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91.
目的了解深圳市公共场所从业人员性病、艾滋病相关知识需求。探讨现阶段对公共场所从业人员性病艾滋病干预的有效措施。方法采用整群抽样方法,对公共场所从业人员进行问卷调查。结果一年中,公共场所从业人员有13.3%去过条件差的诊所注射,7.7%会去条件差的诊所拔牙;1101人(93.7%)生殖器官出现症状时会主动去正规医院就医;5.4%的人报告得过性病;34.6%的人愿意接受免费的安全套;31.9%的人想学习安全套使用的技巧;约80%的女性调查对象愿意每年进行一次妇科保健检查。结论健康教育和干预应具体化、生活化,使教育对象在日常生活中采取艾滋病(AIDS)预防措施。分析不能实行相关健康行为的主要原因:(1)受经济条件限制;(2)未掌握实行技巧。提示行为干预应注重技巧的培训,同时考虑目标人群的经济水平,为其创造相应的条件。 相似文献
92.
PC Morris JN Cawson GS Balasubramaniam 《Journal of Medical Imaging and Radiation Oncology》1999,43(1):12-15
Two cases of epidermal cyst of the breast, a rare benign condition, were detected during a 3-year period in a mammographic screening programme, from 57 954 screening examinations. It is not uncommon for epidermal cysts to be initially misdiagnosed. The mammographic, ultrasound and histological features are presented. It is recommended that these lesions be resected because they possibly have malignant potential. 相似文献
93.
The word tracheostomy derived from two greek words meaning ‘I cut the trachea’ has been known for about 3500 yrs. The process has evolved over the years and has undergone revolutionary changes in the methodology, instrumentation and indications. Although tracheostomy is now commonly used the complication rate remains high. In our series it was 48% which is comparable with other series. The purpose of this paper is to discuss the complications of tracheostomy with special attention to their management and prevention.KEY WORDS: Complications, Tracheostomy 相似文献
94.
Purushottam D. Dixit Tin Yau Pang F. William Studier Sergei Maslov 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(29):9070-9075
An approximation to the ∼4-Mbp basic genome shared by 32 strains of Escherichia coli representing six evolutionary groups has been derived and analyzed computationally. A multiple alignment of the 32 complete genome sequences was filtered to remove mobile elements and identify the most reliable ∼90% of the aligned length of each of the resulting 496 basic-genome pairs. Patterns of single base-pair mutations (SNPs) in aligned pairs distinguish clonally inherited regions from regions where either genome has acquired DNA fragments from diverged genomes by homologous recombination since their last common ancestor. Such recombinant transfer is pervasive across the basic genome, mostly between genomes in the same evolutionary group, and generates many unique mosaic patterns. The six least-diverged genome pairs have one or two recombinant transfers of length ∼40–115 kbp (and few if any other transfers), each containing one or more gene clusters known to confer strong selective advantage in some environments. Moderately diverged genome pairs (0.4–1% SNPs) show mosaic patterns of interspersed clonal and recombinant regions of varying lengths throughout the basic genome, whereas more highly diverged pairs within an evolutionary group or pairs between evolutionary groups having >1.3% SNPs have few clonal matches longer than a few kilobase pairs. Many recombinant transfers appear to incorporate fragments of the entering DNA produced by restriction systems of the recipient cell. A simple computational model can closely fit the data. Most recombinant transfers seem likely to be due to generalized transduction by coevolving populations of phages, which could efficiently distribute variability throughout bacterial genomes.The increasing availability of complete genome sequences of many different bacterial and archaeal species, as well as metagenomic sequencing of mixed populations from natural environments, has stimulated theoretical and computational approaches to understand mechanisms of speciation and how prokaryotic species should be defined (1–8). Much genome analysis and comparison has been at the level of gene content, identifying core genomes (the set of genes found in most or all genomes in a group) and the continually expanding pan-genome. Population genomics of Escherichia coli has been particularly well studied because of its long history in laboratory research and because many pathogenic strains have been isolated and completely sequenced (9–14). Proposed models of how related groups or species form and evolve include isolation by ecological niche (7–9, 11, 15), decreased homologous recombination as divergence between isolated populations increases (2–4, 8, 14, 16), and coevolving phage and bacterial populations (6).E. coli genomes are highly variable, containing an array of phage-related mobile elements integrated at many different sites (17), random insertions of multiple transposable elements (18), and idiosyncratic genome rearrangements that include inversions, translocations, duplications, and deletions. Although E. coli grows by binary cell division, genetic exchange by homologous recombination has come to be recognized as a significant factor in adaptation and genome evolution (9, 10, 19). Of particular interest has been the relative contribution to genome variability of random mutations (single base-pair differences referred to as SNPs) and replacement of genome regions by homologous recombination with fragments imported from other genomes (here referred to as recombinant transfers or transferred regions). Estimates of the rate, extent, and average lengths of recombinant transfers in the core genome vary widely, as do methods for detecting transferred regions and assessing their impact on phylogenetic relationships (12–14, 20, 21).In a previous comparison of complete genome sequences of the K-12 reference strain MG1655 and the reconstructed genome of the B strain of Delbrück and Luria referred to here as B-DL, we observed that SNPs are not randomly distributed among 3,620 perfectly matched pairs of coding