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71.
Angiotensin converting enzyme (ACE) inhibition is a common therapeutic modality in the treatment of autosomal recessive polycystic kidney disease (ARPKD). This study was designed to investigate whether chronic inhibition of ACE would have a therapeutic effect in attenuating the progression of renal cystogenesis in an orthologous rat model of ARPKD, the polycystic kidney (PCK) rat. Lisinopril (3 mg/kg per day) was administered orally for a period of 12 weeks, beginning at post-natal week 4. Lisinopril treatment resulted in an ∼30% improvement in the collecting duct cystic indices (CT CI) of PCK animals. Activation of extracellular signal-regulated kinase 1 (ERK1) and 2 (ERK2), proliferative signaling markers, and proliferating cell nuclear antigen (PCNA), an end-point marker for proliferation, was reduced following chronic treatment with lisinopril compared to that in vehicle-treated PCK rats. To assess whether apoptotic pathways were altered due to chronic ACE inhibition, we examined p38 mitogen activated protein kinase (MAPK) and stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), which are markers of apoptotic signaling cascades. p38 MAPK was significantly reduced (P < 0.0001) following chronic treatment with lisinopril, but no change in the activation of SAPK/JNK could be detected by immunoblot analysis. Lisinopril treatment resulted in a significant reduction (P < 0.01) in cleaved caspase-7 levels, but not caspase-3 activity, in PCK rat kidneys compared to the vehicle-treated PCK rat kidneys. Proteinuria was completely ameliorated in the presence of chronic ACE inhibition in the lisinopril-treated rats compared with the vehicle-treated PCK rats. In all, these findings demonstrated that chronic ACE inhibition can beneficially alter proliferative and apoptotic pathways to promote therapeutic reductions in renal cyst development in ARPKD.  相似文献   
72.
Prostatic calculi are common and are associated with inflammation of the prostate. Recently,it has been suggested that this inflammation may be associated with prostate carcinogenesis. The aim of this study was to investigate the relationship between prostatic calculi and prostate cancer (PCa) in prostate biopsy specimens. We retrospectively analyzed 417 consecutive patients who underwent transrectal ultrasonography (TRUS) and prostate biopsies between January 2005 and January 2008. Based on the biopsy findings,patients were divided into benign prostatic hyperplasia and PCa groups. TRUS was used to detect prostatic calculi and to measure prostate volume.The correlations between PCa risk and age,serum total PSA levels,prostate volume,and prostatic calculi were analyzed. Patient age and PSA,as well as the frequency of prostatic calculi in the biopsy specimens,differed significantly between both the groups (P〈0.05). In the PCa group,the Gleason scores (GSs) were higher in patients with prostatic calculi than in patients without prostatic calculi (P = 0.023). Using multivariate logistic regression analysis,we found that patient age,serum total PSA and prostate volume were risk factors for PCa (P = 0.001),but that the presence of prostatic calculi was not associated with an increased risk of PCa (P = 0.13). In conclusion,although the presence of prostatic calculi was not shown to be a risk factor for PCa,prostatic calculi were more common in patients with PCa and were associated with a higher GS among these men.  相似文献   
73.
K+ -Cl- cotransporter (KCC) plays an important role in maintaining neuronal activity. However, the effect of seizure activity or pharmacological manipulation of GABAergic transmission on KCC expression remains to be clarified. Therefore, the present study was performed to investigate whether seizure activity or GABA receptor agonist treatment changes KCC expression in the gerbil hippocampus. Furthermore, the effect of blockade of KCC on inhibitory transmission in the dentate gyrus was identified following applications of GABA receptor agonists. The distribution of KCC immunoreactivity in the hippocampus was similarly detected between seizure-resistant (SR) and seizure-sensitive (SS) gerbils. Baclofen (a GABAB receptor agonist) treatment markedly increased KCC expression in the gerbil hippocampus. Baclofen treatment significantly reduced paired-pulse inhibition in the dentate gyrus. Furosemide (a KCC inhibitor) treatment amplified the effect of baclofen on paired-pulse responses. In contrast, muscimol (a GABAA receptor agonist) treatment reduced KCC expression. Enhanced paired-pulse inhibition by muscimol treatment was not affected by furosemide treatment. These findings suggest that seizure activity in the gerbil may not affect KCC expression in the hippocampus. In addition, altered KCC immunoreactivity induced by baclofen or muscimol may play an important role in maintaining or regulating inhibitory transmission during GABA receptor activation.  相似文献   
74.
The purpose of the present paper was to determine error-monitoring ability and its relationship with executive function in patients with schizophrenia. In order to evaluate error-monitoring ability, the error negativity (Ne) and error positivity (Pe) were measured using the Stroop task. The correct-related negativity (CRN) and positivity (Pc) were also measured. In addition, neuropsychological tests were administered in order to evaluate executive function. The patients with schizophrenia had significantly reduced Ne and augmented CRN amplitudes, but the Pe and Pc amplitudes of the patients were comparable to those of the controls. In addition, the Ne amplitude, measured at Fcz was positively correlated with the Trail Making Test (TMT), part B response time, and the categories achieved on the Wisconsin Card Sorting Test (WCST) in patients with schizophrenia. No significant correlations were found between Ne amplitude and performance on the neuropsychological tests in the controls. And no associations were detected between CRN, Pe, Pc amplitudes and neuropsychological performance, in either the patients with schizophrenia or the controls. Reduced Ne amplitudes and augmented CRN amplitudes in patients with schizophrenia suggest the dysfunctional behavior-monitoring system in these patients. The functional significances of Ne and Pe are discussed.  相似文献   
75.
The authors evaluated the relationships between preoperative and postoperative kinematics in 50 osteoarthritic knees scheduled for cruciate retaining total knee arthroplasty with regards to posterior femoral roll back and external femoral rotation using a navigation system from 10° to 120° of knee flexion. Although posterior femoral roll back was maintained, external femoral rotation was significantly decreased compared to those of the preoperative knee after total knee arthroplasty. However, the amount of posterior roll back and external femoral rotation after total knee arthroplasty were found to be significantly positively related to those measured preoperatively (r = 0.62 and 0.57, respectively). These significant kinematic correlations may explain why preoperative range of knee motion influences range of motion after total knee arthroplasty.  相似文献   
76.

