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1.
In order to evaluate the influence of thyroxine treatment on thyroid volume after thyroidectomy for non-toxic goitre 110 consecutive patients were randomised to receive thyroxine (150 micrograms daily) or no treatment three months after operation. Thyroid volume determined by ultrasonography did not differ significantly between the two groups one year after operation. Nevertheless, a similar decrease in volume was seen from three to 12 months postoperatively in the thyroxine treated and no treatment groups (median 18 (range 8-70) ml to 16 (range 7-57) ml, and median 20 (range 9-72) ml to 17 (range 8-58) ml, respectively). Three patients (two given thyroxine) had recurrence of goitre within the observation period of one year. In this series thyroid volume decreased during the first postoperative year independently of thyroxine treatment. Hence it seems questionable whether postoperative thyroid function studies can identify patients at risk of recurrence of goitre after operation for non-toxic goitre and whether routine postoperative treatment with thyroxine is justifiable.  相似文献   

2.
Iodine is considered an essential trace element for mammals, and its deficiency is related to numerous pathologies as severe as goitre, reproductive failure, mental retardation and brain damage, among others. Currently, about 30% of the world's population are affected by this deficiency, and thus, in an attempt to ameliorate these nutritional disorders, we propose a biofortification programme with iodine by an application of different dosages and forms of this element (iodide versus iodate) in lettuce plants. In this work, a study has been made of the iodine concentration in roots and edible leaves and their influence on nutritional quality through an analysis of its antioxidant capacity. The results showed that the most appropriate application rates in hydroponic cultivation were 40 μM or lower in the form I because these concentrations did not reduce biomass in the treated plants with respect to control plants and caused a foliar accumulation of this element that guarantees the viability of this type of programmes. Furthermore, these data are novel, given that the treated plants show a significant increase in antioxidant compounds after the application of iodine.  相似文献   

3.
Standard textbooks discuss parasitic disease according to specific organisms. In contrast, patients with parasitic infections present to physicians with a variety of clinical manifestations that may involve any of several organ systems and that often mimic nonparasitic diseases. A syndromic approach to the clinical situation may help the physician in considering the most important parasitic agents. Many parasitic infections can be acquired in temperate climates. While often considered tropical or exotic, other parasitic diseases are now seen more frequently in developed countries because of immigration and increased world travel. In this review the clinical syndromes associated with common parasitic diseases in North America are discussed, with an emphasis on risk factors and diagnosis of specific infections.  相似文献   

4.
Iodine deficiency is a major public health problem in developing countries. The main areas where goitre is prevalent have been identified, but the different degrees of severity and the populations affected have not. Most countries are now attempting to obtain reliable and more extensive data. A pilot study was carried out in the Ivory Coast in order to improve epidemiological knowledge of iodine deficiency and collect the information required to set up an elimination programme. The aim of this study was to assess the prevalence of goitre and cretinism and to measure the main biochemical indicators of thyroid function (T3, T4 and TSH). The study involved 1433 people identified from a census. The prevalence of goitre was 50.3%. There was a significant difference between the examined ethnic groups: 52.7% of the Yacouba and 28.6% of the non-Yacouba had goitre. The most affected age group was 15-45 year. The predominance of women demonstrated the susceptibility of women at child-bearing age to develop the condition. The prevalence of cretinism was approximately 1.5%. Through the assessment carried out using a grid of clinical indicators, it was possible to identify 10 cases of laboratory proven myxedematous cretinism due to hypothyroidism. The concentration of iodine in foodstuffs was below the limit of detection (< 7.5 micrograms/kg) and iodine could not be detected in the water (< 1 microgram.l) The biological profile of the population was affected to a very limited extent, with a mean value (+/- standard deviation) for TSH of 1.93 (+/- 1.56) mIU/l (0.1-4.0) and a free T4 value of 10 (+/- 3.46) pmol/l (8.2-20). These initial results confirm the high prevalence of endemic goitre and the low iodine content of the soil, water and food in the investigated region. The study will be complemented by a nutritional investigation to improve the understanding of iodine balance, after which an appropriate action plan will be proposed.  相似文献   

