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排序方式: 共有1354条查询结果,搜索用时 31 毫秒
1.
The expression of alpha melanocyte stimulating hormone (MSH) has been investigated in two variants of the B16 murine melanoma. The presence of MSH was demonstrated by immunohistochemical methods using anti-MSH antibodies. The low metastasis variant B16-F1, which grows as an encapsulated non-invasive tumour, showed no alpha-MSH immunoreactivity. In contrast, the high metastasis variant BL6 was found to be alpha-MSH positive and the immunoreactivity was found predominantly in the peripheral invading zones of the tumour.  相似文献   
2.
Nutrition and exercise are an integral part of the medical management of many chronic and complex conditions. They are interrelated and share many common metabolic pathways that may affect disease processes and their management. In nephrology, nutritional interventions have been relatively well studied and are recommended in many evidence-based clinical practice guidelines for managing people with chronic kidney disease (CKD). Over the past 20 years, growing evidence has suggested that aerobic exercise interventions are efficacious, and that the rationale for progressive resistance training (PRT) is strong, particularly in this population, despite a more limited evidence base to date. In the small number of clinical trials that have included patients with CKD, PRT programs have proved safe, feasible to administer, and efficacious. They have been shown to improve clinical, physical, and functional outcomes.  相似文献   
3.
The Distally Based Sural Artery Flap for Ankle and Foot Coverage   总被引:1,自引:0,他引:1  
The sural artery flap is a distally based fasciocutaneous flap that has many advantages to offer for coverage in the foot and ankle area. It has the largest arc of rotation of all the regional flaps and does not require sacrifice of any major artery, and moderate-to-large-sized defects can be covered adequately. The dissection technique is simple, and donor site morbidity is minimal. We report our experience with 17 cases. Age range was from 13 to 56 years. Ten (59%) defects were posttraumatic, 3 (17%) were related to reconstructive surgery of the foot or tendon Achilles', 2 (11%) resulted from tumor resection, and 1 each were from infection and gunshot wound. The smallest flap was 6 x 4 cm and the largest was 15 x 12 cm, with the average size being 11 x 7.5 cm. In 5 cases, the donor site was closed primarily, and in other cases, split-thickness skin graft was needed. The short saphenous vein was included in the pedicle in all cases. There was no incidence of complete flap necrosis. Follow-up ranged from 3 to 30 months. Two cases (12%) developed partial superficial necrosis. In 1 case, there was partial wound dehiscence that needed debridement and repair. Another case had postoperative discharge, which subsided after removal of the calcaneal plate. None of the patients complained of any functional problem related to loss of sensation along the lateral border of the foot. The sural island flap is a reliable, safe, and easy method of providing soft tissue coverage in the area of the foot and ankle.  相似文献   
4.
BACKGROUND: Intranasal corticosteroids are recommended as first-line therapy for the treatment of allergic rhinitis. Fluticasone furoate is a novel enhanced-affinity glucocorticoid for the treatment of allergic rhinitis. OBJECTIVE: To compare the efficacy and safety of intranasal fluticasone furoate with those of vehicle placebo nasal spray in adult and adolescent patients with perennial allergic rhinitis (PAR). METHODS: After screening (7-14 days), patients 12 years and older with confirmed PAR were randomized to receive fluticasone furoate, 110 microg once daily, or placebo once daily intranasally for 4 weeks in this double-blind, multicenter study. The primary end point was mean change from baseline during the entire treatment period in daily reflective total nasal symptom score (rTNSS), recorded on diary cards by patients, using a 4-point categorical scale. RESULTS: The mean reduction from baseline during the treatment period in daily rTNSS was significantly greater in fluticasone furoate recipients than in placebo recipients (P = .005). This finding was supported by significantly greater mean reductions in morning rTNSS and evening rTNSS (P = .004 and P = .011, respectively). A significantly greater mean reduction in instantaneous morning predose TNSS with fluticasone furoate compared with placebo (P = .006) confirmed the efficacy of once-daily administration. Fluticasone furoate was also significantly more effective than placebo in overall response to therapy (P = .005). CONCLUSIONS: Fluticasone furoate nasal spray, 110 microg once daily, effectively relieved nasal symptoms of PAR in adults and adolescents 12 years and older.  相似文献   
5.
