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181.
PURPOSE: The aim of the present study was to elucidate whether only local, or also systemic immunomodulatory effects may be induced by intravesical BCG therapy of superficial urinary bladder cancer. MATERIALS AND METHODS: A total of 37 patients with stages Ta to T1b superficial transitional cell bladder carcinomas received 6 weekly BCG instillations after transurethral resection of the tumor. In a first group of 19 patients blood was taken before each BCG instillation and 6 weeks after the last one. In a second group of 18 patients blood and urine was taken before and 2, 6, and 24 hours after each BCG instillation. In the mitogen-stimulated whole blood cell cultures and in the urine samples the levels of the cytokines IL-1beta, IL-2, IL-10, TNF-alpha and IFN-gamma were determined by enzymoimmunological tests. Additionally, in all plasma and urine samples the levels of TNF-p75-receptor (TNF-p75-R) were measured. RESULTS: Comparison of ex vivo leukocyte cytokine production in the blood cell cultures of the patients of group I revealed no significant change in the levels of the cytokines. In contrast, TNF-p75-R plasma levels increased significantly during the experimental time of 12 weeks (p < or =0.01). In the blood cell cultures of the group II patients a different daytime variation of cytokine production was seen, compared to the 19 healthy controls. After BCG instillation the normal peak cytokine production in the evening was suppressed. A significant rise in plasma TNF-p-75-R levels was measured 24 hours after BCG instillation (p < or =0.05). In the urine of these patients significantly higher levels of all measured cytokines and TNF-p75-R were observed 6 to 24 hours after the instillation. CONCLUSIONS: The results suggest that besides the well known local immune activation, BCG instillation also leads to a modulation of peripheral immune mechanisms.  相似文献   
182.
PURPOSE: Idiopathic detrusor overactivity has not been thoroughly investigated and its natural history remains largely anecdotal. Bladder overactivity resulting from a neurogenic, anatomical or medical condition has been well described. Therefore, we assessed the long-term results of conservative treatment of children with idiopathic symptomatic refractory detrusor instability. MATERIALS AND METHODS: We reviewed the records of 58 patients who had an isolated finding of uninhibited contractions on urodynamics performed for refractory enuresis and daytime wetting between 1988 and 1994. Study exclusion criteria were chronic urinary tract infection, neurological lesion, anatomical abnormality of the lower urinary tract and less than 12 months of followup. RESULTS: Of the 30 children who met our study inclusion criteria 26 (87%) had complete (21) or significant (5) symptom resolution. Average time to resolution was 2.7 years (range 0.2 to 6.6). Patients with a 50% to 90% bladder capacity expected for age were more likely to benefit from therapy than those with a bladder capacity outside of this range. Age and gender were not significant predictors of resolution although girls were more likely to have resolution than boys. CONCLUSIONS: Idiopathic detrusor instability is amenable to conservative management in the majority of patients during a prolonged period. We advocate thorough urological and urodynamic evaluation to identify idiopathic detrusor instability as an etiology of enuresis and daytime wetting in complicated cases.  相似文献   
183.
184.
Mood symptoms are reported frequently in asthma patients, particularly during corticosteroid therapy. This investigation compared the Internal State Scale (ISS), a self-report measure of symptoms of mania and depression, to the Hamilton Rating Scale for Depression (HRSD), Young Mania Rating Scale (YMRS), and Brief Psychiatric Rating Scale (BPRS) in a group of asthma patients (n=60 at baseline) before, during, and after a 1-2 week burst of prednisone. The depression and well being subscales of the ISS correlated well with HDRS scores. The perceived conflict subscale correlated with the BPRS scores. However, none of the ISS subscales correlated consistently and specifically with the YMRS in this population. Possible explanations for differences observed in bipolar versus asthma patients given the ISS are discussed. These data suggest the ISS may be a useful tool for depression symptoms and overall psychopathology in asthma patients and in patients receiving corticosteroid therapy. However, its ability may be attenuated outside of the population for which it was designed.  相似文献   
185.
To study the possible role of reactive oxygen species in airway hyperreactivity, we examined the effects of the superoxide anion radical (O(2)(-)) generating systems, pyrogallol and xanthine with xanthine oxidase, on muscle tone, excitatory and inhibitory neurotransmission in the cat airway. Smooth muscle contraction or non-adrenergic non-cholinergic (NANC) relaxation evoked by electrical field stimulation (EFS) were measured before or after O(2)(-) generating systems with or without diethydithiocarbamic acid (DEDTCA), an inhibitor of endogenous superoxide dismutase (SOD). Resting membrane potential or excitatory junction potential (EJP) were also measured in vitro. Both pyrogallol and xanthine/xanthine oxidase produced biphasic changes in basal and elevated (by 5-HT) muscle tone. After SOD pretreatment, both systems consistently produced a prolonged contraction, thereby indicating that O(2)(-) was converted to H(2)O(2) by the action of SOD and as a result the actions of O(2)(-) were lost but those of H(2)O(2) introduced. The O(2)(-) showed no significant effect on smooth muscle contraction or EJP evoked by EFS, however after DEDTCA pretreatment, it evoked initial enhancement followed by suppression of the contraction and EJP. DEDTCA pretreatment ameliorated the inhibitory action of pyrogallol and xanthine/xanthine oxidase on the NANC relaxation, probably because O(2)(-) could combine with endogenous NO to form peroxynitrite. These results indicate that the O(2)(-) generating systems have multiple actions, presumably due to the presence and simultaneous action of at least two different reactive oxygen species (O(2)(-) and H(2)O(2)). While H(2)O(2) seems to be responsible for elevation of muscle tone and augmentation of smooth muscle contraction by EFS, O(2)(-) inhibits muscle tone, cholinergic and NANC neurotransmission.  相似文献   
186.