5.
The prevalence of endemic cretinism was measured in a village belonging to the Bwa ethnic group in Mali liable to iodine deficiency and suffering from endemic goitre. In this village according to mental and motor handicaps found in cretinism, we used two psychometric tests: the Raven's Progressive Matrice (PM 47) and a "peg test". Using the fiduciary inference method on the two tests associated with a clinical and qualitative approach, we obtained a prevalence of myxedematous cretinism close to 1.2%.  相似文献   

6.
A putative "entomoparasitic adult form" of Bursaphelenchus luxuriosae was found in the tracheal system and body cavity of its cerambycid vector beetle, Acalolepta luxuriosa. Morphologically, this form is intermediate between the usual mycophagous adult and the phoretic dauer juvenile, i.e., it shares the primary and secondary reproductive features with the mycophagous phase but shares a degenerate digestive tract with JIV dauer juveniles. In addition, the "parasitic form" has specialized characters relative to the mycophagous phase analogous to dicyclic Hexatylina, e.g., vacuole-like dots (assumed to be sensory organs) at the anterior end, a very long vulval flap, conical female tail, and elongated male spicules. The presence of insect-parasitic juveniles has been reported in several Bursaphelenchus species, but this is the first confirmed report of a putative "entomoparasitic adult form" in the genus. Thus, the "parasitic adult form" of B. luxuriosae is hypothesized to be an autapomorphic character of this species in the genus. The physiological impact of the parasitism on the host beetle is assumed to be weak because no clear symptoms were observed in the infested beetles. Also, no nematode eggs or propagative juveniles were observed in the beetle host, suggesting that more research is needed to confirm the nature of the association (parasitic vs. endophoretic).  相似文献   

7.
随着宠物饲养的盛行,与宠物相关的人兽共患寄生虫病愈加得到高度重视。为了避免和减少人兽共患寄生虫病的流行,本文就几种重要的宠物人兽共患寄生虫病的流行情况、诊断及防治等作一介绍,以期提高认识,防患未然。  相似文献   

8.
Riehl C 《Current biology : CB》2010,20(20):1830-1833
How do cooperatively breeding groups resist invasion by parasitic "cheaters," which dump their eggs in the communal nest but provide no parental care [1,2]? Here I show that Greater Anis (Crotophaga major), Neotropical cuckoos that?nest in social groups containing several breeding females [3], use a simple rule based on the timing of laying to recognize and reject eggs laid by extragroup parasites. I experimentally confirmed that Greater Anis cannot recognize parasitic eggs based on the appearance of host egg phenotypes or on the number of eggs in the clutch. However, they can discriminate between freshly laid eggs and those that have already been incubated, and they accordingly eject asynchronous eggs. This mechanism is reliable in naturally parasitized nests, because group members typically lay their?eggs in tight synchrony, whereas the majority of parasitic eggs are laid several days later. Rejection of asynchronous eggs therefore provides a rare empirical example of a complex, group-level behavior that arises through relatively simple "rules of thumb" without requiring advanced cognitive mechanisms such as learning, counting, or individual recognition.  相似文献   

