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1.
The purpose of this study was to determine if changes in hindlimb motoneuron membrane electrical properties occur 4–6 months after spinal transection in the adult animal. Eight acute and nine chronic animals were spinalized at T12. Intracellular recordings from motoneurons innervating the triceps surae were performed. Membrane electrical properties, including resting potential, action potential peak amplitude, afterhyperpolarization duration, rheobasic current, input resistance and axonal conduction velocity were measured. There were no statistical differences found between group means or frequency distributions in the membrane properties of motoneurons assessed from acute and chronic spinal animals. Thus, alteration of motoneuron membrane properties does not appear to be a major contributing factor to the hyperexcitable hindlimb reflex activity demonstrated by chronic spinal animals. 相似文献
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Lucinda G. Carr Yiling Xu Wei-Hsien Ho Howard J. Edenberg 《Alcoholism, clinical and experimental research》1989,13(4):594-596
All nine exons of the ADH2(3) allele, which encodes the human alcohol dehydrogenase beta 3 subunit, have been cloned and sequenced. Comparison of this sequence to the ADH2(1) nucleotide sequence revealed only a single difference that results in an amino acid change, thus proving that the significant kinetic differences between these two isozymes is due to the Cys for Arg substitution at position 369. There are also two silent polymorphisms, and two changes in noncoding regions. 相似文献
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Michelle Lucinda DeOliveira M.D. Tarcisio Triviño M.D. Ph.D. Gaspar de Jesus Lopes Filho M.D. Ph.D. 《Journal of gastrointestinal surgery》2006,10(8):1140-1143
Carcinoma of the papilla of Vater is classified as periampullary cancer representing 5% of all gastrointestinal tract malignancies.
Early and accurate diagnosis is important for those patients with a tumor of the papilla, as the prognosis is more favorable
than in other periampullary neoplasms. Endoscopically obtained biopsies from suspicious papillae can detect an early tumor,
although even for skilled pathologists it is often difficult to differentiate carcinomas from noninvasive lesions on the basis
of forceps biopsies. The purpose of this study was to assess the preoperative diagnostic accuracy of duodenoscopy appearance
and biopsy in all cases with suspicion of tumor. Thirty patients with suspicion of carcinoma of the papilla of Vater and with
final diagnosis established by pancreatoduodenectomy were included in this retrospective study. In each case, a comparison
was made between endoscopic biopsy and duodenoscopic appearance. Duodenoscopic appearance sensitivity and accuracy for malignancy
were 86% and 83%, respectively, whereas endoscopic biopsy sensitivity and accuracy were 65% and 67%, respectively. Although
preoperative diagnosis of carcinoma of the papilla of Vater is useful for making therapeutic decisions, the diagnostic value
of the endoscopic appearance was superior to endoscopic biopsy in this series.
Presented at the 2003 American Hepato-Pancreato-Biliary Association Congress, Miami, Florida, February 27-March 3, 2003.
Supported by FADA-CAPES/PROP 200J (M.L.D.). 相似文献
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The burden of illness associated with psoriasis: cost of treatment with systemic therapy and phototherapy in the US 总被引:2,自引:0,他引:2
Crown WH Bresnahan BW Orsini LS Kennedy S Leonardi C 《Current medical research and opinion》2004,20(12):1929-1936
OBJECTIVE: To evaluate utilization and direct healthcare expenditures among psoriasis patients treated with systemic therapy and phototherapy in the United States. DESIGN: Cohort study using retrospective administrative medical claims. PATIENTS: Psoriasis patients treated with systemic therapy and phototherapy, as well as a matched cohort of non-psoriasis patients. All patients were covered by employer-sponsored insurance between 1 April 1996 and 31 December 2000. MAIN OUTCOME MEASURES: Estimated risk of hospitalization and total annual healthcare expenditures overall and by comorbidity status were compared for persons with psoriasis using systemic therapy or phototherapy and persons without psoriasis. Annualized utilization rates for hospitalizations, and use of emergency department, outpatient physician, outpatient laboratory, and outpatient pharmaceutical services were also compared across the two cohorts. RESULTS: Seventeen percent of psoriasis patients were treated with systemic therapy or phototherapy. Patients with comorbid anemia, carcinoma, diabetes, depression, GI disorders, hepatotoxicity, hypertension, and nephrotoxicity had significantly higher expenditures than non-psoriasis patients with the same comorbidities (p < or =0.05). Elevated risk of hospitalization also contributed to higher expenditures in patients treated with systemic therapy or phototherapy. Limitations of this study include those inherent in using claims data such as dependence on diagnosis coding, the fact that psoriasis severity cannot be determined directly from claims data, confounding comorbidities, and the fact that only direct healthcare expenditures were considered in this analysis. CONCLUSION: Psoriasis patients treated with systemic therapies/phototherapies have significantly more comorbidities and higher mean total healthcare expenditures compared to non-psoriasis patients. Psoriasis patients with selected comorbidities have significantly higher mean total healthcare expenditures compared to non-psoriasis persons with the same comorbidities. 相似文献
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Lucinda M. Hilliard Amanda K. Sampson Russell D. Brown Kate M. Denton 《Current hypertension reports》2013,15(1):71-79
Sex differences exist in the regulation of arterial pressure and renal function by the renin-angiotensin system (RAS). This may in part stem from a differential balance in the pressor and depressor arms of the RAS. In males, the ACE/AngII/AT1R pathways are enhanced, whereas, in females, the balance is shifted towards the ACE2/Ang(1-7)/MasR and AT2R pathways. Evidence clearly demonstrates that premenopausal women, as compared to aged-matched men, are protected from renal and cardiovascular disease, and this differential balance of the RAS between the sexes likely contributes. With aging, this cardiovascular protection in women is lost and this may be related to loss of estrogen postmenopause but the possible contribution of other sex hormones needs to be further examined. Restoration of these RAS depressor pathways in older women, or up-regulation of these in males, represents a therapeutic target that is worth pursuing. 相似文献
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