Background

This study was undertaken to investigate the trends of orthopedic publications during the last decade, and to document the country of origin, journal, funding source, and language of contribution using PubMed.

Methods

Orthopedic articles published between 2000 and 2009 were retrieved from PubMed using the following search terms: "orthopaedic[Affiliation] AND ("2000/1/1"[PDAT]: "2009/12/31"[PDAT])" and "orthopedic[Affiliation] AND ("2000/1/1"[PDAT]: "2009/12/31"[PDAT])." The articles were downloaded in XML file format, which contained the following information: article title, author names, journal names, publication dates, article types, languages, authors'' affiliations and funding sources. These information was extracted, sorted, and rearranged using the database''s management software. We investigated the annual number of published orthopedic articles worldwide and the annual rate of increase. Furthermore, the country of publication origin, journal, funding source, and language of contribution were also investigated.

Results

A total of 46,322 orthopedic articles were published and registered in PubMed in the last 10 years. The worldwide number of published orthopedic articles increased from 2,889 in 2000 to 6,909 in 2009, showing an annual increase of 384.6 articles, or an annualized compound rate of 10.2%. The United States ranked highest in the number of published orthopedic articles, followed by Japan, the United Kingdom, Germany, and the Republic of Korea. Among the orthopedic articles published worldwide during the last 10 years, 37.9% pertained studies performed in the United States. Fifty-seven point three percent (57.3%) of articles were published in journals established in the United States. Among the published orthopaedic articles, 4,747 articles (10.2%) disclosed financial support by research funds, of which 4,688 (98.8%) articles utilized research funds from the United States. Most articles were published in English (97.2%, 45,030 articles).

