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991.
We report the case of a 51-year-old woman who underwent mitral valve replacement for prolapse with severe regurgitation, depressed ejection fraction, and atrial fibrillation. Two weeks post-operatively, a transesophageal echocardiogram was performed for bacteremia. The patient was found incidentally to have a large free-floating ball thrombus in the left atrium. The patient was managed with anticoagulation because of the high-risk nature of repeat surgery. One month following diagnosis, the patient still had persistent thrombus in the left atrium seen on transthoracic echocardiography despite therapeutic anticoagulation. Free-floating ball thrombus is a rare and dramatic finding seen on echocardiography in patients with mitral valve disease.  相似文献   
992.
Infliximab, a monoclonal antibody against tumor necrosis factor-alpha, has been shown to be effective for the treatment of refractory Crohn's disease in adult patients, but experience in pediatrics is limited. This retrospective study included 88 children and adolescents, 39 girls and 49 boys, with a median age of 14 years (range 3.3-17.9). Infliximab was indicated for active disease (66%) and/or fistulas (42%) that were refractory to corticosteroids (70%), and/or other immunosuppressive (82%) agents, and/or parenteral nutrition (20%). Patients received 1 to 17 infusions (median 4) of 5 mg/kg (range 3.8-7.3) of infliximab during a median time period of 4 months (1-17 months). Infusion reaction was noted in 13 patients (15%), with a total of 16 reactions in 450 infusions (4%). At Day 90 after the first infusion of infliximab, symptoms improved in 49% of patients, whereas 29% of patients were in remission and 13% of patients relapsed. From Day 0 to Day 90, Harvey-Bradshaw score decreased from 7.5 to 2.8 (P < 0.001), C-reactive protein from 36 to 16 mg/L (P < 0.01), and 1-hour erythrocyte sedimentation rate from 35 to 17 mm (P < 0.01). Dosage of corticosteroids decreased from to 0.59 to 0.17 mg/kg/d (P < 0.001); 53% of patients could be weaned of corticosteroids and 92% of parenteral nutrition. Treatment with infliximab is well tolerated and effective in most children and adolescents with Crohn's disease that is refractory to conventional immunosuppressive therapy. Nevertheless, long-term efficacy remains to be shown, and further studies are urgently needed to precisely determine the best modality of continuing treatment.  相似文献   
993.
In primary cultures of rat pituitary cells and in a pituitary sommatolactotroph cell line (GH4C1), endogenous core-clock- as well as hormone-genes such as prolactin displayed a rhythmic expression pattern, fitted by a sinusoidal equation in which the period value was close to the circadian one. This is consistent with the presence of a functional circadian oscillator in pituitary cells whose importance was ascertained in GH4C1 cell lines stably expressing a dominant negative mutant of BMAL1. In these cells, both endogenous core-clock- and prolactin-genes no more displayed a circadian pattern. Some genes we recently identified as mouse pituitary BMAL1-regulated genes in a DNA-microarray study, lost their circadian pattern in these cells, suggesting that BMAL1 controlled these genes locally in the pituitary. The intra-pituitary circadian oscillator could then play a role in the physiology of the gland that would not be seen anymore as a structure only driven by hypothalamic rhythmic control.  相似文献   
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996.

Objective

To assess the construct validity of the Cochin Hand Function Scale (CHFS) and the relevance of using aggregate scores for the scleroderma Health Assessment Questionnaire (sHAQ) and Medical Outcomes Study 36‐Item Short Form Health Survey (SF‐36) in systemic sclerosis (SSc).

Methods

We evaluated 50 patients with SSc (mean ± SD age and disease duration 54 ± 12 years and 9 ± 8 years, respectively), of which 26 had limited cutaneous SSc (lcSSc) and 23 diffuse SSc (dSSc). Quality of life was assessed by the SF‐36, global disability by the Health Assessment Questionnaire (HAQ) and sHAQ, and hand disability by the CHFS. Construct validity was assessed by convergent and divergent validity (Spearman's rank correlation coefficient) and factor analysis.

Results

The CHFS had good construct validity and its total score explained 75% of the variance of the HAQ. The HAQ had better construct validity than the aggregate sHAQ and their scores correlated well (r = 0.88). The aggregate sHAQ was no better than the HAQ in discriminating between lcSSc and dSSc. SF‐36 physical and mental components had acceptable convergent and divergent validity. Factor analysis of the 8 subscales extracted 3 factors explaining 72% of the variance, which differed from the a priori stratification with physical and mental subscales extracted in the same factor.

