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1.
Real time ultrasonography was used to compare the prevalence of gall stones in two groups of women aged 40-69: 632 women recruited from general practice registers and 130 vegetarians. One hundred and fifty-six (25%) of the 632 women who ate meat and 15 (12%) of the 130 vegetarian women either had gall stones visible on ultrasonography or had previously undergone cholecystectomy (p less than 0.01). The prevalence of gall stones was found to increase with age and body mass index. The 2.5 fold increase in risk of developing gall stones in non-vegetarians compared with vegetarians was reduced to 1.9 when controlling for these two potentially confounding factors, but remained significant. A family history of gall stones was reported more often by women with gall stones, but no association was found with parity or use of exogenous oestrogens. Thus the importance of age and obesity to determine the prevalence of gall stone was confirmed, and a dietary factor associated with vegetarianism may prevent this common condition.  相似文献   

2.
The prevalence of gall stones (100% cholesterol) in a deer mouse (Peromyscus maniculatus) population located in Siskiyou County, California (USA) was studied on a monthly basis from February 1985 through January 1988. During each year we documented a pronounced annual cyclicity with peak prevalence (31 to 53%) during the winter and low prevalence (2 to 3%) during late summer. Gall stone prevalence was not related to sex or age of the animal. The earliest onset of gall stone production and the maximum prevalence achieved were associated with the greatest abundance of deer mice; lower levels of population abundance were associated with later onset of gall stone production and lower peak prevalences. This association of gall stone prevalence with both season and population abundance levels suggests that the causative factor(s) is/are related to the quality and availability of the diet.  相似文献   

3.
The prevalence of gall stones was studied prospectively by abdominal ultrasound examination in 131 patients with sickle cell disease aged 10-65 years. Of 95 patients with homozygous sickle cell disease, 55 (58%) had gall stones or had had a cholecystectomy. Gall stones were present in four out of 24 (17%) patients with haemoglobin S + C disease and two out of 12 (17%) with haemoglobin S beta thalassaemia. The presence of gall stones was not related to sex, geographical origin, or haematological variables and was not associated with abnormal results of liver function tests. Symptoms typical of biliary colic were reported by 32 out of 47 adult patients with gall stones, and cholecystitis or cholestasis was diagnosed in 18. Cholecystectomy was performed in 29 patients with good relief of symptoms in most cases. Postoperative complications were common, occurring in 10 of the 28 patients who could be evaluated, but not generally serious; they were considerably lessened by a preoperative exchange transfusion that reduced the haemoglobin S concentration to below 40%. It is suggested that all patients with sickle cell disease should be screened for gall stones and that elective cholecystectomy should be performed in those with symptoms or complications.  相似文献   

4.
During the decade in which the medical dissolution of gall stones has become feasible several drugs have been introduced but only the two listed in the British National Formulary have been intensively evaluated and shown to be effective--chenodeoxycholic acid and the closely allied ursodeoxycholic acid. The dissolution of gall stones was last reviewed in the "BMF" in 1976, at which stage experience with chenodeoxycholic acid was limited. Since then the indications and potential for this bile acid in treating gall stones have become better understood, and data on the newly introduced ursodeoxycholic acid are being evaluated. Cholesterol, but not pigment, gall stones are amenable to oral dissolution treatment. This review will cover firstly, chenodeoxycholic acid, secondly, ursodeoxycholic acid, then a comparison of the two drugs, an assessment of the place of medical dissolution in the management of gall stones, and, finally, the dissolution of stones in the common bile duct.  相似文献   

