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11.
Patients with cystic fibrosis commonly acquire chronic pulmonary infection with alginate-producing Pseudomonas aeruginosa. The infection remains localized at the mucosal surfaces of the airways. Using enzyme-linked immunosorbent assays immunoglobulin concentrations and titers of specific antibodies to purified P. aeruginosa alginate and to P. aeruginosa sonicated antigens were measured in tears, saliva, sputum and serum. CF patients had significantly higher concentrations of IgG, IgA and SIgA in serum and saliva than controls. They also had significantly higher levels of specific antibodies to alginate and sonicated antigen in secretions and serum. Local production of IgA, IgG and IgM antibodies to P. aeruginosa was demonstrated. Only a minor proportion of specific IgA antibodies were present as secretory IgA in tears, saliva and sputum. The ratio of alginate-specific SIgA to specific monomeric IgA in sputum was significantly lower than the similar ratio in saliva, whereas the same ratio for specific P. aeruginosa sonicate antigens was found in saliva and sputum.  相似文献   
12.
13.
本文建立了体液中右旋儿茶素的RP-HPLC测定方法。采用C_(18)键合相硅胶为填料的固相提取柱进行样品预处理,右旋儿茶素的提取回收率为79.8%.应用二极管阵列检测器对色谱峰纯度进行鉴定。该法精密度好,方法回收率近100%,日内、日间的变异系数为2.4~5.6%,血浓69.6~1160 ng/ml范围内呈线性关系,r=0.9993。家兔静注右旋儿茶素18mg/kg,其药代动力学过程符合二室模型,分布相半衰期为0.129 h,消除相半衰期为1.19h。  相似文献   
14.
Direct condensation of 2-deoxy-D-ribose (1) with mercaptans using the P4O10/H2O/Bu3N reagent in chloroform resulted in coupling at C-3 to give the anomeric mixtures of the corresponding pentopyranoses 2 and pentofuranoses 3. After acetylation with acetic anhydride in dry pyridine of these 3-alkylthio pentofuranoses, coupling with the nucleobases uracil, thymine, and cytosine in accordance with the Friedel-Crafts catalyzed silyl Hilbert-Johnson method yielded the acetylated D-erythro nucleosides 7 as anomeric mixtures, separable only by means of chromatography either before or after deprotection with ammonia. The nucleosides 8a-e were devoid of any activity against HSV-1 and HIV-1.  相似文献   
15.
Hodgkin's disease of the mediastinum presented as a sternal mass in two young adults. The original biopsy materials were incorrectly interpreted as eosinophilic granuloma of bone (histiocytosis X). A delayed diagnosis (15 months) resulted in the death of one patient, whereas the other patient, whose diagnosis was made in one week, had an excellent response to therapy.  相似文献   
16.
Total hepatic protein synthesis was measured in vivo with a flooding-dose technique, and the production of total secreted proteins, albumin, complement component C3, and seromucoid fraction was measured in perfused livers of septic rats that received one of three different solutions infused intravenously; Group 1 received 16.4% dextrose; Group 2 received Aminosyn (25% BCAA) in 10.6% dextrose, and Group 3 received Freamine HBC (45% BCAA) in 10.6% dextrose. All solutions were isocaloric, and the amino acid solutions were isonitrogenous. The solutions were administered for 18 or 48 hours after the induction of sepsis. There were no significant differences in mortality rates in the three treatment groups. The negative nitrogen balance seen in the dextrose-infused animals was reversed to the same degree by the two different amino acid solutions. There were no significant differences in hepatic protein synthesis rates in vivo between the three groups of rats. Synthesis rates of secreted proteins in perfused liver were similar in the different treatment groups in the 18-hour experiments, whereas in the 48-hour experiments, synthesis rates of total secreted proteins, C3, and the serumucoid fraction were higher in Group 1 than in Groups 2 and 3. The results suggest that administration of an amino acid solution improves nitrogen balance in sepsis, but that this effect is not caused by stimulated hepatic protein synthesis. The nitrogen-sparing effect during sepsis of a branched chain amino acid (BCAA)-enriched solution does not seem to be superior to that of a balanced amino acid solution.  相似文献   
17.
