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排序方式: 共有1245条查询结果,搜索用时 31 毫秒
941.
Intrahepatic biliary strictures after liver transplantation 总被引:14,自引:0,他引:14
942.
Gallbladder contraction and hormone release were measured in six healthy volunteers after their ingestion of two commercially available fatty meals (Biloptin Fatty Meal and Sorbitract) and intravenous bolus injection of 1 Ivy Dog Unit/kg body weight cholecystokinin (CCK) to compare the effectiveness of fatty meals to CCK. Differences in gallbladder volumes, rate constants of emptying, and times of maximal contractions, as measured by real-time sonography, were not statistically significant. Peak levels of CCK, a potent stimulant of gallbladder contraction, and of pancreatic polypeptide, an inhibitor of gallbladder contraction, were significantly higher (P less than .05-P less than .005) after administration of CCK than after ingestion of each fatty meal, but this did not significantly affect emptying rate or maximal contraction. We conclude that the use of intravenous CCK does not offer any advantage over the ingestion of fatty meals in radiographic studies of gallbladder involving induced contractions. 相似文献
943.
944.
945.
RS Procianoy JA Garcia-Prats JM Adams A Silvers AJ Rudolph 《Archives of disease in childhood》1980,55(7):502-505
19 small for gestational age (SGA) infants with gestational ages less than or equal to 32 weeks were matched with 19 appropriate for gestational age (AGA) preterm neonates with similar risk factors for intraventricular haemorrhage and hyaline membrane disease. Gestational age, 1- and 5-minute Apgar scores, type of delivery, survival rate, use of corticosteroids before delivery, sex, twinning, presence of premature rupture of membranes, and birth date were comparable in the two groups. Gestational age of both groups was 30 (+/- 1.8) weeks, and birthweights were 919 (+/- 202) g (SGA group) and 1268 (+/- 212) g (AGA group). The incidences of hyaline membrane disease and intraventricular haemorrhage were different: 74 and 42% respectively for AGA neonates, 5 and 11% respectively for SGA infants. We suggest that a stressful environment in utero may enhance maturation and prevent hyaline membrane disease and intraventricular haemorrhage. 相似文献
946.
A wide variety of clinical and biochemical manifestations have been reported in association with pseudohypoparathyroidism and associated disorders. This is illustrated by a family study in which the affected members show widely differing characteristics. 相似文献
947.
Two patients are described with chronic hypoglycaemia; the first having glucose-6-phosphatase deficiency (type I glycogen storage disease), and the second fructose 1:6-diphosphatase deficiency. Both cases were associated with a bleeding diathesis, a defect of platelet aggregation, and a deficiency of platelet adenine nucleotides. The effect on the platelet abnormalities of a period of normoglycaemia was studied in both patients. Correction of the platelet abnormalities occurred rapidly after stabilization of the blood glucose within the normal range. Normal function persisted for the duration of the normoglycaemia, facilitating diagnostic liver biopsy and surgical procedures. A biochemical explanation for the nucleotide deficiency is suggested. 相似文献
948.
Intestinal and extra-intestinal tumor multiplicities in the Apc1638N mouse model after exposure to X-rays 总被引:1,自引:0,他引:1
van der Houven van Oordt CW; Smits R; Williamson SL; Luz A; Khan PM; Fodde R; van der Eb AJ; Breuer ML 《Carcinogenesis》1997,18(11):2197-2203
Seven-week-old Apc1638N mice were exposed to a single dose of 5 Gy
total-body X-irradiation resulting in a 8-fold increase in the number of
intestinal tumors and a reduction of the lifespan to an average of 6
months. The distribution of tumors along the intestinal tract as well as
the adenoma/carcinoma ratio, were similar between non-irradiated and
irradiated animals. Semi-quantitative PCR analysis of intestinal-tumor DNA
revealed that 10 out of 14 tumors had lost the wild-type Apc allele.
However, in contrast to spontaneous Apc1638N intestinal tumors in which the
LOH event at the Apc locus involves the entire chromosome 18 (1), in 6 out
of 10 tumors derived from X-irradiated animals the Apc loss is associated
with only a partial intrachromosomal deletion. The remaining tumors have
lost all chromosome 18 markers tested. In addition to the intestinal
tumors, female Apc1638N mice are susceptible to the development of mammary
tumors. Upon X-irradiation, Apc1638N mice show a striking 15-fold increase
in mammary tumors. Moreover, Apc1638N mice spontaneously develop other
extra-intestinal neoplasia, such as desmoid-like lesions similar to those
associated with familial adenomatous polyposis (FAP), the human syndrome
caused by germline mutations in the APC gene. Spontaneous desmoid growth is
sex-dependent, as male Apc1638N mice develop 3-fold more desmoids than
female mice. Interestingly, X-irradiation seemed to increase the number of
desmoids per animal nearly twofold only in female Apc1638N mice. Five out
of 9 desmoids found in Apc1638N mice exposed to X-ray displayed loss of the
wild-type Apc allele.
相似文献
949.
A potential danger of bedclothes covering the face 总被引:1,自引:0,他引:1
AJ Campbell DPG Bolton SM Williams BJ Taylor 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(3):281-284
Investigations of infants dying unexpectedly have reported up to 28% being found completely under bedding. No detailed physiological studies looking at the possibilities of asphyxia in this situation are available. The aim was to determine the potential for asphyxia under different types and thicknesses of bedding. A mechanical model of a 3-month-old infant's respiratory system was used. Bedding was positioned over the head in a supine position, and inspired carbon dioxide recorded. With a fixed respiratory rate and tidal volume, carbon dioxide accumulation increased with increasing layers of blankets. Up to 8.3% inspired carbon dioxide was recorded with more than four layers of blankets. A cotton sheet between the face and blankets reduced the accumulation by half. An infant found dead under bedding may have been exposed to an asphyxial stress. Suffocation from rebreathing trapped, expired gases can be a cause of death in this situation. 相似文献
950.