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1.
Furosemide causes both diuretic and non-diuretic changes in renal function. We compared responses to intravenous furosemide 0.5 mg.kg-1 in 38 subjects (30 males, 8 females) aged 18 to 30 with those in 14 subjects (9 males, 5 females) aged 50 and over. There were no consistent differences attributable to gender. Older persons showed greater natriuresis (47 percent in males and 26 percent in females) but their increment in plasma renin activity was markedly reduced. The urinary excretion of thromboxane B2 was elevated in older subjects (58 +/- 10 vs. 30 +/- 4 ng/4 h, p less than 0.05 for males; 48 +/- 7 vs. 29 +/- 4 ng/4 hr, p less than 0.05 for females) while that of 6-keto prostaglandin F1 alpha was not different. While differences in the diuretic response to furosemide may be due to pharmacokinetic differences, the non-diuretic response differences may reflect age related changes in renal prostaglandin synthesis.  相似文献   

2.
For the first time the natural immune stratum to hemorrhagic fever with the renal syndrome (HFRS) among the population of all regions of Bashkiria, a large territory with the highest morbidity level in this infection in the USSR, was studied. 9,176 persons over 15 years of age were examined by radioimmune techniques. Analysis of the immune structure of the population revealed that the share of immune males was higher than that of immune females, but the difference was less than the difference between males and females among the registered HFRS patients. Among children immune persons were almost completely absent. The immune stratum increased rather slowly among persons under 40 years, and only from this age the considerable increase of the immune stratum was observed (up to 16.2%). High risk groups included persons of such professions as forestry workers, truck and tractor drivers, oil workers and prospectors, livestock breeders, builders. These data may be used for the formation of groups to be vaccinated against HFRS in foci with different degrees of activity. Before vaccination the correction of groups to be vaccinated in a given region should be carried out, taking into account the immune structure of the population and the specific features of the local landscape and economy.  相似文献   

3.
A total of 176 hospital patients with chronic hepatitis C (CHC), among them 110 males and 66 females, were examined. The spectrum of antibodies to four hepatitis C virus (HCV) proteins (core, NS3, NS4, NS5) and in 142 patients --IgM antibodies to HCV (anti-HCV IgM) were determined. In 92% of the CHC patients antibodies to core, NS3 and NS4 proteins were simultaneously detected. Differences in the detection of antibodies to HCV in males and females were not statistically reliable. In CHC patients aged up to 20 years anti-NS4 and anti-NS5 were less frequently detected. Among males of different age groups reliable differences in the detection rate of anti-NS5 were registered, while among females of different age groups no such differences were observed. With the increase of age these antibodies were detected somewhat more often. In females over 60 years anti-HCV IgM occurred more often than in males of the same age. The levels of alanine aminotransferase (ALT) were higher in persons with the presence of anti-NS5 and anti-HCV IgM than in persons with their absence. In all groups of CHC patients with biochemical activity and liver cirrhosis the detection rate of anti-HCV IgM was significantly higher than in patients with normal ALT activity. The antibody spectrum with the simultaneous absence of HCV IgM and anti-NS5, while found to contain antibodies to other HCV antigens, was registered significantly less frequently in patients with moderate and high CHC activity and the liver cirrhosis induced by HCV infection.  相似文献   

4.
Tryptophan, copper and zinc levels were determined in the hair of 300 healthy subjects divided by sex, age and hair colour. Sex influences tryptophan content in hair, the levels of this amino acid being higher in males than in females. Tryptophan is also higher in infancy (2-5 years) and in both males and females aging around 80 years and over. Hair colour also influences tryptophan levels, which increase from fair to black hair. Copper levels are similar in hair of both males and females, while those of zinc are higher in women. Age influences the distribution of these two metals in human hair. Copper contents in hair of males are higher at the age 20-40 years. In females, values decrease over the age of 60 years. Instead, zinc levels are higher between 20 and 60 years in males, and between 13 and 19 years in females. As regards hair colour, copper is slightly higher in black hair in males and in fair hair in females, and lower in white hair in both sexes. Zinc values appear to be higher in red and lower in white hair in males. In females they are higher in black hair.  相似文献   

