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Blood samples were collected in peripheral venous blood of seven lactating sows, when their piglets were suckling. In four of the experiments samples were also taken when the sows were fed a meal. Gastrin, insulin, somatostatin and VIP levels were measured by radioimmunoassay. Insulin levels increased by approximately 100% for about 10 min in response to suckling, in some experiments even before the suckling occurred, i.e. when the sows saw, heard and smelled their piglets. In four of the sows suckling caused a biphasic twofold increase in gastrin levels - one immediate peak which lasted for a few min and a second peak of longer duration (about 30-60 min), whereas gastrin levels remained unchanged in three animals. Somatostatin levels usually reflected gastrin levels in a reciprocal way. Thus, a biphasic decrease of somatostatin levels occurred in the high gastrin responders. In contrast, somatostatin levels increased in the experiments, in which gastrin levels did not change. Immediate and short-lasting (a few minutes long) increases of VIP levels were also induced by suckling. Large litters and long suckling periods appeared to be related to greater changes of the levels of all the peptides measured. Feeding influenced insulin, gastrin and somatostatin levels in the same way as did suckling from both a qualitative and a quantitative point of view. In contrast, VIP levels were not increased by feeding. The possible functional effects of the suckling-induced release of gastrointestinal hormones and possible mechanisms of their release are discussed.  相似文献   
3.
This double-blind immunotherapy trial in children, using a purified and standardized Cladosporium herbarum allergen preparation, has shown that children with mould asthma and/or rhinoconjunctivitis, responded to immunotherapy with a decrease in specific IgE and a significant increase in specific IgG. There was a marked increase in the ratio specific IgG/specific IgE as a result of active treatment. IgE-CRIE radiostaining patterns showed no pronounced changes after 10 months' active treatment and no "new sensitivities" could be detected in the studied patients. IgG-CRIE radiostaining, primarily directed towards the important allergens, was significantly increased in the active group and particularly towards Ag-12 (partially identical to a previously described major allergen in Cladosporium herbarum, Ag-54). Children treated with histamine placebo showed no change in antibody patterns during 10 months of treatment.  相似文献   
4.
S. Dreborg  R. Einarsson 《Allergy》1992,47(4):418-423
The content of major allergens in biologically standardized allergenic preparations of birch, mite (Der p) , cat, Alternaria (Alt a) and ragweed (Amb e) was determined. It was found fairly constant between species , i.e. varied within a factor of 2, with the exception of Alt a 1 in Alternaria alternata extract. This variation is allowed by authorities between different batches prepared from the same species of allergen. The method for biological standardization (BS) prescribed in the Nordic Guidelines has, for common inhalant allergens, been shown to give reproducible results between regions of Europe. However, it is difficult to define patients suitable for BS of most food allergens as well as less common inhalant allergens. Therefore we propose that, in the future, BS is replaced by determination of well-established major allergens and that 1 ng of major allergen is given the value of 1 Biological Unit.
Clinical aspects
Clinicians have had difficulties in understanding differences and similarities between units used by manufacturers for labelling of allergenic extracts. Biological standardization is time-consuming and expensive. Probably therefore, and to avoid comparison with extracts prepared by other manufacturers, most manufacturers have used their own units and few of them have used the biological units as defined by the Nordic Guidelines or FDA. Determination of the amount of major allergen by ELISA is simple and cheap. However, the biological relevance of major allergen content has not been established. Our results clearly indicate the possibility of replacing biological units by major allergen content, provided the composition of allergens is adequate. The major allergen content can easily be declared by all manufacturers. In the future, manufacturers should be forced to declare the major allergen content, thus making it easier for clinicians to compare extracts from different suppliers.  相似文献   
5.
Serum levels of tissue polypeptide antigen specific (TPS), a cytokeratin 18 marker, were determined and compared with serum levels of carcinoembryonic antigen (CEA) in 45 patients with colon adenocarcinoma and in 34 patients with benign diseases (adenomatous polyps and ulcerative colitis) at the time of diagnosis. In colon carcinoma patients 58% had an elevated TPS level (cut-off 100 U/l) and 53% had an elevated CEA level (cut-off 3.0 ng/ml). The sensitivity of the cytokeratin marker TPS was related to the stage of the disease. Significant correlation was observed between TPS and Dukes stages in colon cancer patients and the highest TPS values were achieved in Dukes stage D. The combined use of the two markers increased the sensitivity to 82% compared with the use of only one. Simultaneous raise of both serum markers TPS and CEA was observed in 36% of cases. In the majority of the patients with adenomatous polyps and ulcerative colitis the serum TPS and CEA levels were below the upper reference limit. However the initial high levels in some patients could be considered as a prognostic indicator for identifying a group of patients with increased risk of cancer development. No significant correlation was observed between serum TPS and CEA concentrations in individual patients with benign diseases.  相似文献   
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7.