9.
In a population of moorhens (Gallinula chloropus), at least27% of netting females laid one or more eggs in a neighbor'snest Females laid parasitically under three conditions: 56%of parasitic eggs were from nesting females that preceded layinga dutch in their own nest by a parasitic laying bout, 19% werefrom females whose nests were depredated before clutch completionand that laid the following egg parasiticaDy, and 25% were froma small number of females without territories, "non-nesting"parasites, that each laid a series of parasitic eggs. Clutchsizes varied greatly between females, but nesting females eachlaid a consistent clutch size both within and between seasonsfor a given mate and territory. Nesting females that employeda dual strategy of brood parasitism and parental care producedextra eggs that they laid in the nests of neighbors before layinga dutch in their own nests. Two out of ten females whose dutchesI experimentally removed during the laying period were successfullyinduced to lay their next egg in the nest of a neighbor. Nestingfemales that laid parasitically selected their hosts opportunisticallyfrom among the nests dosest to their territories. An experimentin which parasitic eggs were removed and hosts left to rearonly their own young showed that parasites did not choose hoststhat were better parents than pairs with contemporary neststhat were not parasitized. Females that only laid parasiticaDywithin a given season timed their parasitic laying bouts poorlyand achieved no reproductive success. Parasitic young rarelyfledged, and the mean seasonal reproductive success of nestingbrood parasites did not differ from that of nonparasitic females.However, the variance in reproductive success of nesting broodparasites was significantly higher than that of nonparasiticfemales.  相似文献   

10.
11.
The majority of reported pathologies in lissamphibians (salamanders, caecilians and frogs) include limb deformities such as missing limbs, multiple extra limbs and digits, or incomplete limb formation. However, comparatively little is known about congenital vertebral malformations or posttraumatic pathologies (e.g. injuries, infections) in the vertebral column of salamanders. In the present study, we describe eight vertebral deformities in three cleared and stained specimens of Desmognathus fuscus. Two specimens display developmental deformities which range from a potential non-segmented wedge vertebra to fully segmented hemivertebrae. The vertebral pathology in the third specimens possibly results from a parasitic infection. Apparently, these osseous deformities were not severe enough to prohibit survival of the specimens.  相似文献   

12.
The idea of parasitic systems, formulated by V.N. Beklemishev 70 years ago, represents a conceptual tool for the analysis of populational and biocoenotic roles of parasites. The questions concerning longterm stable persistence of host–parasite systems in communities can be discussed meaningfully only within this concept. Importantly, the set of terms elaborated within the parasitic system concept is applicable not only to parasitology, but also contributes to the general knowledge of life cycles of organisms and differences in the environment. This concept provides an opportunity for comprehensive analysis of systems, based on any type of stable biocoenotic interactions in the community (predation, commensalism, competition, etc.). Trematode-based parasitic systems, involving populations of intertidal mollusks of the genus Littorina, allow demonstrating how the strong “negative” effect of parasites on hosts at the individual level (complete parasitic castration) can be compensated at the population level. Such compensation functions as a prerequisite for maintaining long-term stable interactions between populations of parasites and their hosts within parasitic system (the ecosystem, biocoenotic level).  相似文献   

13.
Epidemiological investigations have shown that at the Bia?ystok Province about 30% of children and youth is afflicted with goitre. In this area drinking water is poor in iodine and iodine supply with food is quite unsatisfactory. The purpose of the present work has been to check the behaviour of the serum and urine iodine in children with thyroid goitre. The estimations of I in blood serum were made in 126 children with goitre (I, II, and III, according to the WHO classification) and in 100 healthy children. The method used included buthanol extraction according to Fisher and Morris. The concentration of iodine and its excretion rate in urine were assessed in 119 children with goitre of various advancement, an; in 170 children not affected with goitre, using the method of Fisher and Morris adopted to urine analysis. The authors found the following values for serum protein bound iodine: control group 4.9 microgram/100 ml, at average; 4.3 microgram/100 ml, 3.0 microgram/100 ml, and 2.6 microgram/100 ml in those affected with I, II, and III of the goitre, respectively. The 24 hr urine excretion rate of iodine in healthy children amounted to 66.4 microgram, and 64.2 microgram, 53.6 microgram, and 4o.2 microgram in those with I, II, and III goitre, respectively. The above results indicate a significant decrease of iodine concentration in blood serum and in urine in children with goitre; this decrease has been found to be dependent on the degree of the thyroid gland enlargement. The differences were statistically significant.  相似文献   

