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Existing clinical approaches and tools to measure burn tissue destruction are limited resulting in misdiagnosis of injury depth in over 40% of cases. Thus, our objective in this study was to characterize the ability of short‐wave infrared (SWIR) imaging to detect moisture levels as a surrogate for tissue viability with resolution to differentiate between burns of various depths. To accomplish our aim, we constructed an imaging system consisting of a broad‐band Tungsten light source; 1,200‐, 1,650‐, 1,940‐, and 2,250‐nm wavelength filters; and a specialized SWIR camera. We initially used agar slabs to provide a baseline spectrum for SWIR light imaging and demonstrated the differential absorbance at the multiple wavelengths, with 1,940 nm being the highest absorbed wavelength. These spectral bands were then demonstrated to detect levels of moisture in inorganic and in vivo mice models. The multiwavelength SWIR imaging approach was used to diagnose depth of burns using an in vivo porcine burn model. Healthy and injured skin regions were imaged 72 hours after short (20 seconds) and long (60 seconds) burn application, and biopsies were extracted from those regions for histologic analysis. Burn depth analysis based on collagen coagulation histology confirmed the formation of superficial and deep burns. SWIR multispectral reflectance imaging showed enhanced intensity levels in long burned regions, which correlated with histology and distinguished between superficial and deep burns. This SWIR imaging method represents a novel, real‐time method to objectively distinguishing superficial from deep burns.  相似文献   
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Objective Our studies aimed to evaluate in clinical trials the safety and immunogenicity of an H5 live influenza vaccine candidate obtained using classical reassortment techniques from a low pathogenicity avian influenza (LPAI) A/Duck/Potsdam/1402‐6/86(H5N2) virus and the cold‐adapted (ca) donor strain A/Leningrad/134/17/57(H2N2). Methods During Phase I–II clinical trials, volunteers received intranasally two doses of reassortant influenza vaccine strain A/17/Duck/Potsdam/86/92 (H5N2) 21 days apart. Clinical examination of all vaccinees was conducted 7 days post‐vaccination. Serum antibody responses were measured by hemagglutination‐inhibition and microneutralization and local antibodies were estimated using an enzyme‐linked immunosorbent assay test. Results The vaccine was safe and of low reactogenicity with no febrile reactions. After revaccination 47·1–54·8% of subjects showed ≥fourfold seroconversions of Hamagglutination inhibition (HAI) antibodies to the hemagglutinin (HA) antigen of the A/17/Duck/Potsdam/86/92 (H5N2) virus and 29·4–30·8% were seroconverted to the HA antigen of the reverse genetics reassortant A/Indonesia/05/2005 × PR8 IBCDC‐RG (H5N1). Virus‐neutralizing antibody levels in sera of volunteers were similar to those shown in HAI test. The virus‐specific nasal IgA antibody response after two vaccine doses demonstrated significant increases of ≥fourfold rise SIgA antibodies (65%) geometrical mean titers (16·0) and a rise in SIgA antibodies (2·8) compared with one dose. Conclusion The live attenuated influenza vaccine candidate prepared using the LPAI A(H5N2) strain was well tolerated and elicited serum and local immune responses. There was evident cross‐reactivity to the A(H5N1) strain in the HAI test.  相似文献   
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Previously unknown derivatives of the diterpenoid isosteviol and the glycoside steviobioside containing onium nitrogen atoms were synthesized. The antimicrobial and antifungal activities of these compounds were studied.  相似文献   
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RATIONALE AND OBJECTIVES: This cooperative multicenter human study was designed to evaluate the safety, magnetic resonance (MR) imaging characteristics, and clinical response to a single gadolinium contrast agent: gadopentetate dimeglumine. MATERIAL AND METHODS: Ninety-five patients (age range: 1 month to 78 years; sex: 50 males, 45 females) were included in this prospective study. The patients presented clinically with a variety of cranial or spinal signs and symptoms for which an intrathecal contrast myelogram or cisternogram was requested by clinical staff. Via lumbar puncture (20-25 g needle), 3 to 5 mL/ml of cerebrospinal fluid were withdrawn and mixed with a single volume of 0.5 (n = 63), 0.7 (n = 13), 0.8 (n = 12), or 1.0 (n = 7) cc/mL of gadopentetate dimeglumine (Magnevist; Schering, Berlin, Germany). This was then injected into the subarachnoid space, and the needle was removed. Immediate and delayed (up to 96 hours) T1- and T2-weighted MR imaging was performed on super conductive, high-field (1.0-1.5 tesla) imaging units in two or three planes. All patients were hospitalized for an observation period of 24 hours following the procedure, and follow-up neurologic examinations were performed serially for 6 to 12 months afterward. RESULTS: No patient manifested gross behavioral changes, neurologic alterations, or seizure activity at any time following the procedure. Nineteen patients (20%) experienced postural postlumbar puncture headache, six patients had nausea (6%), and two patients had episodes of vomiting (2%), all which resolved within the first 24 hours of the lumbar puncture with conservative bed rest. CONCLUSION: This cooperative study demonstrates the general safety and feasibility of low dose (0.5-1.0 mL/ml) intrathecal gadopentetate dimeglumine administration. The potential useful clinical applications include the evaluation of obstructions and communications of the various subarachnoid spaces, spontaneous or traumatic/postsurgical craniospinal cerebrospinal fluid leaks, and subarachnoid space CSF flow and parenchymal CNS interstitial diffusion dynamics. This worldwide cooperative study seeks to progressively perform human studies for further definitive evaluation of the practical clinical applications, of the relationship of this technique to other imaging studies and modalities, and the long-term safety of the procedure in a larger number of subjects.  相似文献   
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Examinations and operations were performed in 32 children aged from 2 months to 15 years with common bile duct cysts. The extirpation of the cyst, hepaticojejunostomy were performed in 13 patients, cystoduodenostomy in 13, cystojejunostomy --in 4, external drainage--in 3 patients. The follow-up observations lasted for 1-10 years. Good results were obtained in most of the patients.  相似文献   
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To determine the minimally allowable levels of oxygen delivery and consumption in infants with acute severe thermal injury, the authors studied the oxygen transport system in 36 patients aged 1 year and 2 months to 3 years who had burns of more than 15%, but less than 50% of the body surface in February 2001 to January 2004. The findings indicate that in infants, the acute period of thermal injury is characterized by oxygen debts despite the hyperdynamic circulatory regimen. By calculating the coefficients of paired correlation and deriving the linear regression of oxygen uptake with other parameters of the oxygen transport system, the authors estimated the minimum allowable levels of performance of the oxygen transport system: less than 623.2 ml/min/m2 for oxygen delivery, more than 190.0 ml/min/m2 for oxygen consumption with the cardiac index of greater than 4.31 l/min/m2.  相似文献   
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