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1.
《Chronobiology international》2013,30(8):1647-1659
The aim of the study was to examine seasonal variability in monthly admissions for community-acquired pneumonia (CAP) in Taiwan. Our study sample comprised 477,541 pneumonia patients in Taiwan between 1998 and 2005, inclusive. Results showed a fairly consistent seasonal pattern of pneumonia admissions, regardless of sex and age, and for the groups combined. Seasonal trends showed a peak in hospitalizations from January through April, followed by a sharp decrease in May and a trough from August through October. The auto-regressive integrated moving average (ARIMA) test found significant seasonality for all age and sex groups and for the whole sample (all p?<?0.001). After adjusting for seasonality, month, and trends, the ARIMA regression models revealed that the monthly pneumonia admissions rate was significantly associated with ambient temperature, for the total sample, for female groups, and for the 65–74 and?≥75 age groups (all p?<?0.01). A 1°C decrease in ambient temperature was associated with roughly a 0.03 increase in monthly pneumonia admissions rate (per 10,000 people) for the entire sample. We conclude the monthly pneumonia admissions rate was significantly associated with seasonality, and was higher in periods with low ambient temperatures. (Author correspondence: henry11111@tmu.edu.tw)  相似文献   

2.
Population dynamics of the Oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), were monitored year‐round using methyl eugenol‐baited traps in 2003, 2004, 2005 and 2006 in Baoshanba, Yunnan Province, China. Environmental factors including air temperature, rainfall and host‐plant species were analyzed with respect to the population dynamics. This species occurred only during April–November, with one yearly peak in August. The population fluctuation patterns with respect to season were identical in all study years. Correlation analysis and stepwise regression analysis indicated that air temperature, rainfall, sunlight hours and relative humidity were the major climatic factors that correlated with changes in the size of the fly population, and that monthly mean temperature, monthly sunlight hours and monthly relative humidity were most important. The seasonal increase in population size coincided with the fruiting period of the fly's host plants, but host fruit availability influenced the population size only when temperatures were sufficiently high. Cold temperatures may explain why there was no trap capture in the winter months. We believe that air temperature is the key factor explaining the seasonal occurrence of the fly population at Baoshanba.  相似文献   

3.
The purposes of this study were to evaluate the incidence of high-risk human papillomavirus (HPV) infection by polymerase chain reaction (PCR) and to assess its diagnostic usefulness in primary cervical screening. PCR testing for HPV type 16, 18, 31 and 33 was performed on 1305 specimens obtained during routine cervical cancer screening. We analysed the concurrent cervical smears and biopsy, and correlated them with the HPV infection status. We also evaluated histologically-proven cases with ASCUS smears according to HPV infection. HPV DNA was identified in eight (0.7%) of 1144 cytologically normal patients; nine (10.5%) of 86 ASCUS; seven (25.0%) of 28 LSIL; 26 (78.8%) of 33 HSIL; and in all of three squamous cell carcinomas (SCC). HPV positivity was significantly associated with cytohistological diagnosis for HSIL of more. In addition, HPV-positive ASCUS cases were found to be associated with histological abnormality rather than HPV-negative. The results indicate that high-risk HPV testing by PCR could be a useful adjunct tool for Pap smear in primary cervical screening. The combination of Pap smear and high-risk HPV testing by PCR might reduce unnecessary colposcopy-guided biopsy of women with cytological diagnosis of ASCUS.  相似文献   

4.
OBJECTIVE: Our aim was to assess the validity of non-classical cytological signs in minimally abnormal cervical smears for the prediction of HPV infection. METHODS: 164 ThinPrep monolayers were re-screened for mild nuclear changes, disorders of keratinisation, abortive koilocytes and 'measles cells', as well as degenerative changes. HPV DNA was detected by GP5+/6+ and MY09/MY11 consensus primer PCR assays. RESULTS: Seventy six of 164 cases (46.3%) had HPV positivity by PCR. All cytomorphological features studied were significantly associated with the presence of HPV. Mild nuclear changes had 100% sensitivity and 100% negative predictive value for HPV infection. CONCLUSIONS: Our results indicate that non-classic cytomorphological signs can improve the sensitivity of cytology for detecting HPV. Minimally abnormal Pap smears lacking mild nuclear changes (16%) in the present study--do not require further molecular HPV testing.  相似文献   

