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81.
In the term human and ovine fetus, plasma gastrin is elevated, but gastric acid secretion is below adult levels, suggesting a developmentally related immaturity in gastrin and gastric acid regulation. This study investigated a number of elements of the gastric acid regulatory system: gastrin and its glycine-extended precursor, somatostatin, and the H+/K(+)-ATPase. Measurements were made in blood, antrum, and fundus of the ovine fetus during the last half of gestation, of 15-day-old lambs, and of adult sheep at the level of mRNA synthesis, tissue storage, and secretion. Plasma amidated gastrin (gastrin-amide) was elevated at or above adult values from 125 days (term is 145 days) and steadily increased with development, peaking in the lamb. Similar changes occurred with plasma glycine-extended gastrin (gastrin-gly). The peak concentration of antral gastrin-amide was present in the lamb, while the maximum antral gastrin-gly level occurred 1 week before birth. Gastrin mRNA paralleled the changes in antral gastrin-gly. The proportion of higher mol wt species of gastrin decreased during gestation in both plasma and antrum. Low amounts of mRNA for the H+/K(+)-ATPase was present from at least 120 days of gestation and antedated gastric acid secretion. However, there was a 3-fold increase in H+/K(+)-ATPase mRNA from the 140-day-old fetus to the lamb, the period when the greatest reduction in gastric pH occurred (pH 5 to 2). Antral and fundic somatostatin increased rapidly in the fetus at 120 days gestation and were above adult values at term and in the lamb. Somatostatin mRNA changed in parallel to somatostatin peptide. Somatostatin-14 was the major species in antrum and fundus throughout development. The increase in circulating and antral gastrin-amide after birth may be the result of increased amidation of gastrin-gly as well as increased expression of gastrin mRNA. Amidation of gastrin may be a regulatory step in the production of biologically active gastrin during development. The major increase in gastrin and the H+/K(+)-ATPase that occurs in the week before and after gestation correlated with the onset of increased gastric acidity. 相似文献
82.
Dr. M. Leela Prasad M.D. Don R. Read M.D. Herand Abcarian M.D. 《Diseases of the colon and rectum》1981,24(6):456-461
Anorectal suppurations are quite common. Supralevator abscesses, previously regarded as a rare subgroup, were seen in 9.1
per cent of 506 patients admitted to Cook County Hospital in a two-year period. Aggressive supportive management was followed
by early, adequate drainage through single or multiple radial perianal incisions or through the rectum whenever indicated.
When fistulas were identified, either a primary fistulotomy or a two-stage fistulotomy using a seton was performed in the
majority of cases. Important factors in the prevention of morbidity and mortality included debridement of all necrotic tissue,
careful bacteriologic studies and judicious use of antibiotics, close postoperative observation, and long-term follow-up of
the patients.
Read at the meeting of the American Society of Colon and Rectal Surgeons, Hollywood, Florida, May 11 to 16, 1980. 相似文献
83.
Dr. Roberta Barbera MMedSci Christine Feinle Prof. Nicholas W. Read MA MD BChir 《Digestive diseases and sciences》1995,40(8):1636-1641
Intraduodenal lipid infusion induces symptoms and increases sensitivity to gastric distension in patients with functional dyspepsia. To test whether these effects are specific for lipid, we compared the effects of intraduodenal infusions of either lipid or glucose on symptoms and gastric sensory and motor responses to gastric distension. Eighteen dyspeptic patients and nine controls were studied. The stomach was distended with a flaccid bag during isocaloric infusions (1 kcal/ml) of saline and either 10% Intralipid (nine patients) or 26.7% glucose (nine patients) into the duodenum. Dyspeptic symptoms and sensory thresholds for epigastric fullness and discomfort were assessed. Gastric pressure profiles during distensions were similar during lipid and glucose infusions in patients and controls, but both were significantly lower than during saline infusion. Lower volumes were required to induce fullness and discomfort in the patients compared with the controls. In the controls, the threshold volumes required to induce fullness and discomfort were greater during infusion of lipid and glucose than during saline infusion, but in the patients, the threshold volumes were increased during glucose infusion but further reduced during lipid infusion. Moreover, in the patients, nausea was more common during lipid than glucose infusion and did not occur during saline. The controls did not experience any symptoms during any infusion. In conclusion, intraduodenal lipid but not glucose sensitizes the stomach to distension in patients with functional dyspepsia but not in controls. 相似文献
84.
