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31.
Persistent sciatic artery. Report of three cases and literature review   总被引:1,自引:0,他引:1  
Persistence of the sciatic artery (SA) is a rare vascular anomaly, resulting from lack of regression of an embryonal artery to the lower extremity. Forty-nine cases have been published in the world literature since 1832. The persistent sciatic artery (PSA) is particularly prone to undergo aneurysm formation or atherosclerosis. It originates from the internal iliac artery, courses in close proximity to the sciatic nerve, and provides the main supply to the popliteal artery because a hypoplastic superficial femoral artery (SFA), contributing only collaterals to the knees, is usually associated with a PSA. This anomaly should be kept in mind in the clinical assessment of a pulsatile gluteal mass. It also presents a potential hazard during hip and renal transplant surgery.  相似文献   
32.
BACKGROUND: Worldwide, fire-related burns are a major cause of unintentional injury, morbidity and mortality, with the majority of deaths occurring in developing countries. In the US, as in other countries, most fatal fires occur in the home. Effective prevention strategies for residential fires are, however, currently underutilized. The news media is one available communication channel to promote such strategies, and analyzing current news coverage is a first step towards incorporating media advocacy into injury prevention efforts related to residential fires. METHODS: Four daily newspapers circulating widely in Maryland were monitored for 1 year. Articles describing residential fires were coded for measures of prominence, content and frame. Analysis focused on measures of issue newsworthiness, reporting of causation and consequences of fires, and inclusion of public health context and conveyance of prevention messages. RESULTS: The data indicate that fires are newsworthy, with 374 relevant news articles in a 1-year period, 32% of which appear on the first page of a section. Coverage generally concerned recent local fire events. Most articles discussed the consequences of fires (88%), and identified a causal factor (58%). Only 36%, however, included prevention information, and less than one-quarter set residential fires in a public health context. CONCLUSION: The newsworthiness of residential fires provides a clear opportunity for widespread communication around injury prevention. Improving media advocacy will entail framing discussion of recent fire events in such a way as to support inclusion of prevention strategies and a public health context in news coverage.  相似文献   
33.
Activated nuclear factor-kappaB (NF-kappaB) and inducible nitric oxide synthase (iNOS) were detected immunohistochemically in pleuropneumonic lungs from 20 pigs naturally infected with Actinobacillus pleuropneumoniae. NF-kappaB was detected mainly in nuclei of inflammatory cells, confirming its activation. Intense immunolabelling for NF-kappaB and iNOS was seen within the lung lesions, but labelling was minimal in unaffected portions of the lung of infected pigs and in normal lung from uninfected (control) pigs. Examination of serial sections from the 20 infected lung samples demonstrated a close association between NF-kappaB and iNOS. This suggests that NF-kappaB plays a key role in triggering the activation of iNOS in porcine pleuropneumonia.  相似文献   
34.
It was our purpose to determine the characteristics of practitioners in the United States who were among the first to inquire about and use the BRCA1 and BRCA2 (BRCA1/2) genetic tests outside of a research protocol. Questionnaires were mailed to all practitioners who requested information on or ordered a BRCA1/2 test from the University of Pennsylvania (UPenn) Genetic Diagnostics Laboratory (GDL) between October 1, 1995 and January 1, 1997 (the first 15 months the test was available for clinical use). The response rate was 67% of practitioners; 54% (121/225) were genetic counselors, 39% (87/225) were physicians or lab directors. Most physicians were oncologists, pathologists, or obstetrician/gynecologists, but 20% practiced surgery or internal or general medicine. Fifty-six percent (125/225) had ordered a BRCA1/2 test for a patient; most of the rest had offered or were willing to offer testing. Of those who had offered testing, 70% had a patient decline BRCA1/2 testing when offered. Practitioners perceived that patients' fear of loss of confidentiality was a major reason for declining. Nearly 60% of practitioners reported that their patients had access to a genetic counselor, but 28% of physicians who ordered a BRCA1/2 test reported having no such access, despite the GDL's counseling requirement. The proportion of physicians reporting no access to genetic counselors for their patients increased from 22.4% in the first half of the study to 50% in the last half. Many practitioners have an interest in BRCA1/2 testing, despite policy statements that discourage its use outside of research protocols. Practitioner responses suggest that patient interest in testing seems to be tempered by knowledge of potential risks. An apparent increase in patient concern about confidentiality and inability to pay for testing could indicate growing barriers to testing. Although most practitioners reported having access to counseling facilities, perceived lack of such access among an increasing proportion of practitioners indicates that lab requirements for counseling are difficult to enforce and suggests that an increasing proportion of patients may not be getting access to counseling.  相似文献   
35.
