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41.
Haemophilus ducreyi infection in south Florida: a rare disease on the rise?   总被引:2,自引:0,他引:2  
Increased numbers of patients with genital ulcers sought medical attention in the Palm Beach County, Florida, Sexually Transmitted Disease clinics from Aug 1, 1982 to Aug 31, 1983. We established that a small proportion of subsequent cases of genital ulcers were caused by Haemophilus ducreyi, the etiologic agent associated with chancroid. We also set up a surveillance system to monitor this sexually transmitted infection, and have illuminated several recent cases of chancroid occurring in that area. This outbreak of chancroid suggest that clinicians practicing in south Florida consider chancroid (generally a rare disease in the United States) in their differential diagnoses of genital ulcers.  相似文献   
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43.
Prolonged physical exercise is associated with multiple changes in blood hemostasis. Eccentric muscle activation induces microtrauma of skeletal muscles, inducing an inflammatory response. Since there is a link between inflammation and coagulation we speculated that downhill running strongly activates the coagulation system. Thirteen volunteers participated in the Tyrolean Speed Marathon (42,195 m downhill race, 795 m vertical distance). Venous blood was collected 3 days (T1) and 3 h (T2) before the run, within 30 min after finishing (T3) and 1 day thereafter (T4). We measured the following key parameters: creatine kinase, myoglobin, thrombin-antithrombin complex, prothrombin fragment F1 + 2, D-dimer, plasmin-alpha(2)-antiplasmin complexes, tissue-type plasminogen activator antigen, plasminogen-activator-inhibitor-1 antigen and thrombelastography with ROTEM [intrinsic pathway (InTEM) clotting time, clot formation time, maximum clot firmness, alpha angle]. Thrombin generation was evaluated by the Thrombin Dynamic Test and the Technothrombin TGA test. Creatine kinase and myoglobin were elevated at T3 and further increased at T4. Thrombin-antithrombin complex, prothrombin fragment F1 + 2, D-dimer, plasmin-alpha(2)-antiplasmin complexes, tissue-type plasminogen activator antigen and plasminogen-activator-inhibitor-1 antigen were significantly increased at T3. ROTEM analysis exhibited a shortening of InTEM clotting time and clot formation time after the marathon, and an increase in InTEM maximum clot firmness and alpha angle. Changes in TGA were indicative for thrombin generation after the marathon. We demonstrated that a downhill marathon induces an activation of coagulation, as measured by specific parameters for coagulation, ROTEM and thrombin generation assays. These changes were paralleled by an activation of fibrinolysis indicating a preserved hemostatic balance.  相似文献   
44.
In a newly developed dual-source computed tomography system (DSCT) the relation of heart rate and image quality and the possible advantages of the system’s superior temporal resolution in the evaluation of left ventricular parameters as compared to results of cardiac magnetic resonance imaging (MRI) were assessed. Coronary CT angiography was performed using a DSCT (Somatom Defintion, Siemens Medical Solutions, Forchheim, Germany) in 21 patients (mean age 62±8; 15 male, 6 female). Image quality of the coronary arteries, the heart valves, and the left ventricular myocardium was assessed using a three-point grading scale. Ten of these patients also underwent cardiac MRI for the assessment of left ventricular function, using a SSFP (steady-state free precession) sequence. Left ventricular ejection fractions (LV-EF), the end-systolic volumes (ESV), and the end-diastolic volumes (EDV) were measured employing MRI and DSCT datasets. The image quality ratings for the coronary arteries at the optimal reconstruction interval were diagnostic even in patients with high heart rates (1.42±0.49). Analysis of global LV function using DSCT quantified from CTA datasets showed a good correlation with results of cardiac MRI [EF: r=0.75 (p=0.01); ESV: r=0.72 (p=0.19); EDV: r=0.71 (p=0.02)]. The dual-source CT system offers robust image quality of the coronary arteries, independent of the heart rate, and provides combined diagnostic imaging of coronary arteries, the heart valves, the myocardium, and the global left ventricular function.  相似文献   
45.
BACKGROUND: A number of meta-analyses have led to contradictory results regarding the efficacy of the psychological and pharmacological treatment of anxiety disorders. The main reasons for these inconsistent results seem to be the inclusion of heterogeneous studies and influences of selection biases. We performed a meta-analysis, which only included studies using a direct comparison of pharmacological, psychological, or combined treatments. METHOD: Sixteen studies on panic disorder, six studies on social anxiety disorder, and two studies on generalized anxiety disorder have been analyzed. Effect sizes for differences between the different treatment modalities were calculated. Also, the effect sizes of the pre-post differences were calculated. RESULTS: Pharmacological treatment, cognitive-behavioural treatment, and the combination of both treatment modalities all led to substantial improvement between pre- and post-treatment. Combined pharmacological and psychological treatment was superior to the monotherapies for panic disorder. For social anxiety disorder, there is only preliminary support for combined treatment. Due to lack of sufficient data, no final conclusions can be drawn for generalized anxiety disorder. CONCLUSIONS: While drug treatment and CBT showed equal efficacy, only in panic disorder the combination of pharmacological and psychological treatment was superior to either treatment alone. For the other anxiety disorders, the evidence for greater efficacy of combination treatment is still not sufficient due to lack of studies.  相似文献   
46.