Sonja M. Garnaut Gordon S. Howarth Leanna C. Read 《Growth factors (Chur, Switzerland)》2013,31(1):17-25
The relationship between insulin-like growth factor-I (IGF-I) peptide-induced increases in bowel mass and functional improvement is unclear. We utilised three independent methods to investigate the effects of IGF-I peptides on intestinal absorption of the glucose analogue, 3- O -methyl- d -glucose (3MG) in rats. Rats received vehicle, IGF-I or the more potent analogue, long-R 3 -IGF-I via subcutaneously implanted mini-pump, for 7 days, at which time intestinal absorption was assessed by: (1) plasma 3MG appearance following oral gavage, (2) single-pass- or (3) recirculating-perfusion of a jejunal segment. 3MG (320 or 800 u mg) was gavaged on day 7 to rats treated with vehicle, IGR-I or long-R 3 -IGF-I. With the lower 3MG dose, only long-R 3 -IGF-I increased (40%) the initial rate of 3MG appearance in plasma. IGF-I had no significant effect, whilst at the higher 3MG dose neither peptide was effective. Utilising perfusion techniques, long-R 3 -IGF-I, but not IGF-I, significantly increased 3MG uptake per cm of jejunum by up to 69%, although significance was lost when expressed as a function of tissue weight. Long-R 3 -IGF-I, but not native IGF-I, enhanced 3MG absorption from the intestinal lumen, presumably reflecting an increased mucosal mass rather than an up-regulation of specific epithelial glucose transporters. 相似文献
85.
Alison?Kate?LillieEmail author Sue?Read Christian?Mallen Peter?Croft John?McBeth 《BMC palliative care》2013,12(1):27
Background
Pain is an important issue in end of life care. Although musculoskeletal pain is common in older adults, it is rarely associated with the cause of death and may be overlooked as death approaches. Hence a major target for improving quality of life may be being missed.Methods
The aim of this study was to systematically search and critically review the literature on musculoskeletal pain at the end of life. Amed, Cinahl, Internurse, Medline, Psych Info, Web of Knowledge and Cochrane review databases were searched for relevant research up to September 2012. The search strategy combined key words expanding the terms ‘palliative’ for population, ‘musculoskeletal’ for exposure, and ‘pain’ for outcome. Predefined inclusion and exclusion criteria were applied.Results
Five relevant papers and one letter to the editor were found, including case studies and epidemiological research. Current evidence suggests musculoskeletal pain is common in older adults at the end of life and that it can have a substantial impact on individual experience. No information about community based treatment of musculoskeletal pain at the end of life was found.Conclusion
Priorities for future research include high quality epidemiological studies to establish the prevalence, natural history, impact, assessment, patient priorities and outcomes associated with musculoskeletal pain in the end of life period, and intervention research that provides an evidence base for treatment.86.
IgG autoantibodies eluted from RBCs of antiglobulin positive normal blood donors contained at least two antibody populations, an IgG autoantibody (Ab 1), and an IgG population (Ab 2) that agglutinated RBCs coated with some Rh(D) alloantibodies. Eight of 24 autoantibody eluates tested agglutinated 3 of 10 anti-Rh(D) sensitized RBCs. The agglutinating activity was inhibited specifically by preincubation of the autoantibody eluate with the reactive anti-D. The reaction did not require the Fc domain of the anti-Rh(D), since autoantibody eluates agglutinated RBCs coated with F(ab')2 prepared from the reactive anti-D sera. These findings indicate that the RBCs of some antiglobulin- positive blood donors contain an immunoglobulin auto-antiidiotype (Ab 2) against the RBC autoantibody (Ab 1) which is demonstrable through its cross-reactivity with selected Rh(D) alloantibodies. Identification of auto-antiidiotypes in RBC autoimmunity lends support to the idiotype- antiidiotype network hypothesis of immune regulation and is consistent with the bizarre and complex serology of autoimmune hemolytic anemia. The absence of clinical hemolysis in antiglobulin-positive normal blood donors suggests that immunoglobulin idiotype-antiidiotype interactions may play a role in modulating the effects of RBC autoimmunity. 相似文献
87.
The ability of subjects to expel from the rectum objects simulating stools of different characteristics was assessed in paired studies carried out in a total of 58 normal subjects and 25 young women with severe constipation. Our results showed that a lower percentage of normal subjects and a lower percentage of constipated patients were able to pass a 1.8 cm incompressible sphere compared with a 50 ml deformable balloon, although constipated patients found it more difficult than normal subjects to expel both types of simulated stool. It was also more difficult for normal subjects to pass a soft compressible silicon rubber simulated stool than a stool made up of a similar volume of incompressible 1 cm wooden spheres contained in a cylindrical latex envelope, but both objects were much easier to pass than the same number of 1 cm spheres placed loose within the rectum. When normal subjects were instructed to expel single incompressible spheres of different sizes placed in the rectal ampulla, the intrarectal pressure and the time needed to pass these objects varied inversely with their diameter. These results suggest that more effort is required to expel stools from the rectum if they are small and hard than if they are large and soft. 相似文献
88.
