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1.
Geographic and seasonal variations in births   总被引:1,自引:0,他引:1  
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2.
A group of diabetic patients was submitted to a capillaroscopic examination at the level of the peri-ungual vallum and to a fluoroangiographic examination of the retina, for the evaluation of possible correlations between vessel conditions in to various districts. The Authors remarked that the subjects affected by proliferative diabetic retinopathy presented a greater dilatation of the ansae at cutaneous level, with haemorrhagic extravasations in 70% of the cases. On the contrary, on the subjects with nonproliferative diabetic retinopathy numerous aneurysmal "buttons" were noted at cutaneous level, both apically and laterally along the vascular ansa.  相似文献   

3.
Plasma levels of alpha-tocopherol, beta-carotene, total lipid, total cholesterol, beta-lipoproteins, and triglyceride were measured in healthy italian male adults of various age groups. Alpha-tocopherol mean values varied from 0.96 mg/100 ml in the subjects of 18-24 years to 1,14 mg/100 ml in the subjects of 25-64 years and to 1,08 mg/100 ml in those above 55 years. No value lower than the generally accepted minimum of 0,5 mg/100 ml was found. Correlation coefficients of all the variables were also studied. Alpha-tocopherol was shown to be significantly related to age and plasma cholesterol. These data agree with other authors' results.  相似文献   

4.
In 20 cases of Turner's syndrome (10 with complete X monosomy, 10 with partial X monosomy or mosaicism) aged 3.47 to 15.5 years, the stature of the individual cases and their parents were evaluated. A significant frequency of short stature in mothers (25% below--2.0 S.D.S) has been observed, with a significant difference compared to the mean female stature of the general population. No significant difference has been observed on the stature of fathers. There was a closer correlation with mother's height (r = 0.65, p = 0.001) than with father's height (p = 0.07).  相似文献   

5.
Summary The element concentration of moult feathers of White-tailed Eagles was investigated. Using the 2- MeV Hamburg proton microprobe we tried to differentiate between elements incorporated into the feather via the food chain and those which are deposited externally onto the feather vane. Regarding incorporated elements, special attention has been given to a possible correlation between element concentration and feather pigmentation. Concerning the elements detected in this work (S, K, Ca, Ti, Mn, Fe, Cu, Zn, Hg, Pb), calcium, manganese and zinc show a considerable enhancement within the pigmented feather as compared with pigment-free feather sections. On the other hand, no differences were found in concentrations for sulfur, titanium, iron, copper, mercury and lead. Our findings therefore imply a special enrichment of Ca, Mn and Zn within melanin, the source of the feather's pigmentation. The possible role of these elements with regard to melanin formation is discussed.
Melaninpigmentation und Elementkonzentration in Federn des Seeadlers (Haliaeetus albicilla)
Zusammenfassung Es wurden die Elementkonzentrationen in Mauserfedern von Seeadlern untersucht. Mit Hilfe der Hamburger 2-MeV-Protonenmikrosonde, die die Analyse von Probendetails im Mikrometerbereich ermöglicht, versuchen wir zwischen Elementen zu unterscheiden, die vom Adler mit der Nahrung inkorporiert, verstoffwechselt und während der Mauser in die Feder eingelagert wurden und solchen, die während der etwa einjährigen Verweilzeit der Feder im Gefieder extern aus der Atmosphäre aufgelagert wurden.Im Hinblick auf die eingelagerten Elemente untersuchen wir mögliche Zusammenhänge zwischen der Elementkonzentration und der Federpigmentierung. Von den nachgewiesenen Elementen (Schwefel, Kalium, Calcium, Titan, Mangan, Eisen, Kupfer, Zink, Quecksilber und Blei) zeigen Calcium, Mangan und Zink eine erhebliche Anreicherung in der pigmentierten Feder im Vergleich zu pigmentfreien Federausschnitten. Dagegen wurden keine signifikanten Unterschiede der Elementkonzentrationen von Schwefel, Titan, Eisen, Kupfer, Quecksilber und Blei festgestellt. Die gefundenen Ergebnisse bedeuten eine erhebliche Anreicherung von Calcium, Mangan und Zink im Melanin, das für die Federpigmentierung verantwortlich ist. Die mögliche Funktion dieser Elemente im Hinblick auf die Melaninbildung wird diskutiert.
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6.
In this study, we evaluate the clinical, histopathological and ultra structural aspects of the infection by field strain (MEL+) and mutated strain (MEL?) of Sporothrix schenckii. The development of sporotrichosis at the inoculation sites was similar for both groups of animals after the second week of the experimental period. Statistical differences appeared only at weeks 3 and 5. The pigmented isolate had greater tissue invasive capacity, promoting the formation of multifocal granulomas, whereas the albino isolate induced an enhanced inflammatory response, restraining the agent to the core of the granulomas.  相似文献   