5.
Many parasitic organisms have an ability to manipulate their hosts to increase their own fitness. In parasitoids, behavioral changes of mobile hosts to avoid or protect against predation and hyperparasitism have been intensively studied, but host manipulation by parasitoids associated with endophytic or immobile hosts has seldom been investigated. We examined the interactions between a gall inducer Masakimyia pustulae (Diptera: Cecidomyiidae) and its parasitoids. This gall midge induces dimorphic leaf galls, thick and thin types, on Euonymus japonicus (Celastraceae). Platygaster sp. was the most common primary parasitoid of M. pustulae. In galls attacked by Platygaster sp., whole gall thickness as well as thicknesses of upper and lower gall wall was significantly larger than unparasitized galls, regardless of the gall types, in many localities. In addition, localities and tree individuals significantly affected the thickness of gall. Galls attacked by Platygaster sp. were seldom hyperparasitized in the two gall types. These results strongly suggest that Platygaster sp. manipulates the host plant''s development to avoid hyperparasitism by thickening galls.  相似文献   

6.
In a combined historical and radiological survey gall stones were found in 23 out of 72 patients with disorders of the terminal ileum (31·9%). This is four to five times the expected incidence of cholelithiasis. In these patients the incidence of gall stones was not related to age, but did, however, increase with increased duration of the ileal disorder. Glycine/taurine conjugation ratios of bile salts in the bile were abnormally high in 10 out of 11 patients with ileal disorders. Both impaired bile salt recirculation and absorption of poorly soluble bacterially degraded bile salts are possible causes of cholelithiasis in these patients.  相似文献   

7.
《BMJ (Clinical research ed.)》1975,4(5994):427-430
Necropsy records from two large general hospitals in Dundee showed short-term fluctuations in the prevalence of gall stones that had not previously been described. There was no evidence of a rise in the standardised prevalence rate between 1902-9 and 1953-73. A spurious increase was apparent from the crude prevalence rates for these periods, which resulted simply from the increased age of the patients in the later period. Since there was no real increase in prevalence no conclusions can be drawn about dietary or other changes. Patients with stones in the common bile duct were likely to die from an associated cause. This related mainly to a high mortality rate in women. In patients with established epilepsy the prevalence of gall stones was greater than expected, which suggests that phenobarbitone does not diminish the likelihood of gall stones.  相似文献   

8.
Gall bladder and hepatic bile was sampled from 66 patients undergoing elective operations on the biliary tract. Fifty-one patients had cholesterol gall stones but only 59% of these were found to have bile which was supersaturated with cholesterol. Repeated sampling of hepatic bile from patients with T-tubes showed that the secretion of supersaturated bile was intermittent.These results indicate that it is impossible to separate patients with cholesterol stones from controls simply by examination of the lipid composition of their bile, since an appreciable number of bile samples from patients with cholesterol stones were unsaturated.The fact that cholesterol gall stones form when the bile is supersaturated with cholesterol only intermittently suggests that the gall bladder may also have a part in their formation.  相似文献   

9.
The factors influencing the migration of gall stones are ill understood. Altogether 331 patients undergoing cholecystectomy were studied prospectively. The diameters of the cystic and common bile ducts and of stones in the gall bladder and bile ducts were measured. Increasing pressure was applied to the freshly excised gall bladder in an attempt to evacuate stones through the cystic duct. Stones passed in 33 (60.0%) of patients with choledocholithiasis, 45 (67.2%) of patients with pancreatitis, and 7 (3.2%) of patients without either pancreatitis or choledocholithiasis. Stones migrated in 6 (3.0%) who had a normal cystic duct diameter (less than or equal to 4 mm) and in 46 (32.5%) with a duct over 4 mm diameter. Common bile duct stones were often larger than the diameter of the cystic duct and when reintroduced into the gall bladder would not migrate. The passage of debris (less than or equal to 1 mm) through the cystic duct bore no relation to the presence or absence of choledocholithiasis or a dilated cystic duct. Small stones (1-4 mm diameter) must migrate to initiate and facilitate further migration; some must increase in size in the common bile duct. Increased biliary pressure consequently dilates the duct system retrogradely, allowing larger stones to follow. Patients at risk of stone migration and thereby pancreatitis and jaundice have large ducts that can be detected by ultrasound assessment.  相似文献   