5.
Objective: To determine the prevalence of high‐risk human papillomavirus (HR‐HPV) 16/18 infection of uterine cervix among women in the reproductive age group, with cytologically normal cervical (Pap) smears; to analyse the risk factors for HR‐HPV acquisition and to address their implications for cervical cancer screening and prophylaxis in a low resource setting. Methods: Cervical samples from 769 cytologically negative women (age 18–45 years) attending a tertiary care centre in Delhi were subjected to HPV DNA testing and HR‐HPV 16/18 and low‐risk (LR)‐HPV 6/11 sub‐typing by polymerase chain reaction. Univariate risk factor analysis was carried out in HR‐HPV positive (n = 86) versus HR‐HPV negative women (n = 683) by chi‐square test. Results: The overall HPV prevalence among cytologically normal women was 16.6%. HR‐HPV16 was detected in 10.1%, whereas HPV18 was detected in 1% of women. HR‐HPV 16/18 comprised 67% of the total HPV positives. There was no decline in HR‐HPV positivity with age, and women aged 40–44 years were at significantly increased risk for HR‐HPV prevalence (P = 0.03). Statistically significant associations of HR‐HPV infection were found with risk factors such as high parity (P = 0.04), cervicitis/hypertrophic cervix (P = 0.01), unhealthy cervix (P = 0.04), rural residence (P = 0.03), low socioeconomic status (P = 0.01) and illiteracy (P = 0.07). Conclusions: Although the sample size was small, based on the observation that HR‐HPV 16 and 18 contributed significantly to the overall HPV prevalence in our setting, we speculate that testing/prophylaxis for these prevalent high‐risk types could perhaps make cervical cancer screening and preventive programmes cost‐effective. Larger community‐based studies on HPV prevalence and persistence are required to validate these findings before definitive recommendations can be made to the policy makers.  相似文献   

6.
In 110 white West Midlands children serum 25-hydroxy vitamin D (25-OHD) concentrations showed a pronounced seasonal variation, the values being highest in August and lowest in February. The concentrations correlated significantly both with recorded sunlight and with seasonal ultraviolet energy of the sunlight. Children who had had a seaside holiday the previous summer had a higher mean 25-OHD concentration than those who had not had a summer holiday away from home. Correlation between vitamin D intake and serum 25-OHD concentration was not significant.  相似文献   

7.
 Based on records from the Federal Bureau for Statistics of Germany, the seasonality of mortality was investigated for the period 1946–1995. Lowest mortality rates were found during summer (August or September) while highest values were found in winter (January through March). Non-linear regression of all monthly mortality data with the average monthly temperatures in Germany revealed a significant negative relationship (r=–0.739; n=600; P<0.0001). The fact that the differences between the long-range monthly temperatures and the individual monthly temperatures also showed a distinct relationship to the mortality rates speaks against a mere coincidence of both parameters. The amplitude of this seasonal rhythm declined steadily within the observation period. It is concluded that low temperatures cause an increase in mortality rates and that this effect has become less important during recent decades due to the increased use of central heating and because of improvements in the public health system. Received: 27 April 1998 / Revised: 10 July 1998 / Accepted: 9 September 1998  相似文献   