5.
Methaemoglobin, carboxyhaemoglobin concentrations and some haematological parameters were studied in fifty tobacco snuff addicts (40 males and 10 females) in some villages of Anambra State, Nigeria. The aim was to investigate possible adverse effects of tobacco snuff in addicts in Igbos of Anambra State. Fifty apparently healthy persons (25 males and 25 females) who do not inhale snuff were used as controls. The age range of tests and control subjects was 25-65 years. The results showed no statistically significant difference when the tests group was compared with the control group. A comparison of the results on the basis of sex, age and period of exposure, showed no significant differences. Blood picture in test and control groups was normocytic and normochromic. The results suggest that tobacco snuff may not have any adverse effect on haemoglobin metabolism and erythropoiesis.  相似文献   

6.
The concentration of twelve elements—potassium, calcium, manganese, iron, cobalt, nickel, copper, zinc, arsenic, selenium, bromine, and rubidium—in anterior pituitaries from human subjects and rats was measured using Particle Induced X-ray Emission (PIXE). The human material included anterior pituitaries from 37 normal human subjects, 27 males and 10 females, all of whom died from traumatic lesions. Excluded from the investigations were persons with alcohol abuse, regular use of drugs, and babies younger than 1 year. For selenium, zinc, bromine, and to some extent copper, there was good correlation between the amounts found in anterior pituitaries from rats and human subjects. A significant difference between male and female rat pituitaries was observed for copper, iron, and rubidium, whereas for humans significant difference was only observed for manganese. Anterior pituitaries from human females contained generally more zinc than male glands, but the concentration of zinc in young males was higher than in females. The present study also indicates age related differences in the copper content in anterior pituitaries from human subjects, since pituitaries from humans between 15–45 years contained 25% more copper than those from younger or older persons. The opposite pattern was observed in males. For such elements as Cu, Fe, Mn, and Se, the content in the anterior pituitary from human subjects was 1.6–2 times that stated for other endocrine organs.  相似文献   

7.
The aim of the study was to assess the effect of skinfold thickness on median and peak frequency of mechanomyographic (MMG) signal in relation to subject's age, gender and force during voluntary contraction of elbow flexor and extensor muscles. Seventy-nine healthy subjects participated in the study: 22 young females (age 20.1+/-1.1 years), 22 young males (age 23.4+/-1.1 years), 17 elderly females (age 64.9+/-5.1 years), and 18 elderly males (age 67.4+/-6.2 years). Three identical MMG probes were used to record MMG signals from above the triceps brachii (TB), biceps brachii (BB), and brachioradialis (BR) muscles simultaneously with the force signal. The results showed that the tissue between the muscle and the skin surface has a major contribution to the median and a minor contribution to the peak MMG frequencies independent of subjects' age (with force having more than 2 folds a smaller effect). During antagonistic function of the main elbow flexors and extensors, there is a decreasing effect of skinfold thickness and an increasing effect of force on the MMG frequency, and the relative contribution of both factors to the MMG signal is age related, especially in the TB and BR muscles. The BR muscle differs from the TB and BB muscles in regard to the effects of skinfold thickness and force on the MMG frequency, as well as in the effect of age on the relationship between the MMG frequency and skinfold thickness and force. The effect of age on the relative contribution of skinfolds and force to MMG frequency is specific for muscle and its function. It was concluded that studies that report MMG frequency with different values of skinfold thickness cannot be easily compared, especially when maximally activated prime movers are tested. A use of force and skinfold thickness as covariates is recommended when an MMG frequency is analyzed in subjects differing in the skinfold thickness.  相似文献   

