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81.
We report the case of OTM who presented with dynamic aphasia following a stroke that occurred in the left basal ganglia. He showed drastically reduced spontaneous speech in the context of well preserved naming, repetition and comprehension skills. OTM was particularly impaired in generating words, sentences and phrases when cued by a stimulus allowing many response options. By contrast, when a single response was strongly suggested by a stimulus, he could generate verbal responses adequately. OTM's non-verbal response generation abilities varied across tasks. He performed in the normal range in a motor movement generation test and he produced as many figures as controls when tested on a figural fluency task. He showed, however, many perseverations on this test. Moreover in a random number generation task he produced more responses that were part of ascending and descending series of numbers. The patient's impairments are interpreted as a consequence of two deficits. The first of these consists of an inability to generate verbal responses particularly in situations of high competition and involves the function of left frontal regions. The second deficit is one of impaired novel thought generation as evidenced by perseverations. This second deficit has been proposed to be a function of basal ganglia damage.  相似文献   
82.
BACKGROUND: Nitric oxide (NO), a potent vasodilator produced by endothelial cells, is reduced in patients with peripheral arterial disease (PAD), but the mechanism has not been fully elucidated. Because NO is rapidly inactivated by superoxide anion, we speculated that enhanced oxidative stress could lower NO generation. The aim of our study was to investigate if an imbalance between oxidative stress and NO does exist in patients with PAD and if an increase of NO formation could be achieved by an antioxidant treatment. METHODS: In a first study, serum levels of nitrite and nitrate (NOx), markers of NO generation, and 8-hydroxy-2-deoxyguanosine (8-OHdG), a marker of oxidative stress and maximal walking distance (MWD), were measured in 40 PAD patients and 40 controls. In a second study, 10 PAD patients were randomly allocated in a crossover design to intravenous propionyl-L-carnitine (6 g/day) or placebo for 7 days, with a washout of 30 days between the two phases of the trial. Serum levels of NOx and 8-OHdG were measured before and after the study. RESULTS: Compared with controls, serum levels of 8-OHdG (mean +/- SD) were significantly increased in PAD patients (4.4 +/- 3.1 ng/mL vs 2.4 +/- 1.2 ng/mL; P < .001), and serum levels of NOx were significantly decreased (11.6 +/- 6 microM vs 17 +/- 6.1 microM; P < .001). Levels of 8-OHdG and NOx were inversely correlated (r = -0.879; P < .001). Serum levels 8-OHdG were inversely correlated with MWD (r = -0.48, P = .002). The interventional trial showed no changes in the patients given placebo. Patients treated with propionyl-L-carnitine showed a significant increase of MWD from 101 +/- 31 meters to 129 +/- 35 meters (P = .007) and in NOx from 14.5 +/- 4.5 microM to 17.1 +/- 3.8 microM (P = .007). A significant decrease of 8-OHdG from 3.6 +/- 1.1 ng/mL to 2.6 +/- 1 ng/mL was also found (P = .005.) CONCLUSIONS: This study suggests that in PAD patients, the reduction of NO generation could be dependent upon enhanced oxidative stress.  相似文献   
83.

Background

Self-expanding metallic stent (SEMS) placement is a valid form of therapy for patients with obstructing colon rectal cancer. The procedure is not feasible for a minority of patients with a very low risk of bowel perforation. This report analyzes the results of a technical detail used for SEMS placement.

Methods

In 43 patients with colon rectal obstruction, the SEMS apparatus was introduced through a guidewire passed above the obstruction in the channel of a pediatric nasogastroscope (diameter, 4.9 mm). The pediatric nasogastroscope was passed into the obstruction and above, allowing the anatomy of the colorectal lesion and the passage of the guidewire to be visualized directly.

Results

The SEMS was inserted successfully in all cases without complications. In a previous series of 82 patients who had passage of the guidewire through the obstruction blindly, four technical failures occurred (nonsignificant difference).

