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991.
992.
Summary Quantitative cineventriculographic measurements (ventricular volumes, ejection fraction, and myocardial mass) were obtained in 15 neonates with pulmonary atresia and intact ventricular septum. There was a wide dimensional range for the right ventricle, from a reduced through normal to enlarged. A restrictive tricuspid valve (less than 12 mm) was associated with a small or diminutive right ventricle. A normal function of the right ventricle was present only in those cases with normal-sized chambers. The left ventricular end-diastolic volume was always greater than normal. The ejection fraction was normal only if a normal myocardial mass was present. Additional abnormalities were frequent in the myocardium of both ventricles, such as extreme thinning of the wall of the right ventricle and hypoplasia or fibroelastosis of the left ventricle. All these factors can lead to a poor surgical prognosis despite good anatomical correction.  相似文献   
993.
994.
BACKGROUND AND OBJECTIVES: Anticoagulant (AC) and antiplatelet (AP) drugs are effectively used in the prevention of thromboembolic events, with the trade-off of bleeding side effects, particularly intracranial. The aim of this study was to determine the incidence of intracranial bleeding in the population of Reggio Emilia and to investigate the potential effect of AC and AP drugs. DESIGN AND METHODS: We reviewed all the patients admitted for cerebral hemorrhages to our hospital between April 1998 and September 2000. Data were collected with a standardized form. All the patients were followed-up to estimate long-term mortality. Chi(2) and t-tests were used as appropriate. Logistic regression analysis was performed to test predictors of mortality. Pharmaceutical department data were employed to estimate the total number of patients receiving AC and AP drugs. RESULTS: We found 241 cases (107/134 female/male, mean age 61 years, 133/107 spontaneous/traumatic events, 0.32/1,000/year overall). Twenty-nine and 47 of these patients were being given AC or AP drugs, respectively (4.9/1,000/year and 3.7/1,000/year). The relative risk of intracranial bleeding was 11.5 in AP and 15.3 in AC treated patients. Two patients (one underwent neurosurgery and one thrombolytic treatment) were excluded from mortality and risk factors analysis. Six patients were lost from follow-up and excluded from mortality analysis. Overall mortality was 100/233 (42.9%); mortality in traumatic events was 25/103 (24.2%) versus 75/130 (57.7%) in spontaneous events. Mortality was 19/29 (65.5%), 26/47 (55.3%) and 55/157 (35%) in AC recipients, AP recipients, and untreated patients, respectively. This increased risk was mainly confined to traumatic events (p = 0.06), without difference between AC and AP recipients. At the time of the event, the mean duration of oral AC treatment was 26.3 months (range 1-120). Mean INR was = 3.1 (range 1.6-8.8). Mortality was significantly predicted by the Glasgow Coma Scale Score (GCS) at admission (p < 0.0001), by the type of bleeding (spontaneous versus traumatic) (p = 0.0026), and by age (p < 0.0001). INTERPRETATION AND CONCLUSIONS: Careful selection of patients and prevention of traumatic events are the main candidate mechanisms to reduce intracranial bleeding in patients being treated with AC and AP drugs.  相似文献   
995.
996.
Image-guided endoscopic transnasal removal of recurrent pituitary adenomas   总被引:35,自引:0,他引:35  
Lasio G  Ferroli P  Felisati G  Broggi G 《Neurosurgery》2002,51(1):132-6; discussion 136-7
OBJECTIVE: To assess the role that neuronavigation plays in assisting endoscopic transsphenoidal reoperations for recurrent pituitary adenomas. METHODS: During a 45-month period, 19 endoscopic endonasal transsphenoidal reoperations were performed for recurrent pituitary adenomas. In 11 of 19 patients, the procedure was performed with the aid of an optically guided system. Clinical records were reviewed retrospectively, with attention to the following: comparison of baseline clinical data, the duration of surgery, and the postoperative course and complications of both image-guided and non-image-guided endoscopic reoperations. In addition, to test the reliability of the neuronavigation system, we made measurements of intraoperative accuracy in five additional transnasal endoscopic procedures in "virgin" noses and sphenoidal sinuses. RESULTS: In both groups studied, we found no difference with regard to either morbidity or mortality, which were null. The mean setup time was 13 minutes shorter in non-image-guided procedures (P = 0.021), and the operative time was 36 minutes shorter in image-guided procedures (P = 0.038). No other statistically significant differences were found between the two groups. In all cases, we found that the system performed without malfunction. Continuous information regarding instrument location and trajectory was provided to the surgeon. Measurements of the intraoperative accuracy in the axial, coronal, and sagittal planes indicated a mean intraoperatively verified system error of 1.6 +/- 0.6 mm. CONCLUSION: Neuronavigation can be applied during endonasal transsphenoidal endoscopic surgery and requires a minimal amount of time. It makes reoperation easier, faster, and probably safer.  相似文献   
997.
