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61.
Clinical research on the deposition of inhaled substances (e.g. inhaled medications, airborne contaminants, fumes) in the lungs necessitates anatomical models of the airways. Current conducting airway models lack three‐dimensional (3D) reality as little information is available in the literature on the distribution of the airways in space. This is a limitation to the assessment or predictions of the particle deposition in relation to the subject’s anatomy. Detailed information on the full topology and morphology of the airways is thus required to model the airway tree realistically. This paper presents the length, diameter, gravity, coronal and sagittal angles that together describe completely the airways in 3D space. The angle at which the airways branch out from their parent (branching angle) and the rotation angle between successive bifurcation planes are also included. These data are from the study of two sets of airways computed tomography (CT) images. One CT scan was performed on a human tracheobronchial tree cast and the other on a healthy male volunteer. The airways in the first nine generations of the cast and in the first six conducting generations of the volunteer were measured using a computer‐based algorithm. The data contribute to the knowledge of the lung anatomy. In particular, the spatial structure of the airways is shown to be strongly defined by the central airways with clear angular lobar patterns. Such patterns tend to disappear with a mean gravity, coronal and sagittal angles of 90° in each generation higher than 13–15. The mean branching angle per generation appears independent of the lobe to which the airways belong. Non‐planar geometry at bifurcation is observed with the mean (± SD) bifurcation plane rotation angle of 79 ± 41° (n = 229). This angle appears constant over the generations studied. The data are useful for improving the 3D realism of the conducting airway structure modelling as well as for studying aerosol deposition, flow and biological significance of non‐planar airway trees using analytical and computational flow dynamics modelling.  相似文献   
62.
Stefan Evers  MD    Ingo-Wilhelm Husstedt  MD 《Headache》1996,36(7):429-432
Indomethacin is the drug of first choice in chronic paroxysmal hemicrania with clear relief of pain as a diagnostic criterion. In a few cases, indomethacin is not tolerated because of side effects. Therefore, the efficacy of carbamazepine, verapamil. sumatriptan. acetylsalicylic acid, and oxygen as drugs in the prophylactic or acute treatment of chronic paroxysmal hemicrania was studied in a prospective open trial with 10 patients suffering from chronic paroxysmal hemicrania. The trial results, in accordance with a review of the literature. suggest that acetylsalicylic acid (and probably naproxen and diclofenac) and verapamil are the most effective drugs of second choice in chronic paroxysmal hemicrania. The efficacy of sumatriptan in this condition needs still to be clarified. although there is evidence for partial efficacy. Carbamazepine and oxygen did not show any significant influence on chronic paroxysmal hemicrania.  相似文献   
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SUMMARY The use of antimicrobial agents for the treatment of acute diarrhoea has become more common with the introduction of quinolone compounds, which are active against most types of bacterial pathogens. Despite the fact that such drugs have been used for empirical therapy or even for prophylaxis, current opinion would restrict their use to specific groups of patients who are likely to show particular benefit from them. Non-specific therapy seems a more appropriate initial treatment for cases of acute, non-dysenteric diarrhoea. Clinical trial data are presented here comparing the effects of loperamide oxide 1 and 2 mg to those of placebo and loperamide 2 mg in this condition. All the drug preparations were significantly superior to placebo, in particular reducing the time to complete relief of symptoms to about 24 hours, as opposed to 45 hours on placebo treatment. Of these preparations, loperamide oxide 1 mg is to be preferred, as it produces fewer constipation-like episodes after treatment. The introduction of loperamide oxide 1 mg represents a useful advance in the non-specific treatment of acute, non-dysenteric diarrhoea.  相似文献   
