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41.
According to the hypothesis of Jannetta, an arterial compression of the left root entry zone (REZ) of cranial nerves IX and X by looping arteries could play an important role in the pathogenesis of essential hypertension. In an initial anatomical study, the positions of the left vagus and glossopharyngeal nerves in the skull were radiographically determined in 10 cadavers. By using a pattern of REZ topography developed from this information, the angiographic findings in 107 hypertensive and 100 normotensive patients were then compared retrospectively. In 80% of the angiograms of the hypertensive patients that could be evaluated, an artery crossed the left REZ of cranial nerves IX and X. Most frequently, this was the posterior inferior cerebellar artery (35.3% of cases), followed by the vertebral artery (29.4% of cases) and the anterior inferior artery (19.1% of cases). In 9 cases (13%), both the posterior inferior cerebellar artery and the vertebral artery appeared in the REZ. Frequently, a larger diameter of the left vertebral artery was found. The angiograms of normotensive patients that could be evaluated revealed an artery in the REZ in only 34.5% of cases. Our results support the hypothesis that essential hypertension may be associated with neurovascular compression of the left REZ of cranial nerves IX and X.  相似文献   
42.
Recent research suggests that, for some people with severe mental illness, supported employment could improve vocational outcomes for little additional expense. This study describes the costs and client outcomes in one mental health center that converted two rehabilitative day treatment programs to supported employment. Converting from day treatment to supported employment improved vocational outcomes significantly without increasing costs. Although total costs for community treatment were lower in both sites after implementing supported employment, differences appeared to be due to decreasing unit costs over the study period. Results illustrate the importance of testing the effects of cost estimation methods on findings.This study was supported by West Central Services, the New Hampshire Division of Mental Health and Developmental Services, and NIMH grant K02-MH-00839. The authors are grateful to Jesse Turner and Phil Wyzik for facilitating the research.  相似文献   
43.
Objectives: To determine the incidence of alcohol use in subcritically injured patients presenting to the ED, by using a saliva alcohol test (SAT) at ED triage during the ED initial assessment; to compare the incidence of alcohol use revealed by the SAT with documentation of alcohol use by ED nurses and emergency physicians (EPs) blinded to the SAT results; and to describe the demographics of the SAT-positive, subcritically injured population.
Methods: A blinded, prospective, observational evaluation of ED patients presenting with subcritical injuries was performed. The patients were tested for alcohol use with an SAT, and a subsequent record review was conducted for extraction of demographic data and evidence of documentation of alcohol use by ED nurses and EPs blinded to the SAT results.
Results: During the study. 791 subcritically injured patients had SATs performed. Twenty-one percent of these patients were found to be alcohol-positive by SAT. Either the ED nurse or the EP documented a clinical impression of alcohol use for 52% of the SAT-positive patients. There were higher SAT-positive rates among men (24%), victims of assault (47%), and patients arriving at night (41%).
Conclusions: While the SAT identified 21% of the subcritically injured patient population as alcohol-positive, ED nurse and EP documentation did not identify half of these alcohol-positive patients. Many of these patients may be at risk for additional injuries related to their drinking behavior.  相似文献   
44.
45.
The statistical significance of ophthalmological and pediatric findings in the development of retinopathy of prematurity (ROP) was evaluated in a retrospective study of 338 premature infants. Short gestation time, frequent hypoxia, and low birthweight were strongly correlated with advanced stages of ROP. The influence of Vitamin E treatment, duration of oxygen therapy, and need for transfusions was less significant. Neither multiple births nor the infant's sex had any influence on the development of ROP. Cryotherapy appears to reduce ROP, but the number of cases in the present study was too small to permit statistical analysis.  相似文献   
46.
47.
