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1.
Previous research has revealed that an emotional response to weather might be indicated by calls to telephone counseling services. We analyzed call frequency from such "hotlines", each serving communities in a major metropolitan area of the United States (Detroit, Washington DC, Dallas and Seattle). The periods examined were all, or parts of, the years 1997 and 1998. Associations with subjectively derived synoptic weather types for all cities except Seattle, as well as with individual weather elements [cloudiness (sky cover), precipitation, windspeed, and interdiurnal temperature change] for all four cities, were investigated. Analysis of variance and t-tests (significance of means) were applied to test the statistical significance of differences. Although statistically significant results were obtained in scattered instances, the total number was within that expected by chance, and there was little in the way of consistency to these associations. One clear exception was the increased call frequency during destructive (severe) weather, when there is obvious concern about the damage done by it.  相似文献   

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Temperature and precipitation have been identified as factors that potentially influence eastern wild turkey (Meleagris gallopavo silvestris) reproduction, but robust analyses testing the relationship between weather parameters and turkey nest success are lacking. Therefore, we assessed how weather influenced turkey daily nest survival using 8 years of data collected from 715 nests across the southeastern United States. We also conducted exploratory analyses investigating if weather conditions during or prior to nesting best predicted nest success. We then assessed the possible implications of climate change through 2041–2060 for future eastern wild turkey daily nest survival and nest success for variables determined significant in analyses. During incubation, positive anomalies of minimum daily temperature were associated with greater daily nest survival. Precipitation during nesting was not a good predictor of daily nest survival. Exploratory analyses unexpectedly indicated that weather conditions in January prior to incubation were more important to nest success than weather conditions during incubation. In January, negative anomalies of minimum temperature and greater average daily precipitation were associated with greater nest success. Projections of future nest success or daily nest survival based on these relationships with the predictive covariates, and informed by climate models, suggest that nest success may increase as January precipitation increases and that daily nest survival may increase as temperature during incubation increases. These positive associations could be offset by a negative association between nest success and the expected increases in January minimum average temperature. Additional research is needed to investigate causes of these relationships and assess the implications of climate change for eastern wild turkey poult survival.  相似文献   

4.
Yang AC  Fuh JL  Huang NE  Shia BC  Peng CK  Wang SJ 《PloS one》2011,6(1):e14612

Background

Patients frequently report that weather changes trigger headache or worsen existing headache symptoms. Recently, the method of empirical mode decomposition (EMD) has been used to delineate temporal relationships in certain diseases, and we applied this technique to identify intrinsic weather components associated with headache incidence data derived from a large-scale epidemiological survey of headache in the Greater Taipei area.

Methodology/Principal Findings

The study sample consisted of 52 randomly selected headache patients. The weather time-series parameters were detrended by the EMD method into a set of embedded oscillatory components, i.e. intrinsic mode functions (IMFs). Multiple linear regression models with forward stepwise methods were used to analyze the temporal associations between weather and headaches. We found no associations between the raw time series of weather variables and headache incidence. For decomposed intrinsic weather IMFs, temperature, sunshine duration, humidity, pressure, and maximal wind speed were associated with headache incidence during the cold period, whereas only maximal wind speed was associated during the warm period. In analyses examining all significant weather variables, IMFs derived from temperature and sunshine duration data accounted for up to 33.3% of the variance in headache incidence during the cold period. The association of headache incidence and weather IMFs in the cold period coincided with the cold fronts.

Conclusions/Significance

Using EMD analysis, we found a significant association between headache and intrinsic weather components, which was not detected by direct comparisons of raw weather data. Contributing weather parameters may vary in different geographic regions and different seasons.  相似文献   

