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471.
Ocular pulse amplitude in a case of innominate steal syndrome.   总被引:2,自引:0,他引:2  
PURPOSE: To report an inter-eye difference of the ocular pulse amplitude (OPA) in a case of innominate steal syndrome, as measured by recording applanation tonometry. METHODS: OPA was measured in a 49-year-old male before and after percutaneous transluminal angioplasty of the innominate artery. RESULTS: Before dilation of the stenotic innominate artery, OPA was 2.00 (+/- 0.49) mm Hg in the right and 3.46 (+/- 0.53) mm Hg in the left eye. After dilation, OPA was 3.26 (+/- 0.51) mm Hg in the right eye and 3.25 (+/- 0.99) mm Hg in the left eye. CONCLUSION: Recording applanation tonometry may be useful for identifying occlusive disease of extracranial vessels in an office setting.  相似文献   
472.
Young age at diagnosis is claimed to be a prognostic factor in the natural history of breast cancer. Of 2879 patients aged < 70 years treated for primary operable breast cancer (< 5 cm diameter) at Nottingham City Hospital between 1973 and 1993, 120 were less than 35 years of age at diagnosis. Histopathological and prognostic variables were compared between patients aged < 35, 35-50 and 51-70 years. A significant reduction in metastasis disease-free survival and actuarial survival was seen in breast cancer patients aged < 35 years compared with the two older age groups. Patients aged < 35 years at diagnosis presented more frequently with high-grade cancers and vascular invasion. No differences were seen for tumour size or lymph node stage. The Nottingham Prognostic Index (NPI) was used to stratify cancers in each age group. Because of the tendency to high grade, a greater percentage of patients aged < 35 years fell into the poor-prognosis group. Within each prognostic group, no difference in actuarial survival was seen between age groups. The association of young age at diagnosis with a worse prognosis in this series is explained by a higher proportion of poorly differentiated cancers; age itself had no influence on the prognosis of the individual.  相似文献   
473.
Women previously treated for primary operable breast cancer are at increased risk of developing cancer in the contralateral breast, but the clinical significance of this development is unclear. The purpose of this study was to assess the impact of synchronous bilateral breast cancer or the development of a metachronous contralateral breast primary on the prognosis. In a series of 3210 women age < or = 70 years treated between 1975 and 1995 for primary operable breast cancer, 106 were identified to have bilateral breast cancer. Of these women, 26 were noted to have synchronous bilateral breast primaries (0.8%), and 80 developed a contralateral breast cancer after treatment for an initial primary breast cancer. Using life-tables analysis, there was a significant difference in survival between women with unilateral breast cancer, those with synchronous bilateral breast cancers, and those with metachronous contralateral breast with survivals at 16 years of 53.8%, 42.4%, and 60.1%, respectively (p < 0.0001), from the date of the diagnosis of the first primary tumor. There was no difference in survival seen between the three groups when survival was calculated from the date of diagnosis of the second primary in cases of metachronous contralateral breast cancer (p = 0.31). When contralateral breast cancer was incorporated as a time-dependent covariate in a Cox multivariate model together with the three factors used to determine the Nottingham Prognostic Index (invasive tumor size, grade, and lymph node stage), contralateral breast cancer continued to be a significant prognostic determinant (p = 0.02). The survival of women with synchronous bilateral breast cancer or metachronous breast cancers diagnosed within 2 years of the original primary was worse than those with unilateral disease. However, the time duration to metachronous contralateral breast cancer did not have prognostic significance in a multivariate model compared with the prognostic features of the original primary.  相似文献   
474.
Photomechanical transdermal delivery: the effect of laser confinement   总被引:4,自引:0,他引:4  
BACKGROUND AND OBJECTIVE: Photomechanical waves can transiently permeabilize the stratum corneum and facilitate the delivery of drugs into the epidermis and dermis. The present study was undertaken to assess the effect of pulse characteristics to the penetration depth of macromolecules delivered into the skin. STUDY DESIGN/MATERIALS AND METHODS: Photomechanical waves were generated by confined ablation with a Q-switched ruby laser. Fluorescence microscopy of frozen biopsies was used to assay the delivery of macromolecules through the stratum corneum and determine the depth of penetration. RESULTS: Photomechanical waves generated by confined ablation of the target have a longer rise time and duration than those generated by direct ablation. Confined ablation required a lower radiant exposure (from approximately 7 J/cm(2) to approximately 5 J/cm(2)) for an increase in the depth of delivery (from approximately 50 microm to approximately 400 microm). CONCLUSIONS: Control of the characteristics of the photomechanical waves is important for transdermal delivery as they can affect the depth of drug penetration into the dermis.  相似文献   
475.
476.
