increase the understanding of complementary and alternative medicine (CAM) by health care professionals requires an interdisciplinary and collaborative approach. Between 2000 and 2002, National Institutes of Health National Center for Complementary and Alternative Medicine funded 15 educational institutions to develop curricular models for educating allopathic medical and nursing learners in CAM literacy. Four of these 15 programs, Tufts University School of Medicine, University of California at San Francisco School of Medicine, Oregon Health & Sciences University School of Medicine, and University of Washington School of Nursing, formed collaborative partnerships with nearby academic institutions that train CAM practitioners.This article focuses on these four examples of institutional collaboration, summarizing the challenges faced and the positive outcomes achieved for learners, faculty, and institutions. As collaborations between such institutions increase, future potential directions for consideration include credentialing of CAM practitioners teaching within allopathic health professional institutions, faculty development within existing allopathic health professional schools on incorporating evidence-based CAM content into their standard allopathic education, and viewing CAM as an aspect of cultural sensitivity. 相似文献
106.
Taki Y Goto R Evans A Zijdenbos A Neelin P Lerch J Sato K Ono S Kinomura S Nakagawa M Sugiura M Watanabe J Kawashima R Fukuda H 《Neurobiology of aging》2004,25(4):455-463
The objectives of this study were to evaluate the correlations of the volumes of the gray matter and white matter with age, and the correlations of the tissue probabilities of the gray matter and white matter with age and several cerebrovascular risk factors. We obtained magnetic resonance (MR) images of the brain and clinical information from 769 normal Japanese subjects. We processed the MR images automatically by correcting for inter-individual differences in brain size and shape, and by segmenting the MR images into the gray matter and white matter. Volumetry of the brain revealed a significant negative correlation between the gray matter volume and age, which was not observed between white matter volume and age. Voxel-based morphometry showed that age, systolic blood pressure, and alcohol drinking correlated with the regional tissue probabilities of the gray matter and white matter. 相似文献
107.
Moshe Swissa Shengmei Zhou Alex Y Tan Michael C Fishbein Peng-Sheng Chen Lan S Chen 《Cardiovascular pathology》2008,17(5):303-308
BACKGROUND: Subthreshold electrical stimulation of the left stellate ganglion (LSG) can induce nerve sprouting and sympathetic hyperinnervation in canine ventricles. It is unclear whether a similar neural plasticity involving both sympathetic and parasympathetic innervation also exists in the atria. METHODS AND RESULTS: We applied subthreshold electrical stimulation at 20 Hz (0.45 ms pulse width) or 5 Hz (1.9 ms pulse width) to the LSG in 6 normal mongrel dogs. After 41+/-9 days, the hearts were harvested and the right and left atrium stained for synaptophysin (SYN), growth-associated protein 43 (GAP43), sympathetic nerve markers tyrosine hydroxylase (TH), and parasympathetic marker choline acetyltransferase (ChAT). Tissues from 6 additional healthy dogs were used as controls. The hearts from dogs with LSG electrical stimulation had a higher density of nerve structures immunopositive to the SYN, GAP43, TH, and ChAT (P<.01) in both right and left atria. Nerve density was equal in right and left atria. There were more TH-positive nerve structures than ChAT-positive nerve structures (P<.01) for both right and left atria. No atrial arrhythmia was observed at the second surgery. CONCLUSIONS: Continuous subthreshold electrical stimulation to the LSG induces both sympathetic and parasympathetic hyperinnervation in both right and left atria in normal dogs. 相似文献
108.
Hepatitis B control in Europe by universal vaccination programmes: the situation in 2001 总被引:1,自引:0,他引:1
In the nine years since the Global Advisory Group of the Expanded Programme on Immunisation (WHO) set 1997 as the target for integrating hepatitis B vaccination into national immunisation programmes worldwide, 129 countries have included hepatitis B vaccine as part of their routine infant or adolescent immunisation programmes (June 2001). By the end of 2002, 41 out of the 51 countries of the WHO European Region will be implementing universal hepatitis B immunisation. The rewards of effective implementation of the programmes in countries that started 10 years ago are becoming apparent; and their success offers an exemplary model for other countries. Some other countries, however, have difficulties to incorporate hepatitis B vaccine into universal childhood immunisation programmes, because of major economic constrains and the inability to procure a constant vaccine supply. The next decade will be characterised by expanded use of hepatitis B vaccines and the increasing efforts to sustain vaccine programmes and make the vaccine available to those countries and regions that cannot afford it. In Europe, as well as in the rest of the world, work still remains to be done to support and implement interventions that will bring us closer to the WHO goal and to eradicate hepatitis B. 相似文献
109.
Peter J. Littrup M.D. Alex M. Aisen M.D. Ethan M. Braunstein M.D. William Martel M.D. 《Skeletal radiology》1985,14(3):159-163
Magnetic resonance images (MRI) of 22 patients with roentgenographically normal hips were reviewed retrospectively and the findings categorized according to age. With increasing maturity, the MR intensity of the femoral heads on spin echo images increased, as marrow fat became a dominant tissue in the head. The femoral head pattern was relatively inhomogeneous, with a broad band of diminished intensity extending in a posteromedial to anterolateral direction, corresponding to the pattern of trabecular bone. The femoral capital epiphyses were visible in younger patients as structures of bright intensity which remained evident through early adulthood. The articular cartilage of the hip joint was noted as a distinctive halo around the femoral head. An understanding of the MR pattern of the normal hip will aid in the early recognition of pathologic conditions, such as osteonecrosis. 相似文献
110.
Four chemotherapeutic agents (cyclophosphamide, 5-fluorouracil (5-FU), methotrexate (MTX), and bleomycin) were given intravenously to rats harboring the avian sarcoma virus-induced glioma. Drug content in brain, tumor, and systemic tissue was measured. The uptake of drug and the consistency of drug levels in normal brain and tumor varied widely among these agents. [14C]Cyclophosphamide and its metabolites penetrated normal brain and, to a greater extent, brain tumor. [14C]5-FU and its metabolites also entered normal brain and brain tumor, but to lesser extent than [14C] cyclophosphamide and its metabolites. Immunoreactive MTX entry into tumor was variable, ranging from 30 to 1080 ng/g of tissue, with only minimal concentrations in normal brain. After conventional doses, immunoreactive bleomycin levels in tumor were also variable, ranging from 24 to 164 mu units/g of tissue, and little if any drug entered surrounding brain. In addition, the cerebrovascular permeability of 5-FU and MTX in normal rats was measured. Utilizing the method of Rapoport, the PA (product of permeability and capillary surface area) of 5-FU was found to be 6- to 12-fold greater than that of MTX. The PA of both drugs was increased 4- to 7-fold after osmotic blood-brain barrier opening. The variable "leakiness" of glial tumors, both experimentally and clinically, as well as the varied permeabilities of different water-soluble chemotherapeutic agents, makes the drug delivery problem in brain tumors a very complex issue. 相似文献