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1.
Purpose: Spray-freeze drying (SFD) is a recently applied method to develop pharmaceutical powders. This study aimed to analyze the competence of Trehalose, Mannitol, Lactose, and Sorbitol instability and aerosolization of Immunoglobulin G (IgG) via SFD.

Methods: Induced soluble aggregates were quantified at 0 and 3?months, and 45?°C using size-exclusion chromatography. Conformation and thermogravimetric assessments were done by Fourier transform infrared spectroscopy and differential scanning calorimetry. Laser light scattering was performed to determine the particle sizes. Aerodynamic features were characterized by twin stage impinger and scanning electron microscopy.

Results: Although sugars/polyols preferably stabilized IgG following the process, storage stabilization was achieved in Trehalose, Trehalose-Lactose, Lactose, and Trehalose-Mannitol-based powders with soluble aggregates <5%. The conformation of antibody was preserved with β sheet content from 66.28% to 76.37%. Particle sizes ranged from 5.23 to 8.12?µm. Mannitol exhibited the best aerodynamic behavior, fine particle fraction (FPF: 70%) but high degree of protein aggregation during storage.

Conclusions: SFD could favorably stabilize antibody using Trehalose and its combination with Lactose and Mannitol, and also, Lactose alone. Sorbitol disturbed IgG powder recovery. Incorporation of other types of excipient is required for efficient respiratory delivery of IgG molecules.  相似文献   