The effects of intravenously administered vasoactive intestinal peptide (VIP) and secretin on bile secretion were studied in 12 patients with complete biliary fistulas. The two peptides were administered both simultaneously and separately. During VIP infusion bile volume increased by 60%, and during the combined VIP and secretin infusion bile volume increased by another 70%. VIP increased bile bicarbonate concentration by some 30%. Although secretin did not increase the concentration, bicarbonate output increased threefold during secretin infusion but only twofold during VIP infusion. The outputs of bile acids were not significantly affected by the two peptides, whereas the concentrations decreased by 40% and 70% after VIP and secretin, respectively. The canalicular bile flow, measured by [14C]erythritol, was unaffected by VIP infusion, whereas secretin alone and the combination of the two peptides increased the canalicular clearance by 80%. The choleretic effect of VIP thus seems to occur only at the ductular level. Secretin exerts its effect at the ductular level and possibly also at the canalicular level. It is concluded that the two peptides have additive effects on the ductular bile flow.  相似文献   
8.
A rapid breath hydrogen analyzer to detect lactose malabsorption is described. After ingestion of a lactose solution the patient expires into a mouthpiece attached to a hydrogen sensor at 30-min intervals for 3 1/2 h. The hydrogen of the expired air causes a voltage change that can be transformed into ppm from a calibration curve. A tolerance test with a load of 100 g lactose was performed in 43 consecutive patients with various gastrointestinal disturbances, referred to the laboratory for the commonly used lactose tolerance test based on plasma glucose measurements. Eleven patients developed symptoms of lactose intolerance during the test. Biopsy specimens from the distal duodenum or proximal jejunum showed partial villous atrophy in one, in whom celiac disease with lactose intolerance was diagnosed; the other 10 had normal specimens. In nine of them lactose intolerance was diagnosed and confirmed by observation for months on a lactose-poor diet. The 10th patient (H.P.L.) did not improve on such a diet. He also showed pronounced symptoms of intolerance during a test with monosaccharides (glucose + galactose). His intestinal disease remained undiagnosed. The 11 patients with symptoms of intolerance and 3 patients without symptoms during the lactose load showed a flat plasma glucose curve after drinking the lactose solution--that is, a maximum rise of the glucose concentration of 1.5 mmol/l. One of the symptom-free patients dropped out and could not be observed, another did not improve on a lactose-poor diet, and the third noticed a favorable effect of the diet on stool consistency but not on other abdominal symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
The 3alpha- and 3beta-reduction of the following steroids was studied in human liver microsomes: 5alpha-androstane-3,17-dione, 17beta-hydroxy-5alpha-androstan-3-one, 5alpha-pregnane-3,20-dione, 5beta-pregnane-3,20-dione, 3-oxo-5beta-cholanoic acid and 7alpha-hydroxy-5alpha-cholestan-3-one. With NADH as cofactor there was a preferential 3alpha-reduction of the C19- and C21-3-oxo-steroids and a preferential 3beta-reduction of the C24- and C27-3-oxo-steroids. Substitution of NADH with NADPH influenced reduction of the substrates in different ways, indicating the presence of several 3alpha- and 3beta-hydroxysteroid dehydrogenases with different substrate specificity and specificity towards NADH and NADPH. Only small or insignificant sex differences could be observed in the reductions studied.  相似文献   
10.
The present study aimed at determining the relative distribution of cholesterol between the vesicular and micellar phases in gallbladder bile of gallstone patients (n = 23) and gallstone-free subjects (n = 7). Nine of the gallstone patients were treated with chenodeoxycholic acid and seven were treated with ursodeoxycholic acid, 15 mg/kg/day, for 3 wk before cholecystectomy. The vesicular and micellar fractions in bile were separated by sucrose density gradient ultracentrifugation, and a clear separation between the two phases was obtained. The vesicles were further identified by quasielastic light scattering spectroscopy and appeared to be of a uniform size with a mean hydrodynamic radius of 760 A. The proportion of cholesterol in the vesicular fraction was significantly higher in the untreated gallstone group (40% +/- 4%) compared with the gallstone-free (28% +/- 3%), ursodeoxycholic acid (28% +/- 3%) and chenodeoxycholic acid (18% +/- 4%) groups. Despite a low cholesterol saturation of bile in the latter three groups (88% +/- 12%, 51% +/- 9% and 65% +/- 5%, respectively), a considerable part of the biliary cholesterol was carried in the vesicular fraction. The cholesterol/phospholipid ratio in the vesicular fraction averaged between 0.49 and 0.58 in the gallstone, gallstone-free and chenodeoxycholic acid groups, whereas the ursodeoxycholic acid group had a significantly lower ratio of 0.24. The nucleation time of bile from the gallstone group was short (2 +/- 1 days) compared with the gallstone-free, chenodeoxycholic acid and ursodeoxycholic acid groups (23 +/- 3, 24 +/- 6 and 14 +/- 3 days, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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