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Oral Diseases (2010) 16 , 774–780 Summary: Overexpression of ErbB receptors is frequent in head and neck squamous cell carcinomas (HNSCC) and seems to be correlated with tumor progression and metastasis. Fatty acid synthase (FASN), the key lipogenic enzyme responsible for the endogenous synthesis of fatty acids, is regulated by ErbB2 and overexpressed in several human malignancies. Methods: This study was performed to examine the immunohistochemical expression patterns of ErbB1, ErbB2, ErbB3, ErbB4, and FASN in a tissue microarray, containing 33 representative areas from aggressive primary HNSCC (whose patients had distant metastasis), and 21 matched lung metastasis. Results: Strong correlation among the expression of ErbB family receptors was found (ErbB1–ErbB2 P = 0.008, ErbB1‐ErbB4 P = 0.018, EbB2‐ErbB3 P = 0.001, ErbB2‐ErbB4 P = 0.006, ErbB3‐ErbB4 P = 0.012) in the HNSCC. FASN expression was significantly associated with ErbB2 (P = 0.024). Lymphatic permeation was correlated with ErbB3 (P = 0.033) and histological grade with ErbB4 staining (P = 0.050). ErbB1 and ErbB2 were found mainly in patients with smoking habit (P = 0.011 and P = 0.027), and ErbB2 was associated with alcohol consumption and clinical stage (P = 0.014 and P = 0.031). Finally, FASN was overexpressed in lung metastasis, in comparison with matched HNSCC samples (P = 0.006). Conclusions: The results showed that high FASN immunohistochemical expression is a feature of HNSCC lung metastasis, and ErbB1‐ErbB2, ErbB1‐ErbB4, ErbB2‐ErbB3, ErbB2‐ErbB4, and ErbB3‐ErbB4 expression levels are correlated in the respective primary tumors, being ErbB2 the preferred coexpression partner of all the other ErbB receptors.  相似文献   
68.
Migraine patients show a specific cognitive processing with a loss of habituation in the interval and a normal habituation in the attack as measured by event-related potentials (ERPs). It is unknown whether the loss of habituation changes during the migraine interval or is a stable state. Serotonin (5HT) metabolism is involved in the pathophysiology of migraine and also in the generation of ERPs. We enrolled 14 patients with regular migraine attacks in order to measure visually evoked ERPs repetitively during the migraine interval and in the migraine attack. Cognitive habituation was evaluated by analysis of P3 latency. Platelet serotonin content and free serotonin plasma level were measured at the same time points. The loss of habituation increased continuously during the migraine interval and abruptly normalized in the migraine attack (p < 0.05, time series analysis). The platelet 5HT content decreased significantly in the migraine attack (p < 0.03) and was at its maximum in the middle of the interval. The P3 latency was significantly increased in the attack (p < 0.01) and was significantly inversely correlated with the platelet 5HT content (r = -0.44, p < 0.001). Free 5HT plasma levels did not show any significant change. Our findings suggest that loss of cognitive habituation continuously increases during the migraine interval until its normalization in the migraine attack. This phenomenon cannot be attributed to serotonergic transmission. In patients with regular changes of cognitive habituation before the migraine attack, it might be possible to predict the attack by analysing ERPs.  相似文献   
69.
