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1.
In dogs with cannulated gastric and duodenal fistulas, gustatory receptors were stimulated by swab application of taste stimulus solutions. The experiments were performed with fistulas open. A single taste stimulus of either 0.29 M sucrose, 0.1 M critic acid or 0.001 M quinine sulfate produced a large increase in pancreatic secretion of both volume and protein output. Sucrose was a better stimulant than citric acid or quinine sulfate for pancreatic output. After only one or two trials with each stimulant, the secretory response was no longer seen in any of the dogs. Following this extinction of the secretory response, the same dogs were given orally 100 ml of taste stimulus solution mixed with 25 g cellulose. Pancreatic secretory response occurring within 40 min following administration was gradually restored primarily for sucrose-cellulose. Oral administrations of the unpalatable citric or quinine-cellulose mixtures resulted in low pancreatic output, similar to the control water-cellulose. In contrast to oral administrations, intragastric administrations of these taste stimulus-cellulose mixtures resulted in low pancreatic output within 40 min after administration. The results suggest that taste stimulation alone does not affect pancreatic secretion. However, when coupled with swallowing, there is a greater effect by palatable than unpalatable taste stimuli on the cephalic phase of pancreatic secretion.  相似文献   
2.
A cohort of 485 couples starting their first in-vitro fertilization(IVF) attempt between January, 1989 and February, 1991 inclusive,were followed until June 1, 1992. A total of 1086 treatmentcycles were initiated (mean 2.2, range 1–6). Of these,235 (21.8%) cycles were cancelled, giving a total of 851 embryoreplacements (mean 1.7, range 1–5). After IVF treatment,189 women have either delivered or have an ongoing pregnancyin the second or third trimester. This gives a baby take-homerate of 17.4% per started cycle and 22.2% per embryo replacement.For 91 (18.6%) of the couples, the treatment was abandoned priorto completion of the three scheduled IVF attempts and 57 (11.7%)of these had no completed IVF cycles. In the group of coupleswith reduced sperm quality, the delivery rate was significantlylower than that of the other groups. A total of 193 women hadembryos cryopreserved in at least one IVF cycle; 124 of thesewomen started a frozen embryo replacement cycle and 88 had atleast one cycle with replacement of frozen/thawed embryos, resultingin 25 deliveries/ongoing pregnancies. Due to the Norwegian lawon assisted procreation 65 (33.7%) of the women have had theirfrozen embryos thawed and discarded after 12 months of storage.The cryopreservation programme, with the limitations of theNorwegian law, gives a 5.2% increase in the baby take-home ratefor women entering the IVF programme, an increase of 13.2% inthe number of ongoing pregnancies/deliveries and an 11.6% increasein number of children/viable fetuses. A total of 214 women havedelivered or have ongoing pregnancies in the second or thirdtrimester. This represents 44.1% of the 485 women accepted forIVF treatment, irrespective of whether they were treated ornot, and 50.0% of those couples who completed at least one IVFcycle.  相似文献   
3.
Genetics of the low density lipoprotein receptor:   总被引:1,自引:0,他引:1  
Fibroblast association (plasma membrane binding plus intracellular accumulation) and degradation of radioiodinated low density lipoprotein (125I-LDL) index plasma membrane LDL receptor activity. Cultured fibroblasts from 23 subjects affected with familial hypercholesterolemia (HC) and from 95 subjects without HC (non-HCs) were tested for 125I-LDL association and degradation. Both LDL receptor activity indices were twice as high in non-HC and HC heterozygous cell strains. This is compatible with a major gene effect on LDL receptor activity. However, a considerable overlap between non-HC and HC heterozygous values was found in the 125I-LDL association assay [median (range) 970 (330-2500), and 450 (250-490), respectively] and in the degradation assay [median (range) 810 (280-2020), and 470 (160-790), respectively]. The values are expressed as ng 125I-LDL X mg cell protein-1 X 4.5 h-1. These great overlaps in the LDL receptor activity indices support the view that the influence of LDL receptor activity on the HC phenotype may be smaller than believed previously. Furthermore, for the diagnosis of HC, these LDL receptor activity assays are far more expensive and have less sensitivity and specificity than simple serum cholesterol determination. The LDL receptor-dependent 125I-LDL association values for the HC heterozygous individuals clustered into four groups. Family data supported the hypothesis that this variation could be due to four different LDL receptor variants, each coded for by different alleles at the LDL receptor locus. If confirmed, this finding may have implications for the understanding of the variable expression of HC and also of the genetic impact on lipoprotein metabolism and susceptibility to atherosclerosis in non-HCs.  相似文献   
4.