Adaptation of hydrogen analysis to measure stomach to caecum transit time in the rat 总被引:2,自引:0,他引:2
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Excreted hydrogen analysis was used to measure stomach to caecum transit time of the head of a test meal in 120 rats fed by gavage. Results were compared with the distribution of a labelled test meal in the gastrointestinal tract of rats killed at different time intervals after gavage. Values for stomach to caecum transit were compatible with the distribution of labelled meals in 91% of animals, although in the remainder the hydrogen concentration had not risen even though food residues were in the caecum when the animals were killed. The technique gave reproducible results; the coefficients of variation for four studies carried out in each of six animals varied between 4 and 14%. A meal consisting of homogenised baked beans had a significantly shorter stomach to caecum transit time (88.1 +/- 4.5 min; mean +/- SE; n = 21; p less than 0.001) than an equivalent volume of Complan/lactulose (180.9 +/- 8.7 min; n = 13). This technique was used to investigate the effect of ileal infusion of a fat emulsion (20% Intralipid) via a chronically implanted intestinal cannula on the stomach to caecum transit time of a bean meal, in a series of paired studies carried out in six rats. Stomach to caecum transit time was significantly delayed during ileal infusion of 20% Intralipid compared with the control infusion of an isotonic saline solution (218.3 +/- 21 min v 106.7 +/- 33 min Intralipid v saline; n = 6; p less than 0.001). 相似文献
89.
Hemostatic plug (HP) formation was investigated in the ear bleeding time incision in normal and von Willebrand pigs. HP volume was calculated by integrating the areas of serial sections. In normal pigs (n = 11), platelets immediately formed a layer on the surface of the cut channel. Platelet aggregates formed at the ends of transected vessels and gradually enlarged. Finally, all transected vessels were occluded by HP and bleeding stopped. In contrast, large HPs were formed in the incision in von Willebrand's disease (vWD) pigs (n = 4); these HPs did not cover the ends of the transected vessels, which continued to bleed, allowing the formation of large hemostatically ineffective platelet aggregates in the incision. Canals traversed these HPs, and bleeding from the open vessels may have continued through them. After infusion of cryoprecipitate into a vWD pig, the bleeding time shortened, and the morphological findings of the HPs were similar to those of normal pigs. In normal pigs (n = 3) infused with an anti- Willebrand factor monoclonal antibody, which prolonged the bleeding time, a large HP formed in the incision, similar to that observed in the vWD pig. The volume of the normal and vWD HPs increased with time. These in vivo findings suggest that Willebrand factor is involved in the localization of the HP to the damaged vessel and may also play a role in platelet-platelet interaction. A computerized morphometric technique was used for measuring the volume of the hemostatic plugs and the distance of sequential points on the perimeter of the HP from the center of selected bleeding vessels. 相似文献
90.
Use of anorectal manometry during rectal infusion of saline to investigate sphincter function in incontinent patients 总被引:18,自引:0,他引:18
N W Read W G Haynes D C Bartolo J Hall M G Read T C Donnelly A G Johnson 《Gastroenterology》1983,85(1):105-113
Anal and rectal pressures and external sphincter electromyogram were recorded continuously during rectal infusion of 1.5 L saline in 18 normal subjects and 37 patients who complained of diarrhea and fecal incontinence. All subjects exhibited a pattern of regular fluctuations in anorectal pressure and electromyogram. All except 1 of the normal subjects were able to retain 1500 ml saline without leakage, and their pressure record comprised simultaneous rectal contractions, internal sphincter relaxations, and external sphincter contractions. None of the incontinent patients were able to retain 1500 ml saline without leakages, and leakages always coincided with the peaks of rectal pressure. Two manometric patterns were observed. Fifty-nine percent of incontinent patients exhibited a pattern of contractions of similar profile occurring throughout the anorectum. This finding was associated with low basal sphincter pressures, an easily inhibited anal sphincter tone, an obtuse anorectal angle, and a funnel-shaped configuration to the anal canal. These results suggested that, in this group, the internal sphincter was weak and easily inhibited so that the whole anorectum behaved as one fluid-filled compartment recording contractions of the external sphincter. The remaining 41% of incontinent patients exhibited a normal pattern of anorectal pressure fluctuations and had normal maximum basal pressures, although maximum squeeze pressures, rectoanal inhibitory reflex, and anorectal angles were abnormal. Peak rectal pressures were abnormally high in this group during saline infusion, suggesting that abnormally strong rectal contractions may play a role in the incontinence in this group. 相似文献