Although studies with interleukin-1 receptor antagonist (IL-1ra) in animal models have shown that IL-1 contributes to mortality in sepsis, the mechanisms whereby IL-1 mediates lethal effects are not well established. A possible mechanism is that IL-1 enhances the activation and release of other inflammatory mediator systems such as coagulation, fibrinolysis, neutrophils, and secretory-type phospholipase A2 (sPLA2). We investigated this possibility by assessing the effect of intravenously injected recombinant human IL-1 alpha (rhIL-1 alpha) on these plasma parameters in baboons. In addition, we examined the course of these inflammatory parameters in baboons after a challenge with a lethal dose of Escherichia coli and while receiving a 24-hour constant infusion of IL-1ra or placebo. Intravenous administration of IL-1 alpha (10 micrograms/kg) induced the formation of thrombin, as evidenced by the appearance of thrombin-antithrombin III (TAT) complexes into the circulation (peak levels, 188 +/- 92 ng/mL at 2 hours), as well as the activation of fibrinolysis, assessed by circulating plasmin-alpha 2- antiplasmin complexes (PAP complexes; peak levels, 0.4% +/- 0.03% of fully activated plasma at 1 hour), the release of tissue-type plasminogen activator (t-PA; peak levels, 6 +/- 2 ng/mL at 2 hours), and its inhibitor, plasminogen activator inhibitor (PAI; peak levels, 724 +/- 246 ng/mL at 4 hours). Il-1 alpha administration also induced the release of sPLA2 (maximal levels, 336 +/- 185 ng/mL at 8 hours), but not degranulation of neutrophils. In the septic baboons, a significant reduction of the formation of thrombin (peak TAT levels decreased from 582 +/- 78 ng/mL to 219 +/- 106 ng/mL; P < .005), the release of t-PA (peak levels decreased from 37 +/- 11 ng/mL to 17 +/- 2 ng/mL; P < .001), and its inhibitor, PAI (peak levels decreased from 2,639 +/- 974 ng/mL to 1,110 +/- 153 ng/mL; P <.001), was observed in the group receiving IL-1ra compared to that receiving placebo. The release of neutrophilic elastase was also significantly attenuated in IL-1a-treated animals (peak levels, 1,024 +/- 393 and 655 +/- 104 ng/mL in control and treatment groups, respectively; P < .05). The difference between sPLA2 levels in both groups, although higher in the controls (maximal levels, 3,140 +/- 1,435 ng/mL in control v 2,217 +/- 1,375 ng/mL in IL-1ra-treated group), was not significant. Thus, IL-1 contributes to activation of various other mediator systems in severe sepsis in nonhuman primates. We propose that these effects may explain the lethal actions of IL-1 in this sepsis model and suggest a similar role for IL-1 in severe human sepsis.  相似文献   
70.
Evers S  Wibbeke B  Reichelt D  Suhr B  Brilla R  Husstedt I 《Pain》2000,85(1-2):191-200
Headache is one of the most important factors influencing the quality of life in patients infected with the human immunodeficiency virus type 1 (HIV). However, only symptomatic headache but not changes or primary headache types during HIV infection have been studied to date. Therefore, we aimed to determine the impact of an HIV infection on frequency and semiology of different primary headache types. Patients with confirmed HIV type 1 infection underwent a neurological examination, neuroimaging or EEG, and a standardized interview. Time pattern and symptoms of headaches (cross-sectional analysis), changes of headaches preexisting to their infection (longitudinal retrospective analysis), and changes of primary headaches during a 2-year follow-up (longitudinal prospective analysis) were evaluated as were the correlations between these headache patterns and different markers of HIV infection. One hundred thirty-one consecutive HIV-infected patients without evidence of a cerebral manifestation except mild encephalopathy were enrolled. The point prevalence of migraine was 16.0% (confidence interval (CI) 10.1-25.4%), of headache with a semiology of tension-type headache 45.8% (CI 33.7-62.2%), and of other headache types 6.1% (CI 3.0-12.5%). During the natural course of infection, the migraine frequency significantly decreased in the retrospective and in the prospective analyses, whereas the frequency of the headache with a semiology of tension-type headache significantly increased in all three analyses. In 20% of all patients, the tension-type headache could be considered as symptomatic due to the infection but not due to focal or general cerebral lesions. Changes of primary headache were significantly associated with different stages of the infection and with the presence of mild encephalopathy but not with antiretroviral treatment or CD4 cell count. HIV infection seems to be associated with a progressive decrease in migraine frequency and intensity which probably is related to the immunological state of the patients. Tension-type headache becomes more frequent during HIV infection. However, this can in part be related to secondary headache caused by the HIV in less than 50% of patients with tension-type headache. The progressing immunological deficiency of HIV-infected patients seems to influence pain processing of primary headache types in different ways.  相似文献   
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