Conclusions

The number of published orthopedic articles has been increasing over the last decade. The number of orthopedic articles, journals publication, and funding sources were dominated by research conducted in the United States, while share and growth of Asian countries including Japan, the Republic of Korea, and China were notable.  相似文献   
77.
PURPOSE: The purpose of this work was to describe the radiologic findings of pulmonary tuberculosis in patients who presented with acute respiratory failure. METHODS: We included patients who had newly diagnosed active pulmonary tuberculosis and who presented with acute respiratory failure. Initial chest radiographic (n = 17) and high-resolution CT (n = 11) findings of each patient were analyzed retrospectively. RESULTS: Of 1,010 patients with active pulmonary tuberculosis, 17 patients (1.7%) presented with acute respiratory failure. Nine (53%) of the 17 patients died. The most common initial chest radiographic findings were small nodular lesions (16/17; 94%), consolidation (13/17; 76%), and ground-glass opacity (12/17; 70%). Eleven (69%) of 16 nodular lesions, 9 of 13 (69%) consolidations, and 10 of 12 (83%) ground-glass opacities were bilateral. On HRCT (n = 11), miliary micronodular lesions were seen in 6 patients (55%), whereas bronchogenic spread of tuberculosis with disseminated centrilobular nodules and tree-in-bud appearance was seen in 5 patients (45%). Diffuse areas of ground-glass attenuation were seen in all six patients with miliary nodules and four of five patients with bronchogenic spread of tuberculosis. CONCLUSION: Patients with pulmonary tuberculosis occasionally present with acute respiratory failure. In this condition, chest radiograph most commonly shows bilateral small nodular lesions mixed with consolidation or ground-glass opacity, whereas HRCT demonstrates findings of miliary or bronchogenic disseminated tuberculosis with diffuse areas of ground-glass attenuation.  相似文献   
78.
J Y Ahn  S O Kwon  J Y Joo 《Neurologia medico-chirurgica》2001,41(12):603-5; discussion 606
A 50-year-old male presented with an extremely rare dorsal wall aneurysm of the internal carotid artery manifesting as intracerebral hemorrhage. Computed tomography demonstrated intracerebral hemorrhage on the frontal base. Magnetic resonance imaging clearly showed the hemorrhage was related to an aneurysm of the internal carotid artery. Cerebral angiography disclosed an elongated aneurysm of the dorsal wall of the internal carotid artery. The aneurysm was packed as fully as possible with Guglielmi detachable coils to achieve complete obliteration. The patient was discharged without neurological deficits. Dorsal internal carotid artery aneurysms have a high risk of premature rupture due to their unusual shape and position, adhesion to the brain tissue, and fragile neck. Direct clipping requires careful brain retraction, necessary exposure of the aneurysm, and gentle neck manipulation. Endovascular treatment is an alternative method for obliteration of the aneurysmal sac.  相似文献   
79.
AIM: In the elderly with renal disease, the clinical presentations are frequently inconsistent with the pathologic findings. We tried to clarify the differences in pathological findings between the young and the elderly, in Korea and in Western countries, and the usefulness of a percutaneous renal biopsy in the elderly with renal disease. PATIENTS AND METHODS: We analyzed the clinical presentations and spectrums of renal histopathology by reviewing medical records and renal biopsy reports retrospectively in 117 Korean patients aged 60 years or more with renal disease. RESULTS: 85 patients had primary renal disease. The remaining 32 patients had renal diseases associated with systemic conditions. Out of the 85 patients with primary renal disease, 61 cases presented as idiopathic nephrotic syndrome. Compared with renal biopsy results of younger adult patients (age 15-59, n = 1,908), membranous nephropathy, crescentic glomerulonephritis, membranoproliferative glomerulonephritis, amyloidosis, light chain disease, and thrombotic thrombocytopenic purpura were more prevalent, but IgA nephropathy and lupus nephritis were less common in the elderly patients. In clinical presentation, nephrotic syndrome and rapidly progressive renal failure were more prevalent, but asymptomatic urinary abnormality was less common in elderly patients. The responsiveness to treatment was good in elderly patients with minimal-change lesion (complete remission in all patients) but poor in crescentic glomerulonephritis, IgA nephropathy, and membranoproliferative glomerulonephritis. From the above findings, the clinical presentation, patterns of histopathology and responsiveness to treatment of elderly Korean patients were similar to those of the younger Korean control group and the Western elderly group. CONCLUSION: Percutaneous renal biopsy is a useful diagnostic aid and can be used as a therapeutic guideline even in elderly patients with renal disease.  相似文献   
80.
It is not well known how the nonoperated contralateral hand behaves in bilateral carpal tunnel syndrome (CTS). The postoperative clinical course of the nonoperated contralateral hand in unilateral CTS is not well documented either. Of 324 CTS patients, the authors studied 37 who had carpal tunnel release on one hand only to evaluate the postoperative outcome of the nonoperated contralateral hand. The other 287 patients had operations on both hands. Seven patients were excluded because of missing data or because they could not be contacted. All 324 patients were subject to clinical and electrodiagnostic studies on both hands. The patients were divided into three groups. Group I was composed of patients who had bilateral CTS, diagnosed clinically and electrophysiologically, but who had surgery done only on the hand with the most pronounced symptoms. The patients in group II showed symptoms of CTS in one hand only. However, the opposite hand was diagnosed with subclinical CTS: Electrodiagnostic studies showed involvement of the median nerve, but without symptoms. Group III was composed of true unilateral CTS patients, diagnosed by symptoms and electrodiagnostic study. The results of the electrodiagnosis were categorized according to the severity of median nerve damage (mild, moderate, severe). The outcome and postoperative clinical course of the nonoperated contralateral hand were evaluated by electromyography and telephone survey. This method of survey was used because of the vast spread of patients throughout the country. Within 1 year, all 30 operated hands showed significant improvement, 20 of which belonged to group I. Regarding progress of the nonoperated contralateral hand, 10 patients showed improvement of one grade whereas 5 patients showed three grades of improvement. In another 5 patients there was no change whatsoever. In addition, from groups II and III there were 5 patients who showed no change in the nonoperated hand. The postoperative electromyographic findings of the nonoperated contralateral hand was not commensurate with the symptoms. However, regardless of electromyographic results, the nonoperated contralateral hand showed significant improvement (p < 0.0001). Patients with unilateral CTS did not experience any symptom development in the nonoperated contralateral hand.  相似文献   
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