Conclusions

A pediatric nasogastroscope can be useful for passing the colon rectal obstruction and guiding the passage of the guidewire under direct vision.  相似文献   
84.
Patients with systemic sclerosis (SSc) are at a high risk of the development of ischaemic digital ulcers (DUs) that can be complicated with infections, gangrene, and osteomyelitis. The aim of this study is to evaluate the role of endostatin in scleroderma DUs.In total, 90 SSc patients were enrolled in this study. Serum endostatin levels and DU assessment were determined in all SSc patients. The serum levels of endostatin significantly increased with progression of capillaroscopic damage (P < .01). The serum levels of endostatin are significantly (P < .05) higher in SSc patients with new DUs than in SSc patients without new DUs (127 ± 31.1 ng/mL vs 116.3 ± 39.7 ng/mL). The Receiver Operating Characteristic (ROC) curves demonstrated good accuracy of new DU prediction for the serum level of endostatin (0.70, P < .01 [95% confidence interval (CI) 0.59‐0.81]). Using a cut‐off value of 116 ng/mL, the odds ratio was 2.609 (CI 1.075‐6.330, P < .05). The serum levels of endostatin are significantly (P < .01) higher in SSc patients with infected DUs than in SSc patients without infected DUs (139.2 [114.6‐340.91] ng/mL vs 117.5 [64.3‐163.9] ng/mL). Serum levels of endostatin are higher in patients with DUs, especially in those with infected DUs.  相似文献   
85.
86.
Study ObjectiveTo investigate whether diabetes, hypertension (HTN), and obesity can be considered risk factors for endometrial polyps (EPs) independently of age and menopausal status.DesignRetrospective analysis (Canadian Task Force classification III).SettingDepartment of Obstetrics and Gynecology of the University of Foggia, Italy.PatientsA total of 353 Caucasian women undergoing office hysteroscopy to assess abnormal uterine bleeding, infertility, cervical polyps, and abnormal sonographic patterns.InterventionsDemographic characteristics and data on diabetes, HTN, and menopausal status were collected and anthropometric parameters were analyzed. Vaginoscopic hysteroscopy was performed with a 5-mm continuous-flow operative office hysteroscope. When present, EPs were treated during the same procedure by means of 5-Fr scissors or electrode.Measurements and Main ResultsIn 134 (38%) of 353 cases, EPs were found. Univariable and multivariable analysis were performed to verify the presence of a statistically significant association among age, menopause, HTN, obesity, diabetes (independent variables), and the presence of EPs. Univariable logistic analysis showed a statistically significant association among age, menopause, HTN, obesity, and the presence of EPs. However, when multivariable logistic regression was performed, all the independent variables, except age, lost statistical significance (OR 1.05, 95% CI 1.02–1.07, p <.001).ConclusionAlthough it appears that EP is a disorder of aging, the significance of diabetes, HTN, and obesity, as well as menopause, on the development of EPs should be reconsidered.  相似文献   
87.
Thirty-three patients with II type mixed essential cryoglobulinemia (MEC) were randomized into two groups: one to receive combined therapy including prednisone plus interferon, the other to receive prednisone therapy. Interferon was administered as induction treatment (3 Mu/day) and then as maintenance therapy (3 Mu three times a week). 83% of the combined therapy patients responded as opposed to 27% of the prednisone treated patients. Among the patients that responded to combined therapy, nine of them had a complete response, four a partial response, and two a minor response. None of the patients treated with prednisone therapy responded completely but only two had a partial and two a minor response. Four patients (three of combined therapy and one of prednisone therapy) showed proteinuria before the treatment which improved at the end of the induction therapy. Ten patients showed anti-HCV positivity which remained unchanged after the treatment. Three patients showed liver involvement secondary to cryoglobulinemia and an improvement of histological pattern after the induction with combined therapy. One patient showed an improvement of peripheral neuropathy after induction with the combined therapy. These data suggest the effectiveness of interferon given as induction and as maintenance treatment in the therapy of II type mixed essential cryoglobulinemia.  相似文献   
88.
89.
The interaction of phosphatidylserine (PS), exposed on the surface of apoptotic cells and with its specific receptor (PtdSerR) expressed by microglia, is a crucial event in the recognition and clearance of apoptotic neurons. Here, we extend our previous studies in which PS-liposomes mimicking apoptotic cells were used to investigate the functional role of PS-PtdSerR interactions on microglial functional state. Purified rat microglial cells were either incubated with PC12 cells maintained in complete medium (healthy), exposed to staurosporine or serum deprivation (apoptotic), or treated with hydrogen peroxide (necrotic). After 24 hours, supernatants from co-cultures and single cell type cultures were analyzed for nitric oxide (NO), tumor necrosis factor-alpha (TNF-alpha), interleukin-10 (IL-10), prostaglandin E2 (PGE2), transforming growth factor-beta1 (TGF-beta1), and nerve growth factor (NGF). When lipopolysaccharide (LPS)-activated microglia was cultured with apoptotic PC12 cells, NO and TNF-alpha levels significantly decreased, IL-10 was not affected, and PGE2 levels were substantially increased. In addition, TGF-beta and NGF syntheses increased when resting microglia was cultured with apoptotic but not healthy or necrotic PC12 cells. We proposed that upon interaction with PS-expressing apoptotic neurons, microglia no longer act as a promoter of the inflammatory cascade and that the specific microglial functional state induced by PS-PtdSerR may be relevant for the final outcome of neurodegenerative diseases.  相似文献   
90.
OBJECTIVE: We studied the hemostatic effects of tranexamic acid in patients undergoing elective surgery involving the thoracic aorta. METHODS: In a double-blind, randomized fashion, 60 consecutive patients were assigned to two treatment groups: 30 patients (placebo group) received infusion of saline solution, and 30 (treatment group) received tranexamic acid (1 g before skin incision, an infusion of 400 mg/h during the operation, and 500 mg in the pump priming). Perioperative bleeding was considered as a primary outcome. Perioperative allogeneic transfusions, major thrombotic complications (myocardial infarction, pulmonary embolism, renal insufficiency), and surgical outcomes were also considered. RESULTS: Patients treated with tranexamic acid showed significant reductions in postoperative bleeding, both in terms of the amount collected during the first 4 postoperative hours (median 307 mL, interquartile range 253-361 mL in the placebo group vs median 211 mL, interquartile range 108-252 mL in the treatment group, P =.002) and in terms of total bleeding (median 722 mL, interquartile range 574-952 mL in the placebo group vs median 411 mL, interquartile range 313-804 mL in the treatment group, P =.04). Consequently, the number of patients transfused differed significantly between groups (21 patients [72.4%] in the placebo group vs 13 [44.8%] in the treatment group, P =.033). Patients in the treatment group showed significant reductions in the total amount for the entire group of packed red cells transfused (13,500 mL in the treatment group vs 28,000 mL in the placebo group, P =.012) and in the total amount of allogeneic transfusions (23,400 mL in the treatment group vs 53,000 mL in the placebo group, P =.024). No differences in perioperative thrombotic complications were found. CONCLUSIONS: In this initial series of patients undergoing thoracic aortic surgery, tranexamic acid appeared effective in reducing perioperative bleeding, with a significant reduction in the need for allogeneic transfusions and without any increased risk of thrombotic complications.  相似文献   
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