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排序方式: 共有1076条查询结果,搜索用时 31 毫秒
1.
HOCK LEONG EE MBBS MRCP CHEE LEOK GOH MBBS FRCP KHOO ES-Y. CHAN PHD POR ANG MBBS MRCP 《Dermatologic surgery》2006,32(1):34-40
BACKGROUND: Acquired bilateral nevus of Ota-like macules (Hori's nevus) is a common dyschromatosis among Asian women. Q-switched lasers have been used successfully as a treatment modality. OBJECTIVE: The purpose of this study was to compare the efficacy of using the Q-switched 532 nm neodymium:yttrium-aluminum-garnet (Nd:YAG) laser followed by the 1,064 nm laser versus the Q-switched 1,064 nm Nd:YAG laser alone in the treatment of Hori's nevus. METHODS: This is a prospective left-right comparative study. Ten women with bilateral Hori's nevus were recruited and treated with a combination of the Q-switched 532 and 1,064 nm Nd:YAG lasers on the right cheek and the Q-switched 1,064 nm Nd:YAG laser alone on the left cheek. Only one laser treatment session was performed. The degree of pigmentation was objectively recorded with a mexameter. Subjective assessment was made by both patients and two blinded, nontreating dermatologists. RESULTS: At 6 months, there was a statistically significant difference (p = .009) of 35.10 points using objective mexameter measurements between the two sides, favoring the side treated with a combination of 532 and 1,064 nm laser treatment. Subjective grading by the patients and blinded dermatologists also confirmed that combination therapy was more successful after one treatment. Although combination treatment had a higher incidence of mild postinflammatory changes, this disappeared within 2 months. CONCLUSIONS: Concurrent use of the Q-switched 532 nm Nd:YAG laser in combination with the 1,064 nm laser is more effective in pigment clearance than the Q-switched 1,064 nm Nd:YAG laser alone for Hori's nevi. 相似文献
2.
In mycelia of Streptomyces granaticolor grown in liquid cultures the distribution of DNA was surveyed by staining and autoradiographic methods. The frequency of stained nucleoids was rather similar in young and old hyphal regions. However, the size of the nucleoids increased with the age of a hyphal region. The degree of heterogeneity in nucleoid size was particularly high during slow growth. In the autoradiograms silver grains (3H-thymidine label) were also heterogeneously distributed along the hyphae. Calculation of the average number of silver grains per nucleoid revealed that the amount of DNA per nucleoid was 1.6 times higher in the more distant subapical regions than within the 35 μm long apical region. From a chase experiment it became obvious that the DNA segregated in a normal manner only within the apical region. When the chase lasted for one doubling time, the frequency of silver grains was reduced to 50% only within the about 30 μm long apical region. The label incorporated subapieally remained almost constant, therefore, indicating a lack of normal segregation. Only about 10% of the label was lost by branching. The lack of segregation of sister nucleoids after repeated rounds of replication was found to be responsible for the increase of nucleoid size within subapieal hyphal regions. 相似文献
3.
Considerable variations in the suppression of graft-versus-host disease with monoclonal anti-Thy-1 antibodies were found to relate to substantial differences noted in the expression of mouse Thy-1 marker on lymph node and spleen cells of Thy-1.1 (AKR/J, C57BL/6.Thy-1.1) and Thy 1.2 (AKR/Cu, C57BL/6) mice. Thy-1.1 mice showed a population of 22% (AKR/J) or 13% (C57BL/6-Thy-1.1) of Thy-1 negative cells among peripheral T cells carrying Ly-1 marker. This was in sharp contrast with Thy-1.2 mice, where as expected practically all peripheral T cells expressed both Thy-1 and Ly-1. Double-marker analysis on FACScan revealed that the Thy-1-/Ly-1+ cell population identified in Thy-1.1 but not in Thy-1.2 mice doubtless represents T cells because they express CD3 and either the L3T4 (CD4) or Lyt2 (CD8) phenotype. Using quantitative fluorescence-measurement techniques, it was found in addition that the Thy-1 antigen-binding sites on Thy-1+ cells from Thy-1.1 mice are considerably fewer than those present in Thy-1.2 mice. In fact, the Thy-1 antigen-binding sites approximate the level of Ly-1 density. Consequences of the reduced expression of Thy-1 became apparent in vivo: (1) lymphnode and splenic T cell areas in Thy-1.1 mice were clearly less depleted when Thy-1.1 and Thy-1.2 mice had been injected with rat IgG2b anti-Thy-1 mAb; and (2) GvHD was prevented completely in fully mismatched mice by anti-Thy-1 mAb if the donor mice expressed Thy-1.2 but was barely delayed if the donors expressed Thy-1.1. Thus the present study provides a transplantation model for comparing differences in T antigen density and their consequences for antibody-induced immunosuppression. 相似文献
4.
Serial radionuclide studies using both Tc-99m DTPA (perfusion) and I-131 hippuran (tubular function) were correlated with histologic findings in 25 patients with renal transplants. These cases included 15 cases of cyclosporin-A nephrotoxicity (CsA-NT) and ten cases of acute cellular rejection that were retrospectively selected on the basis of biopsy findings and favorable clinical response to therapy specific for each of these conditions. The serial radionuclide studies enabled the correct diagnosis in 12 of 15 cases of CsA-NT and eight of ten cases of acute rejection. Posttherapy radionuclide studies, furthermore, demonstrated improvement consistent with clinical response. In all cases, the radionuclide results were available at least 24 hours before biopsy findings. These results indicate that serial radionuclide studies evaluating interval changes in both perfusion and tubular function are of significant value in the diagnosis and follow-up of CsA-NT and acute cellular rejection in transplant recipients. This initial experience suggests a sensitivity of 80%. 相似文献
5.
