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排序方式: 共有891条查询结果,搜索用时 15 毫秒
1.
S Hammes† S Roos† C Raulin†‡ H-M Ockenfels§ B Greve† 《Journal of the European Academy of Dermatology and Venereology》2007,21(9):1229-1233
BACKGROUND AND OBJECTIVE: The use of cold air cooling (CAC) and cryogen spray cooling during dye laser treatment of port-wine stains (PWS) has become a standard in recent years. Still unsolved is the question of which fluences are necessary in combination with CAC in order to achieve an optimum clearance and the lowest possible rate of side-effects. STUDY DESIGN: In a prospective study, we treated 11 patients with PWS with pulsed dye laser (Photogenica V, Cynosure, lambda = 585 nm, iota(p) = 0.5 ms, spot size = 7 mm). Each PWS was partitioned into three areas: (area 1) 6 J/cm(2) without CAC, (area 2) 6 J/cm(2) with CAC (level 4), (area 3) 9 J/cm(2) with CAC (level 4). RESULTS: Area 3 (mean, 59%) showed a slightly better clearance than area 1 (mean, 57%); in area 2, we observed a reduced clearance (mean, 45%). Compared with area 1, we achieved a reduction of pain through CAC in areas 2 and 3. The healing periods as well as the rate of side-effects were comparable in all areas. CONCLUSION: We observed a slight but not statistically relevant increase in clearance with the use of higher fluences and CAC compared with lower fluences without CAC. Because pain is lowered significantly when using CAC, and because this makes the treatment more comfortable for the patients, we tend to recommend the use of higher fluences (9 J/cm(2)) with simultaneous CAC for treating PWS. 相似文献
2.
F Sène Diouf A M Basse A K Ndao M Ndiaye K Touré A Thiam M M Ndiaye A G Diop I P Ndiaye 《Annales de Réadaptation et de Médecine Physique》2006,49(3):100-104
OBJECTIVE: To evaluate the functional outcome in patients followed in the department of neurology of Dakar for stroke. MATERIALS AND METHOD: Prospective longitudinal observational study from August 2003 to May 2005 included inpatients or outpatients with stroke one month or less from entry confirmed by computed tomography scan. Patients were followed monthly for 12 months. At each visit, data on functional autonomy measured by the Barthel index and the treatments received were collected. RESULTS: One hundred and seventy patients aged 25 to 90 years (mean 61+/-13 years) were evaluated. The sex ratio was 0.68. A total of 64.7% of strokes involved ischemic cerebral vascular accidents and 35.3% hemorrhagic vascular accidents. Right hemiplegia was present in 55.9%, left hemiplegia in 42.9% and bilateral paresis in 1.2% of patients. A total of 28.8% of patients died between d0 and d30, 50.6% within one year. At entry, the Barthel score was greater than 60 in only 4.7% of patients. After one-year follow-up, 58.3% of the patients had a Barthel score greater than 60, 19.1% had a score between 20 and 40 and 22.6% a score between 40 and 60. Only 53.5% received rehabilitation care. The parameters significantly associated with a functional recovery were age less than 55 years (P<0.05), hemorrhagic vascular accident as opposed to ischemic vascular accident (P<0.05), and earlier rehabilitation care under qualified personnel (P<0.01). DISCUSSION: Our study shows an important rate of mortality during the first year following stroke and the rather young age of our population. The parameters associated with a better functional recovery are comparable to most of the data in the literature. The results of our study suggest that it is possible to improve functional prognosis after stroke by setting measures of prevention of the risk factors and rehabilitation in the early management of hemiplegia. 相似文献
3.
Increasing the utilization of cost-effective health services through changes in demand 总被引:1,自引:0,他引:1
Attaining efficiency in a health care system with a budget constraint involves increasing the utilization of the most cost-effective services. This can be achieved by adjustments to prices, cost curves, or demand curves. In this paper, the potential for demand curve adjustments is examined by selecting two apparently cost-effective services (prenatal care and childhood immunization against tuberculosis), and analyzing the factors explaining their utilization. Data from recent household surveys in Burkina Faso and Niger are used. A multivariate analysis of utilization employs income, price, and taste variables. Utilization is highly sensitive to the distance which must be travelled to the health facility, a price, and taste variables. Utilization is highly sensitive to the distance which must be travelled to the health facility, a price variable. Members of certain ethnic groups tend to use the services less, other things being equal. The importance of demand-side factors like ethnicity points to certain kinds of policy interventions like information, education and communication activities which could increase the utilization of cost-effective services. 相似文献
4.
