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91.
92.
We briefly review findings from Brazilian settings where the human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) epidemic among injection drug users (IDUs) seems to be decreasing, highlighting recent findings from Rio de Janeiro and discussing methodological alternatives. Former analyses using serologic testing algorithm for recent HIV seroconversion have shown that HIV incidence has been low in IDUs recruited by two different surveys carried out in Rio, where low injection frequencies and infection rates have been found among new injectors. The proportion of AIDS cases among IDUs in Rio has been fairly modest, compared to S?o Paulo and especially to the southernmost states. Notwithstanding, the interpretation of findings from serial surveys constitutes a challenge, magnified in the assessment of HIV spread among IDUs due to the dynamic nature of the drug scenes and limitations of sampling strategies targeting hard-to-reach populations. Assessment of epidemic trends may profit from the triangulation of data, but cannot avert biases associated with sampling errors. Efforts should be made to triangulate data from different sources, besides exploring specific studies from different perspectives. In an attempt to further assess the observed trends, we carried out original analyses using data from Brazilian AIDS databank.  相似文献   
93.
We report tree-based association analysis as applied to the two Framingham cohorts and to the first replication of the simulated data obtained from the Genetic Analysis Workshop 13. For this analysis, familial association is ignored. The two endpoints examined are hypertension status at initial visit and time-to-hypertension, using a censored data approach. Although linkage association has previously been reported with hypertension, we found no association using the tree-based methodology.  相似文献   
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95.
Thyroid stimulating hormone (TSH) hormone levels are normally tightly regulated within an individual; thus, relatively small variations may indicate thyroid disease. Genome-wide association studies (GWAS) have identified variants in PDE8B and FOXE1 that are associated with TSH levels. However, prior studies lacked racial/ethnic diversity, limiting the generalization of these findings to individuals of non-European ethnicities. The Electronic Medical Records and Genomics (eMERGE) Network is a collaboration across institutions with biobanks linked to electronic medical records (EMRs). The eMERGE Network uses EMR-derived phenotypes to perform GWAS in diverse populations for a variety of phenotypes. In this report, we identified serum TSH levels from 4,501 European American and 351 African American euthyroid individuals in the eMERGE Network with existing GWAS data. Tests of association were performed using linear regression and adjusted for age, sex, body mass index (BMI), and principal components, assuming an additive genetic model. Our results replicate the known association of PDE8B with serum TSH levels in European Americans (rs2046045 p = 1.85×10−17, β = 0.09). FOXE1 variants, associated with hypothyroidism, were not genome-wide significant (rs10759944: p = 1.08×10−6, β = −0.05). No SNPs reached genome-wide significance in African Americans. However, multiple known associations with TSH levels in European ancestry were nominally significant in African Americans, including PDE8B (rs2046045 p = 0.03, β = −0.09), VEGFA (rs11755845 p = 0.01, β = −0.13), and NFIA (rs334699 p = 1.50×10−3, β = −0.17). We found little evidence that SNPs previously associated with other thyroid-related disorders were associated with serum TSH levels in this study. These results support the previously reported association between PDE8B and serum TSH levels in European Americans and emphasize the need for additional genetic studies in more diverse populations.  相似文献   
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The presence of Vibrio parahaemolyticus in 123 oyster samples collected from an estuary on the southern coast of Sao Paulo state, Brazil, was investigated. Of the 123 samples, 99.2% were positive with densities ranging from <3 to 105 most probable number (MPN)/g. Densities correlated significantly with water temperature (r = 0.48; P < 0.001) but not with salinity (r = −0.09; P = 0.34). The effect of harvest site on counts was not significant (P > 0.05). These data provide information for the assessment of exposure of V. parahaemolyticus in oysters at harvest.Infections caused by Vibrio parahaemolyticus have been reported in several countries (1, 3-5, 14, 15, 16, 17, 18, 19, 20, 22, 24, 26). Among other pathogenic features, V. parahaemolyticus strains produce a thermostable hemolysin, known as thermostable direct hemolysin (TDH), as well as TRH (a TDH-related hemolysin) (25, 29). However, not all strains are pathogenic, as less than 1% of food or environmental strains produce TDH or TRH (2, 7, 9, 10, 11).The most important vehicle for this microorganism is raw or partially cooked shellfish (8, 13, 25, 29). In this study, the densities of V. parahaemolyticus in oysters collected in six oyster bed sites in the estuary of Cananeia (25°S; 48°W) in the southern coastal area of Sao Paulo state, Brazil (Fig. (Fig.1)1) between May 2004 and June 2005 were determined using the most probable number (MPN) technique by the method of De Paola and Kaysner (12). Each sample consisted of 15 oysters, pooled in a plastic bag, and transported in a cold box to the laboratory located in the city of Sao Paulo, Brazil. The temperature during transportation did not exceed 13°C, and the travel time was around 5 h. In the laboratory, the oysters were kept under refrigeration (4 to 8°C) and analyzed within 24 h of collection. Oysters were cleaned and shucked by the method of Cook et al. (6). Identification of V. parahaemolyticus was based on traditional and API 20E strip biochemical tests (bioMérieux, France), using V. parahaemolyticus ATCC 17802 as the reference strain. The observed prevalence of this bacterium was high, as the microorganism was detected in 99.2% (122/123) of the samples and the densities varied between 0.78 and 5.04 log MPN/g.Open in a separate windowFIG. 