8.
The aim of this study was to investigate the role of methylenetetrahydrofolate reductase (MTHFR) polymorphisms and MTHFR methylation pattern in cervical lesions development among women from Romania, a country with high prevalence of human papillomavirus (HPV) cervical infections. To achieve this goal, blood samples and cervical cytology specimens (n = 77)/tumour tissue specimens (n = 23) were investigated. As control, blood and negative cytological smears (n = 50) were used. A statistically significant association was found between T allele of C677T polymorphism and cervical lesions, heterozygote women presenting a threefold increased risk (normal/cervical lesions and tumours: wild homozygote 34/41 (0.68/0.41), heterozygote 14/51 (0.28/0.51), mutant homozygote 2/8 (0.04/0.08); OR = 3.081, P = 0.0035). Using χ square test for the control group, the HPV‐negative and HPV‐positive patients with cervix lesions, a significant correlation between viral infection and T allele of C677T polymorphism (P = 0.0287) was found. The MTHFR promoter was methylated in all HGSIL and tumour samples, significant differences being noted between HPV‐positive samples, control group and cases of cervical dysplastic lesions without HPV DNA (P < 0. 0001) and between samples from patients with high‐risk (hr)HPV versus low‐risk (lr)HPV (P = 0.0026). No correlations between polymorphisms and methylation were observed. In Romania, individuals carrying T allele are susceptible for cervical lesions. MTHFR promoter methylation is associated with cervical severity lesions and with hrHPV.  相似文献   

9.
The reproductive period of the Glandulocaudine Pseudocorynopoma doriai was determined by the analysis of 240 females, 90 males and 138 immature individuals collected monthly in the Manantiales and the El Portugués rivers. The reproductive period is seasonal, occurring from late winter to mid‐summer, with another reproductive peak of smaller magnitude in early autumn. The mean monthly GSI in males has a significant correlation with rainfall. Other analyzed environmental variables, including temperature, photoperiod, pH and conductivity, did not show a correlation with the mean monthly GSI in females and males. First maturity in females was reached within the 42–43 mm standard length class. Like other Glandulocaudines from southern Brazil, males initiate sexual maturation before females, which implies an adaptive advantage in that this would enable females to spawn under optimal environmental conditions. The mean absolute fecundity was 1286.42 oocytes (SD = 496.9083); the mean relative fecundity was 0.5070 (SD = 0.1333) oocytes by milligram body weight.  相似文献   

10.
Consistent evidence underlines the utility of human papillomavirus (HPV) DNA testing in the management of women with equivocal cervical cytological abnormalities, but not in case of low-grade lesions. We performed a meta-analysis including studies where the high-risk probe of the Hybrid Capture-II is used to triage these two cytological categories. The triage test-positivity rate reflects the colposcopy referral workload.Data were pooled on the HPV test positivity rate in women with atypical squamous cells of undetermined significance (ASCUS/ASC-US) or low-grade squamous intraepithelial lesions (LSIL), derived from different cytological classification systems. The meta-analysis was restricted to studies, published between 1991 and 2007. A random-effect model was applied for meta-analytical pooling and the influence of covariates on the HPV positivity rate was analyzed by meta-regression. The variation by age was assessed within individual studies since age strata were not defined uniformly. On an average, 43% (95% CI: 40–46%) of women with ASCUS/ASC-US were high-risk HPV positive (range 23–74%). In women with LSIL, the pooled positivity rate was 76% (95% CI: 71–81%; range 55–89%). In spite of considerable inter-study heterogeneity, the difference in HPV positivity between the two triage groups was large and highly significant: 32% (95% CI: 27–38%). HPV rates dropped tremendously as age and cutoffs of test positivity increased. Other factors (cytological classification system, country, continent, collection method and year of publication) had no statistically significant impact, except in LSIL triage where HPV positivity was significantly lower in European compared to American studies. Women with LSIL, especially younger women, have high HPV positivity rates suggesting limited utility of reflex HPV triaging these cases. Research is needed to identify more specific methods to triage women with low-grade squamous cervical lesions.  相似文献   