We report three cases of pernicious anemia diagnosed in women in Africa. All three women had macrocytic anemia with megaloblasts evident on medullogram. The patients had neurological signs of combined sclerosis and the presence of megaloblasts confirmed the diagnosis of pernicious anemia. All were successfully treated parenterally with vitamins. This disease seems to be underdiagnosed in Africa given the number of cases reported in previous studies. 相似文献
5.
We investigated the systemic immunotoxic potential of respiratory exposure to diesel exhaust particles (DEP) in this study. Female B6C3F1 mice (approximately 8 weeks old) were exposed to increasing concentrations of DEP intratracheally, 3 times every two weeks, and sacrificed 2 or 4 weeks after the first exposure. The systemic toxicity and immune status in mice were evaluated. Mice exposed to DEP (1 to 15 mg/kg) showed no significant changes in body, spleen, or liver weights. Lung weights were increased in the mice exposed to 15 mg/kg DEP for 2 or 4 weeks. Except for a decreased platelet count, no significant alterations occurred in hematological parameters following DEP exposure. The number of splenic anti-sheep red blood cell (sRBC) IgM antibody-forming cells (AFC) decreased following DEP exposure for 2 weeks. This effect was less severe following 4 weeks of exposure and was only evident in the high dose group. Exposure to DEP also resulted in a significant decrease in the absolute numbers and the percentages of total spleen cells for total, CD4(+), and CD8(+) T cells, while the numbers of B cells and total nucleated cells in spleen were not significantly changed. The proliferative response of splenocytes to the T-cell mitogen, concanavalin A (ConA), as well as their production of IL-2 and IFN-gamma, was decreased dose-dependently following exposure of mice to DEP for 2 weeks, whereas proliferation was not changed in response to anti-CD3 monoclonal antibody. In summary, short-term respiratory exposure of mice to DEP resulted in systemic immunosuppression with evidence of T cell-mediated and possibly macrophage-mediated mechanisms. 相似文献
6.
Fernando Kemta Lekpa Souha?bou Ndongo Jo?lle Tiendrebeogo Awa Cheikh Ndao Abdikarim Daher Abdoulaye Pouye Mamadou Mourtalla Ka Thérèse Moreira Diop 《Clinical rheumatology》2012,31(11):1617-1620
Several studies have suggested that rheumatoid arthritis (RA) is uncommon in rural sub-Saharan Africa. The aim of this study is to determine the potential differences between patients with RA living in rural areas and those living in urban areas. We performed a cross-sectional study from June 2006 to May 2009. We included all patients with RA (1987 ACR criteria) seen at the Rheumatology Unit of the Le Dantec Teaching Hospital, Dakar, Senegal. We compared the main socio-demographic and clinical characteristics of patients living in rural areas to those living in urban areas. We included 180 patients in our study, of whom, 143 (79.4?%) lived in urban areas and 37 (20.6?%) in rural areas. The median age was 44?years [range 34–55] in patients from rural areas vs. 41?years [range 30–53] in patients from urban areas, without any statistical significance (p?=?0.24). Patients under the age of 60 mostly lived in urban areas (p?=?0.03). The extra-articular manifestations were significantly more frequent in patients living in rural areas (p?=?0.02). There was no statistical significance when comparing the delay in diagnosis, number of swollen joints, disease activity, hand deformities, and concentration of autoantibodies (RF and ACPA) in both populations. The percentage of patients seen from the rural areas of Senegal is low (20.6?%) compared to those seen from the urban areas. The number of extra-articular manifestations is the main difference between patients living in rural and urban areas. The role played by environmental factors seems important. Further incidence studies are needed. 相似文献
7.