The relationship between chronic lymphocytic thyroiditis (CLT) and papillary thyroid carcinoma (PTC) is a subject of controversy. Some investigators suggest a causal relationship, whereas others regard the two as only a coincidental occurrence. An additional complicating factor is the presence of atypical nuclei frequently found within lymphoid infiltrates in CLT, which resemble those in PTC. The finding of the RET-PTC translocations in CLT has been reported by two independent groups of investigators, suggesting that the areas of nuclear atypia in CLT are neoplastic rather than reactive. In the present study, we report additional molecular findings that support the hypothesis that the atypical nuclear changes in CLT may be preneoplastic or neoplastic. We microdissected small areas with atypical nuclei in glands with CLT and observed loss-of-heterozygosity mutations of tumor suppressor genes. These genetic mutations are evidence of clonal preneoplastic or neoplastic changes in the follicular cells of CLT. The clinical malignant potential of these minute foci is likely to be very small but remains to be determined.  相似文献   
6.
Decorin is a small proteoglycan that binds to transforming growth factor-beta (TGF-beta) and inhibits its activity. However, its interaction with platelet-derived growth factor (PDGF), involved in arterial repair after injury, is not well characterized. The objectives of this study were to assess decorin-PDGF and decorin-PDGF receptor (PDGFR) interactions, the in vitro effects of decorin on PDGF-stimulated smooth muscle cell (SMC) functions and the in vivo effects of decorin overexpression on arterial repair in a rabbit carotid balloon-injury model. Decorin binding to PDGF was demonstrated by solid-phase binding and affinity cross-linking assays. Decorin potently inhibited PDGF-stimulated PDGFR phosphorylation. Pretreatment of rabbit aortic SMC with decorin significantly inhibited PDGF-stimulated cell migration, proliferation, and collagen synthesis. Decorin overexpression by adenoviral-mediated gene transfection in balloon-injured carotid arteries significantly decreased intimal cross-sectional area and collagen content by approximately 50% at 10 weeks compared to beta-galactosidase-transfected or balloon-injured, non-transfected controls. This study shows that decorin binds to PDGF and inhibits its stimulatory activity on SMCs by preventing PDGFR phosphorylation. Decorin overexpression reduces intimal hyperplasia and collagen content after arterial injury. Decorin may be an effective therapy for the prevention of intimal hyperplasia after balloon angioplasty.  相似文献   
7.
We present a case of a malignant phyllodes tumor metastasizing to a Hürthle cell adenoma of the thyroid. A 55-year-old woman underwent mastectomy for a malignant phyllodes tumor. Two years later, she presented with a left thyroid mass, which was a single, circumscribed, soft, deep red-brown nodular lesion with an eccentric area of firmer consistency. Histologically, the thyroid tumor was composed of 2 distinct types of cellular proliferation. Atypical spindle cells were infiltrating between the Hürthle cell cords and follicles in a fibrosarcomatous pattern. A battery of immunohistochemical stains was applied to both the thyroid and breast tumors for comparison. Based on the histologic and immunophenotypic features of the fibrosarcomatous components of both the breast and thyroid tumors, we rendered a diagnosis of cystosarcoma phyllodes metastatic to Hürthle cell adenoma. To the best of our knowledge, this unusual case is a first report of tumor-to-tumor metastasis of a sarcoma to a primary thyroid neoplasm.  相似文献   
8.