Sternal infection is a devastating complication of heart surgery. It may be the result of unstable osteosynthesis, caused by the sternal wires cutting into the cortical layers, which results in tension loss and gap formation. We describe a technique that prevents the cerclages from cutting into the sternal plates and covers the sternum with a well-capillarized barrier of major pectoralis muscle.  相似文献   
187.
Targeted therapies that inhibit the activity of tyrosine kinase receptors such as the epidermal growth factor receptor (EGFR) have shown activity against solid malignancies when used as single agents or in combination with chemotherapy. Although anti-EGFR therapies are active in some patients, eventually disease in nearly all patients will become refractory to therapy. Therefore, a better understanding of the mechanisms of resistance to anti-EGFR therapies is critical to further improve the efficacy of this class of agents. Mechanisms that mediate resistance to anti-EGFR therapies include the presence of redundant tyrosine kinase receptors, increased angiogenesis, and the constitutive activation of downstream mediators. Two recent landmark publications have also shown that specific mutations in the kinase domain of EGFR in some lung carcinomas are associated with markedly improved response rates to an EGFR tyrosine kinase inhibitor. Mutations in the EGFR receptor seem to play a significant role in determining the sensitivity of tumor cells to EGFR inhibitor therapy by altering the conformation and activity of the receptor. As the field of molecular therapeutics continues to evolve, a comprehensive understanding of resistance mechanisms will ultimately lead to refinements in our regimens to provide better care for patients with cancer.  相似文献   
188.
189.
Specialized DNA arrays for the differentiation of pancreatic tumors.   总被引:3,自引:0,他引:3  
PURPOSE: Malignant tumors of the pancreas are frequently indistinguishable from inflammatory tumors arising in the context of a chronic pancreatitis with the use of conventional imaging techniques. Thus, cytologic analysis of cells obtained by abdominal ultrasound, computed tomography, or endoscopic ultrasound-guided fine needle aspiration biopsy is required for diagnosis. However, the reliability of cytologic analyses of pancreatic fine needle aspirates remains unsatisfactory, with a diagnostic accuracy of < or =80%. The purpose of the current study was therefore to develop a novel diagnostic approach based on expression profiling of biopsy material using a specialized diagnostic cDNA array. EXPERIMENTAL DESIGN: Previous gene expression profiling studies were reevaluated to design a 558-feature diagnostic array. Minimal amounts of residual material from pancreatic cytology samples as well as surgically resected tumor and control tissue specimens were analyzed using the diagnostic array and a newly developed statistical classification system. RESULTS AND CONCLUSIONS: Our diagnostic approach resulted in 95% accurate differentiation between ductal adenocarcinomas and nonmalignant tumors of the pancreas. The diagnostic array, in conjunction with conventional diagnostic procedures, is thus suitable to significantly improve the reliability of pancreatic cancer diagnostics and can be expected to become a valuable new tool in the routine workup of suspect masses in the pancreas.  相似文献   
190.
PURPOSE: The stability of meropenem in i.v. solutions stored in polyvinyl chloride (PVC) bags and an elastomeric infusion device at concentrations commonly used in home care was studied. METHODS: Vials of meropenem were reconstituted with sterile water for injection and mixed with 0.9% sodium chloride injection (NS) to yield concentrations of 4, 10, and 20 mg/mL. Six replicate solutions were prepared in PVC containers and six in the Homepump ECLIPSE elastomeric infusion device. All solutions were stored at an average temperature of 5 degrees C and sampled immediately after preparation and at intervals up to 120 hours (five days); the 4-mg/mL solution was also sampled at 144 and 168 hours (seven days). Samples were assayed for meropenem concentration by stability-indicating high-performance liquid chromatography. RESULTS: All solutions of meropenem retained over 90% of the initial drug concentration at five days. The 4-mg/mL solutions retained over 93% of the initial concentration at seven days. The rate of meropenem decay did not differ significantly between PVC and elastomeric infusion containers for the 4- and 20-mg/mL solutions; however, there was a difference for the 10-mg/mL solutions. CONCLUSION: Meropenem 4 mg/mL in NS was stable for at least seven days in PVC bags and elastomeric infusion containers when stored at 5 degrees C, and meropenem 10 and 20 mg/mL in NS was stable for at least five days in both containers at 5 degrees C.  相似文献   
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