8.
Using the G-banding technique, we examined lymphocytes from 90 individuals (43 males and 47 females, median age 31 years) living in buildings constructed with radioactively contaminated rebars. Forty-five nonexposed control subjects (22 males and 23 females, median age 30 years), matched to the radiation-exposed individuals by sex and age, were selected for comparison. At least 500 metaphases were checked for each individual. All recognizable structural aberrations of chromosomes or chromatids were recorded. After adjusting for age and smoking status, both the percentage of cells with aberrant chromosomes (PCAC) and the number of aberrant chromosomes per 100 cells (NAC) were found to be significantly higher in the radiation-exposed females than in the control females (p < 0.05 for PCAC and NAC). This difference, however, was not observed in the comparison of radiation-exposed and control males. This suggests a possible interaction between sex and radiation exposure in their effects on chromosome aberrations.  相似文献   

9.
Autism spectrum traits exist on a continuum and are more common in males than in females, but the basis for this sex difference is unclear. To this end, the present study draws on the extreme male brain theory, investigating the relationship between sex difference and the default mode network (DMN), both known to be associated with autism spectrum traits. Resting-state functional magnetic resonance imaging (MRI) was carried out in 42 females (mean age ± standard deviation, 22.4 ± 4.2 years) and 43 males (mean age ± standard deviation, 23.8 ± 3.9 years) with typical development. Using a combination of different analyses (viz., independent component analysis (ICA), fractional amplitude of low-frequency fluctuation (fALFF), regional homogeneity (ReHo), and seed-based analyses), we examined sex differences in the DMN and the relationship to autism spectrum traits as measured by autism-spectrum quotient (AQ) scores. We found significant differences between female and male subjects in DMN brain regions, with seed-based analysis revealing a significant negative correlation between default-mode resting state functional connectivity of the anterior medial prefrontal cortex seed (aMPFC) and AQ scores in males. However, there were no relationships between DMN sex differences and autism spectrum traits in females. Our findings may provide important insight into the skewed balance of functional connectivity in males compared to females that could serve as a potential biomarker of the degree of autism spectrum traits in line with the extreme male brain theory.  相似文献   

10.
381 glucose intake normal curves were studied according to the Diabetes Data Group new classification in healthy persons between 10 and 80 years in order to assess the influence of the age upon the normal glucose tolerance. Such an influence, which was evident in all the subjects, turned out to be more important in women with respect to me. In fact, males showed an increase, per decade, of about 1 mg/dl in fasting glycemic levels, of about 6 mg/dl at 60', of 4 mg/dl at 120', while in females there was an increase of about 2 mg/dl in fasting glicemic values, of about 6 mg/dl at 60' and of about 5 mg/dl at 120'. No meaningful correlation between age and insulinemic values was found at all considered points, either in males or in females. The reasons of the decreased glucose tolerance with aging and of its different behavior in the two sexes are discussed.  相似文献   

11.
The cytokinesis-block micronucleus assay (CBMN) was used to assess the variability and determine possible influences of external and internal factors on the background levels of cytogenetic damage in peripheral blood lymphocytes (PBL) of 50 healthy volunteers selected at random from the general population of Croatia. The mean MN frequency for all subjects was 4.74+/-0.31 per 1000 cells and the mean cytokinesis-block proliferation index (CBPI) was 1.82+/-0.01. The mean frequency of nucleoplasmic bridges (NPB) for all subjects was 0.06+/-0.04 and of nuclear buds (NB) 0.12+/-0.05. The canonical correlation analyses indicate a positive non-significant correlation between the MN frequency and age, gender and smoking habits. Results of factor structure and canonical weights showed that age and gender rather than smoking habits control the incidence of MN in PBL of healthy volunteers. The lowest median value of MN was observed in subjects younger than 30 years (both smoking and non-smoking). Generally, non-smokers had lower median values of MN compared to smokers. In non-smokers, males showed lower micronucleus incidence than females. Within the non-smokers smaller differences in the median values of MN between subgroups (male and female; age subgroups) were observed. Among smokers, females had a two-fold higher median value of MN frequency than males, but this difference was not significant (p=0.2643, Mann-Whitney U test). Canonical correlation analyses indicate a strong and significant correlation between cell proliferation parameters (M1-M4 and CBPI) and age, gender and smoking habits. The most sensitive parameters were M3 and M4. Age had the strongest effect on M3, while M4 was highly influenced by smoking habits. Gender had an equal non-significant effect on both parameters. The usefulness of the new criteria for the cytokinesis-block MN assay measuring DNA damage as a sensitive biomarker in biomonitoring studies is confirmed.  相似文献   