Spinal and bulbar muscular atrophy (SBMA) is an adult-onset motor neuron disease, caused by the expansion of a trinucleotide repeat (TNR) in exon 1 of the androgen receptor (AR) gene. This disorder is characterized by degeneration of motor and sensory neurons, proximal muscular atrophy, and endocrine abnormalities, such as gynecomastia and reduced fertility. We describe the development of a transgenic model of SBMA expressing a full-length human AR (hAR) cDNA carrying 65 (AR(65)) or 120 CAG repeats (AR(120)), with widespread expression driven by the cytomegalovirus promoter. Mice carrying the AR(120) transgene displayed behavioral and motor dysfunction, while mice carrying 65 CAG repeats showed a mild phenotype. Progressive muscle weakness and atrophy was observed in AR(120) mice and was associated with the loss of alpha-motor neurons in the spinal cord. There was no evidence of neurodegeneration in other brain structures. Motor dysfunction was observed in both male and female animals, showing that in SBMA the polyglutamine repeat expansion causes a dominant gain-of-function mutation in the AR. The male mice displayed a progressive reduction in sperm production consistent with testis defects reported in human patients. These mice represent the first model to reproduce the key features of SBMA, making them a useful resource for characterizing disease progression, and for testing therapeutic strategies for both polyglutamine and motor neuron diseases.  相似文献   
9.
The role of intraoperative frozen section in certain organ systems such as the thyroid continues to be problematic. In many cases, diagnoses are deferred or nonhelpful—“follicular lesion.” In the modern era, the widespread use of preoperative aspiration biopsy has allowed for more careful selection of patients who undergo thyroid surgery. In many cases, the fine-needle-aspiration (FNA) biopsy diagnosis can be definitive or can guide the specific surgical procedure. The literature supports our approach, which is summarized as follows: Intraoperative consultation is not needed on the intrathyroidal nodule if a preoperative FNA was definitive for papillary carcinoma. Frozen section is of no value in the intraoperative diagnosis of lesions diagnosed on FNA as “follicular neoplasm” or “Hürthle cell neoplasm” because the characterization of these lesions requires detailed analysis of the tumor capsule for the demonstration of capsular and/or vascular invasion—an analysis that is not practical in the intraoperative setting. Finally, intraoperative consultation including frozen section and intraoperative cytologic examination is most useful in those cases that are diagnosed as suspicious for papillary carcinoma by FNA, because the assessment of nuclear features needed for the definitive diagnosis is possible with intraoperative techniques in a significant number of cases.  相似文献   
10.
Amyloid fat pad aspiration specimens for cases with a clinical suspicion of amyloid typically are stained with Congo red and examined by brightfield microscopy. Congophilia with apple-green birefringence by polarization microscopy (PM) is considered diagnostic for amyloid. Examination of Congo red-stained slides by fluorescent microscopy (FM) is considered by some to be a more sensitive detection method. In this study, we assessed the utility of this technique in cytopathology archival slides from abdominal fat pad aspirations previously stained with Congo red dye. Seventy-eight cases of abdominal fat pad aspirations collected during the last 5 yr and stained with the Congo red procedure were obtained from archival files. Additionally, 20 adipose tissue material slides prepared from the surgical pathology specimens were examined as controls. One representative smear was examined in each case using FM equipped with rhodamine excitation/absorption (540/570 nm) filters. Relevant clinical information was obtained in all cases. Twelve cases (15.4%) of the 78 fat pad aspiration cases were reported originally as positive by Congo red stain using polarization and apple-green birefringence as diagnostic criteria. On review, four cases were deemed unsatisfactory. By FM examination 29 of the 74 (39.2%) cases were reclassified as positive for amyloid. The results were confirmed by immunohistochemical stain for amyloid P protein and electron microscopy. A number of similar distinct fluorescence and immunohistochemical patterns were recognized in the positive cases. Minimally weak fluorescence in the adipose tissue was observed in the control cases. The use of FM in Congo red-stained fat pad smears can improve the detection of amyloid in cytology preparations.  相似文献   
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