5.
The endocrine regulation of parturition exhibits several interspecies differences. Among the endocrine parameters considered to be the most important ones from the point of view of the regulation of parturition the concentration of oestrogens (oestradiol, oestriol and oestrone), progesterone, PGF2 alfa and its degradation product PGFM, was determined in both peripheral and uterine venous blood by RIA method in rats starting from the 15th day of pregnancy to the 3rd or 4th day following parturition. In the pregnant rat oestriol could only be detected on the day of parturition (21th day). Concentrations of oestriol and oestradiol were the highest on the day of parturition. An opposite tendency could be observed as far as progesterone concentration was concerned, i.e., the concentration decreased gradually from the 15th day of pregnancy onwards and the lowest value was reached on the day of parturition both in peripheral and uterine venous blood. PGF2 alfa and PGFM concentrations in the uterine vein increased gradually from the 15th day of pregnancy and the highest value could be detected peri partum. Our data, in accordance with those of others support the idea that the hormones investigated are involved in the process of parturition, i.e., characteristic changes of oestrogens, progesterone and prostaglandin levels ensue in the rat prior to parturition.  相似文献   

6.
The purpose of this paper was to impair normal parturition in rats in order to measure tissue levels of progestins and estrogens and compare these results with those of normal parturition in rats. Abnormal parturition was obtained by injection of isotonic saline into the uterine lumen of pregnant rats at the end of pregnancy or by handling the uterus. After each of these treatments on day 21 of pregnancy, parturition was impaired in 70 to 98% of the rats. When the treatments were carried out earlier or later in pregnancy, there was little or no impairment. Our results indicate transient discrepancies in plasma and tissue levels of steroids 6 h after treatment on day 21: 20 alpha-HP concentrations increased in treated rats compared to controls (uteri: 470%; p less than 0.01; ovaries: 89%; p less than 0.001); concomitantly, there was a sharp rise in P concentrations in uteri (+ 74% : p less than 0.05) and ovaries (+ 52%; p less than 0.05). Inversely, uterine concentrations of E2 decreased 6 h after treatment compared to controls (- 30%; p less than 0.05), although there was a transient rise of E2 in the ovaries (+ 30%; p less than 0.05). Twenty-four hours later, E2 concentrations were always lower in the uteri (- 30%; p less than 0.01). No change in E2 levels was noted in the uteri or ovaries of either the control or treated rats. The physiological significance of these changes and their consequences on uterine reactivity at term have been discussed. The data demonstrate that day 21 was a critical period in the parturient activity of the rat uterus which appears to be primarily affected by uterine levels of E2 between days 21 and 22 of pregnancy.  相似文献   

7.
Pits, cavities and depressions located on the dorsal surface of the pubic symphysis of females have been attributed to the trauma of parturition. Earlier research based on human skeletal remains provides inadequate information on the individual's obstetrical history. The 68 female pubic bones that were studied had comprehensive medical records indicating whether or not each female had given birth. Fourteen and one-half percent of the females who had not given birth exhibited trace to small scarring of the pubic symphysis and 23.4% of the females who had not given birth exhibited medium to large scarring. It is suggested that bony changes previously used as an indicator of child bearing must be re-examined in light of the fact that “birth scarring” has been found in women known not to have had children.  相似文献   

8.
Sow responsiveness towards external disturbances and concurrent postural changes are proposed to be an important cause of early piglet crushing. The aim of the present study was to assess whether loose housed sows change their responsiveness over time within the first 24 h after birth of the first piglet upon exposure to different types of human contact and towards piglets’ scream. The responsiveness of the sows (n = 17) was scored during: (i) blood sampling of the sow during 24 h after the onset of parturition, (ii) human handling of a piglet at 0, 30 min, 1, 2, 4, 8 and 24 h after birth, (iii) screaming when a piglet was trapped underneath the sow and (iv) exposure to playback of piglets’ screams at 10 and 24 h after the onset of parturition. A sow was scored as responsive if she changed her posture in response to the stimuli. The behavioral scores were analyzed during three predefined periods: parturition (from birth of first piglet to birth of last piglet), phase 1 (from birth of last piglet to 12 h after birth of first piglet) and phase 2 (from 12 h after birth of first piglet to 24 h after birth of first piglet). The responsiveness of sows towards humans during blood sampling differed between the three periods (p < 0.01), whereas it did not differ between periods during human handling of piglets. During blood sampling, fewer sows were responsive during phase 1 (5%) compared to during parturition (11%) and the later phase 2 (17%). We did not detect any temporal changes in sow responsiveness towards natural incidences of screaming of own trapped piglet between the three periods (it remained high: 80%), whereas sows exposed to playback of piglet screams had a higher probability (p < 0.05) to react at 12 h (50%) than at 24 h (25%). In conclusion, the responsiveness of sows toward direct human contact was lower during the first 12 h postpartum. The careful handling of piglets in the home pen had a minimal effect on the probability of postural changes in sows. However, sows were highly reactive towards the screaming of own trapped piglet during the whole 24 h period pp. The relative lower responsiveness towards playbacks, decreasing from 12 to 24 h pp, cast doubt upon the piglet scream playback test as a useful approach to evaluate maternal responsiveness in sows.  相似文献   