Caspersson's method of labelling chromosomes with DNA-binding fluorescent agents has been applied to the study of human chromosomes. Fluorescence distribution curves of normal metaphase chromosomes treated with quinacrine mustard (QM) were obtained by scanning transparent pictures of the labelled chromosomes in a Beckman Analytrol® an instrument normally used for scanning electrophoresis strips. Representative fluorescence distribution curves of the different chromosomes, as well as one complete "QM karyotype", have been presented. The distribution curves of individual chromosomes appear to be characteristic and reproducible and it was concluded that the technique of fluorescent labelling holds great promise for identification of individual human chromosomes end chromosomal regions.  相似文献   
5.
The effect of lipid lowering diet on low density lipoprotein (LDL) receptor activity has been studied in freshly isolated peripheral blood mononuclear cells (PBMCs) from 16 hypercholesterolemic male subjects during a three weeks' dietary intervention trial. The participants were randomized to an intervention group or to a control group. The subjects in the intervention group had a non-significantly larger increase in LDL receptor activity, determined as degradation of 125I-LDL at 37 degrees C, than the control group (49.7 +/- 18.1 and 35.4 +/- 21.2 ng/mg, respectively). Irrespective of assignment to the intervention group or control group, the eight subjects with the largest reduction in total serum cholesterol had significantly larger absolute and percentage increases in LDL receptor activity than the eight subjects with the smallest reduction in total serum cholesterol (p less than 0.05). Thus, it appears that the cholesterol reduction that can be achieved in humans by dietary intervention results in a small increase in LDL receptor activity in freshly isolated PBMCs.  相似文献   
6.
BACKGROUND: Surgeons have been using selective neck dissections in the treatment of squamous carcinoma of the upper aerodigestive tract for over 20 years. To date, no data is available that can answer the question "What are the patterns of failure in the neck following a selective neck dissection and is a selective neck dissection a reliable procedure for metastatic disease?" METHODS: To answer this question, the medical records of all patients with squamous carcinoma of the oral cavity, oropharynx, larynx, and hypopharynx treated at The University of Texas M. D. Anderson Cancer Center from January 1, 1985-December 31, 1990, with a selective neck dissection were reviewed. Five hundred seventeen neck dissections were analyzed: suprahyoid (41), supraomohyoid (284), and anterolateral (192). The end point of the study was regional failure and survival. RESULTS: Regional recurrence in patients treated with a suprahyoid dissection was 43% with pathologically positive nodes. The regional recurrence in the patients treated with a supraomohyoid neck dissection was 1.9% with pathologically negative nodes, 35.7% with path N1 without postoperative radiation therapy, and 5.6% with postoperative radiation therapy. The neck staged pathologically N2B failed with and without postoperative radiation, 8.3% and 14%, respectively. Thirteen percent of the anterior/lateral neck dissections failed regionally. If multiple pathologically positive nodes (N2B) were present, the regional failure with postoperative radiation was 30% and 33.3% without postoperative radiation. CONCLUSION: The results of this retrospective study suggest that a selective neck dissection is a satisfactory staging procedure and is a definitive operation if all the nodes are pathologically negative. However, if a node is found to be invaded with cancer, the use of postoperative radiation is advisable.  相似文献   
7.
Background Duodenogastric reflux is known to cause an increased frequency of cancer in the glandular portion of the stomach in rats. Furthermore, it is debated whether inhibition of gastric acid secretion may promote gastric carcinogenesis. In the present study we examined the combined effect of gastroduodenal reflux and acid inhibition with respect to the development of gastric carcinoma in the rat.Methods Following the construction of a gastrojejunostomy in male Wistar rats, half of them were given the proton pump inhibitor lanzoprazole for 1 year. The rats were then killed and the pH in the stomach and gastrin in blood were measured. The stomach was examined macroscopically as well as histologically.Results Gastrin levels at autopsy were significantly increased in treated rats compared to the control group, confirming an effect of lanzoprazole on gastric acid secretion. Body weight was significantly reduced in the treated rats. Thirty of 79 rats developed gastric cancer, and they were all adenocarcinomas of the Lauren intestinal type. Gastric cancers occurred significantly more often in lanzoprazole-treated rats (50%) compared with controls (27%).Conclusion Lanzoprazole given orally enhances the carcinogenic effect of duodenogastric reflux in rats.  相似文献   
8.
