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61.
Writing for publication is rewarding; it requires specific skills which are identified and explored in this article. Intending authors are encouraged to be systematic in targeting the audience, prepararing the text, and presenting it to a publisher. The differing styles needed for academic articles, book reviews and letters are explored as are the stages in publication.  相似文献   
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The relationship between fecundability and month of birth was investigated in a cohort of 1526 women who married between 1802 and 1929, using only women whose first marriage occurred before the age of 35 years. On the basis of their time to pregnancy (TTP, calculated as time between wedding and first birth minus gestational length), women were categorized into two groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348) and subfecunds (TTP >18 months, n = 118). By use of logistic regression, cosinor functions with a period of 1 year or 6 months and variable shift and amplitude were fitted through the monthly odds of subfecunds versus fecunds. The best fitting curve was unimodal, with a zenith in September (P = 0.13 for H0: no differences). Exclusion of childless women (n = 36, minimum follow-up 5 years) from the subfecunds led to a similar curve (P < 0.01), while childless women, as compared with fecunds, showed a birth distribution that was best represented with a bimodal curve with zeniths in January and July (P = 0.06). This study provides evidence for the existence of differences in fecundability by month of birth. The cause of this relationship is unclear, but may lie in a melatonin-dependent circannual variability of the quality of the oocyte.   相似文献   
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Enteroinvasive Escherichia coli (EIEC), a distinctive pathogenic form of E. coli causing dysentery, is similar in many properties to bacteria placed in the four species of Shigella. Shigella has been separated as a genus but in fact comprises several clones of E. coli. The evolutionary relationships of 32 EIEC strains of 12 serotypes have been determined by sequencing of four housekeeping genes and two plasmid genes which were used previously to determine the relationships of Shigella strains. The EIEC strains were grouped in four clusters with one outlier strain, indicating independent derivation of EIEC several times. Three of the four clusters contain more than one O antigen type. One EIEC strain (an O112ac:H- strain) was found in Shigella cluster 3 but is not identical to the Shigella cluster 3 D2 and B15 strains with the same O antigen. Two forms of the virulence plasmid pINV have been identified in Shigella strains by using the sequences of ipgD and mxiA genes, and all but two of our EIEC strains have pINV A. The EIEC strains were grouped in two subclusters with a very low level of variation, generally not intermingled with Shigella pINV A strains. The EIEC clusters based on housekeeping genes were reflected in the plasmid gene sequences, with some exceptions. Two strains were found in the pINV B form by using the ipgD sequence, with one strain having an mxiA sequence similar to the divergent sequence of D1. Clearly, EIEC and Shigella spp. form a pathovar of E. coli.  相似文献   
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In a large collaborative screening project, 370 men with idiopathic azoospermia or severe oligozoospermia were analysed for deletions of 76 DNA loci in Yq11. In 12 individuals, we observed de novo microdeletions involving several DNA loci, while an additional patient had an inherited deletion. They were mapped to three different subregions in Yq11. One subregion coincides to the AZF region defined recently in distal Yq11. The second and third subregion were mapped proximal to it, in proximal and middle Yq11, respectively. The different deletions observed were not overlapping but the extension of the deleted Y DNA in each subregion was similar in each patient analysed. In testis tissue sections, disruption of spermatogenesis was shown to be at the same phase when the microdeletion occurred in the same Yq11 subregion but at a different phase when the microdeletion occurred in a different Yq11 subregion. Therefore, we propose the presence of not one but three spermatogenesis loci in Yq11 and that each locus is active during a different phase of male germ cell development. As the most severe phenotype after deletion of each locus is azoospermia, we designated them as: AZFa, AZFb and AZFc. Their probable phase of function in human spermatogenesis and candidate genes involved will be discussed.   相似文献   
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Silicosis is a common occupational lung disease, resulting in fibrotic nodular lesions in the upper lobes of the lung parenchyma. Most of the pneumoconioses are diagnosed on the basis of relevant history and clinico‐radiological correlation. Image‐guided aspiration cytology appears to be poorly yielding and is not usually considered as a diagnostic modality. However, silicosis may sometimes offer a diagnostic challenge because of its radiological resemblance and clinical overlap with pulmonary tuberculosis and neoplastic lesions. We present a unique situation where image‐guided fine needle aspiration cytology (FNAC) has been advised on the basis of nodular upper lobe opacities. The cytology smears revealed hypocellular granular material, while phase contrast and polarized light microscopy highlighted crystalline particles. History of silica dust exposure long back was available after the cytological evaluation, suggesting the diagnosis of pulmonary silicosis. X ray diffraction (XRD) crystallography was also possible on cytology smears, confirming zeolite nano particles of size as small as 40 ? 50 nm as the concerned agent for the first time. Cytological evaluation by phase contrast and polarized light microscopy may be useful for the confirmation of silicosis, supplemented by clinical history and radiological evaluation. XRD on smears may help in determination of chemical nature and particle size. Diagn. Cytopathol. 2016;44:246–249. © 2015 Wiley Periodicals, Inc.  相似文献   
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Ultrasound‐guided fine needle aspiration (USG‐FNA) has enabled cytopathologists to accurately diagnose smaller or non‐palpable lymph nodes (LN) on a regular basis. Pre‐FNA clinical and ultrasonographic factors, such as a patient's age, ratio of short to long axis diameter (S/L ratio), internal echogenicity, and the vascular pattern of a LN, are reported to be able to predict the benign or malignant nature of a LN. This study is designed to test the formula “0.06 × (age) + 4.76 × (S/L ratio) + 2.15 × (internal echo) + 1.80 × (vascular pattern)” generated from the study of Liao et al. as a scoring system for predicting LN malignancy in a cytopathologist operated USG‐FNA practice. Eighty‐three reports of USG‐FNA of LNs issued between 7/1/2008 and 4/28/2010 were reviewed. Patient's age, S/L ratio, internal echo, and vascular pattern were used to generate scores based on the aforementioned formula. A score of seven was used as a cutoff for predicting benign (<7) and malignant (>7) LNs. FNA cytology diagnosis, flow cytometric analysis as well as subsequent surgical diagnosis in some cases served as gold standard for statistical analysis. Among 46 USG‐FNA of LNs with scores > 7, 38 were malignant and eight were benign. All 37 USG‐FNA of LNs with scores < 7 were proven to be benign. The scoring system achieved 100% sensitivity, 82% specificity, 83% positive predictive value, 100% negative predictive value, and 90% accuracy. Further study of the eight “false‐positive” cases revealed that three of them (37.5%) were found to be malignant in follow‐up FNA and/or surgical biopsy. This scoring system may serve as a complementary tool in determining how aggressive a FNA procedure should be performed, how a FNA sample of LN should be triaged for ancillary study, and how closely a patient with lymphadenopathy should be followed up. Diagn. Cytopathol. 2013;41:1100–1106. © 2011 Wiley Periodicals, Inc.  相似文献   
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