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991.
Branch pulmonary artery obstruction is one of the prime reasons for re-operation in patients who have undergone repair for tetralogy of Fallot. Branch pulmonary artery obstruction may develop over a period of time due to dilation of right ventricular outflow tract or it may be caused by residual stenosis after inadequate repair. This may lead to differential lung perfusion causing morbidity. Intra-operative capnogram monitoring reveals ventilation-perfusion relationship. We report two cases where the capnogram helped the diagnosis and management of branch pulmonary artery obstruction. We found a redundant patch in the first and an extra length of the homograft in second case which led to the obstruction. However, but for the changes in the intraoperative capnogram, this condition may by far remain undiagnosed considering the fact that it does not produce hemodynamic changes but can lead to postoperative morbidity.  相似文献   
992.
This study evaluates the accuracy of augmenting initial intraprocedural computed tomography (CT) during radiofrequency ablation (RFA) of hepatic metastases with preprocedural positron emission tomography (PET) through a hardware-accelerated implementation of an automatic nonrigid PET–CT registration algorithm. The feasibility of augmenting intraprocedural CT with preprocedural PET to improve localization of CT-invisible but PET-positive tumors with images from actual RFA was explored. Preprocedural PET and intraprocedural CT images from 18 cases of hepatic RFA were included. All PET images in the study originated from a hybrid PET/CT scanner, and PET–CT registration was performed in two ways: (1) direct registration of preprocedural PET with intraprocedural CT and (2) indirect registration of preprocedural CT (i.e., the CT of hybrid PET/CT scan) with intraprocedural CT. A hardware-accelerated registration took approximately 2 min. Calculated registration errors were 7.0 and 8.4 mm for the direct and indirect methods, respectively. Overall, the direct registration was found to be statistically not distinct from that performed by a group of clinical experts. The accuracy, execution speed, and compactness of our implementation of nonrigid image registration suggest that existing PET can be overlaid on intraprocedural CT, promising a novel, technically feasible, and clinically viable approach for PET augmentation of CT guidance of RFA.  相似文献   
993.
Asymmetric overgrowth has many differential diagnoses with considerable overlap, posing a diagnostic dilemma. The presence of chylous ascites, though unreported, might be expected as a manifestation of overgrowth syndromes with lymphatic involvement. We present a patient with hemihypertrophy who presented with chylous ascites at birth.  相似文献   
994.
AIM: To investigate the role of preoperative biliary drainage (PBD) in the outcome of classical pancreaticodu odenectomy. METHODS: A 10-year retrospective data analysis was performed on patients (n = 48) undergoing pancreaticoduodenectomy from March 1994 to March 2004 in department of surgery at SMS medical college, Jaipur, India. Demographic variables, details of preoperative stenting, operative procedure and post operative complications were noted. RESULTS: Preoperative biliary drainage was performed in 21 patients (43.5%). The incidence of septic complications was significantly higher in patients with biliary stent placement (P < 0.05, 0 vs 4). This group of patients also had a significantly higher minor biliary leak rate. Mortality and hospital stay in each group was comparable. CONCLUSION: Within this study population the use of PBD by endoscopic stenting was associated with a high incidence of infective complications. These findings do not support the routine use of biliary stenting in patients prior to pancreatico-duodenectomy.  相似文献   
995.
Summary: Benzoyl peroxide is used as an oxidizing agent for the first time in the synthesis of conducting polypyrrole. Synthesis of polypyrrole is commonly performed by chemical oxidative polymerization using water‐soluble oxidizing agents. In this work, polypyrrole was prepared using organic solvent‐soluble benzoyl peroxide as an oxidizing agent in the presence of p‐toluenesulfonic acid (p‐TSA) and sodium lauryl sulfate (SLS) surfactant via the inverted‐emulsion‐polymerization technique. During polymerization, SLS is converted to dodecyl hydrogensulfate (DHS) and incorporated on to polypyrrole along with p‐TSA dopant, indicating SLS is acting as emulsifier as well as dopant. The influence of synthesis conditions such as the duration of the reaction, the temperature, the concentration of the reactants, etc., on the properties of polypyrrole was investigated to determine the optimum conditions for the synthesis of polypyrrole salt. Polypyrrole was obtained in a reaction time of 1 h with high yield (154 wt.‐% with respect to pyrrole used) and good conductivity (2 S · cm?1). The conductivity of polypyrrole‐salt was found to be nearly the same even after seven months of storage at ambient temperature (1.7 S · cm?1).

  相似文献   

996.