Renal tubular sodium and water handling determined by the lithium clearance technique, plasma concentrations of atrial natriuretic peptide (ANP), angiotensin II, aldosterone, arginine vasopressin (AVP), and urinary excretion of prostaglandin E2 (PGE2) were determined both during basal conditions and before and after intravenous sodium loading with a 2.5% sodium chloride solution in patients with polycystic kidney disease (PKD), ten with normal or slightly reduced kidney function (PKDN) and seven with moderately reduced kidney function (PKDR), and in 15 healthy controls. In PKDN tubular function was normal, whereas in PKDR both proximal and distal reabsorption of sodium and water were reduced. Angiotensin II and aldosterone were normal in both groups of patients. During basal conditions ANP was higher in PKDR than in PKDN. PGE2 was significantly higher in PKDR than in PKDN. For all patients significant correlations were found between GFR and both ANP (rho = -0.51, n = 17, P less than 0.05) and PGE2 (rho = -0.53, n = 17, P less than 0.05). It is concluded that renal sodium handling is normal in the early stages of PKD. With deterioration of kidney function both proximal and distal tubular reabsorption of sodium is reduced and the accompanying changes in ANP and PGE2 may be compensatory phenomena counteracting declining glomerular filtration rate.  相似文献   
18.
Ninety nine consecutive insulin dependent and 101 non-diabetic pregnant women were examined by ultrasonograph to assess early fetal growth. In 42 of the diabetic mothers and three of the non-diabetic mothers the scan showed early intrauterine growth delay. At 4-5 years of age all children available for study were evaluated by the Denver developmental screening test. Only 23 of the 34 children of diabetic mothers with early intrauterine growth delay had normal test scores compared with 46 of the 50 children of diabetic mothers with normal intrauterine growth. The children failed in personal-social development, gross motor development, and particularly in language and speech development. Children of diabetic mothers with normal early fetal growth had scores very similar to those of the children of non-diabetic mothers, of whom 76 of the 86 tested had normal scores. This study suggests that children with a history of growth delay in early diabetic pregnancy should be screened for possible developmental impairment.  相似文献   
19.
Carcinoma of the hepaticopancreatic ampullar region: role of US   总被引:3,自引:0,他引:3  
Hepaticopancreatic ampullar tumors are so called because they are located at the confluence of the bile duct, pancreatic duct, and duodenum. Jaundice is an early sign of the disease and often leads to early diagnosis and favorable prognosis compared with other tumors that occur in this area. Of eight patients who underwent ultrasound (US) in the past 5 years, six (75%) were found to have tumor. The sizes of the tumors ranged from 1.6 to 2 cm. An intraluminal, polypoid mass in the distal part of the common bile duct was seen in four patients. In the other two patients, a sharply delineated mass gave rise to abrupt termination of the distal duct. Improved US resolution, more experience with this modality, and accurate diagnosis of these tumors with US will contribute to improved detection and prompt treatment.  相似文献   
20.
We present the new computerized Human Brain Atlas (HBA) for anatomical and functional mapping studies of the human brain. The HBA is based on many high-resolution magnetic resonance images of normal subjects and provides continuous updating of the mean shape and position of anatomical structures of the human brain. The structures are transformable by linear and nonlinear global and local transformations applied anywhere in 3-D pictures to fit the anatomical structures of individual brains, which, by reformatting, are transformed into a high-resolution standard anatomical format. The power of the HBA to reduce anatomical variations was evaluated on a randomized selection of anatomical landmarks in brains of 27 young normal male volunteers who were different from those on whom the standard brain was selected. The HBA, even when based only on standard brain surface and central structures, reduced interindividual anatomical variance to the level of the variance in structure position between the right and left hemisphere in individual brains. © 1994 Wiley-Liss, Inc.  相似文献   
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