In a survey carried out on 229 subjects who had undergone an augmentative mammaplasty it was possible to verify a postoperative increase in weight in 25 cases, four of which were clearly anorexic. We hypothesized that a change in perception of one's body proportions after the insertion of implants, might have been a determinant in blocking the mechanism leading to anorexia, or at least in the continuation of the recovering process. The aim of this article is obviously not to state that augmentative mammaplasty can be a kind of therapy for anorexia. Instead, we want to underline how a more pleasant contour of some body areas can have a role in solving deeper psychological problems.  相似文献   
998.
Background: The authors evaluated the relationship between leptin and the clinical, anthropometric and metabolic variables connected to the metabolic syndrome in obese individuals. Methods: A large group of patients with different degrees of obesity was investigated: body mass index (BMI) values, serum leptin, fasting glucose and insulin, triglycerides and HDL-cholesterol concentrations, insulin resistance index and blood pressure were measured. Results: On multiple regression analysis, serum leptin levels appeared to be positively correlated to the BMI and to the serum HDL-cholesterol concentration. Principal component factor analysis revealed three factors, explaining 61.3% of the total variance of the sample. General features of these factors were: factor 1 - BMI values and serum leptin and fasting glucose concentration; factor 2 - systolic and diastolic blood pressure and serum triglycerides and HDL-cholesterol concentration; factor 3 - fasting serum insulin concentration and insulin resistance index. Conclusions: In obese subjects multiple factors underlie the metabolic syndrome and therefore more than one mechanism may account for the clustering characteristics. In obese patients leptin loads only one factor, and therefore leptin does not appear to be a key feature in the metabolic syndrome. On the contrary, multiple correlation and factor analysis data give rise to the hypothesis that in obese patients, leptin may play a protective role against cardiovascular risk.  相似文献   
999.
PURPOSE: To investigate the ocular pharmacodynamic profile of a polymer nanoparticle system loaded with sodium ibuprofen (IBU-RS) in comparison to an aqueous solution of ibuprofen lysinate (IBL) in the rabbit eye both being applied topically. METHODS: Ocular inflammation was elicited by topical application of sodium arachidonate. Inflammation was quantified according to a modified Draize test. The protein level and the number of polymorphonuclear leukocytes in the aqueous humor were assessed after 2 h from arachidonate instillation. The ibuprofen concentration in the aqueous humor was evaluated by HPLC assay. The physico-chemical properties of nanoparticles were also evaluated. RESULTS: The IBU-RS nanosuspension formulation significantly reduced the primary signs of ocular inflammation as well as significantly reducing the protein level and the number of polymorphonuclear leukocytes in the aqueous humor compared with the IBL formulation. Furthermore, the aqueous humor drug concentration from the group treated with IBU-RS was significantly higher compared to the IBL-treated group. The IBU-RS nanosuspensions showed very interesting size and surface charge values, adequate for ophthalmic administration. CONCLUSIONS: The pharmacological profile of the topical IBU-RS nanosuspension formulation described in this study indicates that the dispersion of the drug within RS polymer nanoparticles increased its ocular bioavailability and ultimately its pharmacological activity.  相似文献   
1000.
PURPOSE: To evaluate the intraobserver reproducibility of a software designed to assess retinal blood flow with the Heidelberg Retina Flowmeter (HRF). METHODS: Ten subjects were consecutively recruited, and one eye of each patient was randomly selected for study. Blood flow measurements were analyzed by using an automatic full field perfusion image analysis (AFFPIA) program, which calculates the Doppler frequency shift and hemodynamic variables (flow, volume, and velocity) for each pixel. The resulting perfusion image is processed with respect to underexposed and overexposed pixels, saccades, and retinal vessel tree. Intraobserver reproducibility was calculated for the AFFPIA program. All the optic nerve heads were horizontally divided into three sections (superior, central, and inferior). The retinal blood flow was calculated in the superior and inferior section, and each section was further divided into three areas (temporal, nasal, and rim). The blood flow was evaluated for each area. RESULTS: When the same observer analyzed the same image five times (intraobserver intraimage reproducibility), the AFFPIA coefficient of variation ranged from 0.5% to 5% in the temporal area, from 0.1% to 5.3% in the nasal area, and from 0.5 to 28% in the rim area.When the same observer analyzed three different images of the same section once (intraobserver interimage reproducibility), the AFFPIA coefficient of variation of flow measurements ranged from 1% to 7.3% in the temporal area, from 1.5% to 10% in the nasal area, and from 2 to 30% in the rim area. CONCLUSION: Retinal blood flow measured by HRF and analyzed by AFFPIA had good intraobserver reproducibility. The reproducibility was significantly better in the temporal and nasal areas than in the rim area.  相似文献   
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