Objective To investigate the correlation between soluble forms of the intercellular adhesion molecule (SICAM-1) and vascular cell adhesion molecule (sVCAM-1) and the severity of pre-eclampsia or its possible consequences for fetal growth.
Design Prospective observational study.
Setting Institute of Medical Genetics, University of Oslo, Department of Medical Genetics and Haematological Research Laboratory, Ullevål University Hospital; and the Department of Obstetrics and Gynaecology, The National Hospital, Oslo, Norway.
Participants Seventy-six women with normotensive pregnancies and 157 women with pre-eclampsia divided into three subgroups: mild, severe and pre-eclampsia with fetal growth retardation.
Methods ELISA-measurements of plasma SICAM-1 and sVCAM-1 were performed in a group of healthy pregnant normotensive women and three groups of women with varying degrees of pre-eclampsia.
Results SICAM-1 concentrations were higher in the pre-eclampsia group compared with the control group, but this difference was not statistically significant. Plasma concentrations of sVCAM-1 were significantly greater ( P < 0.0001) in all pre-eclampsia subgroups (835.34, 855.25 and 964.05 ng/mL) compared with the control group (667.62 ng/mL). Within the pre-eclampsia group, plasma concentration of sVCAM-1 was significantly higher in the subgroup exhibiting fetal growth retardation ( P = 0.03) compared with mild pre-eclampsia.
Conclusion The observed increases in plasma concentrations of sVCAM-1 suggest that measurements of this adhesion molecule may be useful in monitoring pregnancies with respect to the development of pre-eclampsia or fetal growth retardation.  相似文献   
9.
OBJECTIVE: To relate unexplained antepartum fetal death with maternal and fetal characteristics in order to identify risk factors. DESIGN: Population-based study based on records of 1,676,160 singleton births with gestational age > or =28 weeks. Unexplained antepartum fetal death was defined as fetal death before labour without known fetal, placental, or maternal pathology. RESULTS: Although unexplained fetal mortality in general declined from 2.4 per 1000 births in 1967-1976 to 1.6 in 1977-1998, the proportion among all fetal deaths increased from 30% to 43% during the same period of observation. Unexplained fetal death occurred later in gestation than explained. From 39 weeks of gestation, the risk increased progressively to 50/10,000 in women aged > or =35 years and <10/10,000 in women <25 years. In birth order > or =5, the risk was particularly high after 39 weeks of gestation. For birth weight percentile 2.5-9.9 and > or =97.5, unexplained fetal death was four and three times more likely to occur, respectively. We found an additive effect of maternal age and birth weight percentile 2.5-9.9. Women with less than 10 years education had higher risk than women with 13 years or more (OR=1.6). Weaker associations were observed with female gender, unmarried mothers, and winter season. CONCLUSIONS: Unexplained antepartum fetal death occurred later in gestation than explained and was associated with high maternal age, multiparity, low education, and moderately low and high birth weight percentile. The increased risk in post-term pregnancies and the additive effect of maternal age and birth weight percentile 2.5-9.9 suggests that older women would benefit from monitoring of fetal growth.  相似文献   
10.
OBJECTIVE: To validate the diagnosis of an unexplained antepartum fetal death in the Medical Birth Registry of Norway against data obtained from hospital records, alone and combined with autopsy data. To compare epidemiologic characteristics of an unexplained fetal death based on cases recorded by the three data sources. METHODS: Data on unexplained fetal deaths in the Registry were compared with clinical and autopsy data from 108 457 singletons with a gestational age >or= 28 weeks or a birthweight >or= 1000 g delivered in 1985-97 at Haukeland Hospital in Bergen and Aker Hospital in Oslo. RESULTS: Compared with clinical data, the positive and negative predictive values of a Registry diagnosis of an unexplained fetal death were 88% and 86%, respectively, while the sensitivity and specificity were 76% and 93%, respectively. Compared with clinical and autopsy data combined, the positive and negative predictive values of a Registry diagnosis of an unexplained fetal death were 77% and 89%, respectively, while the sensitivity and specificity were 78% and 88%, respectively. High agreement was observed in comparisons between the data sources of risks according to various independent variables. CONCLUSIONS: The validity of a diagnosis of an unexplained antepartum fetal death based on the Medical Birth Registry of Norway is sufficiently high to justify future large-scale epidemiologic studies based on this database.  相似文献   
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