The effect of in vitro infection with herpes simplex virus 1 (HSV-1) on the Interleukin-1 (IL-1) activity of murine keratinocytes was investigated. IL-1 alpha mRNA synthesis was measured by the Northern blot technique, and the IL-1 protein production was measured in terms of the ability of dialysed supernatants from cultures of uninfected and HSV-1 infected keratinocytes to enhance mitogen-induced murine thymocyte proliferation. IL-1 alpha mRNA-synthesis in uninfected keratinocytes was detected 24 h and 48 h after isolation of the keratinocytes. IL-1 protein secretion by these keratinocytes was measureable at 18 h and reached a peak of 73 h, whereas intracellular and membrane-bound IL-1 protein production reached a maximum after 25 h. Keratinocytes, which had been cultured in vitro for 18 h, were infected with HSV-1 for 2 h and further cultured for an additional 4 h or 22 h before IL-1 measurements. A marked reduction of IL-1 alpha gene-expression was noted 6 hours after HSV-1-infection of keratinocytes, and nearly total shut-off was detected after infection for 24 h. Reduced gene-expression was paralleled by a reduction in the IL-1 protein secretion from the HSV-1 infected keratinocytes.  相似文献   
48.
Blepharoplasty and inferior punctal occlusion were performed on 24 consecutive patients with dry eye syndrome. Fifteen patients (62.5%) had symptomatic dry eye syndrome preoperatively and nine patients (37.5%) had asymptomatic dry eye syndrome diagnosed during the preoperative workup (subclinical dry eye syndrome). After surgery, nine patients (37.5%) had improvement of their dry eye syndrome, 10 patients (42%) were unchanged, and two patients (8%) had worsening of their dry eye syndrome. A third patient had worsening of the dry eye syndrome 6 months postoperatively when her puncta reopened. Two patients (8%) had increased irritation only when wearing contact lenses, but in one patient this resolved 6 months after surgery. Thus, although a significant number are improved, a few patients will have worsening of dry eye syndrome after blepharoplasty and inferior punctal occlusion.  相似文献   
49.
Computer assisted operation planning systems are gaining increasing recognition in the field of surgery. These systems offer new possibilities for preparing an intervention, with the goal of reducing the amount of expensive operating-room time required for the intervention. The safest and most effective surgical approach should always be selected, but it is often difficult to transfer the output of the planning system to the intra-operative situation so that the planning results can be considered during the actual intervention. At the Fraunhofer Institute for Computer Graphics (IGD) in Darmstadt and the Centre for Advanced Media Technology (CAMTech) in Singapore methods are being developed to bridge the gap between the external planning session and the intra-operative case: Augmented Reality (AR) techniques are used to overlay preoperative scanned image data, as well as results of the planning session, on the operation field.  相似文献   
50.
Ovalbumin (OVA) is a major allergen (Gal d II) of hen egg white and is often the cause of hypersensitivity reactions to food. Further knowledge of the antigenic and allergenic epitopes of allergens will provide better treatment of this disease. To analyse these epitopes we produced a panel of monoclonal antibodies (mAbs) against native OVA. The initial information about the epitopes was obtained with the binding patterns of these mAbs in IEF-immunoprints and western blots of OVA under reducing and non-reducing conditions. It was possible to demonstrate that the different conformations of OVA exhibit different epitopes, and that there are other epitopes which are shared by each conformation. Seven different, although sometimes overlapping epitopes, could be determined on native OVA; four different epitopes on denaturated non-reduced OVA by means of immunoblots of the intact molecule. The number of epitopes which could be differentiated by the mAbs was increased by the use of peptide blots after CNBr fragmentation of the molecule. IgE binding to different OVA conformations and to CNBr-fragments of OVA was also detectable and appears in the same regions as the reactivity of some mAbs. Western blots of OVA and CNBr-peptides demonstrate that some antigenic/allergenic binding sites seem at least partly to be continuous epitopes. The identification of the CNBr-fragments was performed by a microsequence analysis of blotted CNBr-fragments after a 2-dimensional electrophoresis. IgE was found to bind the two largest CNBr-fragments (residues 41-172 and 301-385), but not the fragment corresponding to residues 173-196. A number of monoclonal antibodies also reacted with the two large fragments, especially with fragment 301-385, and some bind also to shorter peptides, such as fragment 173-196, which were not reactive to patients' IgE. Most of the monoclonal antibodies and patients' IgE bind to the fragments 41-172 and 301-385 in 2D-PAGE blots suggesting that these fragments are involved in an immunogenic structure.  相似文献   
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