7.
Summary The livers of Xenopus laevis, grouped by chronological age (0.5,2 and 3 yrs), were studied electron microscopically. Ultrastructurally most of the melanin granules in the mature female liver showed an-internal structure similar to the melanin granules of the oocytes. The hepatic melanin granules of immature females and of all males were pleomorphic and failed to show the characteristic internal structure similar to those of the oocytes. The oocyte is the probable source of most of the hepatic melanin of the mature female.  相似文献   

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陈小麟 《生态学报》2000,20(6):977-981
研究干旱地区蛛形纲动物的含能值变动规律。菜纲蝎目和蜘蛛目动物含能值之间的差异不显著,平均能值为21.32J/mg无灰干重。但是蝎目钳蝎科(22.13J/mg无灰干重)、蜘蛛目的圆蛛科(22.82J/mg无灰干重)、巨眼蛛科(22.65J/mg无灰干重)、跳蛛科(23.08J/mg无灰干重)和狼蛛科(21.76J/mg无灰干重)的含能值显著地高于蟹蛛科(19.04J/mg无灰干重)和盗蛛科(19.6  相似文献   

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Socioeconomic and seasonal variations in births: a replication   总被引:1,自引:0,他引:1  
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13.
Many studies, but not all, suggest that immigrant health worsens with duration of residence in the United States. Cohort effects may explain the inconsistent findings; not only are cohort effects confounded with duration, but the timing of entry into the United States may also create qualitatively different migration experiences. The present study tests for duration and cohort patterns among Asian immigrants to the United States across six year-of-entry cohorts (pre-1980, 1981–85, 1986–90, 1991–95, 1996–2000, 2001–05). Data come from the Asian American sample (n = 44,002) of the 1994–2009 waves of the National Health Interview Survey. The data show cohort differences for self-rated health, such that more recent cohorts showed improved baseline health compared to older cohorts. After accounting for cohorts, there was no significant change in self-rated health by duration of residence. Older cohorts actually showed improving self-rated health with longer duration. Obesity showed the opposite pattern; there were no differences across cohorts, but duration in the United States correlated with higher obesity. These results imply that immigrant health is not simply an issue of duration and adaptation; instead, they underscore the utility of considering cohorts as broader contexts of migration. Collectively, the results encourage future research that more carefully examines the etiological mechanisms that drive immigrant health.  相似文献   

14.
This study was conducted to test the hypothesis that spatial variations in soil microbial variables in a Thai rice paddy are accurately described by multivariate profiles of the soil bacterial communities. We found that community-level physiological profiles of soil bacterial communities could better describe the population density of Rhizoctonia solani in soil than the physicochemical profiles do. However, soil dehydrogenase levels were closely correlated with soil fertility (P<0.05), and these were better described by the physicochemical profiles. Hence, the hypothesis was rejected, and we suspect that soil microbial variables react differently to the same physicochemical changes. The average population density of R. solani (35 colony-forming units/g dry soil) was relatively high in the soil we studied, and the soil fertility was found to be among the poorest in Thailand. The soil quality was comparable to the most degraded bare ground soil in an adjacent bioreserve in terms of Shannon diversity index based on the communitylevel physiological profile as well as values of soil fertility indices. Overall, the soil microbial and physicochemical indicators showed that the paddy soil needs to be supplemented with soil nutrients. Otherwise, R. solani may cause a significant reduction in rice production.  相似文献   