The Monte Carlo method was used to calculate the efficiency, escape and Compton curves of a planar high-purity germanium detector (HPGe) in the 20-150 keV energy. These curves were used for the determination of photons spectra produced by an X-ray machine in order to allow a precise characterization of photon beams applied to medical diagnosis. The detector was modeled with the MCNP5 computer code and validated by comparison with experimental data. The air kerma calculated after the spectra stripping was compared with ionization chamber measurements.  相似文献   
47.
Boerhaave’s syndrome is a life-threatening disease with a high mortality. With regard to the heterogeneity of treatment strategies, no comparative studies exist and recommendations remain controversial. Seventeen cases of Boerhaave’s syndrome operated on between 1989 and 2000 at our hospital were reviewed retrospectively to compare the time period between perforation and diagnosis, and the morbidity and mortality among the different treatment options. In addition, we conducted a meta-analysis of the literature including all series containing five or more patients and compared the findings with our own data. Our patients with a perforation history of less than 12 hours showed significantly fewer signs of sepsis compared to patients with a history of more than 12 hours. In a comparison of patients with primary repair vs. patients treated with esophageal resection or an exclusion operation, no differences were found. In the literature, patients with a long period of perforation (more than 24 hours) were treated more often with an esophageal resection than patients with primary repair. In cases of Boerhaave’s syndrome, primary suturing of the esophageal perforation should be reserved only for those patients presenting within 12 hours after perforation. In all other cases, depending on the extent of the tissue damage, a two-stage esophageal resection with cervical esophagostomy and gastrostomy is recommended as the safest treatment.  相似文献   
48.
Parallel image reconstruction using B-spline approximation (PROBER).   总被引:1,自引:0,他引:1  
A new reconstruction method for parallel MRI called PROBER is proposed. The method PROBER works in an image domain similar to methods based on Sensitivity Encoding (SENSE). However, unlike SENSE, which first estimates the spatial sensitivity maps, PROBER approximates the reconstruction coefficients directly by B-splines. Also, B-spline coefficients are estimated at once in order to minimize the reconstruction error instead of estimating the reconstruction in each pixel independently (as in SENSE). This makes the method robust to noise in reference images. No presmoothing of reference images is necessary. The number of estimated parameters is reduced, which speeds up the estimation process. PROBER was tested on simulated, phantom, and in vivo data. The results are compared with commercial implementations of the algorithms SENSE and GRAPPA (Generalized Autocalibrating Partially Parallel Acquisitions) in terms of elapsed time and reconstruction quality. The experiments showed that PROBER is faster than GRAPPA and SENSE for images wider than 150x150 pixels for comparable reconstruction quality. With more basis functions, PROBER outperforms both SENSE and GRAPPA in reconstruction quality at the cost of slightly increased computational time.  相似文献   
49.
OBJECTIVE: Although somatoform disorders are assumed to be chronic clinical conditions, epidemiological knowledge on their natural course based on representative samples is not available. METHOD: Data come from a prospective epidemiologic study of adolescents and young adults in Munich, Germany. Respondents' diagnoses (N = 2548) at baseline and follow-up on average 42 months later are considered. The follow-up incidence, stability as well as selected baseline risk factors (sociodemographics, psychopathology, trauma exposure) for the incidence and stability of somatoform disorders and syndromes are prospectively examined. Diagnostic information was assessed by using the standardized Munich-Composite International Diagnostic Interview (M-CIDI). RESULTS: Over the follow-up period, incidence rate for any of the covered somatoform diagnoses was 25.7%. Stability for the overall group of any somatoform disorder/syndrome was 48%. Female gender, lower social class, the experience of any substance use, anxiety and affective disorder as well as the experience of traumatic sexual and physical threat events predicted new onsets of somatoform conditions, while stability was predicted by being female, prior existing substance use, affective and eating disorders as well as the experience of a serious accident. CONCLUSIONS: At least for a substantial proportion of individuals, the overall picture of somatization seems to be relatively stable, but with fluctuation in the symptom picture over time. Being female, the experience of substance use as well as anxiety disorder seem to constitute risk factors for the onset of new somatoform conditions as well as for a stable course over time.  相似文献   
50.
Positron emission tomography (PET) using [(11)C]PK 11195, a ligand for peripheral benzodiazepine receptor binding sites, offers the opportunity to image activated microglia in vivo. This tool may therefore be used to display the occurrence of microglial activation in the course of neurodegeneration. A patient with the clinical diagnosis of corticobasal degeneration (CBD) and left-sided symptoms was studied using fluorodeoxyglucose (FDG) and [(11)C]PK 11195 PET. We found a marked right hemispheric hypometabolism and asymmetric microglial activation in corresponding areas of the basal ganglia and right temporal and parietal cortex. [(11)C]PK 11195 PET suggests involvement of microglial activation in the pathogenesis of CBD.  相似文献   
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