14.
Of 330 patients given lithium for recurrent manic-depressive disorder 12 developed goitre after treatment periods of five months to two years. All the patients remained clinically euthyroid. Pressure symptoms necessitated subtotal thyroidectomy in two patients. In 9 out of 10 patients with goitre, and in two out of seven without goitre study with radioactive iodine showed abnormal findings in iodine metabolism. Discontinuance of lithium led to disappearance of goitres, while thyroid metabolism returned to normal. Thyroxine or desiccated thyroid produced shrinkage of the gland in spite of continued lithium medication.  相似文献   

15.
Eriosoma aphids form leaf-roll galls on various elm species. Eriosoma yangi occurring on the Japanese elm is an obligatory "cuckoo" parasite, invading and usurping galls of other Eriosoma species. But another host race of E. yangi induces its own galls on the Chinese elm. Multivariate morphometries show that the two host races differ significantly in quantitative characters. Overwintering eggs of the parasitic form were experimentally transferred to the Chinese elm. The resultant larvae still exhibited a parasitic habit and developed into adults, which multivariate morphometries classified as the parasitic form. This form is considered different enough from the gall maker to be given a species rank. Eriosoma aphids facultatively invade other Eriosoma galls, where they sometimes deposit offspring. It is hypothesized that the parasitic form on the Japanese elm originated from a founder population which had migrated from the Chinese elm. On this new host, only those fundatrices that invade other species' galls will be able to leave offspring, because aphid fundatrices cannot gall plants other than their primary hosts. It is assumed that the parasitic form was established under intense selective pressure following a population bottleneck. This hypothesis was corroborated by field investigations at sites where the two forms occur sympatrically.  相似文献   

16.
Over the years, many attempts have been made to develop special stethoscopes for the teaching of auscultation. The objective of this article is to report on the experience with the development and implementation of an electronic stethoscope and a virtual library of cardiac sounds. There were four stages to this project: (1) the building of the prototype to acquire, filter and amplify the cardiac sounds, (2) the development of a software program to record, reproduce and visualize them, (3) the testing of the prototype in a clinical scenario, and (4) the development of an internet site, to store and display the sounds collected. The first two stages are now complete. The prototype underwent an initial evaluation in a clinical scenario within the Unit and during virtual out-patient clinical sessions. One hundred auscultations were recorded during these tests. They were reviewed and discussed on-line by a panel of experience cardiologists during the sessions. Although the sounds were considered "satisfactory" for diagnostic purposes by the cardiology team, they identified some qualitative differences in the electronic recorded auscultations, such as a higher pitch of the recorded sounds. Prospective clinical studies are now being conducted to further evaluate the interference of the electronic device in the physicians' capability to diagnose different cardiac conditions. An internet site (www.caduceusvirtual.com.br/ auscultaped) was developed to host these cardiac auscultations. It is set as a library of cardiac sounds, catalogued by pathologies and already contains examples from auscultations of the majority of common congenital heart lesions, such as septal defects and valvar lesions.  相似文献   

17.
We present a new fast approach for segmentation of thin branching structures, like vascular trees, based on Fast-Marching (FM) and Level Set (LS) methods. FM allows segmentation of tubular structures by inflating a "long balloon" from a user given single point. However, when the tubular shape is rather long, the front propagation may blow up through the boundary of the desired shape close to the starting point. Our contribution is focused on a method to propagate only the useful part of the front while freezing the rest of it. We demonstrate its ability to segment quickly and accurately tubular and tree-like structures. We also develop a useful stopping criterion for the causal front propagation. We finally derive an efficient algorithm for extracting an underlying 1D skeleton of the branching objects, with minimal path techniques. Each branch being represented by its centerline, we automatically detect the bifurcations, leading to the "Minimal Tree" representation. This so-called "Minimal Tree" is very useful for visualization and quantification of the pathologies in our anatomical data sets. We illustrate our algorithms by applying it to several arteries datasets.  相似文献   

