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In rare cases the usage of the internal thoracic vessels as recipient vessels in reconstructive surgery of the head and neck region with free tissue transfer is a challenging but valid alternative if local recipient vessels are unusable.  相似文献   
3.
Application of breast cancer risk prediction models in clinical practice.   总被引:11,自引:0,他引:11  
Breast cancer risk assessment provides an estimation of disease risk that can be used to guide management for women at all levels of risk. In addition, the likelihood that breast cancer risk is due to specific genetic susceptibility (such as BRCA1 or BRCA2 mutations) can be determined. Recent developments have reinforced the clinical importance of breast cancer risk assessment. Tamoxifen chemoprevention as well as prevention studies such as the Study of Tamoxifen and Raloxifene are available to women at increased risk of developing breast cancer. In addition, specific management strategies are now defined for BRCA1 and BRCA2 mutation carriers. Risk may be assessed as the likelihood of developing breast cancer (using risk assessment models) or as the likelihood of detecting a BRCA1 or BRCA2 mutation (using prior probability models). Each of the models has advantages and disadvantages, and all need to be interpreted in context. We review available risk assessment tools and discuss their application. As illustrated by clinical examples, optimal counseling may require the use of several models, as well as clinical judgment, to provide the most accurate and useful information to women and their families.  相似文献   
4.
Background: Molecular theories of general anesthesia often are divided into two categories: (l) Anesthetics may bind specifically to proteins, such as ionic channels, and alter their function directly, and (2) anesthetics may alter the functions of integral membrane proteins indirectly through modification of the physical properties of the membrane. Recent studies have provided evidence that anesthetics can bind to proteins and modify their function directly, bringing into question the role of the membrane in anesthetic interactions. To reexamine the role of membrane lipids in anesthetic interactions, an experimental approach was used in which the membrane lipid composition could be systematically altered and the impact on anesthetic interactions with potential targets examined.

Methods: Sodium channels from human brain cortex were incorporated into planar lipid bilayers with increasing cholesterol content. The anesthetic suppression of these channels by pentobarbital was quantitatively examined by single channel measurements under voltage-clamp conditions.

Results: Changes in cholesterol content had no effect on measured channel properties in the absence of anesthetic. In the presence of pentobarbital, however, cholesterol inhibited anesthetic suppression of channel ionic currents, with 1.9% (weight/weight, corresponding to 3.5 mol%) cholesterol decreasing anesthetic suppression of sodium channels by half.  相似文献   