11.
In 6 isolated adult male lesser mouse lemurs, concentrations of testosterone in plasma were determinated at 6-h intervals over a 24-h period. Blood samples were collected at monthly intervals and for a period of 12 months under natural photoperiod. In this nocturnal prosimian, there were no apparent diurnal changes in testosterone concentrations during the non-breeding season (autumn). During seasonal sexual activity (January-August), diurnal changes in testosterone concentrations were characterized by a significant rise during the light phase. The daily testosterone peak occurred about 8.5 h after sunrise from February to July, but at the beginning (January) or at the end (August) of the breeding season, the daily testosterone peak was displaced to the morning. A circannual testosterone rhythm occurred with the highest testosterone values in May/June and the lowest values 6 months later. The dramatic fall in testosterone concentrations after the summer solstice may be associated with a change in the peripheral metabolism of testosterone.  相似文献   

12.
目的:调查安康地区女性人乳头瘤病毒(HPV)感染的基因型别及年龄分布特征,分析其与宫颈癌的关系,为宫颈癌防治及HPV疫苗研发提供可靠的依据。方法:收集2010年6月-2012年8月间在本院及安康市部分县级医院妇产科就诊的2736名女性的液基细胞学和组织学标本,分为8个年龄组:16-24岁119例、25-29岁230例、30-34岁343例、35-39岁472例、40-44岁574例、45-49岁512例、50-54岁206例、55-86岁280例,进行病理学分类及HPV分型检测,分析不同年龄组及不同类型宫颈组织中的HPV感染率。结果:2736例女性中发生HPV感染720例(26.32%),共检出21种型别,感染率最高的基因型别是HPV16(25.05%),其他常见型别依次为HPV58、HPV52、HPV6、HPV11。单一感染占76.25%,多重感染占23.75%。HPV感染率在16-24岁、35-39岁和55-86岁三个年龄段出现高峰;而高危型HPV的感染率在35-39岁和55-86岁两个年龄段分别出现高峰。HPV的检出率随着宫颈病变的严重程度而增加,其中正常或炎症人群的HPV感染率显著低于宫颈病变及宫颈鳞状细胞癌患者(均P0.05),且意义未明的不典型鳞状细胞(ASCUS)、CIN1-3及宫颈鳞状细胞癌患者的HPV感染率对比结果存在显著差异(P0.05)。CIN1组、CIN2-CIN3组及宫颈鳞状细胞癌组单一感染率逐渐增加(P0.05),且其二重、三重感染率比较差异均有统计学意义(P0.05)。结论:安康地区HPV16型别感染较广,临床需加强对HPV16型单一感染宫颈病变患者的癌症预防工作。  相似文献   

13.
The value of cervical (Papanicolaou) smears in monitoring the natural history of cervical human papillomavirus (HPV) infections was assessed in a series of 513 women prospectively followed since 1981. On each clinic visit, the patients were subjected to colposcopy accompanied by cervical smears and/or punch biopsies. The latter were analyzed by light microscopy for concomitant cervical intraepithelial neoplasia (CIN) and by transmission electron microscopy (TEM) for HPV particles as well as for HPV structural proteins. The stromal immunocompetent cell (ICC) infiltrates were phenotypically characterized using monoclonal antibodies for T-cell subsets, NK and K cells and Langerhans cells. HPV DNA typing was accomplished by Southern blot, spot and in situ hybridization using probes for HPV 6, 11, 16, 18 and 31. Lesions showing only changes consistent with HPV infection (HPV-NCIN) were associated with less severe atypia in cervical smears than were lesions with coexistent CIN (HPV-CIN). Normal smears were observed, however, in 24.7% of the cases with HPV-NCIN lesions, in 11.5% of cases with HPV-CIN I lesions but only exceptionally in cases with HPV-CIN II and III lesions (2.2% and 3.3%). The percentages of the different ICC phenotypes did not correlate with the atypia in cervical smears, but there was a shift towards the lower values of the T-helper/T-suppressor (OKT4+/OKT8+) cell ratio in parallel with increasing atypia. The possibility of latent HPV infection was suggested by the detection of viral particles, HPV antigens and HPV DNA in lesions shedding normal cells in the smears. The high-risk HPV types 16 and 18 were associated with the highest frequency of severely atypical cells; in the majority of cases, the low-risk types HPV 6 and 11 presented with less severe atypia. The first cervical smear seems to be of value as a predictor of the natural history of HPV lesions, as indicated by the fact that regression was inversely and progression directly related to initial cellular atypia. The present results confirm the intimate association between HPV infections and CIN. Although the biologic potential of the HPV infections seems to be dependent on multiple factors, routine cervical smears, because of their potential value in monitoring the natural history of this infection, should constitute an important means in the prospective follow-up of these patients.  相似文献   

