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Ten children from each group of nursing caries, rampant caries, 3-5 dmft/DMFT and caries free children were selected and plaque samples from carious lesion, early carious lesion, sound tooth surface as well as salivary sample were collected. The levels of mutans streptococci and lactobacilli were estimated at all the sample sites. The result further supported the role of mutans streptococci in the initiation and of lactobacilli in the progression of the dental caries.  相似文献   
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The development of next-generation sequencing (NGS) methods for HLA genotyping has already had an impact on the scope and precision of HLA research. In this study, allelic resolution HLA typing was obtained for 402 individuals from Cape Town, South Africa. The data were produced by high-throughput NGS sequencing as part of a study of T-cell responses to Mycobacterium tuberculosis in collaboration with the University of Cape Town and Stanford University. All samples were genotyped for 11 HLA loci, namely HLA-A, -B, -C, -DPA1, -DPB1, -DQA1, -DQB1, -DRB1, -DRB3, -DRB4, and -DRB5. NGS HLA typing of samples from Cape Town inhabitants revealed a unique cohort, including unusual haplotypes, and 22 novel alleles not previously reported in the IPD-IMGT/HLA Database. Eight novel alleles were in Class I loci and 14 were in Class II. There were 62 different alleles of HLA-A, 72 of HLA-B, and 47 of HLA-C. Alleles A123:17, A143:01, A129:11, A168:27:01, A101:23, B114:01:01, B115:10:01, B139:10:01, B145:07, B182:02:01 and C108:04:01 were notably more frequent in Cape Town compared to other populations reported in the literature. Class II loci had 21 different alleles of DPA1, 46 of DPB1, 27 of DQA1, 26 of DQB1, 41 of DRB1, 5 of DRB3, 4 of DRB4 and 6 of DRB5. The Cape Town cohort exhibited high degrees of HLA diversity and relatively high heterozygosity at most loci. Genetic distances between Cape Town and five other sub-Saharan African populations were also calculated and compared to European Americans.  相似文献   
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Knee replacement surgery is the most common joint replacement surgery in England and Wales. Postoperative radiographs are associated with long-term outcome at both early and late stages, and their correct interpretation is therefore vital. These radiographs will commonly be assessed by surgical trainees, emergency doctors, orthopaedic surgeons, nurse practitioners, and radiologists. The aim of this paper is to provide the reader with a systematic approach to assessing these radiographs, whether it be in the immediate postoperative period or during subsequent follow-ups, and to provide sufficient knowledge to critique the procedure. An outline of prostheses and their indications alongside a comprehensive review of the assessment of important angles, alignment, and correct positioning of femoral and tibial components is presented.  相似文献   
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The lobes of the lung slide relative to each other during breathing. Quantifying lobar sliding can aid in better understanding lung function, better modeling of lung dynamics, and for studying phenomenon such as pleural adhesion. We propose a novel measure to characterize lobe sliding in the lung based on the displacement field obtained from image registration of CT scans. When two sliding lobes are modeled as a continuum, the discontinuity in the displacement field at the fissure will manifest as elevated maximum shear—the proposed measure—which is capable of capturing both the level and orientation of sliding. Six human lungs were analyzed using scans spanning functional residual capacity to total lung capacity. The lung lobes were segmented and registered on a lobe-by-lobe basis to obtain the displacement field from which the proposed sliding measure was calculated. The sliding measure was found to be insignificant in the parenchyma, as relatively little tissue shear occurs here. On the other hand, it was elevated along the fissures. Thus, a map of the proposed sliding measure of the entire lung clearly delineates and quantifies sliding between lung lobes. Sliding is a key aspect of lung deformation during breathing. The proposed measure may help resolve artifacts introduced by sliding in deformation analysis techniques used for radiotherapy.  相似文献   
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BackgroundThe use of intravenous (IV) cannulas is an integral part of patient care in hospitals. These intravenous cannulas are a potential route for microorganisms to enter the blood stream resulting in a variety of local or systemic infections. Studies showing the actual prevalence of colonization of peripheral IV cannulas and its role in BSI are lacking. Hence, this study was aimed to estimate the prevalence of colonization of the injection ports of peripheral IV cannulas.MethodsThis cross sectional study was conducted on patients admitted in ICU and wards in an 800 bedded tertiary care hospital. Swabs were taken from lumens of peripheral IV cannulas and cultured. Patient demographic data and practices followed for maintenance of IV line were noted.ResultsA total of 196 injection port samples were taken, out of which 11 tested positive for microbial growth (5.61%). Staphylococcus aureus was the predominant organism contributing 64% of the microbial growth. A significant association was seen between presence of local signs, old age and positive cultures. Flushing IV cannula every 6 h was associated with negative cultures.ConclusionPeripheral IV cannulation has significant potential for microbial contamination and is largely ignored. Most of the risk factors associated with growth of microorganisms in the injection ports of peripheral intravenous cannulas (which has a potential to cause catheter-related blood stream infections) can be prevented by improving protocols for management. To prevent infection from occurring, practitioners should be educated and trained about the care and management of IV.  相似文献   
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