10.
Oral cholecystography repeated at six-months intervals is the standard method for determining reduction in size of gall stones (partial success) and complete dissolution of stones (complete success). In a comparative study of oral cholecystography and cholecystosonography six out of 14 patients with gall stones achieving complete success by oral cholecystographic criteria had stones still detectable by ultrasonography. Repeat oral cholecystography in a further 11 patients receiving post-dissolution maintenance treatment detected stones in two, whereas ultrasonography detected stones in seven. In future complete dissolution of gall stones should be reported only if both oral cholecystography and ultrasonographic studies give negative results and the progress of patients receiving post-dissolution maintenance treatment is monitored by ultrasonography rather than serial oral cholecystography.  相似文献   

11.
A prospective study of the prevalence of gall stones at necropsy in nine towns in England and Wales showed considerable geographical variations. The age- and sex-standardised prevalence ranged from 20.6% in Ipswich to 9.2% in Wakefield. The distribution of gall stones differed from that of all-cause mortality and was negatively correlated with that of mortality from ischaemic heart disease. Socioeconomic influences related to affluence do not appear to be major determinants of the distribution of gall stones.  相似文献   

12.
Leah Flaherty  Dan Quiring 《Oikos》2008,117(11):1601-1608
Several different hypotheses attribute large variations in gall abundance and galler performance to variations in plant growth rate and/or module size. The plant vigor hypothesis (PVH) predicts that galler performance will be greatest on large, fast‐growing plant modules due to their large, rapidly dividing cells that allow them to make large galls, where survival and size of survivors are usually greater. The optimal module size hypothesis (OMSH) predicts that galler performance will be greatest on intermediate‐sized modules, based on a tradeoff between ease of gall induction on small modules and increased resource availability in large modules. Here, we evaluate predictions of the PVH and OMSH during a two‐year field study by examining gall induction and full gall development success, as well as subsequent galler performance in successfully developed galls, using a shoot galling adelgid, Adelges abietis, on white spruce Picea glauca. In addition, we tested whether increased dose of gall induction stimulus on different sized modules, achieved by observing differing A. abietis densities per bud, could increase the rate of successful gall induction, as predicted by the OMSH. Galls of A. abietis appeared to be induced by a dose‐dependent stimulus from fundatrices in spring. Furthermore, the critical stimulus dose required to induce a gall appeared to increase with shoot length. These findings support the OMSH and not the PVH. Galler performance (gall volume and the number of gallicolae that emerged from each gall) in successfully developed galls was positively related to shoot length, supporting both the PVH and OMSH. We conclude that the PVH represents one component of the more inclusive OMSH, which considers both ease of gall induction on different‐sized modules and the effect of plant module size on gall size.  相似文献   

13.
角倍蚜虫瘿对盐肤木光合特性和总氮含量的影响   总被引:2,自引:0,他引:2  
李杨  杨子祥  陈晓鸣  刘平  唐翊峰 《生态学报》2013,33(21):6876-6884
通过温室栽培和接种实验,以接种角倍蚜形成虫瘿的盐肤木和未接种角倍蚜的盐肤木为实验材料,测定和分析虫瘿对盐肤木光合特性和不同组织氮含量的影响。结果表明虫瘿对盐肤木的光合作用形成扰动,与对照植株相比较:(1)有虫瘿复叶的最大净光合速率升高,其中虫瘿初期、中期和后期分别升高14.49%、32.17%和42.01%;虫瘿还引起无虫瘿复叶最大净光合速率升高,但中期以后下降到正常水平;(2)虫瘿中期有虫瘿复叶的光饱和点升高、无虫瘿复叶光饱合点下降;虫瘿初期和中期有虫瘿复叶的光补偿点升高、无虫瘿复叶光补偿点下降;(3)虫瘿初期引起有虫瘿复叶及邻近无虫瘿复叶暗呼吸速率升高,但中期和后期影响不显著。虫瘿对盐肤木光合作用的扰动程度与小叶的位置和虫瘿生长时期密切相关。同时,虫瘿改变了盐肤木叶片氮含量分布,其中虫瘿外壁、有虫瘿复叶和无虫瘿复叶的氮含量分别为1.13%、1.98%和2.14%,这可能是营养物质从无虫瘿复叶流向有虫瘿复叶,并最终流向虫瘿,满足虫瘿和瘿内蚜虫生长需求的原因。  相似文献   