9.
Recent analysis of mice deficient in both oxytocin (OT) and cyclooxygenase-1 has shown that OT exerts significant effects on both the ovarian corpus luteum and the uterine myometrium during pregnancy. To better define the roles of OT during pregnancy, we evaluated OT action and OT receptor regulation in wild-type and OT-deficient knockout (KO) mice. Continuous infusion of OT revealed that OT can either delay labor at low doses or initiate preterm labor at high doses. The infusion rates of OT necessary for these effects were reduced in OT KO mice. The dose of OT that delayed labor also delayed the normal decrease in plasma progesterone late in gestation, implicating a primary effect on the corpus luteum. Consistent with this hypothesis, luteal OT receptor expression exceeded that of the myometrium until luteolysis occurred. We propose that the downregulation of OT receptors in the corpus luteum and induction of OT receptors in the myometrium serve to shift the predominant consequence of OT action during murine pregnancy from labor inhibition to labor promotion.  相似文献   

10.
Human amnion, chorion, decidua and placenta produced 6-oxo-PGF when superfused . Furthermore amnion, an avascular tissue, produced more 6-oxo-PGF after labour than all other tissues investigated and its production of 6-oxo-PGF was significantly greater after labour than before the onset of labour. These findings suggest that prostacyclin production by foetal membranes may have a role in the mechanisms controlling human parturition. Moreover, this is the first evidence for the production of prostacyclin by an avascular tissue.  相似文献   

11.
Polymorphic bands were detected within the DQB and DRB regions of the ovine major histocompatibility complex by probing TaqI digested DNA from three large sheep half-sib families derived from a highly resistant ram. All animals were phenotypically assessed for Haemonchus contortus resistance by faecal egg counts and associations with RFLP bands and haplotypes were estimated using mixed model, best linear unbiased prediction statistical methods. Although the highly resistant sire was homozygous at the MHC, no significant associations were found between any band or haplotype and faecal egg count.  相似文献   

12.
13.
5-Hydroxyeicosatetraenoic acid (5-HETE) is an arachidonic acid (AA) metabolite derived from the lipoxygenase pathway which is capable of inducing uterine contractions. The purpose of this study was to determine a). whether 5-HETE concentrations in amniotic fluid increase before or after the onset of labor and b). whether acetylsalicylic acid (ASA) could modulate the production of 5-HETE by human amnion cells. 5-HETE concentrations are increased in amniotic fluid before the onset of labor. Furthermore, ASA treatment as expected inhibited PGE2, but also significantly increased 5-HETE production by amnion cells. 5-HETE concentrations on average increased by greater than 2.5 fold (p < 0.001) in amniotic fluid prior to spontaneous labor when compared with samples obtained from the same patients earlier in gestation and therefore may be important in mechanisms regulating the onset of labor. ASA provokes an increase in 5-HETE biosynthesis by amnion cells: control media 2.60 ± 1.5, ASA treatment alone 5.17 ± 0.20, IL-1β alone 6.39 ± 2.1, and ASA + IL-1β 8.95 ± 1.2 (mean ± SEM) picograms per microgram protein per 16 hours. These findings may explain in part why cyclooxygenase inhibitors are not always successful in treating women with preterm labor.  相似文献   

