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    Large-needle percutaneous aspiration biopsy of the testicle in men with nonobstructive azoospermia

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    Two hundred thirteen testicular specimens of men with nonobstructive azoospermia were obtained by large-needle percutaneous aspiration biopsy. The mean values of the number of seminiferous tubules per histologic section, dimension, weight, and the fraction of biopsies with spermatogenetic cells (53, 0.2 x 0.3 x 0.62 cm, 385 mg, and 63%, respectively) were similar to those obtained by open or other surgical biopsy techniques that were used for assisted fertilization in the same type of patients

    Large needle percutaneous aspiration biopsy of the testicle in men with nonobstructive azoospermia: technical performance

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    The aim of this study was to relate retrospectively in 215 percutaneous large needle aspiration biopsy (LNAB) of the testicles the number of seminiferous tubules (ST) per testicular biopsy, from differently sized testicles, to the size of the needle used in order to obtain information useful for selecting the needle size according to the testicular size. Clinical, ultrasonographic and pathologic data of 134 patients with nonobstructive azoospermia examined with LNAB were retrospectively analyzed. One hundred and sixty-three testicles with volume>or=10 ml, 39or=6 ml, 13/=20) varied from 83% to 50% with a statistically significant difference among the needle groups (P=0.028) and being 83% in the biopsies with the 18 gauge (g.) needle. The mean number of ST obtained with the 18 g. needle was significantly higher than that obtained with the other needles (P=0.000). In the medium volume testicle group the adequate biopsy incidence varied from 20% to 83.3% with statistical significance among the various needle groups (P=0.042) being 83.3% in the biopsies with the 22 g. needle. In the smaller testicle group the mean number of ST obtained with the 22 g. needle was significantly higher than with the 20 g. needle (71 versus 25, P=0.011). In the patients with nonobstructive azoospermia, the 18 g. needle seemed to offer the best performance in the larger testicles, while in the medium and lower sized testicles the smaller 22 g. needle gave results comparable to or slightly better than the other larger needles

    Fine-needle and large-needle percutaneous aspiration biopsy of testicles in men with nonobstructive azoospermia: safety and diagnostic performance

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    OBJECTIVE: To assess by ultrasonography the safety of the association fine-needle aspiration (FNA) plus a new percutaneous large-needle aspiration biopsy technique (LNAB), and to compare the results obtained with the two techniques in the same testicle and with FNA in the two testicles of the same patient. DESIGN: Retrospective analysis of clinical, ultrasonographic, and pathologic data. SETTING: Clinical and academic research environment. PATIENT(S): Three hundred and eighty-seven testicles of 233 patients (ages 19 to 57 years) with nonobstructive azoospermia were consecutively examined with FNA (154) or FNA + LNAB (233); 54 patients (89 testicles) examined with FNA + LNAB underwent a second ultrasonography up to 63 days after. INTERVENTION(S): Ultrasonography, FNA, LNAB. MAIN OUTCOME MEASURE(S): Hypoechoic area at ultrasonography; cytologic picture at FNA or LNAB of only Sertoli cells (category 1), spermatogenetic cells different from elongated spermatids or spermatozoa (category 2), and elongated spermatids and/or spermatozoa (category 3). RESULT(S): Among the 54 patients monitored by ultrasonography 48 (88.9%) showed no difference and 6 (11.1%) showed an hypoechoic area < or =1 cm in the second image. Category 1 occurred at FNA or LNAB in a very similar number of testicles (36% vs. 36.9%). Categories 2 and 3 were more frequent at LNAB (29.9% vs. 9.8%) and at FNA (54.2% vs. 33.2%), respectively. One hundred and sixty-six patients had both testicles examined by FNA; 147 pair of testicles were concordant for the presence or the absence of spermatozoa or elongated spermatids. In the remaining 19 patients (11.4%), these spermatogenetic cells were shown only in the specimen from one of the two testicles. These 19 patients accounted for 20.0% of 93 patients with spermatogenetic cells in at least one of the two testicles. CONCLUSION(S): The combination of FNA and LNAB did not produce clinically or subclinically relevant complications. No important differences in the identification of category 1 with FNA or LNAB were found. Fine-needle aspiration was more adequate in identifying category 3, which was particularly relevant in 20% of the men who had these cells in at least one of the two testicles

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis

    Dispelling the Myths Behind First-author Citation Counts

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    We conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more sophisticated methods

    Author Index

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    koamabayili/VECTRON-author-checklist: VECTRON author checklist

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    We have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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