Autoimmune cholangitis is a clinical constellation of chronic cholestasis, histological changes of chronic nonsuppurative cholangitis and the presence of autoantibodies other than antimitochondrial antibody (AMA). It is uncertain whether this entity is definitely different from AMA positive primary biliary cirrhosis (PBC), though it shows some differences. We report a case of autoimmune cholangitis in a 59-year-old woman, who had been previously diagnosed as AMA-positive PBC associated with rheumatoid arthritis, has been converted to an AMA-negative and anticentromere antibody-positive PBC during follow-up. The response to ursodeoxycholic acid treatment is poor except within the first few months, but prednisolone was dropping the biochemical laboratory data.  相似文献   
36.
The HLA-B51 allele is known to be associated with Behcet's disease (BD) in many ethnic group. However, it has not yet been clarified whether the HLA-B51 gene itself is the pathogenic gene related to BD or whether it is some other gene in linkage disequlibrium with HLA-B51. Recently, the Triplet repeat (GCT/AGC) polymorphism in transmembrane region of the MHC class I chain-related A (MICA) gene was identified. To investigate the association of MICA with BD, we studied the MICA polymorphism in 108 Korean BD patients and 204 healthy controls in relation to the presence of HLA-B51 and clinical manifestations. The triplet repeat polymorphism was determined by polymerase chain reaction (PCR)-denaturing polyacrylamide gel electrophoresis (PAGE). The phenotype frequency of the MICA*A6 allele (relative risk, RR=2.15, p=0.002) and HLA-B51(RR=1.87, p=0.022) were significantly increased in the Korean patients with BD. A strong linkage disequilibrium was observed between the MICA*A6 and HLA-B51 in both the patients with BD and control subjects. Stratification analysis showed that MICA*A6 homozygosity was strongly associated with BD in the HLA-B51-negative population, and HLA-B51 was also associated with MICA*A6-negative population. In conclusion, MICA*A6 rather than HLA-B51 was strongly associated with Korean patients with BD, and the MICA*A6 allele is a useful susceptibility marker of BD, especially in the HLA-B5-negative  相似文献   
37.
Chung Y  Cho J  Chang YS  Cho SH  Kang CY 《Immunobiology》2002,206(4):408-423
Allergic asthma is an inflammatory disease of the airways, and Th2 cells secreting IL-4 and IL-5 play a pivotal role in its pathogenesis. We have previously demonstrated that oral tolerance can be induced and maintained more profoundly in a Th2-related immune response, and that an ongoing immune response can be suppressed by the oral administration of antigen combined with an appropriate feeding regimen. In the present study, we examined the preventive and therapeutic effects of the oral administration of allergen on a Th2-mediated immune disorder using a murine model of asthma. Our results show that the development of asthma can be blocked completely by orally administering allergen. Airway hyperreactivity, allergen-specific IgE production, Th2-derived cytokines, allergen-induced T cell proliferation and the infiltration of inflammatory effector cells into the lung were prevented by such oral administration. To assess the therapeutic effects of oral administration on the progression of asthma, we tested the effects of oral tolerance in an established asthma model, and found that a multiple high dose-feeding regimen was effective at suppressing the progression of mild asthma. In the high dose-feeding group, the number of eosinophils in bronchoalveolar lavage fluid was reduced and airway reactivity also decreased. However, this was insufficient to reduce airway reactivity and eosinophilia in bronchoalveolar lavage fluid in cases of severe asthma. These results demonstrate that allergic asthma may be ameliorated by feeding allergen; there is hope that these results will provide a new immunotherapeutic strategy for allergic asthma.  相似文献   
38.