12.
The thermal environment and length of the activity season are important factors in shaping life-history trait variation in ectotherms. Many ectothermic vertebrates living at high latitudes or altitudes tend to be larger and older than their conspecifics living at lower latitudes or altitudes. However, detailed data on age, body size and growth variation—and how they may differ between males and females—are still scarce, especially from extreme high-latitude environments. We studied growth (body length increment), age and size structure of common frogs (Rana temporaria) in subarctic Finland (69°04′N) by applying skeletochronological methods to individually marked adults (n?=?169) captured and recaptured between 1999 and 2003. We found that breeding males were on average younger (mean?=?8.5?years) than females (11.9?years) and that males started reproducing earlier (≥3–4?years of age) than females (>4–5?years). The oldest encountered individual was an 18-year-old female, which to our knowledge is the oldest wild common frog ever reported. Females were on average larger (mean body length?=?76.6?mm) than males (70.7?mm), and this appeared to be mainly due to their older age as compared to males. While body length increased and growth rate decreased with age in both sexes, growth rate declined significantly faster with age in males than in females. The latter finding provides a proximate explanation for the observation that even after accounting for age differences among sexes (females?>?males), females were longer than males.  相似文献   

13.
In the period February–May 1968 the reflectances of the exposed (forehead) and unexposed (inside upper arm) skin, were measured at nine wavelengths (430, 470, 490, 520, 550, 580, 600, 660 and 685 mμ), using an “EEL” Reflectance Spectrophotometer in 100 Dutch families. The reflectance curves of upper arm and forehead show the shape usually found in white persons. The skin colour of the upper arm is lighter than that of the forehead in males and females. A difference in skin colour between males and females is observed. The forehead reflectances of males are lower than of females, and the upper arm reflectances of females are lower than those of males. A similarly directed sex difference in skin colour at the forehead has been found in other white groups. If no difference in reaction on exposure exists between both sexes, then the skin colour of the male upper arm will be lighter than that of females, although males in general are more exposed to radiation, because male arms are less uncovered than female arms. No change in skin colour at the upper arm is observed during ageing. As judged from the wavelengths concerned the changes in skin colour at the forehead during ageing result for the greater part both from a regular accumulation of melanin, and an increase in the blood flow of the skin, particularly during the years 11–25.Intrafamilial reflectance resemblances are investigated by means of correlations computed from the upper arm reflectance values measured at wavelengths 550 and 685 mμ. Significant positive correlations between the parents, 0·299 (wavelength 550 mμ) and 0·226 (wavelength 685 mμ) respectively, indicate positive assortative mating. The pattern of intrafamilial correlation coefficients suggests a role of X-chromosomal genes in the causation of the variability in the reflectances measured at wavelength 685 mμ (a measure of melanin deposition). Intrafamilial correlation computations of reflectances measured at wavelength 550 mμ (a measure of vascular response) show some positive correlations, but the role of genes in the causation of the variability in these reflectances remains unclear.  相似文献   