sequences but rather have two distinct regimes: sharply decreasing numbers of genes having 0, 1, 2, or 3 SNPs, and an abrupt transition to a much broader exponential distribution in which decreasing numbers of genes contain increasing numbers of SNPs from 4 to 102 SNPs per gene (22). Genes in the two regimes of the distribution are interspersed in clusters of variable lengths throughout what we referred to as the basic genome, namely, the ∼4 Mbp shared by the two genomes after eliminating mobile elements. We speculated that genes having 0 to 3 SNPs may primarily have been inherited clonally from the last common ancestor, whereas genes comprising the exponential tail may primarily have been acquired by horizontal transfer from diverged members of the population.The current study was undertaken to extend these observations to a diverse set of 32 completely sequenced E. coli genomes and to analyze how SNP distributions in the basic genome change as a function of evolutionary divergence between the 496 pairs of strains in this set. We have taken a simpler approach than those of Touchon et al. (13), Didelot et al. (14), and McNally et al. (21), who previously analyzed multiple alignments of complete genomes of E. coli strains. The appreciably larger basic genome derived here is not restricted to protein-coding sequences and retains positional information. 相似文献
95.
Se malt cakes containing 300μg selenium were taken up daily to men from high risk area in lung cancer and the influences of Ultraviolet (UV) and Benaopyrene (BαP) induced unscheduled DNA synthesis (UDS) were determined. The Se levels in serum, hair and activity of GSH-px were increased by 89%, 67% and 178%, respectively, after Se-supplementation for half year. In the UV treatment, the ratio of UDS was decreased from the mean values of 2. 47 in the control to 1. 61 (P<0. 05) in the Se-group, In the BaP treatment, furthermore, the elevated Se levels of 78% in serum and 83% in the hair accompanied with 56% high in activity of GSH-px were followed by the Se intake for one year, while the mean value of UDS was reduced from 2. 21 in the control to 1. 47(P< 0. 05) in the group of selenium tested. The blocking effects of UV irradiation and BaP treatment induced UDS of peripheral lymphocytes were showed in the Se-supplementation. 相似文献
96.
To report our clinical experience on the use of oral erythromycin for the treatment of severe gastrointestinal dysmotility in preterm infants.
A case series study of seven preterm infants (six were very low birthweight) with severe intestinal dysmotility in a tertiary neonatal centre.
All responded favourably without adverse effects and tolerated full enteral feeding within 1–2 weeks of the commencement of the drug.
As prolonged total parenteral nutrition carries significant risk of complications, this therapy could be considered in selected preterm infants who fail to establish enteral feeding after an extended period, and in whom an anatomically obstructive lesion of the gastrointestinal tract has been excluded. Meanwhile, we would caution against the widespread implementation of this therapeutic approach until formal evaluation by randomized controlled trials have established the exact role of erythromycin, or its analogues, in the treatment of intestinal dysmotility in preterm infants. 相似文献
Methodology:
A case series study of seven preterm infants (six were very low birthweight) with severe intestinal dysmotility in a tertiary neonatal centre.
Results:
All responded favourably without adverse effects and tolerated full enteral feeding within 1–2 weeks of the commencement of the drug.
Conclusions:
As prolonged total parenteral nutrition carries significant risk of complications, this therapy could be considered in selected preterm infants who fail to establish enteral feeding after an extended period, and in whom an anatomically obstructive lesion of the gastrointestinal tract has been excluded. Meanwhile, we would caution against the widespread implementation of this therapeutic approach until formal evaluation by randomized controlled trials have established the exact role of erythromycin, or its analogues, in the treatment of intestinal dysmotility in preterm infants. 相似文献
97.
Conventional alginate pellets underwent rapid drug dissolution and loss of multiparticulate characteristics such as aggregation in acidic medium, thereby promoting oral dose dumping. This study aimed to design sustained-release dispersible alginate pellets through rapid in situ matrix dispersion and cross-linking by calcium salts during dissolution. Pellets made of alginate and calcium salts were prepared using a solvent-free melt pelletization technique that prevented reaction between processing materials during agglomeration and allowed such a reaction to occur only in dissolution phase. Drug release was remarkably retarded in acidic medium when pellets were formulated with water-soluble calcium acetate instead of acid-soluble calcium carbonate. Different from calcium salt-free and calcium carbonate-loaded matrices that aggregated or underwent gradual erosion, rapid in situ solvation of calcium acetate in pellets during dissolution resulted in burst of gas bubbles, fast pellet breakup, and dispersion. The dispersed fragments, though exhibiting a larger specific surface area for drug dissolution than intact matrix, were rapidly cross-linked by Ca(2+) from calcium acetate and had drug release retarded till a change in medium pH from 1.2 to 6.8. Being dispersible and pH-dependent in drug dissolution, these pellets are useful as multiparticulate intestinal-specific drug carrier without exhibiting dose dumping tendency of a "single-unit-like" system via pellet aggregation. 相似文献
98.