14.
As current evidence suggests the involvement of epigenetic modification of tumour suppressor genes in human cancer, we investigated the aberrant promoter methylation of FHIT and RASSF1A genes in human papillomavirus (HPV)-mediated cervical cancer in Indian women. We analysed 60 cervical cancer tissue biopsies of different clinical stage and histological grading and 23 healthy control samples with normal cervical cytology. Methylation-specific polymerase chain reaction (MSP) was performed to analyse the methylation status of FHIT and RASSF1A genes and confirmed by sequencing. Both patients and controls were screened for HPV infection and 98% of the HPV-infected cases showed positivity for HPV type 16. Aberrant promoter methylation of the FHIT gene was found in 28.3% (17/60) of cases and of the RASSF1A gene in 35.0% (21/60) of cases; promoter methylation of both the genes was found in 13.3% (8/60) of cervical cancer cases. Methylation was significantly (p<0.01) associated with the cervical cancer cases compared with controls. None of the 23 controls was found to be methylated in either of these genes. This is the first study indicating a correlation between the promoter methylation of FHIT and RASSF1A genes and the clinical stage and histological grading of cervical carcinoma in Indian women. Future studies are underway to examine the practical implications of these findings for use as a biomarker.  相似文献   

15.
Very little is known in the UK about long term trends of theAlternaria spore although it is known to trigger asthma. It hasrecently become apparent that Alternaria spore levels areincreasing in Derby and a detailed study of Alternaria wasundertaken to investigate the increase in numbers, seasonal variationand diurnal periodicity. The seasonal (June—October)Alternaria spore concentrations show a distinct upward trendand there is evidence of an earlier seasonal start and an increase inthe seasonal duration. There has been a dramatic rise in the number ofdays with an Alternaria spore count above 50 spores per cubicmetre, with the peak daily count usually occurring in August butoccasionally in late July or early September. August generally has thehighest monthly total and for 1991–1998 there was a positivecorrelation with monthly rainfall and average temperature. Day to dayspore levels show a positive correlation between Alternariaspore concentrations and maximum temperature but a slight negativecorrelation with daily rainfall. The peak time for spore capture is14.00–22.00, and more than half the daily Alternariacatch is caught between 18.00 and 24.00 hours. The upward trend inAlternaria spore concentrations may be responsible forincreasing levels of respiratory disease, especially during harvesttime.  相似文献   

16.

Objective

HPV infection is a common finding, especially in young women while the majority of infections are cleared within a short time interval. The aim of this study was to examine the efficacy of HPV DNA and mRNA testing in a population attending colposcopy units of two University hospitals.

Methods

1173 liquid based cervical samples from two colposcopy clinics were tested for HPV DNA positivity using a commercial typing kit and HPV E6/E7 mRNA positivity with a flow cytometry based commercial kit. Statistic measures were calculated for both molecular tests and morphological cytology and colposcopy diagnosis according to histology results.

Results

HPV DNA, high-risk HPV DNA, HPV16 or 18 DNA and HPV mRNA was detected in 55.5%, 50.6%, 20.1% and 29.7% of the cervical smears respectively. Concordance between the DNA and the mRNA test was 71.6% with their differences being statistically significant. Both tests’ positivity increased significantly as lesion grade progressed and both displayed higher positivity rates in samples from women under 30 years old. mRNA testing displayed similar NPV, slightly lower sensitivity but significantly higher specificity and PPV than DNA testing, except only when DNA positivity for either HPV16 or 18 was used.