Conclusion

In patients with SSc, the CHFS has good construct validity, the HAQ should be preferred over the aggregate sHAQ for assessing physical functioning, and use of SF‐36 physical and mental components aggregate scores is questionable.  相似文献   
997.
Patent foramen ovale is a frequent remnant of the fetal circulation. Affecting approximately 25% of the adult population. Its recognition, evaluation and treatment has attracted increasing interest as the importance and frequency of its implication in several pathologic processes, including ischemic stroke secondary to paradoxic embolism, the platypnea-orthodeoxia syndrome, decompression sickness (DCS) (an occupational hazard for underwater divers and high altitude aviators and astronauts) and migraine headache, has become better understood. Echocardiographic techniques have emerged as the principle means for diagnosis and assessment of PFO, in particular contrast echocardiography and transcranial Doppler. Its treatment remains controversial with a general tendency to propose a percutaneous closure among the symptomatic patients.  相似文献   
998.
Aortic stenosis is the most common valvular heart disease in the Western world and its prevalence is increasing with an aging population. Although medical therapy has little to offer in terms of prognosis or symptomatic relief, at least one-third of patients with severe aortic stenosis are denied valve surgery as a result of age and comorbidities. This review describes the development of the percutaneous aortic valve as an alternative therapy for such patients. The technique, initial results and the current limitations of the procedure are explained alongside the ongoing trials necessary in order that such therapy may eventually be made widely available.  相似文献   
999.
Although it is often functional at presentation, acute renal failure has a poor prognosis in patients with cirrhosis. The role of inflammation, a key event in the outcome of cirrhosis, has never been studied in this setting. We aimed to investigate the predictive factors of mortality in patients with cirrhosis and acute functional renal failure, specifically in relation to inflammatory events. One hundred consecutive patients with cirrhosis from 5 French hospitals were prospectively included at the day of onset of acute renal failure. Medical history, treatments, and procedures during the month before inclusion were recorded. Physical examination, blood and urinary chemistries, and renal ultrasound examination were performed. The presence of systemic inflammatory response syndrome (SIRS), infection, and sepsis was assessed. The primary outcome was in-hospital mortality. The mechanism of renal failure was functional in 83 patients. Causes of renal failure were hypovolemia (34%), hepatorenal syndrome without ongoing infection (17%), hepatorenal syndrome with ongoing infection (16%), nephrotoxicity (2%), and multifactorial (31%). SIRS was observed in 41% of patients, 56% of them with infection. In-hospital mortality was 68% in patients with SIRS and 33% in patients without (P = 0.001). In multivariate analysis, only model for end-stage liver disease score and presence of SIRS, but not infection, remained associated with a poor outcome. Conclusion: The presence of SIRS, with or without infection, is a major independent prognostic factor in patients with cirrhosis and acute functional renal failure. This suggests that preventing and treating SIRS could decrease mortality in patients with cirrhosis and acute renal failure.  相似文献   
1000.
BACKGROUND: Solvent/detergent (S/D) inactivates enveloped viruses in plasma. The current technology requires a plasma fractionation facility and is applied to large plasma pools, which increases the cost and risks of exposure to S/D-resistant pathogens and lowers the content of protein S and alpha2-antiplasmin. Two S/D treatment procedures for single donations or minipools of plasma have been developed with a single-use bag system. STUDY DESIGN AND METHODS: Frozen plasma samples were thawed and treated in disposable bags with either 2 percent tri(n-butyl)phosphate (TnBP) at 37 degrees C or 1 percent TnBP and 1 percent Triton X-45 at 31 degrees C for 4 hours. Plasma samples were extracted three times with 7.5 percent sterile castor oil to remove TnBP and Triton X-45. The TnBP-treated plasma samples were further subjected to a clarifying centrifugation (3800 x g, 30 min). Final plasma samples were dispensed into individual bags and frozen at -30 degrees C. Plasma quality was assessed at each step of the procedures. RESULTS: Both processes yielded greater than 90 percent mean recovery of coagulation factors (clottable fibrinogen, von Willebrand factor, and factors VIII, V, VII, IX, X, and XI), anticoagulants (protein C, protein S), protease inhibitors (antithrombin, alpha2-antiplasmin), total protein, albumin, and immunoglobulins. Global coagulation tests of the treated plasma samples were normal. Final TnBP and Triton X-45 content was less than 10 and 50 ppm, respectively. CONCLUSION: S/D treatment of plasma can be performed in a closed-bag system under conditions that maintain plasma protein quality. The technology is simple, presents advantages over the industrial large-scale S/D plasma process, and could be performed in blood centers.  相似文献   
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