14.
A new argument that species are individuals has recently been presented based on the way species names are used and systemic logic. The alternate idea that species are a categorical item, i.e., collections of individuals, was rejected. We wanted to evaluate this approach by establishing concepts that apply to individuals in order to examine if they are also applicable to a species viewed as a categorical item. It is our thinking that if species are not such, then concepts applicable to individuals will not be applicable to species so viewed. Individuals and species are similar in the presence of conceptual boundaries, unidirectional change and the presence of past and future time. These are all central, and salient, biological phenomena. But, these are concepts that apply also to populations which, for the most part, are not the same as species. Thus, these considerations infer that species, when viewed as a collection of individuals, do not share relevant concepts with individuals. Our conclusion is that a species is a 'unity' rather than an 'individual'.  相似文献   

15.
Historical records (1900–66) from the Lepidoptera Recording Scheme were used to examine associations with weather for three butterfly species Ladoga Camilla, Celastrina argiolus and Nymphalis polychloros. For each species, a series of equations was examined in which the number of records per year was considered to be a function of (1) the number of records in the previous year and (2) temperature or rainfall in the months leading up to the current flight-period. Significant associations with weather were found for all species. Further multiple regression equations were obtained, using a stepwise procedure to select weather variables contributing separately to annual variation in the number of records. For L. Camilla and C. argiolus, predictions from these equations were significantly correlated with data on changes in abundance for the later period 1976–91. No recent data exist for JV. polychloros, which is now very rare, or possibly extinct, in Britain. Similar historic data are available for other butterfly species and for other taxa. It is suggested that these types of data have potential for the study, and perhaps prediction, of some effects of climate change.  相似文献   

16.
Human amnion, chorion, decidua and placenta produced 6-oxo-PGF1alpha when superfused in vitro. Furthermore amnion, an avascular tissue, produced more 6-oxo-PGF1alpha after labour than all other tissues investigated and its production of 6-oxo-PGF1alpha was significantly greater after labour than before the onset of labour. These findings suggest that prostacyclin production by foetal membranes may have a role in the mechanisms controlling human parturition. Moreover, this is the first evidence for the production of prostacyclin by an avascular tissue.  相似文献   

17.
Because of the very high activity and abundance of human red cell carbonic anhydrase C (carbamate hydrolase, EC 4.2.1.1), it seemed likely that the second isozyme, B, might not be essential for CO2 metabolism. It was then found that physiological concentrations of Cl- inhibited catalysis of CO2 hydration by the B enzyme (but not by type C), suggesting further that type B does not function in vivo as a carbonic anhydrase. The versatility of the catalytic activity of carbonic anhydrase for a number of 'artificial' substrates suggested that enzyme B may be utilized in reactions of intermediary metabolism. A number of hydration, dehydration, decarboxylation, kinase, and phosphatase systems were tested to determine a possible physiological function for the enzyme. Results with eighteen possible substrates were negative and the possibility is discussed that mammalian carbonic anhydrase B is an evolutionary accident.  相似文献   

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19.
The role of foetal adrenal DHAS in initiation of human parturition was studied by direct estimation of umbilical arterial blood samples and correlated with the oxytocin consumption during induced labour, Author found a closed relation between the above parameters and suggested that foetal adrenal activity might be involved in the initiation of human parturition.  相似文献   

20.
Cortical connectivity was studied in tasks of generating the use of words in comparison with reading aloud the same words. These tasks were used earlier in PET and high-density ERP recording studies, which described both the functional anatomy and time course of involvement of cortical areas in word processing. We developed a new method for studying the synchrony of EEG spectral components within the short time intervals compatible with the duration of particular cognitive operations. The wavelet transform of the ERP records and calculation of correlations between the wavelet curves were used to reveal connections between cortical areas. Three stages of intracortical communications developing over the course of task performance were discovered: between the right and left frontal areas (0-200 ms after the stimulus presentation), between the left frontal and left posterior temporo-parietal areas (250-500 ms), and, finally, between the left temporal and right fronto-centro-temporal areas. These findings are in good agreement with the results of the previous PET and ERP studies and supplement them with the circuitry of cortical information transfer. Also, they suggest some differences in information processing during automated reading and performance of more complicated use-generation task.  相似文献   

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