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Electrostatic effects play an important role in protein interactions and may alter the biodistribution of antibodies. To study the effect of molecular charge on the biodistribution and infection imaging properties of human polyclonal immunoglobulin G (IgG), its iso electric point was varied by changing the level of diethylene triamine penta-acetic acid (DTPA) substitution: 0.8, 0.9, 3.7, 5.1 and 5.9 DTPA/IgG. Biodistributions of the different IgG preparations were determined at 10 min, 1, 6, 24, and 48 h post injection in normal rats, and infection imaging properties were determined in rats withEscherichia coli thigh infections. The biodistribution was significantly affected by pl. The immunoglobulin preparations with 0.9 and 3.7 DTPA/IgG showed faster clearance from the circulation and generally lower accumulation in most organs. The images had a target-to-background ratio of approximately 1.3–2.3:1. These results suggest that even though targeting is not affected by the level of DTPA substitutions, preparations with 0.9 and 3.7 DTPA/IgG may be superior imaging agents because of reduced accumulation by background organs.  相似文献   
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Medical records of 158 patients with bipolar depression were analysed for the incidence of a switch from depression to maniform states (mania and hypomania). Relation to psychopharmacological treatment was investigated. Thirty-nine (25%) patients of the total sample had switched to a maniform state during the treatment period in the hospital. Among that group the phenomenon occurred in 23 patients (15%) as a hypomania and in 16 patients (10%) as a mania. Patients with a switch were significantly more often treated with tricyclic antidepressants (TCA) than patients without switch (79.5% vs 51.3%). Mood stabilising medication might reduce the risk for switching, especially in patients treated with TCA; however, it seems not totally sufficient, since 59% of the switched patients received mood stabilisers. The switch phenomenon was not associated with sociodemographic or clinical data. Received: 23 September 1998 / Accepted: 28 September 1998  相似文献   
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The number of aeromedical transport services accepting pediatric patients (ATSP) in the United States has increased greatly over the past decade. Most aeromedical transport services are primarily designed for adults but will also transport children. Suggested guidelines for ATSP were published by the American Academy of Pediatrics (AAP) in 1986. This survey of 65 ATSP and their abidance by the major AAP guidelines showed that two thirds of the ATSP were based at facilities with pediatric tertiary care capabilities; most ATSP were not directed by pediatric critical care (PCC) or pediatric emergency care (PEC) specialists; most transport team personnel were not trained in PCC or PEC; most ATSP had specific protocols for different clinical situations; most ATSP had separate equipment appropriate for pediatric patients; and there was little variation in transport team composition based on different clinical situations. In summary, all ATS surveyed transported children, but few were aware of the AAP guidelines, and only one in 65 was in complete abidance with the recommendations.  相似文献   
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Disseminated intravascular coagulation invariably accompanies placement of peritoneovenous (LeVeen) shunts, which suggests that ascitic fluid contains procoagulant material capable of activating blood coagulation. In this study, we identified thrombogenic activity in human ascites and the hemostatic pathway by which it acts. Peritoneal fluid was removed percutaneously from patients with ascites due to various causes. Four fractions were prepared by centrifugation: cells, a low-speed, cell-free fluid, a high-speed supernatant, and the precipitate from the high-speed centrifugation. Cellular fractions from all ascitic fluids shortened a one-stage clotting time of normal pooled plasma by 68% in comparison with saline solution and endotoxin controls. Similarly, the cell-free fluids also shortened the clotting time of normal pooled plasma by 41%. The cellular and cell-free fractions shortened the clotting time of factor VIII-deficient plasma but failed to demonstrate procoagulant activity in factor VII-deficient plasma. These fractions had no effect on platelet aggregation or the platelet release reaction. The high-speed precipitate was dissociated by ethylenediaminetetra-acetate (EDTA) into fluid phase and precipitate, both of which demonstrated procoagulant activity. Furthermore, high-speed precipitate contained protein, phospholipid, and sterol in proportions similar to those of plasma membranes and contained membrane-bound vesicles as identified by means of electron microscopy. This material could be rendered inactive by heating to 100 degrees C for 2 minutes or by incubation with phospholipase C for 15 minutes. Finally, the ability of the high-speed precipitate to shorten the clotting time was prevented by preincubation with a monoclonal antibody, which is known to inhibit the procoagulant activity of human tissue factor. We suggest that several entities contribute to the procoagulant properties of human ascites, with procoagulant material deriving at least in part from peritoneal cells. The sedimentable procoagulant factor appears to be associated with cellular membranes or membrane fragments and is thromboplastin-like in its chemical composition, immunoreactivity, and substrate specificity.  相似文献   
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Teaching clinical research: what clinicians need to know   总被引:1,自引:0,他引:1  
Clinicians are well suited in many ways to conducting research, but appropriate training and support must be provided. A series of multidisciplinary workshops designed to facilitate clinical research are used as a focus for describing common problems and their solutions. Practical means for initiating and assisting clinical research are proposed.  相似文献   
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A 12-year-old girl developed a reversible myeloradiculopathy 1 week after a wasp sting. Delayed neurologic hypersensitivity reactions to Hymenopteran stings occur primarily in adults. Reactions involving both the peripheral and central nervous systems are extremely rare and have never been reported in a child. The mechanisms underlying this uncommon reaction may be related to age-dependent differences in immunologic responses.  相似文献   
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In 148 patients with impingement lesion type I or type II, we performed an arthroscopic subacromial decompression (ASD). 122 patients ran a follow up one to three years post-operatively. All patients were pre- and postoperatively documented by a 100 point shoulder score. The mean score was 57.9 (+/- 11.5) preoperatively. Postoperatively there was a significant increase to 80.7 (+/- 17.9) (p < 0.05). 15% of the patients with a postoperative score less than 70 points were determined as failures. Patients with a preoperative pain history of more than one year had a significantly worse result (79.1 +/- 8.4) compared to those patients with a preoperative course less than one year (88.8 +/- 11.6) (p < 0.05). Other significant factors were the patient's age, and calcific tendinitis, whereas sex, preoperative range of motion, muscle atrophy, and degeneration of the acromioclavicular joint did not significantly influence the result. Our results after ASD in patients with subacromial pathology without a rupture of the rotator cuff are encouraging. Therefore, ASD seems to be a reasonable alternative to open acromioplasty.  相似文献   
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