1.Locations of oyster bed sites in the Cananeia estuary on the southern coast of Sao Paulo state, Brazil. (Courtesy of E. E. de Miranda and A. C. Coutinho [Embrapa Monitoramento por Satélite] [http://www.cdbrasil.cnpm.embrapa.br].)Strategies for the control of V. parahaemolyticus in oysters depend on understanding the seasonal and geographical distribution and the effects of environmental parameters on the growth of this pathogen. To verify the influence of salinity and temperature of seawater on the density of V. parahaemolyticus, samples of water (n = 123) were collected from the same depth of oyster beds using 250-ml plastic flasks. Salinity was determined using a salinometer (model RS10; Rosemount Analytical, Cedar Grove, NJ), and the temperature was determined at the time of collection using a digital thermometer (Hanna Instruments). The results are shown in Fig. Fig.22.Open in a separate windowFIG. 2.Total densities of Vibrio parahaemolyticus in oysters from the southern coast of Sao Paulo state, Brazil. Each bar or point represents the arithmetic mean of six sites, and each error bar represents the standard deviation.Total V. parahaemolyticus densities did not correlate significantly with water salinity, as determined by Pearson coefficient (r = −0.09; P = 0.34). However, the mean salinity varied significantly according to the sampling site and season (P < 0.05) (Table (Table1).1). The highest mean salinity (24.2 ppt) was detected at site 5 and was 1.4 times higher than at site 2 (17.3 ppt), the lowest mean salinity detected in this study.

TABLE 1.

Seasonal distribution of the total density of Vibrio parahaemolyticus in oysters, water temperature, and salinity in the southern coastal area of Sao Paulo state, Brazil
VariableSeasonNo. of samplesMeanaSDRange
Vibrio parahaemolyticusWinter352.44 A1.06<0.48-4.38
    density (log10Spring293.26 B1.171.04-5.04
    MPN/g)Summer243.47 B0.751.54-5.04
Fall353.48 B1.011.04-5.04
Temp (°C)Winter3520.1 A1.914.4-24.0
Spring2923.6 B1.820.0-26.0
Summer2426.7 C1.424.1-29.2
Fall3523.9 B2.220.6-28.3
Salinity (ppt)Winter3522.3 A4.512.2-29.8
Spring2920.2 AB4.411.2-29.4
Summer2418.2 B4.35.3-25.2
Fall3521.8 A3.98.7-28.2
Open in a separate windowaValues with different letters are significantly different (P < 0.05).The weak correlation between water salinity and V. parahaemolyticus densities in oysters suggests that salinity per se is a secondary factor for growth of this bacterium, as are turbidity and chlorophyll content in water (27, 30). These results agree with those obtained by Deepanjali et al. (9) and Martinez-Urtiga et al. (21), who did not find correlation between these two parameters. However, they are in contrast with the results reported by DePaola et al. (11), who observed correlation (P < 0.05) between salinity and total density of V. parahaemolyticus.The results of this study corroborate existing evidence (10, 11, 27, 30) indicating that the temperature of seawater has a significant correlation (r = 0.48; P < 0.001) on the densities of V. parahaemolyticus in oysters, but they are at odds with results reported by Deepanjali et al. (9), who observed no statistically significant correlation with seawater temperature. The temperature variations observed in the present study (15°C) were lower than those observed by DePaola et al. (22°C) (11) but higher than those reported by Deepanjali et al. (10°C) (9).The relationship between V. parahaemolyticus density and water temperature and salinity were analyzed by multiple linear regression. Results showed that salinity was not significant either for linear effects or for squared effects (P > 0.05). For temperature, while the parameter of linear effect was significant (P < 0.05), the squared effect was not (P > 0.05). Considering the goodness of fit of the model, the following linear regression described the density in oysters the best (Fig. (Fig.3):3): log10 MPN V. parahaemolyticus/g = −0.944 + (0.175 × temperature). The lack of model fitness test was not significant and was considered adequate to express the relationship between V. parahaemolyticus density and seawater temperature, in spite of the low R2 (0.23).Open in a separate windowFIG. 3.Goodness of fit regression model of V. parahaemolyticus density in oysters and water temperature.The effect of temperature was further summarized by rank correlation and the use of a smoothing technique (moving average) in which densities corresponding to temperatures within a range of 1°C were pooled to estimate an arithmetic mean of densities in successive intervals. The moving average was calculated using a length of three values. Although seawater temperature and V. parahaemolyticus densities were correlated in the present study, the mean densities reached a plateau at temperatures above 24°C and below 20°C (Fig. (Fig.4)4) where the density was not significantly influenced by temperature, consistent with observations reported also by DePaola et al. (11). Our findings could explain the lack of correlation among those parameters detected in tropical oysters by Deepanjali et al. (9) when the temperature varied from 25 to 35°C.Open in a separate windowFIG. 