14.
A case-control study of gall stone disease in women in relation to use of contraceptives, reproductive history, and concentrations of endogenous hormones was undertaken. The study population comprised 200 hospital patients with newly diagnosed gall stone disease, 182 individually matched controls selected from the community, and 234 controls who were patients in hospital. Use of oral contraceptives was associated with an increased risk of developing gall stones among young subjects but a decreased risk among older subjects. The risk of developing gall stone disease increased in association with increasing parity, particularly among younger women. The risk fell with increasing age at first pregnancy, independent of parity. Mean urinary excretion over 24 hours of oestrone, but not of pregnanediol, was significantly (p less than 0.05) greater for postmenopausal patients than controls. The age dependence of the relative risk associated with exposure to oral contraceptives and pregnancy suggests that there are subpopulations of women susceptible to early formation of gall stones after exposure to either oral contraceptives or pregnancy.  相似文献   

15.
In most patients with radiolucent gall stones who were given chenodeoxycholic acid (CDCA) in doses of 13-15 mg/kg body weight/day the bile became unsaturated in cholesterol, and their gall stones dissolved. The patients whose stones did not dissolve were significantly heavier and fatter than the responders, which suggested that obese patients might be “resistant” to the effects of CDCA. To test this hypothesis, 32 consecutive patients presenting for medical treatment of gall stones had their ideal body weight (IBW) and estimated body fat mass calculated. The eight most obese and the eight least obese patients were then selected, and their fasting bile lipid responses to CDCA 13-15 mg/kg/day were measured. The very obese patients were also given larger doses, and any changes in bile lipid composition were studied in relation to subsequent gall-stone dissolution.Before treatment the obese patients had a higher mean biliary cholesterol saturation index than the non-obese patients, and this difference was maintained during treatment with the normal dose of CDCA: the bile in the obese patients remained supersaturated while that in the non-obese became unsaturated with cholesterol. When the obese patients were given larger doses of CDCA their bile ultimately became unsaturated in cholesterol. Gall stones dissolved partially or completely in five of the eight non-obese patients after 6-18 months of 13-15 mg CDCA/kg/day, but none of the obese patients showed any response after comparable periods of treatment with this standard dose. With increased doses and unsaturated bile, however, three of the obese patients showed partial gall-stone dissolution after 3-12 months'' treatment and one showed complete gall-stone dissolution after three years'' treatment.These results suggest that when giving CDCA to patients with gall stones, larger than normal doses (some 18-20 mg/kg/day) should be prescribed. Alternatively the lipid composition of the patients'' bile should be monitored by duodenal intubation and the CDCA dose increased until the bile becomes unsaturated in cholesterol.  相似文献   

16.
Hypercholesterolaemia has been predicted as a possible complication of chenodeoxycholic acid treatment for gall stones. To exclude this, fasting serum lipids were measured in patients with stones before and at monthly intervals for six months after starting chenodeoxycholic acid. Before treatment half of a group of 36 patients with presumed cholesterol gall stones had serum cholesterol levels exceeding 260 mg/100 ml or serum triglyceride values greater than 160 mg/100 ml or both; these lipid levels were significantly greater than those in control subjects matched for age and sex. Treatment with chenodeoxycholic acid (0·5-1·5 g/day by mouth) did not change serum cholesterol levels but did significantly reduce serum triglyceride concentrations from a pretreatment level of 118 (± S.E. of mean 11·7) mg/100 ml to 95 (± 7·2) mg/100 ml after six months of therapy. The mechanism of this triglyceride-lowering action of chenodeoxycholic acid is not known, but it may have therapeutic value in patients with hypertriglyceridaemia.  相似文献   