Farshid G  Pradhan M  Kollias J  Gill PG 《Cancer》2000,89(12):2527-2537
BACKGROUND: Many empiric protocols are used to detect metastases in sentinel lymph nodes (SLNs), but comparison of the efficacy of these methods is impractical because tissue is lost in processing, making reassessment with another policy difficult. Consequently, performance indicators of this test are largely unknown. DESIGN: The authors retrospectively examined 112 SLNs removed from 89 patients with breast carcinoma treated at the authors' institution and used the histologic data to devise a mathematic model of a SLN with Matlab modeling software. The authors simulated examination of this computer-generated (virtual) lymph node according to several macroscopic and histologic sampling protocols and for each protocol assessed the probability of detecting micrometastases of specified sizes. The authors used published costing figures to estimate the cost of the policies. RESULTS: Direct comparison of 6 sectioning strategies currently in use by pathology laboratories showed the chances of detecting a 500-microm metastasis ranged from 20% to 75%. Four of the 6 protocols had a less than 30% chance of detecting metastases of this size. The detection rate of smaller metastases was poorer. Cost was not a good discriminator because some policies were more efficient than others. CONCLUSIONS: The detection of metastases is highly dependent on the methods used to look for them. The authors' simulations suggest that commonly used methods of examining lymph nodes have high false-negative rates, particularly for small metastases. There is an urgent need for pathologists and clinicians to agree on the minimum size of SLN metastases that will be sought by histology and set standard methods for examining these lymph nodes.  相似文献   
477.
BACKGROUND: Dihydroxyacetone (DHA), a colorless sugar in "sunless" tanning lotions, binds to stratum corneum to form a UV-A-protective brown pigment. Bound DHA polymer is shed faster from hyperproliferative skin sites such as psoriatic plaques. We tested the hypothesis that selective shedding of DHA pigment during psoralen-UV-A (PUVA) treatment of psoriasis may allow higher UV-A doses, thus accelerating clearing while protecting uninvolved skin. Concurrent use of lactic acid was investigated as an aid in removing scale and residual DHA from psoriatic plaques. OBSERVATIONS: Thirty psoriatic patients with more than 20% body surface area involvement were recruited. The 6 PUVA study groups were (1) standard American style, (2) American style plus lactic acid, (3) DHA-PUVA or "topical ultraviolet-resisting barrier to optiimize PUVA" (Turbo-PUVA), (4) Turbo-PUVA with lactic acid, (5) European style, and (6) European style plus DHA. Combinations of lactic acid and European-style treatment were not studied. Each subject received up to 30 oral PUVA treatments twice weekly 3 days apart. The DHA-PUVA groups used 15% DHA lotion twice weekly. Lactic acid groups used 7% lotion daily except on treatment days. Psoriasis area and severity index scores were recorded weekly. Turbo-PUVA allowed higher UV-A exposures with minimal burns, showed faster clearing, and required fewer treatments for 90% clearing (P<.001). CONCLUSIONS: Protection of uninvolved skin by DHA during PUVA treatment allows higher UV-A exposures to be tolerated, demonstrates faster clearing, and requires fewer treatments to clear psoriasis. By reducing the total body dose received, Turbo-PUVA may also reduce long-term risks.  相似文献   
478.
The arthritogenic activities of tumor necrosis factor (TNF) and its p55TNF-receptor (R) have been well documented in experimental animal models of arthritis, and in transgenic mice expressing wild-type or mutant transmembrane human TNF proteins in their joints. In this study we show that chronic inflammatory arthritis also develops in transgenic mice made to overexpress a mutant transmembrane from of the murine TNF protein (muTNFΔ1–12) which is known to utilize efficiently both the p55 and the p75TNFR. Cross-breeding of the transgene into a TNF knockout background did not alter development of disease. Analysis of TNF bioactivity in sera from lipopolysaccharide-stimulated mice or ex vivo macrophage cultures demonstrated that the muTNFΔ1–12 protein accumulates on the cell surface and is not processed to bioactive soluble TNF, indicating that transmembrane TNF is by itself sufficient to mediate pathogenesis of arthritis. Furthermore, using TNFR knockout mice, it is shown that development of transmembrane TNF-mediated arthritis requires the presence of the p55TNFR but is significantly delayed in the absence of the p75TNFR, suggesting a positive cooperation between the two TNFR in the arthritogenic process. These results indicate that blocking the activities of both soluble and transmembrane TNF may be required to effectively neutralize the pathogenic potential of this cytokine in arthritis.  相似文献   
479.
480.
Local bone erosion and systemic bone loss are hallmarks of rheumatoid arthritis and cause progressive disability. Tumor necrosis factor (TNF) is a key mediator of arthritis and acts catabolically on bone by stimulating bone resorption and inhibiting bone formation. We hypothesized that the concerted action of anti-TNF, which reduces inflammation and parathyroid hormone (PTH), which stimulates bone formation, or osteoprotegerin (OPG), which blocks bone resorption and could lead to repair of local bone erosions and reversal of systemic bone loss. To test this, human TNF-transgenic mice with established erosive arthritis and systemic bone loss were treated with PTH, OPG, and anti-TNF, alone or in combination. Local bone erosions almost fully regressed, on combined treatment with anti-TNF and PTH and/or OPG, suggesting repair of inflammatory skeletal lesions. In contrast, OPG and anti-TNF alone led to arrest of bone erosions but did not achieve repair. Treatment with PTH alone had no influence on the progression of bone erosions. Local bone erosions all showed signs of new bone formation such as the presence of osteoblasts, osteoid formation, and mineralization. Furthermore, systemic bone loss was completely reversed on combined treatment and this effect was mediated by osteoblast stimulation and osteoclast blockade. In summary, we conclude that local joint destruction and systemic inflammatory bone loss because of TNF can regress and that repair requires a combined approach by reducing inflammation, blocking bone resorption, or stimulating bone formation.  相似文献   
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