15.
Five cases with different abnormalities of chromosome 18 are described: one case with trisomy 18, two cases with ring 18, one case with partial trisomy 18q and one case with a mosaic 18p-/iso 18q. The karyotypes of the parents were normal. Cytogenetic analysis was performed on PHA stimulated blood lymphocytes. GTG, QFQ, MTX banding techniques were used. Karyotype-phenotype correlations are made. All patients present mental retardation, hypotonia and facial dismorphisms. The different degree of mental retardation and the clinical signs are in relation to the different size of deletions or trisomies of the short or long arm of chromosome 18. In the case with mosaicism 18p-/iso18q the phenotype is determined from the chromosomal abnormality more frequent in the cells (18p-).  相似文献   

16.
1. Collation of the data presented in the preceding papers (references 4,5) showed a significant correlation (r = 0.83; P < 0.001) between the molecular mass (and hence the extent of halosubstitution) of halogenated biphenyls and their rate of hydroxylation by hepatic microsomal monooxygenases.2. There was no relationship between the extent of polyortho halosubstitution of biphenyl and the rate of metabolism.3. A marginal correlation (r = 0.33; P < 0.001) was found when the number of adjacent unsubstituted meta-para positions were linked to the rate of metabolism of PCBs. This structural feature facilitates microsomal oxidation.4. The results support the proposal that PCBs with meta-para hydrogen atoms are less enriched in tissues of animals and humans as this structural feature favours their metabolism by P450 isoenzymes.  相似文献   

17.
Summary An annual cycle, based on the differences between the speed of locomotion around midday and in the evening, was found for earthworms,Lumbricus terrestris L., maintained in the laboratory under constant conditions of light and temperature, and studied during parts of 1965, 1966, 1967 and 1968. During each month, the worms were faster in the evening than at noon, but this difference varied in degree through the year (Fig. 1). In addition, during part of the year, the differences between midday and evening were much greater for a 15-day period which centered on full moon than for a block of 15 days centered on new moon. Therefore, seasonal changes in lunar correlations were also indicated. These rhythms have been compared with others of lunar and annual frequencies, and their possible biological significance has been discussed.
Zusammenfassung In den Jahren 1965 bis 1968 wurde das lokomotorische Verhalten von Regenwürmern (Lumbricus terrestris L.), die bei konstanter Beleuchtung und Temperatur unter Laboratoriumsbedingungen gehalten wurden, untersucht; und zwar wurde mittags (12.00 Uhr) und abends (19.00 Uhr) die Zeit gemessen, die die Tiere benötigen, um 10 cm zu kriechen. Die Auswertung der Versuche zeigte, daß die Würmer abends immer schneller waren als mittags. Die Differenz der beiden Kriechgeschwindigkeiten schwankte jahresperiodisch (Fig. 1). Außerdem ergaben sich Hinweise dafür, daß die Mondphase von Bedeutung ist: Im Frühjahr und im Winter war der Unterschied zwischen der mittäglichen und der abendlichen Kriechgeschwindigkeit in der Woche vor und nach Vollmond viel größer als in den beiden Wochen um Neumond. Die Rhythmen der Lokomotionsgeschwindigkeit werden mit anderen Jahres- und lunarperiodischen Erscheinungen verglichen; ihre mögliche biologische Bedeutung wird diskutiert.
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Biotropic effects of geomagnetic storms and their seasonal variations   总被引:1,自引:0,他引:1  
A substantial effect of geomagnetic storms on human health with a confidential probability P = 0.95 was revealed. The quantitative estimates of the biotropic effect are presented. For example, the frequency of occurrence of bursts exceeding the average number of hospitalized patients with mental and cardiovascular diseases during magnetic storms increases approximately 2 times compared with quiet periods (based on the data on 1983-84). The frequency of occurrence of myocardial infarction, angina pectoris, violation of cardial rhythm, acute violation of brain blood circulation during storms increases 2.1; 1.6; 1.6; 1.5 times, respectively compared with magnetically quiet periods (based on the data of 1992-96). A similarity of the seasonal distribution of the magnitude of the biotropic effect is revealed in the case of myocardial infarction and the number of magnetic storms: a maximum in the equinox and a minimum in summer.  相似文献   

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