17.
Fluctuating asymmetry (FA) is defined as small and random deviations from perfect symmetry in otherwise bilaterally symmetrical traits. Usually, plants under stress have a higher nutritional quality and are preferred by insect herbivores. Here, we examined the relationship among leaf FA of Bauhinia brevipes (Fabaceae), nutrients and the occurrence of Schizomyia macrocapillata (Cecidomyiidae: Diptera). We evaluated whether: (i) FA was related to S. macropillata abundance and survivorship; (ii) FA correlated with the levels of foliar nutrients (macro- and micronutrients, and organic carbon); and (iii) S. macropillata abundance was related to leaf nutrients. The results showed a positive relationship between FA and gall abundance. S. macrocapillata survivorship was five times higher in B. brevipes individuals with high FA levels, but this difference was not significant. The influence of nutrients in B. brevipes FA was negligible, except for foliar nitrogen, which was 7.3% higher in plants with low FA levels. The abundance of S. macrocapillata was negatively related to nitrogen levels, but gall survivorship was not affected by this nutrient. We found evidence for a causal relationship between FA and gall occurrence, since S. macropillata gall oviposition occurs in young undeveloped leaves, thus mature leaves show an increase in FA. Nonetheless, in this system, neither FA nor nitrogen influenced gall survivorship.  相似文献   

18.
In an unusual case involving a candidate biological control agent, the histologically complex stem galls of the weevil, Rhinusa pilosa (Coleoptera: Curculionidae) on yellow toadflax (Linaria vulgaris), are rapidly induced during oviposition and reach full size by larval hatch. To investigate gall induction, the oviposition behavior of R. pilosa was described. We experimentally disrupted ovipositing weevils at three key points in the oviposition sequence and compared host-plant tissue responses post disruption, to what occurs during normal gall induction using histological methods. De novo xylem production, intercellular spaces in the cortex, and hyperplasia and hypertrophy of the procambium and pith parenchyma surrounding the egg were some of the tissue- and cellular-level modifications observed only 3?C5?days after normal oviposition. Normal gall development was not observed after any of the oviposition disruption treatments, although some of the cellular and tissue responses resembled those found after undisrupted oviposition. Feeding by the female during oviposition canal formation induced wound meristem and callus tissue formation, but no other modifications consistent with gall formation. When females were disrupted about 20?s into oviposition, a homogenously dense substance was observed, which was suspected to be ovipositional fluid. There was minor stem swelling 10?days later and histologically, periclinal cell divisions, de novo xylem, and pith cells with numerous stained plastids were observed as in normal gall development, thus suggesting that ovipositional fluid plays a role in gall induction.  相似文献   

19.
A percutaneous method was used to remove stones from otherwise normal gall bladders, as assessed by cholecystography and ultrasonography. The procedure was performed in a single stage under general anaesthesia, adopting the method and instruments used for one stage percutaneous nephrolithotomy. A Foley catheter was left in the gall bladder and the system checked with contrast at 10 days to ensure free drainage and exclude residual calculi. Seven out of eight patients had a successful percutaneous cholecystolithotomy. An adequate track could not be secured in one man; he had an uneventful cholecystectomy under the same anaesthetic. Follow up at three months of the seven patients showed no calculi and no complications.Percutaneous cholecystolithotomy may prove complementary to extracorporeal shockwave lithotripsy in patients in whom there is difficulty focusing the shock waves on the gall bladder or who have had incomplete disintegration of stones.  相似文献   

20.
A case control study of gall stone disease in relation to diet, alcohol, and relative weight was undertaken. The study population comprised 267 hospital patients with newly diagnosed gall stone disease, 241 individually matched controls selected from the community, and 359 controls who were patients in hospital. Dietary intake was estimated with a quantitative food frequency questionnaire. Multiple logistic regression analysis was used to estimate the net association between individual nutrients and the risk of formation of gall stones. Variations in risk with sex and age were examined in the light of prior evidence of influences of sex hormones and age on hepatobiliary metabolism. In both sexes increased intake of alcohol was associated with a decreased risk of developing gall stones; increased intake of simple sugars in drinks and sweets was associated with an increased risk; and increased intake of energy or fat was associated with an increased risk in young subjects. Obesity was associated with an increased risk only in young women.  相似文献   

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