5.
The traditional role of the high school based community community health nurse has changed considerably over recent decades. This article describes a qualitative study, in which nine community health nurses from eight different high schools completed a diary of the interventions and events during the course of two working days in order to identify the dimensions of their role. A short demographic questionnaire was also completed by the nurses and included two open-ended questions concerning their main professional issues and concerns. The researchers sought verification of the interpretation of the data through a focus group interview with the high school nurses. Data analysis indicated that the role of the high school community health nurses (CHN) consisted of seven categories. These were provider of clinical care, counsellor/ mediator, advocacy and support, liaison/referral, health promotion/education and resource agent, and professional management and research role. The findings highlight the complex and demanding aspects of the role of the high school nurse and articulate the importance of describing the contribution of such practitioners in to the promotion of health among adolescents.  相似文献   
6.
Aseptic bone necrosis is a well known complication after corticosteroid treatment in adults and several hundred cases have been reported. Alterations in fat metabolism with vascular occlusion due to fat embolization, as well as microtraumata and osteoporosis are discussed as etiologic factors. In contrast, aseptic bone necrosis in relation to corticosteroid treatment is rare in children and adolescents. We therefore report 3 patients, aged from 10 to 18 years, suffering from severe aplastic anemia, meningeal relapse after acute lymphocytic leukemia and acute myelocytic leukemia respectively, who developed aseptic bone necrosis 6, 11, and 20 months following the onset of corticoid therapy. The patients survive from 28+ to 50+ months after diagnosis of their initial hematologic disease, as it can be expected today for increasing numbers of patients. We therefore believe, that aseptic bone necrosis may represent a serious therapy related complication and suggest that, diagnostic examination in patients with suspicious complaints of the hip, shoulder or knee should also exclude the possibility of a bone necrosis after leucemic relapse has been ruled out. Since radiological changes only develop several weeks to months after the onset of the clinical symptoms and because of the disabling consequences for patients, misdiagnosed at the beginning, a 99 technetium bone scan should be done as early as possible. Corticosteroids, despite their serious side effects are still being considered as a important part of hematologic therapy and are not being omitted in the near future, so that the earliest possible diagnosis of bone necrosis will remain of great importance.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
7.
Monoamine oxidase A gene promoter (MAOA-uVNTR) and catechol-O-methyltransferase V158M (COMT-V158M) gene functional polymorphisms are reported to be associated with impulsive-aggression, but a biological intermediate effect remains to be determined. This study assessed the association of these polymorphisms with cerebrospinal fluid (CSF) monoamine metabolites as endophenotypes. Ninety-eight Caucasian psychiatric subjects were assessed for Axis I and II diagnosis. Subjects were genotyped for the functional polymorphisms, MAOA-uVNTR and COMT-V158M. CSF was obtained by lumbar puncture. Relationships of the two polymorphism to monoamine metabolites: HVA, 5-HIAA, and MHPG were examined. The higher-expressing MAOA-uVNTR genotype was associated with higher CSF-HVA levels in males only (n = 46) (195.80 pmol/ml, SD = 61.64 vs. 161.13, SD = 50.23, respectively; P = 0.042). No association was found with diagnosis. COMT-V158M had no association with CSF monoamine metabolites. The association of MAOA-uVNTR with dopaminergic activity in males is a preliminary finding that needs to be replicated in a larger sample of Caucasian males and relationships sought with clinical phenotypes. This article contains supplementary material, which may be viewed at the American Journal of Medical Genetics website at http://www.interscience.wiley.com/jpages/0148-7299:1/suppmat/index.html.  相似文献   
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INTRODUCTION: Limited access to medical care has resulted in large numbers of patients seeking primary care for non-emergent emergency conditions in emergency departments. This influx of patients is contributing to overcrowding and delays in care for patients with emergencies. In response, a system was implemented in which persons with non-emergent medical conditions, following a medical screening examination, did not receive further ED assessment or treatment and instead were referred to community resources. The purpose of this study was to describe the characteristics of individuals who were referred to community-based services, their condition after 72 hours, and their use of follow-up health care services. METHODS: All referred cases (n=225) were reviewed for chief complaint and demographics. Phone contact was attempted after 72 hours to determine the person's condition and if community resources were utilized. RESULTS: Of the 225 cases, 52% were female, with a mean age of 33 years. Their most common chief complaints were extremity problems (16%), toothache (9%), and medication refill (8%). Follow-up phone contact was successful with 82 people (37%) an average of 14 days after their ED visit. The majority (55%) reported their condition had improved; 39%were unchanged, and 6% were worse. Thirty-one people(40%) accessed community resources and 8 (26%) returned to another emergency department. No clinically significant associations were found between patient demographics and use of community resources. DISCUSSION: Most people who were successfully contacted for follow-up and who had come to the emergency department with non-emergent chief complaints did not access community resources and their condition frequently improved. Additional studies, with improved follow-up, are needed before suggesting that referring individuals to community resources is an acceptable practice.  相似文献   
10.
This study assessed the amount of vascular endothelial growth factor (VEGF) expression and related the findings to new bone formation in the posterior glenoid fossa during stepwise mandibular advancement. A total of 250 female Sprague-Dawley rats, 35 days old, were randomly divided into 10 groups, each including 5 control and 20 experimental rats. Within each group, 10 experimental rats were fitted with functional appliances with a 1-step advancement of 3.5 mm. Another 10 were fitted with stepwise appliances with an initial advancement of 2 mm and a subsequent increase to 3.5 mm on day 30. The rats in the experimental groups were killed on days 3, 7, 14, 21, 30, 33, 37, 44, 51, and 60, respectively. The matched controls were killed on the same time points. Sections (7 microm) were cut through the glenoid fossa sagittally and stained with anti-VEGF antibody. VEGF expression in the posterior glenoid fossa was evaluated with a computer-assisted image-analyzing system. Both VEGF expression and new bone formation were greater in the experimental rats than in the controls. During stepwise advancement, initial VEGF expression was less than that of 1-step advancement, but the second advancement elicited another peak on day 44. New bone formation was also less than that of 1-step advancement during early stages of stepwise advancement but then began to increase from day 37 onward. The maximum increase was observed on day 60. Stepwise advancement of the mandible delivers mechanical stimuli that produce a series of tissue responses that lead to increased vascularization and bone formation.  相似文献   
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