18.
The region of Grobnik, in the north west of Croatia, 15 km away from the Adriatic coast and 400 meters above the sea level, used to be known as a centre of endemic goitre. Iodine prophylaxis of 10 mg KJ added per kilo salt started in Croatia during the year 1953 and it was increased to 25 mg KJ per kilo in 1996. During 1961, the prevalence of goitre among Grobnik school children was 63%, while in the adult population it was 34%. In 1981, 18% of goitrous school children and 11% of goitrous adults were found in the same region, which shows the fall in goitre prevalence in the twenty-year period, from a severe to a mild one. The aim of this study was to estimate the effectiveness of iodine prophylaxis in goitre eradication and to compare the obtained results to those found in the same region 20 and 40 years ago, namely, in 1961 and 1981. The research was conducted in 2001. We examined 472 Grobnik inhabitants, 378 children (196 girls and 182 boys, aged 7-15 years) and 94 adults. Regarding their size thyroid glands were graded according to WHO and PAHO classification. Data regarding lifestyles and health conditions were collected by individual and family questionnaires. The prevalence of goitre in 2001 was 6.6% in school children and 6.4% in adults. In relation to 1981, we found a statistically significant fall of goitre in school children at the level of p < 0.01 (chi2 = 23.65), but the prevalence change was not statistically significant in adults (p > 0.01, chi2 = 1.419). The frequency of thyroid gland hereditary diseases in native inhabitants was high, 11.7%. There were no statistically significant differences in the prevalence of goitre or thyroid hereditary diseases between groups of native and newcomers' children. According to our results, in the year 2001 the area of Grobnik was still was a region of a mildly expressed endemic goitre. This study presents final results of a 40-year long follow up of endemic goitre eradication, demonstrating the long-term effectiveness of iodine prophylaxis.  相似文献   

19.
The aim of the study was to examine whether evaluation of anisokaryosis is helpful in the cytological diagnosis of focal lesions in non-toxic recurrent goitre (NRG) after thyroidectomy for non-malignant goitre. Karyometric analysis was performed in routine cytological smears obtained from 80 females: 40 with focal lesions in non-toxic primary goitre (NPG) and 40 with NRG (postoperative histopathological examination revealed nodular goitre in both groups in all cases). We found that the level of anisokaryosis was significantly (P<0.005) higher in NRG than in NPG. There were no significant differences between the two lesions, in cellular composition or thyroid follicular cell arrangement. Thus, isolated anisokaryosis, a feature of malignancy in patients without a prior thyroidectomy, has limited diagnostic value in recurrent goitre.  相似文献   

20.
Mice fed a diet containing 1% (w/w) 3-hydroxy-4(1H)-pyridone (DHP) developed goitre even with a diet high in iodine whereas mimosine (0.5% w/w) did not produce goitre even with a low-iodine diet. Thyroid enlargement was apparent (measured morphometrically) by the 7th week and was advanced by the 11th week. Histologically the goitre was hyperplastic in type. No marked histological changes were found in other organs of mice fed DHP or any organs of mice fed mimosine, except for some atrophy of hair follicles. A single intragastric dose of DHP inhibited the uptake of 125I by the thyroid in the rat but an equivalent dose of mimosine did not. Evidence is presented that the inhibition occurs at the iodine binding step, as with methyl thiouracil, rather than at the iodide trapping step, as with thiocyanate. Chronic treatment of mice with DHP, as with 6-methyl thiouracil, increased the avidity of the thyroid in taking up 125I. The major conjugated form of DHP in mammals, DHP-3-O-glucuronide, was almost as effective a goitrogen as the unconjugated compound when given by mouth but considerably less active than the free form in the blood stream. It was concluded that DHP is a potent antithyroid compound of the thiouracil type with low general toxicity, since mammals can tolerate a level of intake sufficient to produce goitre in spite of iodine supplementation.  相似文献   

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