4.Relationship between the mean density of V. parahaemolyticus in oysters and seawater temperature in Cananeia estuary, Sao Paulo state, Brazil.The influence of the season of the year and site of collection on the mean densities was assessed by analysis of variance and Tukey''s test, when necessary. As shown in Table Table1,1, the V. parahaemolyticus densities were similar in the samples collected during spring, summer, and autumn but differed significantly (P < 0.05) in those collected during winter. Densities among samples collected during summer varied less compared to other seasons. Densities above 105 MPN/g were detected in six (4.9%) oyster samples (three samples during spring, two samples during summer, and one sample during autumn) collected when the temperature was higher than 24°C and the salinity was higher than 15 ppt. The effect of harvest site on densities was not significant (P > 0.05).Previous studies performed with oysters collected in the same region in Brazil have shown a low incidence of pathogenic V. parahaemolyticus (23, 28). Similar results were observed in the present study, as only one oyster sample (0.8%) and only one isolate among 2,243 isolates tested (0.044%) were Kanagawa and tdh positive. Besides the Kanagawa reaction (24), all strains have been tested for tlh, tdh, and trh genes using PCR (12). The pathogen-positive sample presented with a low density of V. parahaemolyticus (3 MPN/g) and was collected during winter, when the temperature was 21°C. Due to the low incidence of pathogenic strains in the samples, correlation between pathogenicity and water temperature or salinity could not be determined.This study indicates that the presence of V. parahaemolyticus in oysters cultivated in the southern coast of Sao Paulo state, Brazil, is high, but pathogenic strains are seldom detected. These results on the ecology and characteristics of V. parahaemolyticus are valuable for future risk assessments related to this pathogen in oysters at harvest.  相似文献   
98.
The high proportion of cases of cutaneous leishmaniasis reported amongst residents in the city of Bandeirantes, in the state of Paraná, Brazil, led the authors to investigate the phlebotomine fauna in both urban and rural environments. The sandflies were captured with automatic light traps from 07:00 pm-07:00 am fortnightly in 11 urban peridomiciles from April 2008-March 2009 and monthly in three ecotopes within four rural localities from April 2009-March 2010. In one of these latter localities, sandfly capture was conducted with white/black Shannon traps during each of three seasons: spring, summer and fall. A total of 5,729 sandflies of 17 species were captured. Nyssomyia neivai (46.7%) and Nyssomyia whitmani (35.3%) were the predominant species. In this study, 3,865 specimens were captured with automatic light traps: 22 (0.083 sandflies/trap) in the urban areas and 3,843 (26.69 sandflies/trap) in the rural areas. Ny. neivai was predominant in urban (68.2%) and rural (42.8%) areas. A total of 1,864 specimens were captured with the white/black Shannon traps and Ny. neivai (54.5%) and Ny. whitmani (31.4%) were the predominant species captured. The small numbers of sandflies captured in the urban areas suggest that the transmission of Leishmania has occurred in the rural area due to Ny. neivai and Ny. whitmani as the probable vectors.  相似文献   
99.
Success of alveolar reconstructions using onlay autogenous block bone grafts depends on their adequate integration to the recipient bed influenced by a number of local molecules. Considering the fundamental role of cyclooxygenase (COX-2) in bone repair, the aim of this study was to analyze the effect of its inhibition in the integration of endochondral (EC) iliac crest, and intramembranous (IM) calvaria bone grafts. Thirty-two rabbits were divided into 4 groups: Calvaria Control (CC) and Iliac Control—treated with oral 0.9 % saline solution, and Calvarial-NSAID (C-NSAID) and Iliac-NSAID (I-NSAID) groups—treated with oral 6 mg/Kg non-steroidal anti-inflammatory drug etoricoxib. After 7, 14, 30 and 60 days the animals were euthanized and the specimens removed for histological, histomorphometric and immunohistochemistry analysis. At day 60, a tight integration of IM blocks could be seen with the presence of remodeling bone, whereas integration of EC grafts was mainly observed at the edges of the grafts. A significant higher percentage of bone matrix in the interface region of the CC grafts in comparison to C-NSAID only at day 14, whereas no differences were detected comparing the EC grafts. No differences were observed in Runx-2 and vascular endothelial growth factor (VEGF) immunolabeling when comparing CC and C-NSAID groups, while a significant weaker Runx-2 and VEGF labeling was detected in I-NSAID group at day 60. Although some influence was detected in osteogenesis, it is concluded that drug induced inhibition of COX-2 does not impair onlay bone grafts’ healing of both embryologic origins in rabbits.  相似文献   
100.
Molecular Biology Reports - Lawsone is a natural naphthoquinone present in the henna leaf extract with several cytotoxic activities and used as precursor for synthesis of various pharmaceutical...  相似文献   
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