Brain tumors in infants present special diagnostic and therapeutic challenges. To figure out the clinical features, pathological classification of the tumors and the treatment outcome of infantile brain tumors, 458 children (age<16) with brain tumors were reviewed retrospectively. Among them 21 cases (4.6%) were diagnosed during the first 12 months of life. Two tumors were definitely of congenital origin. The majority of infants with brain tumors presented with increased intracranial pressure. Fourteen tumors were located at the supratentorial area. Sixteen cases had neuroepithelial tumors; astrocytoma (optic pathway), supratentorial primitive neuroectodermal tumor (PNET) and medulloblastoma were found in three cases each. There were two treatment-related mortalities. Compared with the outcomes in older children, the treatment outcome was poorer in medulloblastoma and the optic pathway glioma which showed a higher growth potential. Because of the limited application of postoperative adjuvant therapy, radical surgical removal played a more important role in this age group. The prognosis of patients in whom the tumors could not be totally removed, largely depended on the pathological malignancy of the tumors. Though the treatment outcome was not always dismal, immaturity of the brain, higher growth potential, perioperative risks, limitations in adjuvant therapy, and pessimistic attitude on the part of parents made management more challenging.  相似文献   
39.
The hypertensive-diabetic rat is a new small animal model of cardiomyopathy characterized by ventricular damage. To determine the extent of pathology in this model, quantitation of light microscopic changes in hearts from 15 hypertensive-diabetic rats and 15 age-matched controls was performed. The fraction of myocardium involved by interstitial fibrosis, myocyte necrosis, replacement fibrosis, vascular sclerosis and perivascular fibrosis was computed separately for right and left ventricles. Spontaneously dying as well as deliberately killed hypertensive-diabetic rats were studied. Spontaneously dying animals had higher systolic blood pressures compared with rats killed deliberately. Body weights were lower and lung weights higher in the former group. Left and right ventricular necrosis and fibrosis were increased in spontaneously dying compared with deliberately killed rats. The degree of right ventricular necrosis and fibrosis paralleled that in the left ventricle, but was, unexpectedly, several times greater in magnitude. Thus, quantitative histology in the hypertensive-diabetic rat reveals more cardiac necrosis and fibrosis, in either ventricle, from spontaneously dying animals compared with deliberately killed rats. This damage, coupled with major functional alterations in the viable myocardium, may lead to congestive heart failure or arrhythmia.  相似文献   
40.
BACKGROUND AND PURPOSE: The optimal intensity fluence profile of a beam depends on the profiles of other beams but most optimizations assume fixed beam orientations, a priori. Breast cancer radiotherapy attempts to cover the target and to spare critical structures such as the heart and lungs. The study aims are (1) to determine and document the optimal two-beam orientation that best spares the heart for left-sided breast cancer patients and (2) to investigate the influence of the treatment technique (i.e., conformal versus intensity modulation) on the optimal objective cost function. MATERIAL AND METHODS: Ten left-sided breast cancer patients were planned using a conformal (3DCRT) and a simplified intensity modulated (sIMRT) technique using predefined segments and different two-beam orientations. Optimal segment weights were determined exhaustively for all axial two-beam combinations, in 5 degree increments, by minimizing a quadratic objective cost function. The resulting objective cost function was analyzed with respect to target geometry and treatment technique. RESULTS: The sIMRT plans are generally less sensitive to beam orientation compared to 3DCRT plans. Optimal two-beam orientations for 3DCRT and sIMRT plans exist and they correspond to a hinge angle of approximately 188 degrees and 160 degrees or 210 degrees (the latter is bimodal), respectively. CONCLUSIONS: The optimization software is a useful tool that can test many different beam combinations and estimate their associated objective cost values. Afterwards, the most promising beam orientations could be re-optimized under the TPS to fine-tune and verify the dose distributions. Optimal uniform two-beam orientations for the breast consist of opposing tangential medial and lateral beams. Optimal nonuniform two-beam orientations for left-sided breast cancers are bimodal, containing hinge angles around 160 degrees and 210 degrees. Nonuniform beam techniques are less sensitive to beam orientation compared to uniform beam techniques and result in significantly improved heart sparing but at a cost of slightly compromised planning target volume coverage.  相似文献   
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