The physiological, biochemical, and proteomic changes in germinating rice seedlings were investigated under arsenic stress. A marked decrease in germination percentage, shoot, and root elongation as well as plant biomass was observed with arsenic treatments, as compared to control, whereas accumulation of arsenic and malondialdehyde (MDA) in seedlings were increased significantly with increasing arsenic concentration (both AsIII and AsV). The up-regulation of some antioxidant enzyme activities and the isozymes of superoxide dismutase (SOD, EC 1.15.1.1), ascorbate peroxidase (APX, EC 1.11.1.11), peroxidase (POD, EC 1.11.1.7), and glutathione reductase (GR, 1.6.4.2) substantiated that arsenic accumulation generated oxidative stress, which was more pronounced in As(III) treatment. We also studied the protective effect of reduced glutathione (GSH) and cysteine (Cys) to As(III)/As(V) stressed seedlings. Both GSH and Cys imparted enhanced tolerance to seedlings against arsenic stress. Seedlings growth improved while level of MDA declined significantly when GSH and Cys were supplemented to As(III)/As(V) treatments suggesting GSH and Cys-mediated protection against oxidative stress. The arsenic content was highest in roots of seedlings grown in As(III) in the presence of GSH/Cys. However, in case of As(V) plus GSH or Cys, the arsenic content in seedlings was highest in shoots. The results are suggestive of differential metabolism of As(III) and As(V) in rice.  相似文献   
997.
Sensory gating refers to the central nervous system's ability to filter sensory inputs, and can be measured by comparing the suppression of event-related brain potential (ERP) amplitudes in a paired auditory stimulus procedure. Poor gating scores in schizophrenia may be caused by abnormal responses to the first (S1), the second (S2) or both of the paired stimuli. However, since S1 and S2 responses may index separate psychological phenomenon, corresponding to the ability to “gate in” and “gate out” sensory stimuli respectively, the precise mechanism affected in schizophrenia remains unclear. To examine the extent to which saliency processing abnormalities may contribute to S1 response deficits, standard and rare (15% probability) paired stimuli were presented to 21 participants with schizophrenia and 22 healthy controls. P50 and N100 ERP amplitude as well as low, beta and gamma frequency power were measured to examine the time course and relative contributions of oscillatory activity affecting auditory processing in schizophrenia. In this study, schizophrenia patients exhibited less evoked beta 1 power (12–20 Hz) in response to salient stimuli at S1, and lower N100 amplitude in response to all S1 stimuli. No group differences were found in the low, beta 2 (20–30 Hz), or gamma frequency ranges. These findings suggest aberrant sensory processing during stages of stimulus evaluation and saliency detection in schizophrenia.  相似文献   
998.
999.
The study identifies sensitive and tolerant cultivars of Zea mays L. (cv. Azad kamal (AK) and Azad uttam (AU)) towards As(V) induced stress, based upon growth biochemical parameters and metal(loid) levels in a sand culture. As(V) (μgg?1 dw) accumulation was lower in cv. AK (31 ± 1 and 107 ± 30) than cv. AU (34.5 ± 3.3 and 132.6) in leaves and roots, respectively, which correlated with lower levels of malondialdehyde and H?O?. No definite trend of Mn, Cu, Zn, Fe, Ca, K and Na accumulation signifies that As(V) has little influence on their uptake. Total chlorophyll and protein levels increased in cv. AK and decreased in cv. AU at 7d. Higher levels of SOD and GR in cv. AK and conversely higher levels of APX, GPX and CAT in cv. AU could be a possible differential detoxification mechanism between the cultivars. The results indicate that cv. AK seems to be arsenate tolerant than cv. AU. We assure that the undertaken study does not involve humans or experimental animals and were conducted in accordance with national and institutional guidelines for the protection of human subjects and animal welfare.  相似文献   
1000.
Corticotropin releasing factor (CRF) is implicated in a variety of stress-related disorders such as depression and anxiety, and blocking CRF receptors is a putative strategy for treating such disorders. Using a well-studied animal model of panic, we tested the efficacy of JNJ19567470/CRA5626, a selective, non-peptidergic CRF type 1 receptor (CRF1) antagonist (3, 10 and 40 mg/kg intraperitoneal injection), in preventing the sodium lactate (NaLac)-induced panic-like behavioural and cardiovascular responses. Adult male rats with chronic reduction of GABA levels (by inhibition of GABA synthesis with l-allyglycine, a glutamic acid decarboxylase inhibitor) in the dorsomedial/perifornical hypothalamus are highly anxious and exhibit physiological and behavioural responses to intravenous NaLac infusions similar to patients with panic disorder. These 'panic-prone' rats pre-treated with vehicle injections displayed NaLac-induced increases in autonomic responses (i.e. tachycardia and hypertensive responses), anxiety-like behaviour in the social interaction test, and flight-like increases in locomotor activity. However, systemically injecting such panic-prone rats with the highest dose of CRF1 receptor antagonist prior to NaLac infusions blocked all NaLac-induced behaviour and cardiovascular responses. These data suggest that selective CRF1 receptor antagonists could be a novel target for developing anti-panic drugs that are as effective as benzodiazepines in acute treatment of a panic attack without the deleterious side-effects (e.g. sedation and cognitive impairment) associated with benzodiazepines.  相似文献   
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