2.
Journal of Gastroenterology - Sarcopenia (severe muscle depletion) is a prevalent muscle abnormality in patients with cirrhosis that confers poor prognosis both pre- and post-liver transplantation....  相似文献   
3.
Attenuation correction (AC) for myocardial perfusion SPECT (MPS) had not been evaluated separately in women despite specific considerations in this group because of breast photon attenuation. We aimed to evaluate the performance of AC in women by using automated quantitative analysis of MPS to avoid any bias. METHODS: Consecutive female patients--134 with a low likelihood (LLk) of coronary artery disease (CAD) and 114 with coronary angiography performed within less than 3 mo of MPS--who were referred for rest-stress electrocardiography-gated 99mTc-sestamibi MPS with AC were considered. Imaging data were evaluated for contour quality control. An additional 50 LLk studies in women were used to create equivalent normal limits for studies with AC and with no correction (NC). An experienced technologist unaware of the angiography and other results performed the contour quality control. All other processing was performed in a fully automated manner. Quantitative analysis was performed with the Cedars-Sinai myocardial perfusion analysis package. All automated segmental analyses were performed with the 17-segment, 5-point American Heart Association model. Summed stress scores (SSS) of > or =3 were considered abnormal. RESULTS: CAD (> or =70% stenosis) was present in 69 of 114 patients (60%). The normalcy rates were 93% for both NC and AC studies. The SSS for patients with CAD and without CAD for NC versus AC were 10.0 +/- 9.0 (mean +/- SD) versus 10.2 +/- 8.5 and 1.6 +/- 2.3 versus 1.8 +/- 2.5, respectively; P was not significant (NS) for all comparisons of NC versus AC. The SSS for LLk patients for NC versus AC were 0.51 +/- 1.0 versus 0.6 +/- 1.1, respectively; P was NS. The specificity for both NC and AC was 73%. The sensitivities for NC and AC were 80% and 81%, respectively, and the accuracies for NC and AC were 77% and 78%, respectively; P was NS for both comparisons. CONCLUSION: There are no significant diagnostic differences between automated quantitative MPS analyses performed in studies processed with and without AC in women.  相似文献   
4.
Among many conventional techniques, nuclear techniques have shown to be faster, more reliable, and more effective in detecting explosives. In the present work, neutrons from a 5 Ci Am-Be neutron source being in water tank are captured by elements of soil and landmine (TNT), namely (14)N, H, C, and O. The prompt capture gamma-ray spectrum taken by a NaI (Tl) scintillation detector indicates the characteristic photo peaks of the elements in soil and landmine. In the high-energy region of the gamma-ray spectrum, besides 10.829 MeV of (15)N, single escape (SE) and double escape (DE) peaks are unmistakable photo peaks, which make the detection of concealed explosive possible. The soil has the property of moderating neutrons as well as diffusing the thermal neutron flux. Among many elements in soil, silicon is more abundant and (29)Si emits 10.607 MeV prompt capture gamma-ray, which makes 10.829 MeV detection difficult. The Monte Carlo simulation was used to adjust source-target-detector distances and soil moisture content to yield the best result. Therefore, we applied MCNP4C for configuration very close to reality of a hidden landmine in soil.  相似文献   
5.
H Meierkord  B Will  D Fish  S Shorvon 《Neurology》1991,41(10):1643-1646
A total of 110 patients underwent diagnostic evaluation for attacks of uncertain origin by means of video-EEG telemetry and had a diagnosis of pseudoseizures confirmed. Eighty-six patients (78%) were female, mean age of onset 25 years, and mean duration of attacks was 3 years. Many of the patients had erroneously been thought to be suffering from epilepsy. The attacks could be divided into two broad categories: attacks of collapse (one-third) and attacks with prominent motor activity (two-thirds). In some patients, the attacks were associated with incontinence and injury. The differential diagnosis and clinical features of the attacks are described. Additional psychiatric features were present in 52 (47%) patients. Follow-up (for a median 5 years; range, 1 to 14 years) showed that 40% of these patients stopped having pseudoseizures. This favorable outcome was associated with being female, leading an independent life, a formal psychological approach to therapy and counseling, and the absence of coexisting epilepsy, but not with the duration of pseudoepilepsy, prior episodes of pseudostatus, the coexistence of overt psychiatric disease, or the clinical features of the attacks.  相似文献   
6.
PURPOSE: To evaluate qualitative wall motion assessment vs. quantitative wall thickening for the assessment of subtle changes in myocardial systolic function using cine MRI. METHODS: Cine MR images were obtained in 5 canines with a significant coronary artery stenosis and in 2 controls on a 1.5T scanner. Qualitative results were obtained using a numerical scoring system; quantitative analysis was performed using a semi-automatic segmentation program. The techniques were matched and compared using Spearman correlations. RESULTS: All correlations in the experimental group revealed significant but weak to moderate relationships between the qualitative and quantitative results (e.g., at-risk tissue rho = 0.363, p < 0.0001; remote tissue rho = 0.275, p = 0.0002), with each identifying changes in regional function that ensued following creation of the stenosis. Intra-observer variability was reasonable in both methods when repeat analysis on a subset of the data was performed, with both techniques showing a significant correlation between the repeated measurements (quantitative - rho = 0.52, p < 0.0001; qualitative - rho = 0.54, p < 0.0001). CONCLUSION: Both methods were able to detect very limited wall motion abnormalities present in the canines with significant stenosis and either method gives comparable results.  相似文献   
7.
8.
PURPOSE: Although venous air embolism is a well recognized complication within most surgical subspecialties, it has only been reported recently during eye surgery in one adult, and never before in a child. We describe the case of a 17-month-old boy who sustained a possible air embolism during repair of an open trauma of his right eye. CLINICAL FEATURES: A vitrectomy through the pars plana with air-fluid exchange of the posterior chamber was performed under general anesthesia to remove a foreign body which had impaled the optic nerve. A few minutes after removal of the foreign body, a notable decrease in end-tidal CO(2), oxygen saturation and arterial blood pressure occurred, requiring administration of a high inspired oxygen fraction and vasopressors. Venous air embolism was strongly suspected after other causes of a decrease of end-tidal CO(2) and hypoxemia had been excluded. An arterial blood gas confirmed hypoxemia and respiratory acidosis. CONCLUSION: Although venous air embolism is a rare complication of eye surgery, it should nevertheless be considered as a possible complication during air-fluid exchange vitrectomy in children.  相似文献   
9.
The major purposes of this study were to provide normative data on articulation rate in preschool children and to examine the influence on articulation rate of age, gender, context, and utterance length. The subjects were twenty 3-year-old children and twenty 5-year-old children, equally balanced for gender. Durational measures of utterances were analyzed in syllables and phones per second in both spontaneous and imitated speech contexts. The articulation rate of the 5-year-old subjects was significantly faster than that of the 3-year-olds. Spontaneous speech was significantly faster and more variable than imitated speech. Some gender differences were found. Measures in syllables per second and phones per second, although not always yielding identical results, were found to be highly correlated.  相似文献   
10.
Summary Partial anomalous pulmonary venous connections (PAPVCs) are rare in association with an intact atrial septum. However, the diagnosis should be considered in patients with otherwise unexplained findings of left-to-right shunt and right heart enlargement. An unusual variant is presented, which we considered unsuitable for operative repair, based on findings at catheterization. Developmental, hemodynamic, and surgical considerations are discussed.  相似文献   
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