99.
Additive effect of unoprostone and latanoprost in patients with elevated intraocular pressure. 下载免费PDF全文
Tin Aung Paul T K Chew Francis T S Oen Yiong-Huak Chan Lennard H Thean Leonard Yip Boon-Ang Lim Jade Soh Steve K L Seah 《The British journal of ophthalmology》2002,86(1):75-79
AIMS: To assess the additive effect of unoprostone and latanoprost in patients with primary open angle glaucoma (POAG) or ocular hypertension (OHT) METHODS: 32 patients with POAG or OHT were randomised to receive either latanoprost once daily or unoprostone twice daily for 4 weeks. After 4 weeks, all patients received both latanoprost and unoprostone for another 4 weeks. The IOP was measured at 9 am and 5 pm on the baseline, day 28, and day 56 visits, and at 9 am on day 14 and day 42 visits. The medications were given to the patients in an open label fashion. The observer was masked to the treatment given. The mean of the measurements was calculated. Safety parameters were also recorded. The additive effect of the medications was assessed by the reduction in intraocular pressure (IOP) when both medications were used, compared with when one medication was used. RESULTS: 28 patients completed both treatment periods and had IOP data available for evaluation. After 1 month of treatment, latanoprost significantly reduced IOP (mean by 6.1 (SEM 0.8) mm Hg (p<0.001) and unoprostone by 4.9 (1.0) mm Hg (p<0.001) from the baseline of 24.4 (0.6) mm Hg and 24.4 (1.1) mm Hg respectively (p = 0.18). When latanoprost once daily was given to patients treated with unoprostone, there was additional IOP lowering of 1.9 (0.6) mm Hg (p = 0.012). However, adding unoprostone to those being treated with latanoprost produced an IOP change of +0.4 (0.5) mm Hg (p = 0.42). Ocular symptoms and findings were mild and equally distributed between treatment groups, and after combined therapy. Hyperaemia and ocular irritation were the most frequently reported events. Over a third of patients experienced ocular irritation with the combination of medications. CONCLUSIONS: Latanoprost once daily causes additional IOP lowering in eyes which were being treated with unoprostone twice a day. However, there was no additional IOP lowering when unoprostone was added to eyes which were being treated with latanoprost. Both drugs were well tolerated together with few ocular adverse events. 相似文献
100.
Ingo Helbig Marielle E M Swinkels Emmelien Aten Almuth Caliebe Ruben van 't Slot Rainer Boor Sarah von Spiczak Hiltrud Muhle Johanna A J?hn Ellen van Binsbergen Onno van Nieuwenhuizen Floor E Jansen Kees P J Braun Gerrit-Jan de Haan Niels Tommerup Ulrich Stephani Helle Hjalgrim Martin Poot Dick Lindhout Eva H Brilstra Rikke S M?ller Bobby PC Koeleman 《European journal of human genetics : EJHG》2014,22(7):896-901
A genetic contribution to a broad range of epilepsies has been postulated, and particularly copy number variations (CNVs) have emerged as significant genetic risk factors. However, the role of CNVs in patients with epilepsies with complex phenotypes is not known. Therefore, we investigated the role of CNVs in patients with unclassified epilepsies and complex phenotypes. A total of 222 patients from three European countries, including patients with structural lesions on magnetic resonance imaging (MRI), dysmorphic features, and multiple congenital anomalies, were clinically evaluated and screened for CNVs. MRI findings including acquired or developmental lesions and patient characteristics were subdivided and analyzed in subgroups. MRI data were available for 88.3% of patients, of whom 41.6% had abnormal MRI findings. Eighty-eight rare CNVs were discovered in 71 out of 222 patients (31.9%). Segregation of all identified variants could be assessed in 42 patients, 11 of which were de novo. The frequency of all structural variants and de novo variants was not statistically different between patients with or without MRI abnormalities or MRI subcategories. Patients with dysmorphic features were more likely to carry a rare CNV. Genome-wide screening methods for rare CNVs may provide clues for the genetic etiology in patients with a broader range of epilepsies than previously anticipated, including in patients with various brain anomalies detectable by MRI. Performing genome-wide screens for rare CNVs can be a valuable contribution to the routine diagnostic workup in patients with a broad range of childhood epilepsies. 相似文献