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81.
The nitric oxide synthase (NOS) inhibitors, L-omega-nitro-L-arginine methyl ester (L-NAME; 25 mg/kg and 100 mg/kg) and N(G)-nitro-L-arginine (L-NNA; 100 mg/kg) were used to investigate the role of NO on in vivo skeletal muscle and jejunal (mucosa and seromuscular layer) protein synthesis rates in normal (ie, untreated) and ethanol-dosed (75 mmol/kg body weight) rats. Fractional rates of protein synthesis, ie, percentage of protein pool renewed each day, k(s), %/d) were measured with a flooding dose of L-[(3)H-4]phenylalanine. In response to both doses of L-NAME and L-NNA, k(s) in skeletal muscle of normal rats decreased by 9% to 31% (P between <.05 and <.001). In the mucosa, k(s) was significantly reduced only by the higher dose of L-NAME (-49%, P <.001). In the seromuscular layer, k(s) was reduced by 15% to 57% (P between <.05 and <.001) in response to both doses of L-NAME and L-NNA. Ethanol dosage reduced k(s) in skeletal muscle (-35%, P <.001), and small reductions also occurred in the jejunal mucosal and seromuscular layers (-14% P <.05 and -12% P <.05, respectively). However, in the presence of L-NAME, ethanol reduced k(s) in jejunal mucosal and seromuscular layers by -35% (P <.01) and -30% (P <.01), respectively, compared with controls. This exacerbating effect of L-NAME predosage in ethanol-treated rats was not demonstrable in skeletal muscle. The data thus suggest that (1) endogenous NO facilitates constitutive skeletal muscle and jejunal protein synthesis in control animals in vivo; (2) the sensitivity of jejunal (but not skeletal muscle) protein synthesis to acute ethanol is increased when inhibitors of NOS are used. This tentatively implies that, in response to ethanol, overproduction of NO is not involved in the ethanol-induced reduction of protein synthesis in skeletal muscle or the jejunum.  相似文献   
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83.
Primary systemic amyloidosis   总被引:2,自引:0,他引:2  
Opinion statement Primary amyloidosis is a plasma cell dyscrasia in which insoluble immunoglobulin light chain fragments are produced and polymerize into fibrils that deposit extracellularly, causing visceral organ dysfunction and death. The disorder is rare. Its recognition requires understanding the association between nephrotic syndrome, cardiomyopathy, peripheral neuropathy, and hepatomegaly with amyloidosis. The most important screening test for amyloidosis is immunofixation of the serum and urine to detect a monoclonal immunoglobulin light chain. All patients need the diagnosis confirmed histologically. The least invasive source of tissue for amyloid detection is the subcutaneous fat. The most important prognostic factor is whether there is cardiac involvement, which is best assessed by echocardiography with Doppler studies. Therapies used include oral melphalan/prednisone and high-dose corticosteroids. High-dose chemotherapy followed by stem cell reconstitution seems to provide the highest reported response rates. Transplant is associated with unique morbidities not seen in the transplantation of patients with other hematologic malignancies.  相似文献   
84.
Chromosome 13 abnormalities (Delta13) have been associated with an unfavorable prognosis in patients with multiple myeloma (MM). The significance of this has been unresolved because of diverse methods of detection and heterogeneous groups of patients. We conducted a study of Delta13 in patients entered into the Eastern Cooperative Oncology Group trial E9486/E9487. Patients with newly diagnosed MM (median follow-up of survivors >100 months) were studied for Delta13, using bone marrow samples obtained at study enrollment. We used interphase fluorescence in situ hybridization with the probes LSI13 (Rb)/D13S319 with simultaneous immunofluorescence detection of bone marrow plasma cells (PCs). We detected Delta13 in 176 of 325 (54%) evaluable patients. Patients with Delta13 were more likely to have a serum monoclonal protein at a concentration < or =1 g/dl (22 versus 13%; P = 0.04), light-chain-only MM (19.3 versus 10.8%; P = 0.04), gamma light chain (42 versus 28%; P = 0.027), stage III (56 versus 42%; P = 0.014), and be female (60 versus 50%; P = 0.087). The PC labeling index and Delta13 correlated (P = 0.03). Patients with Delta13 were less likely to respond to treatment (74 versus 63%; P = 0.041) and had a significantly shorter median overall survival (34.9 versus 51 months; P = 0.021). The association of Delta13 and survival remained an independent prognostic variable in a regression model. Among patients with Delta13, those receiving IFN had a worse overall survival that those not receiving the medication (P = 0.03). The presence of Delta13 is an important and independent adverse prognostic factor in newly diagnosed MM and is associated with specific biological features.  相似文献   
85.