Markus Donix Bettina Beuthien-Baumann Rüdiger von Kummer Georg Gahn Fatima Thomas Vjera Holthoff 《Journal of clinical neuroscience》2007,14(6):601-603
Waldenstrom's macroglobulinemia (WM) is an uncommon low-grade lymphoma. Cognitive impairment due to central nervous system infiltration by lymphoplasmocytoid cells (Bing-Neel syndrome) has been rarely reported. We describe a 54-year-old man who was referred to a memory disorder clinic with a 9-month history of clinically obvious nonfluent aphasia and WM. He underwent extensive neuropsychological testing, clinical examination and structural and functional brain imaging. The diagnosis of the diffuse form of the Bing-Neel syndrome was supported by abnormal lymphoid cells found in the cerebrospinal fluid. Structural and functional brain imaging revealed impairment of brain areas due to white matter changes and subsequent functional deficits mimicking the neuropsychological syndrome encountered in progressive nonfluent aphasia. The diffuse form of Bing-Neel syndrome and neurological deficits are assumed to be the result of leptomeningeal infiltration by malignant cells and/or neoplastic vascular obstruction. 相似文献
6.
Birgit Herting MD Bettina Beuthien‐Baumann MD Katrin Pöttrich PhD Markus Donix MD Antje Triemer PhD Johannes B. Lampe MD Rüdiger von Kummer MD Karl Herholz MD Heinz Reichmann MD Vjera A. Holthoff MD 《Movement disorders》2007,22(4):490-497
Depressive symptoms are common in patients with neurodegenerative disorders. Imaging studies suggest that a disruption of frontal-subcortical pathways may underlie depression associated with basal ganglia disease. This pilot study tested the hypothesis that frontal dysfunction contributes to depression associated with multiple system atrophy (MSA) and progressive supranuclear palsy (PSP). Depressed patients with MSA (n = 11), PSP (n = 9), and age-matched controls (n = 25) underwent measures of cerebral glucose metabolism applying positron emission tomography with (18)F-fluorodeoxyglucose. Regional metabolism in the patient groups was compared to the normal subjects using the voxel-based statistical parametric mapping. Depressive symptom severity (Hamilton Depression Rating) and degree of locomotor disability (Hoehn & Yahr) were assessed in the patient groups. The association between prefrontal metabolism and the occurrence of depressive symptoms and the degree of locomotor disability was investigated. When compared to controls, MSA patients revealed significant metabolic decreases in bilateral frontal, parietal, and cerebellar cortex and in the left putamen. In PSP patients, significant hypometabolism was demonstrated in bilateral frontal cortex, right thalamus, and midbrain. Depression severity but not the patients' functional condition was significantly associated with dorsolateral prefrontal glucose metabolism in both patient groups. The findings of this pilot study support the hypothesis that depressive symptoms in MSA and PSP are associated with prefrontal dysfunction. 相似文献
7.
8.
This study was carried out to determine the ultrastructure and origin of previously described neurotensin-like immunoreactive (NT-LI) nerve fibres in the wall of the carotid sinus of the guinea pig. In our degeneration experiments, these NT-LI axons were unaffected by surgical sympathectomy but disappeared in response to transection of the carotid sinus nerve, thus suggesting a sensory origin. This assumption could be supported by combined retrograde tracing and immunohistochemistry. Primary afferent neurons of the sensory glossopharyngeal (petrosal) ganglion projecting to the carotid sinus were identified by injecting the retrograde fluorescent tracer, Fluoro-Gold, into the sinus wall, and some of these neurons displayed NT-LI. Within the carotid sinus, the terminals of these NT-LI sensory neurons exhibited ultrastructural features characteristic of baroreceptor endings, i.e. axonal swellings filled with mitochondria and closely associated to elastin. However, many endings also fulfilling the ultrastructural criteria for baroreceptors were devoid of immunolabelling. Thus, we conclude that the NT-LI terminals constitute a subgroup rather than the entire population of baroreceptor endings within the guinea pig carotid sinus. With respect to the established pharmacological effects of NT in guinea pig, we propose an involvement of NT-LI fibres in the modulation of baroreception at the peripheral level. 相似文献
9.
The stability of the basic unit for fixation of the Ilizarov external fixation system was tested in several loading modes. The effects of varying the number of wires and the orientation of wire placement were studied. The fixation units were mounted on a plastic, simulated, long bone and tested by loading in several directions. The Ilizarov fixation ring was found to be relatively stiff in axial compression and torsion. Its stiffness in this mode was directly proportional to the number of wires in the system and independent of the configuration of wire placement. Loading in bending and in shear provided much lower levels of stiffness, and this was dependent on the angles formed between the wires. The addition of a wire at a minimum distance of 4 cm from the primary ring significantly improved bending stiffness. The use of opposed olive wires also improved shear stiffness. 相似文献
10.
E. Kummer 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1912,116(1):301-325
Ohne Zusammenfassung
(Mit 6 Abbildungen im Text und 7 stereoskopischen Bildern in Mappe.) 相似文献