Yang CY Chen YF Lee CW Huang A Shen Y Wei C Liu HM 《AJNR. American journal of neuroradiology》2008,29(7):1288-1295
BACKGROUND AND PURPOSE: Conventional CT angiography (CTA) is acquired during only a short interval in the arterial phase, which limits its ability to evaluate the cerebral circulation. Our aim was to compare the image quality and radiation dose of conventional single-phase CTA (SP-CTA) with a multiphase CTA (MP-CTA) algorithm reconstructed from a perfusion CT (PCT) dataset.MATERIALS AND METHODS: Fifty consecutive patients undergoing head CTA and PCT in 1 examination were enrolled. The PCT dataset was obtained with 40.0-mm-detector coverage, 5.0-mm axial thickness, 80 kilovolt peak (kVp), 180 mA, and 30 mL of contrast medium. MP-CTA was reconstructed from the same PCT dataset with an axial thickness of 0.625 mm by using a new axial reconstruction algorithm. A conventional SP-CTA dataset was obtained with 0.625-mm axial thickness, 120 kVp, 350 mA, and 60 mL of contrast medium. We compared image quality, vascular enhancement, and radiation dose.RESULTS: SP-CTA and MP-CTA of 50 patients (male/female ratio, 31/19; mean age, 59.25 years) were analyzed. MP-CTA was significantly better than SP-CTA in vascular enhancement (P = .002), in the absence of venous contamination (P = .006), and was significantly higher in image noise (P < .001). MP-CTA used less contrast medium than SP-CTA and could demonstrate hemodynamic information. The effective dose of MP-CTA was 5.73 mSv, which was equal to that in conventional PCT, and it was 3.57 mSv in SP-CTA.CONCLUSION: It is feasible that MP-CTA may provide both CTA and PCT results. Compared with SP-CTA, MP-CTA provides comparable image quality, better vascular enhancement, hemodynamic information, and more noise with less detail visibility with a lower tube voltage. The radiation dose of MP-CTA is higher than that of SP-CTA, but the dose can be reduced by altering the sampling interval.Cerebral CT angiography (CTA) is a well-established minimally invasive diagnostic procedure used to detect cerebral aneurysms, acute vascular occlusions, or vasospasms and even predicts hematoma expansion in acute intracerebral hemorrhage.1–6 Cerebral perfusion CT (PCT) is an important tool to evaluate cerebral ischemia, infarction, cerebral vascular reserve, and microvascular permeability of intracranial neoplasms.7 With PCT, the linear relationship between contrast concentration and pixel intensity lends itself more readily to quantification of blood flow values, compared with bolus contrast MR perfusion imaging.8,9 PCT generates parametric maps of blood flow, including cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT), by using complex deconvolution algorithms.7 In a systematic review, the authors concluded that the most accurate assessment of the site of occlusion, infarct core, salvageable brain tissue, and collateral circulation in patients suspected of acute stroke is by a combination of PCT and CTA.10 Compared with the dose used for single-detector-row CT, thin-section, multidetector CT (MDCT) requires an increased radiation dose for both CTA and PCT examinations.11–13 To attain an “as low as reasonably achievable radiation dose,” many techniques have been tried to optimize radiation-dose levels in MDCT CTA.Currently, most commercialized CT scanners provide axial scanning in maximum z-axis coverage of 40-mm (2.5 mm × 16) sections; thin-thickness reconstruction modes can be scanned in 20-mm (0.625 mm × 32) sections. During acquisition of conventional CTA, only a short interval in the arterial phase is taken for reconstruction. We call this “single-phase CTA” (SP-CTA). During PCT examinations, to evaluate the area of attenuation change, we acquired axial scans of sequential images at the same level in a fixed or variable time interval (ie, multiphase mode). With the increasing scanning speed of CT, the time interval can be reduced to 0.5 second in state-of-the-art MDCT. Scanning coverage is still a problem because of the cone beam geometry in current MDCT. The fully sampled region, the region covered by every view in the scanning, is less than the cylinder, with a height equal to the detector isocenter coverage.14,15 To overcome this problem, we used extrapolation during the back projection process. The cone beam effect increases farther away from the isocenter and becomes more prominent with a larger FOV. Under such conditions, a novel vendor reconstruction algorithm has been developed to solve the cone beam effect, conducting a 40-mm beam of 64i × 0.625 mm in an axial scanning. We can then obtain raw data of thin-section PCT and perform postprocessing to reconstruct CTA from this thin-section PCT. Because such CTA images contain data from different time points, we call the technique “multiphase CTA” (MP-CTA), in contrast to conventional single-phase (SP-CTA). This study was designed to compare the image quality and radiation dose of MP-CTA by using the novel thin-reconstruction algorithm from the PCT dataset with the SP-CTA data from the same patient. 相似文献
8.
The purpose of the study is to propose a simple and reproducible test for assessing nerve damage in leprosy. It is applied to the sensory branch of the radial nerve of leprosy patients, prior to any treatment. Skin sensitivity is measured by means of a needle, a drop of ether and some calibrated filaments. These three tests are collated and compared with the results of electromyographic examination of the nerve. The filament calibrated to 0.2 grams gives optimum sensitivity (0.79) and excellent specificity (0.95) in relation to the electromyographic test. Its routine use in the field is simple and reproducible and should result in a greater number of patients receiving the treatment they need. 相似文献
9.