High parity, early age at first full-term pregnancy (FTP), and long-term oral contraceptive (OC) use increase cervical cancer risk, but it is unclear whether these variables are also associated with increased risk of acquisition and persistence of human papillomavirus (HPV) infection, the main cause of cervical cancer. Information on reproductive and menstrual characteristics and OC use were collected from 14 areas worldwide, among population-based, age-stratified random samples of women aged 15 years or older. HPV testing was done using PCR-based enzyme immunoassay. Unconditional logistic regression was used to estimate the odds ratios (OR) of being HPV-positive according to reproductive and menstrual factors and corresponding 95% confidence intervals (CI). When more than two groups were compared, floating CIs (FCI) were estimated. A total of 15,145 women (mean age, 40.9 years) were analyzed. Women with >or=5 FTPs (OR, 0.90; 95% FCI, 0.76-1.06) showed a similar risk of being HPV-positive compared with women with only one FTP (OR, 1.00; 95% FCI, 0.86-1.16). However, nulliparous women showed an OR of 1.40 (95% CI, 1.16-1.69) compared with parous women. Early age at first FTP was not significantly related to HPV positivity. HPV positivity was similar for women who reported >or=10 years of use of OCs (OR, 1.16; 95% FCI, 0.85-1.58) and never users of OCs (OR, 1.00; 95% FCI, 0.90-1.12). Our study suggests, therefore, that high parity, early age at first FTP, and long-term OC use are not associated with HPV prevalence, but rather these factors might be involved in the transition from HPV infection to neoplastic cervical lesions.  相似文献   
86.
The Currarino triad is a complex anomaly consisting of an anorectal malformation, a sacral bone defect and a presacral mass. It was first described in 1981 and since then, approximately 250 cases have been reported. Radiology has an important part to play in the diagnosis of this entity, as the imaging features are characteristic. We report a case of Currarino triad in an infant who presented with intractable constipation and discuss relevant MRI and plain radiography findings.  相似文献   
87.
Angiogenesis is the formation of new blood vessels and occurs physiologically during embryonal growth, wound healing and during the menstrual cycle. It is essential for the proliferation and metastases of most malignant neoplasms. Recent evidence suggests that angiogenesis is increased in multiple myeloma and has prognostic value in the disease. Angiogenic cytokines such as vascular endothelial growth factor (VEGF) and basic fibroblast growth factor are expressed by myeloma cells and appear to play a role in the increased angiogenesis seen in myeloma. In addition, VEGF may serve as a paracrine growth factor for myeloma cells.Based on the increased angiogenesis observed in myeloma, thalidomide has been studied as antiangiogenic therapy. Although its mechanism of action in myeloma is still unclear, thalidomide appears to be active in 25-30% of patients with refractory myeloma. Major toxicities include constipation, sedation, skin rash, fatigue, and peripheral neuropathy. Studies are ongoing to determine its role as initial treatment for myeloma. This paper reviews the available data on angiogenesis in myeloma, and summarizes the role of thalidomide therapy in this disease. The pharmacology and toxicity of thalidomide are also discussed.  相似文献   
88.
Waldenstr?m's macroglobulinemia is a low-grade lymphoplasmacytic lymphoma. It has an overall incidence of 2.5/million/year. The median age at diagnosis is 63 years. The clinical manifestations are hepatomegaly (20%), splenomegaly (15%), and lymphadenopathy (15%). The most common symptom is fatigue related to a normochromic, normocytic anemia, and the median hemoglobin value at diagnosis is 10 gm/dl. All patients with Waldenstr?m's macroglobulinemia have a circulating tumor marker, the monoclonal IgM protein. Occasionally high levels of the IgM monoclonal protein can produce a hyperviscosity syndrome manifested by oronasal bleeding. Occasionally retinal hemorrhage or serious neurologic complications, such as somnolence or coma, may occur. The most important prognostic factors are hemoglobin, age, weight loss, and a cryoglobulin. Therapy has included alkylating agents, particularly chlorambucil, purine nucleoside analogs such as fludarabine or cladribine, and most recently the use of rituximab. The median survival of symptomatic patients is 65 months. Patients without symptoms should not be treated.  相似文献   
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90.
BACKGROUND: Expanded polytetrafluroethelyne (e PTFE, Gore-Tex(R)) has been advocated as an implant material for medialization of the vocal fold. Animal studies involving rabbits and a porcine model have demonstrated host tolerance of the implant. There have been no reports describing the histological changes in a human laryngectomy specimen with a Gore-Tex implant. CASE PRESENTATION: The histological findings in a laryngectomy specimen of a patient previously implanted with e PTFE for medialization of a paralyzed vocal fold following excision of a vagal neurofibroma were studied.Histopathology revealed a mild foreign-body giant cell granulomatous reaction with some associated fibrosis. The granulomatous response was limited to the periphery of the Gore-Tex and although it closely followed the profile of the material it did not encroach into or significantly break up the material. There was no significant neutrophilic or lymphocytic inflammation. CONCLUSIONS: Our findings are consistent with the animal models confirming that Gore-Tex implantation does not result in a significant granulomatous reaction in the human larynx over a 13-month period. Moreover, there is no evidence of resorption or infection. Further, the lack of lymphocytes in association with the granulomas indicates that there is no significant immunological hypersensitivity. Histologically, the slight permeation by connective tissue is similar to that seen in Gore-Tex vascular and cardiac implants. The degree of the slight giant cell response appears to be dependent on the profile of the material; a sharp edge incited more of a response than a flat surface.  相似文献   
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