14.
ICES has identified red gurnard Aspitrigla cuculus (L.) as a potential commercial species and recommended that monitoring programmes should be conducted to derive information on biological parameters for stock assessment purposes. In this paper, data on the population biology of red gurnard in the coastal waters of Northwest Wales and Eastern Anglesey are presented. Total length (TL) of fish sampled ranged from 15.4 to 35.0 cm (males) and 10.5 to 43.1 cm (females), with the majority of females between 20 and 30 cm TL (70.0%) and males between 20 and 30 cm TL (71.0%). TL/weight (W) relations were similar between immature and mature individuals for both sexes and between both sexes (all maturity stages combined), producing a combined data equation W = 0.005 TL3.19. Age of fish ranged from 1 to 7 years and 1 to 6 years, respectively, for females and males, with the majority of females age 3 (37%) and the majority of males age 2 (49%). The age structures of female and male red gurnards were significantly different, with the older age classes consisting predominantly of female fish. Both males and females exhibited similar asymptotic growth patterns; the combined von Bertalanffy growth function was . Instantaneous rates of total mortality were calculated as 1.13 year?1 for males and 0.98 year?1 for females. The size (L50) and age at first maturity (A50) were estimated to be 26.3 cm TL and 3.6 years for males, 28.1 cm TL and 3.5 years for females and 25.6 cm TL and 3.7 years for both sexes combined.  相似文献   

15.
Variation in age structure and body size benefits are identified to understand the evolution of life history. Here, we estimated the age structure and body size of two species of odorous frogs(Odorrana margaretae and Odorrana grahami) by using skeletochronology. The ages at sexual maturity of O. grahami and O. margaretae in both sexes were 1 and 2 years, respectively. For both sexes, the maximum age observed in O. margaretae was six years. For O. grahami, the maximum age observed in males and females were 4 and 5 years, respectively. Males and females did not differ in mean age in the two species.The average body size of both species considerably differed between sexes, with females being larger than males. The body size of females was also larger than that of males when the effect of age was removed. We also found positive correlations between body size and age within each sex in O. margaretae, but only for female in O. grahami. The female-biased sexual size dimorphism of the two species suggested that fecundity selection for larger female size may increase the reproductive output.  相似文献   

16.
Twelve young (4-7 years of age) and 14 old (20-27 years of age) male and female rhesus monkeys were tested on seven cognitive tasks. Males and females performed similarly on tasks of object memory and executive function, but young males outperformed young females on a spatial memory task (Delayed Recognition Span Test) that requires the identification of a new stimulus among an increasing array of serially presented stimuli. This superior level of spatial ability in young males declined sharply with age, so that old males did not perform significantly better than old females. These findings in the nonhuman primate suggest that biological rather than sociocultural factors underlie the sex differences in cognition and their diminution with age.  相似文献   

17.
This paper reports the blood lipid status of people aged 4 years and older in Taiwan. The data is based on the Nutrition and Health Survey in Taiwan (NAHSIT: 1993-1996), which adopted a multi-stage, stratified clustering sampling scheme. Altogether, 5097 subjects (2451 males and 2646 females) had data on triglyceride and 5643 subjects (2736 males and 2907 females) had data on cholesterol. We found that (a) cholesterol levels of males were lower than females in mid-to old age group (> or = 45 years old); (b) triglyceride values of females were lower than males in young adulthood (19-44 years), but higher than males after the age of 45 years, and (c) adult females had higher HDL-C value and lower ratio of total cholesterol to HDL-C than males. The prevalence of hypercholesterolemia was 10.2% in adult males and 12.6% in mid-to-old aged men, and that in females was 11.2% and 24.4%, respectively. The prevalence of hypertriglyceridemia was 13.4% and 6.1% in adult males and females (> or = 19 years as a whole), respectively. It was 12.3% in mid-to-old aged men (> or = 45 years), and 11.9% in women. The mean cholesterol values were similar to values of several previous surveys in different areas of Taiwan. But it was higher than those in some areas of Mainland China, and lower than those of western countries. People in metropolitan cities had a higher level of blood cholesterol than other areas. The average triglyceride values of males and females were higher than those of previous studies in Taiwan and of people in Mainland China. Mountainous stratum with predominantly aboriginal residents had higher level of triglycerides and body mass index (BMI) than other strata. The associations between dietary intakes of men and women and blood lipids were examined controlling for age and BMI. Result showed that Keys score, which was derived from saturated fat, polyunsaturated fat and dietary cholesterol of a 24-hour recall, was positively related to blood cholesterol and LDL-C in men, but not in women. Average alcohol intakes per day were related to HDL-C positively, but LDL-C negatively in men and women. The regional differences in blood lipid profiles in Taiwan are consistent with the dietary and life-style variations island-wide.  相似文献   

