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71.
In migraine, headache severity varies with age. As a consequence, the effectiveness of medication may also depend on a patient's age. The purpose of this study was to assess the combined effect of age and drug treatment on headache characteristics. Using data from clinical trials of sumatriptan in adolescents and adults, we show how the interaction between age and drug exposure can be parameterised as a covariate on a Markov model that describes the decline of headache severity over three clinically defined stages (no relief, relief and pain-free status). The model explains important clinical observations: (i) the rates at which the pain relief and pain-free status were attained were found to be inversely related to age; (ii) in placebo-treated patients, the mean transit time from 'no relief' to 'relief' is 3 h for young adolescents and increases to 6 h for patients aged ≥ 30 years; and (iii) sumatriptan reduces the transit time to 2 h, irrespective of age. These findings indicate that the therapeutic gain over placebo increases with age. Prospective studies of antimigraine drugs should take this relationship into account when extrapolating efficacy data from adults to adolescents.  相似文献   
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Objective: The guiding criteria are considered the backbone of Chinese medicine. They have previously been described as functional features (symptoms) leading to the overall assessment of human functions on the basis of a regulatory (cybernetic) model referring to the I Ging. Methods: The Heidelberg model can explain symptoms such as created by "heat" on a rational physiological level. Results & Conclusion: The overall of physiological symptoms are shown as a schematic draft. The basis of "heat" is considered to be a general increase of microcirculation in the periphery. This leads to a couple of local pathophysiological consequences and sensations like 1) red tongue (the tongue is considered an embryological somatotopic system). 2) Sensation of warmth (by increase of capillary flow). 3) pre-inflammatory state, leading to pain modalities like "worse if pressed", as inflammations tend to be increasingly painful under pressure; 4) reddish skin, the mechanisms by which this is induced may include the release of substance P, therefore accompanied by burning sensation. Systemic pathophysiological consequences may include. Relative lack of fluid in the larger vessels, as fluid supplies peripheral capillary flow. This may lead to water saving mechanisms like thirst, dry mucosa with do, mouth, dry nose, dry lips, dry skin, and also dry stool, yellow and sparse urine.  相似文献   
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BACKGROUND: A weekly schedule of a 24-h high-dose 5-FU infusion in combinationwith folinic acid was investigated as salvage therapy in patientswith advanced gastric cancer. PATIENTS AND METHODS: Seventeen patients with progressive disease after chemotherapywere treated with a weekly schedule of 500 mg folinic acid/sqmby i.v. 2-h infusion followed by an i.v. 24-h infusion of 2.6g 5-FU/sqm times six. Fourteen of the 17 patients (82%) hadbeen pretreated in regimens which included 5-FU/folinic acidi.v. bolus. RESULTS: Toxicity was mild, with diarrhea, mucositis and nausea; WHOgrade m/IV diarrhea was observed in only two patients. Threepatients achieved partial remissions (18%; 95% confidence interval:0%–38%) and 7 patients stable disease (41%; 95% confidenceinterval: 17%–64%). Their median survival time was fivemonths (range 1.5–10 months) after the onset of salvagetherapy. CONCLUSIONS: This schedule of weekly 24-h infusions of high-dose 5-FU andfolinic acid is effective, even in patients pretreated withor resistant to regimens including 5-FU/folinic acid i.v. bolus.Based on these data, it appears that this schedule of high-dose5-FU/folinic acid in first-line combination chemotherapy meritsinvestigation. 5-fluorouracil, folinic acid, gastric cancer, salvage therapy  相似文献   
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This study examined an ecological model of maternal substance abuse and child neglect. Data are presented that identified an interplay among family history, interpersonal risk factors, current family functioning, and community networks in examinations of child neglect in a sample of substance-abusing women entering treatment.  相似文献   
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INTRODUCTION: The aim of this study was to analyse the bone regeneration on porous metallic wire-mesh specimens of pure titanium, uncoated CoCrMb and HA-coated CoCrMb in a comparative animal experiment. MATERIAL AND METHODS: Uncoated and hydroxyapatite-coated CoCrMb (one-sided) specimens were tested in an animal experiment. The statistical interpretation was done macroscopically as well as microscopically. RESULTS: With regard to the histological and quantitative evaluation, it has been shown that the proximal coated CrCoMb implants were superior to the other specimen. The bone regeneration with the most distinctive extent of osseointegration has been seen by the HA-coated CrCoMb specimen. The uncoated distal CoCrMb specimen demonstrated the worst results. DISCUSSION: This study shows that specimens of titanium and uncoated CrCoMb implanted at the proximal metaphysis deliver comparable effects on the bone regeneration and osseointegration. The best results with regard to the bone regeneration and osseointegration were seen with the implanted hydroxyadaptite-coated CrCoMb specimen. In addition, it has been observed that the bone regeneration and osseointegration of the specimen depends on the place of implantation.  相似文献   
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For biomechanical purposes, interbody fusion cages should not dislocate, should provide high stability, and should have a low subsidence risk. Zientek (Marquardt Medzintechnik), Stryker (Stryker Implants), and Ray lumbar interbody fusion cages (Surgical Dynamics) were tested in this study. They were implanted by pairs from a posterior approach without further stabilization. In a first step, each cage design was implanted into four human L3-4 segments and extracted posteriorly under an axial preload of 200 N. In a second step, standard flexibility tests were carried out with 24 human L2-3 and L4-5 specimens in an intact condition, directly after cage implantation, and after cyclic axial compression loading (200-1000 N, 40,000 cycles, 5 Hz). In a third step, a destructive axial compression test was carried out. Maximum pullout force was highest with Ray cages (median 945 N), followed by Zientek (605 N) and Stryker cages (130 N). With all three cage designs, primary stability was higher in lateral bending and flexion than in extension and axial rotation. Implantation of Ray cages caused a decreased range of motion in all three loading directions ranging between 49% and 99%. Zientek cages only stabilized in lateral bending, flexion, and extension (45-78%) and Stryker cages in none of the three loading directions. Cyclic loading caused an increased range of motion in all cases up to 190%. Axial compression force at failure was 8413 N with Ray cages, 8359 N with Stryker cages, and 5486 N with Zientek cages. The cage design seems to influence the dislocation tendency. In this regard, threaded cages or cages with anchorage systems seem to provide more security. The stabilizing effect seems to be mainly influenced by factors such as the degree of distraction or destruction of the facet joints rather than by the cage design.  相似文献   
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