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991.
目的探讨螺旋CT多期增强扫描在胆囊癌诊断中的作用。方法对23例经病理证实的胆囊癌患者的多期螺旋CT表现进行回顾性分析。结果胆囊癌主要CT表现为胆囊壁的不规则增厚和结节状突起以及胆囊内的肿块,增强扫描强化明显且持续时间长。结论螺旋CT多期增强扫描在胆囊癌的定性诊断及了解胆囊癌的侵犯范围上具有重要作用。  相似文献   
992.
Molecular analysis of bacterial 16S rRNA genes has made a significant contribution to the identification and characterisation of bacterial flora in the human gut. In particular, this methodology has helped characterise bacterial families implicated in the aetiology of inflammatory bowel disease (IBD). In this study we have used a genus specific bacterial 16S PCR to investigate the prevalence and diversity of Pseudomonas species derived from the ileum of children with Crohn's disease (CD), and from control children with non-inflammatory bowel disease (non-IBD) undergoing their initial endoscopic examination. Fifty eight percent of CD patients (18/32) were positive using the Pseudomonas PCR, while significantly fewer children in the non-IBD group, 33% (12/36), were PCR positive for Pseudomonas (p<0.05, Fischer's exact test). Pseudomonas specific 16S PCR products from 13 CD and 12 non-IBD children were cloned and sequenced. Five hundred and eighty one sequences were generated and used for the comparative analysis of Pseudomonas diversity between CD and non-IBD patients. Pseudomonas species were less diverse in CD patients compared with non-IBD patients. In particular P.aeruginosa was only identified in non-IBD patients.  相似文献   
993.
The role of the cystic fibrosis transmembrane conductance regulator (CFTR) as a cAMP-dependent chloride channel on the apical membrane of epithelia is well established. However, the processes by which CFTR is regulated on the cell surface are not clear. Here we report the identification of a protein-protein interaction between CFTR and the cytoskeletal filamin proteins. Using proteomic approaches, we identified filamins as proteins that associate with the extreme CFTR N terminus. Furthermore, we identified a disease-causing missense mutation in CFTR, serine 13 to phenylalanine (S13F), which disrupted this interaction. In cells, filamins tethered plasma membrane CFTR to the underlying actin network. This interaction stabilized CFTR at the cell surface and regulated the plasma membrane dynamics and confinement of the channel. In the absence of filamin binding, CFTR was internalized from the cell surface, where it prematurely accumulated in lysosomes and was ultimately degraded. Our data demonstrate what we believe to be a previously unrecognized role for the CFTR N terminus in the regulation of the plasma membrane stability and metabolic stability of CFTR. In addition, we elucidate the molecular defect associated with the S13F mutation.  相似文献   
994.
We have developed an anion-exchange high-performance liquid chromatography (HPLC) method using Q Sepharose XL (Amersham Pharmacia Biotech) as adsorbent to analyze samples containing adenovirus. This method has several major advantages over the HPLC method previously described for quantitating particles, namely (1) a >10-fold improvement in the detection limit of adenovirus in crude preparations; (2) absence of interferences originating from nucleic acids and proteins which usually contaminate crude samples; (3) unprecedented sharpness and symmetry of adenovirus peak, rendering the identification of the viral peak unambiguous, even in extremely crude and dilute preparations; and (4) no enzymatic treatment required even for crude samples. This assay was used to quantitate particles in samples taken at the transfection and amplification stages of production of various recombinant adenovirus, and in cultures of wild-type adenovirus of different serotypes. A modification of this analytical method was also developed for the purification of infectious adenovirus particles, including fiber-modified and third-generation recombinant viruses, giving highly purified preparations from low-titer crude lysates with an excellent overall recovery (50-74%).  相似文献   
995.
The 9th International Workshop on Adverse Drug Reactions and Lipodystrophy in HIV provided a forum for the presentation of basic and clinical research focused on the pathogenesis and management of lipodystrophy and other adverse events associated with antiretroviral therapy. New data were reported on the contribution of both antiretroviral therapy and HIV infection itself on the development of metabolic abnormalities in patients with lipodystrophy, including insulin resistance and dyslipidaemia, which are associated with an increased risk of diabetes and cardiovascular disease. In addition, an emerging role of HIV and antiretroviral therapy in bone, liver and kidney disease were highlighted. A major focus of the data presented in these areas concerned the identification and evaluation of risk factors and appropriate surrogate markers for defining cardiovascular disease risk as well as other outcomes of long-term treatment. The complexity of defining such risk factors was underscored by data describing the impact of race, age and gender in the progression of metabolic disease and related complications among different HIV-infected populations. Finally, advances in the development of pharmacovigilance reporting systems in resource-limited settings and their impact upon healthcare policies and the provision of patient care were also described.  相似文献   
996.
Yeast strains isolated from the oropharynx of 87 consecutive patients infected with human immunodeficiency virus type 1 were examined for in vitro susceptibility to fluconazole. Candida albicans was isolated from 73 patients. Fifty-one patients had received antifungal therapy in the month preceding the yeast infection. Thirty-two patients had symptomatic oropharyngeal candidiasis. The MICs were correlated with azole use and with clinical symptoms and signs. Although there is overlap between groups, in vitro testing identified a large group of patients for whose yeast isolates the fluconazole MICs were high and who remained symptomatic while receiving azole therapy. This study supports the ability of in vitro testing to predict the clinical outcome of mucosal fungal infections. The study also demonstrates that azole resistance of oropharyngeal yeasts is a common problem in patients infected with human immunodeficiency virus type 1 and that this azole resistance has clinical relevance.  相似文献   
997.
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999.
OBJECTIVES: The objective was to examine the evidence to determine the optimal management of phantom limb pain in the preoperative and postoperative phase of amputations. METHODS: Trials were identified by a systematic search of MEDLINE, review articles, and references of relevant trials from the period 1966-1999, including only English-language articles. Included trials involved a control group, any intervention, and reported phantom pain as an outcome. RESULTS: Twelve trials were identified, including 375 patients whose follow-ups ranged in duration from 1 week to 2 years. Only three randomized, controlled studies with parallel groups and three randomized crossover trials were identified. Eight trials examined treatment of acute phantom pain, including epidural treatments (three trials), regional nerve blocks (three trials), treatment with calcitonin (one trial), and transcutaneous electrical nerve stimulation (one trial). Three trials demonstrated a positive impact of the intervention on phantom limb pain, but the remainder demonstrated no difference between the intervention and control groups. Four trials examined late postoperative interventions, including transcutaneous electrical nerve stimulation (two trials) and the use of Farabloc (a metal threaded sock) and ketamine (one trial each). With regard to late postoperative interventions, three of the four trials showed modest short-term reduction of phantom limb pain. There was no relation between the quality of the trial and a positive result of the intervention. CONCLUSIONS: Although up to 70% of patients have phantom limb pain after amputation, there is little evidence from randomized trials to guide clinicians with treatment. Evidence on preemptive epidurals, early regional nerve blocks, and mechanical vibratory stimulation provides inconsistent support for these treatments. There is currently a gap between research and practice in the area of phantom limb pain.  相似文献   
1000.
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