18.
Previous work showed that obesity in the average human male is not due to increased caloric intake. To test the hypothesis that 'social' ethanol consumption causes obesity by a hepatotoxic mechanism, the relationships between alcohol intake, cigarette smoking, serum gamma-glutamyl transpeptidase (GGT) and body build were investigated in 816 adult patients, 491 males and 325 females. A large part of the Broca index variance could be explained by hepatic damage as reflected by the GGT level. The higher the GGT, the more overweight were the subjects. Hyperinsulinemia may be the pathogenetic link; insulin is the strongest known blocker of lipolysis. Almost the total variation of obesity with GGT, however, occurred in the range of GGT up to 25 U/l, which is usually, but nevertheless erroneously, considered to be the normal range. This effect was independent of sex and age. Normal GGT is below 10 U/l, which is found on average in females aged less than 20 years. Females tolerate less alcohol than males. Although GGT is as high in females as in males around age 30, males drink about three times as much ethanol. For the same GGT the Broca index is significantly higher in females than in males. GGT generally increases with age; maximum GGT is reached in females in the age group 21-40 years (due to the change in drinking habits around 1968), declining thereafter; in males at age 50. Obesity per se is not correlated with a high GGT. In the females there are hormonal factors influencing obesity. Although in the females GGT decreases on average after age 40, obesity increases (due to the decrease in estrogens). After age 50 ethanol tolerance in males decreases: they reduce their alcohol consumption, and yet the GGT remains high. -Cigarette smoking is a factor which independently influences obesity. Although people who smoke tend also to drink more alcohol, smokers are significantly leaner than nonsmokers. On average males smoke about twice as heavily as females; this contributes to the fact that on average males are leaner than females despite their higher alcohol consumption. Due to lower consumption the influence of ethanol and smoking on body build is smaller in females than in males.  相似文献   

19.
Measurements of the curvature of the lumbar spine are useful in the investigations of low back pain. It is unclear whether the degree of lumbar lordosis, sacral inclination and lumbosacral angulation are the same for all normal adults. Radiographic studies were carried out on the lumbar spines of subjects aged 9-61 years. Mean and 95% tolerance ranges of the values of lumbar lordosis, lumbosacral angle and sacral inclination for adult age groups up to the sixth decade are given. The results showed that all three parameters varied steadily with age. The pattern of changes differed in males and females. Females had greater angles than males. Sacral inclination appeared to be a more important determinant of the degree of lumbar lordosis. All three parameters showed a tendency to decrease after the sixth decade. The significance of the findings is discussed.  相似文献   

20.
In 1999, we measured the body mass of 101 wild ring-tailed lemurs (Lemur catta) inhabiting the Berenty Reserve, Madagascar. In addition, we counted the number of ticks [Haemaphysalis (Rhipistoma) lemuris Hoogstraal, 1953] infesting their facial skin and external auditory meatuses. For both males and females, the body mass appeared to increase until the age of 3 years. With the apparent exception of infants, there were no sexual differences in body mass. Within a group, higher-ranked adult males tended to be heavier than lower-ranked males. In contrast, there was no consistent correlation between the body mass of females and their ranks. Among the study groups, there was a small difference in body mass and significant difference in the number of ticks infesting the facial skin and external auditory meatuses. In particular, lemurs of a group who inhabited an area of gallery forest in the study area exhibited the smallest values of body mass and were severely infested with ticks. Such group variations were not consistently correlated with the reproductive parameters of the study groups. In three groups moderately infested with ticks, ticks infested adult males and subadults more heavily than adult females, juveniles, and infants.  相似文献   

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