Conclusions

Overall mRNA testing displayed higher clinical efficacy than DNA testing, either when used as a reflex test or as an ancillary test combined with morphology. Due to enhanced specificity of mRNA testing and its comparable sensitivity in ages under 25 or 30 years old, induction of mRNA testing in young women could be feasible if a randomized trial verifies these results.  相似文献   

17.
分别研究了实验室条件卜紫外灯照射及不同季节中目光照射对噬藻体PP活性的影响。结果表明紫外光(UV-A和UV-B)对噬藻体PP有较强的致失活作用,并且其致失活作用强弱与波长有关。日光的作用下,夏季时噬藻体PP的日失活率为88.60%,冬季时为58.86%。同时发现不同季节中,尽管在某些时段的目光强度相似,但噬藻体PP失活率的差别却较大,这一现象可能是由于光质不同引起的。上述结果有助于解释淡水环境中噬藻体种群大小的季节性波动。  相似文献   

18.
G. Pizelle 《Plant and Soil》1984,78(1-2):181-188
Summary The seasonal variations of the growth of sexual reproductive organs and of the nitrogenase activity (acetylene reduction) of root nodules are surveyed in mature field alders (Alnus glutinosa). The growth of female catkins—pollinated in February-early March—takes place chiefly from June to August and the growth of immature male catkins from July to September. The nitrogenase activity steadily shows two periods of high rate—the first from late April to early June, the second in September–October-and a summer period of low rate when the female catkins and the seeds achieve the most part of their growth.The seasonal fluctuations of thein vitro/in vivo nitrogenase activity ratio showing the supply of metabolic factors in the root nodules as a likely cause of the variations of thein vivo nitrogenase activity, the possible competition for photosynthate allocation between the production of sexual organs and the nitrogen-fixing capacity in mature field alders is discussed.  相似文献   

19.
A comparison of different methods for the detection of cervical human papillomavirus (HPV) infection was made on patients attending the cervical dysplasia clinic. Cytomorphology, immunocytochemistry and in situ hybridization were compared for their ability to detect HPV. Separate cervicovaginal smears from 50 patients were tested for HPV types 6/11, 16 and 18 by in situ hybridization using 35S-labeled DNA probes. Duplicate smears from the same patients were Papanicolaou stained and evaluated for evidence of condylomatous and dysplastic changes. Twenty-five matching cervical biopsies were immunostained for HPV capsid antigen and tested by in situ hybridization for HPV DNA. The cytologic smears of 20 patients (40%) were positive for HPV DNA. Six patients had HPV 6/11, ten had HPV 16, three had HPV 18, and one had both HPV 6/11 and HPV 16. There was a high correlation between condylomatous cytopathology and antigen and DNA detection. One-third of the specimens with condylomatous changes were DNA negative by the tested probes, suggesting the presence of other HPV types in the genital tract.  相似文献   

20.
The p16/INK4A protein is a cellular regulatory polypeptide over-expressed in the presence of high levels of the Human Papillomavirus (HPV) coded E7 protein. This review outlines the use of p16 antigen staining in cervical biopsies as well as in PAP smears summarizing the corresponding literature and commenting the authors’ own experience. The p16 antigen is a reliable marker for dysplastic cells in CINII/CINIII (HSIL) lesions as viewed in cervical biopsies. When PAP smears were examined at large scale screening for p16 antigenreactive and atypical cells, considerable variations could be found especially in ASCUS graded lesions. Therefore, the presence of p16-reactive atypical cells in PAP smears should be interpreted together with the cytological signs of dysplasia, such as the altered N/C ratio. In addition, women revealing p16-positive ASCUS/LSIL specimens should be examined for the presence of HPV DNA. Detection of HPV DNA alone, i.e. in the absence of cytological screening has a low predictive value, since the clearance of HPV may occur even in the absence of morphological alterations. Combined cytological as well as molecular follow up contributes to the efficiency of diagnostic and increases the probability of correct interpretation of the pre-cancerous lesions by non-invasive techniques.  相似文献   

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