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91.
92.
The sperm ultrastructure of Bufo schineideri and B. granulosus consists of entwined seminiferous tubules formed by groups of germ cells and Sertoli cells. The spermatozoa of B. schineideri and B. granulosus measure about 66.7 microm and 85.4 microm in length, respectively. The head measures approximately 24.8 microm in B. schineideri and 17.7 microm in B. granulosus and consists of a single vesicle acrosomal, subacrosomal cone and nucleus. The midpiece measures approximately 3.8 microm in B. schineideri and 2.5 microm in B. granulosus and presents a mitochondrial collar around the tail. The tail consists of a typical axoneme, 9 + 2 microtubules, paraxonemal rod, axial sheath and axial fiber. The axial fiber extends through an electrondense structure that supports the undulating membrane. The structure and ultrastructure of the spermatozoa of the species here described are similar to the majority of sperm found in the other bufonids and may be a contribution for future phylogenetic analysis. 相似文献
93.
KM Kanal NJ Hangiandreou AM Sykes HE Eklund PA Araoz JA Leon BJ Erickson 《Journal of digital imaging》2002,14(1):30-37
The aims of this work were to measure the accuracy of one continuous speech recognition product and dependence on the speaker's
gender and status as a native or nonnative English speaker, and evaluate the product's potential for routine use in transcribing
radiology reports. IBM MedSpeak/Radiology software, version 1.1 was evaluated by 6 speakers. Two were nonnative English speakers,
and 3 were men. Each speaker dictated a set of 12 reports. The reports included neurologic and body imaging examinations performed
with 6 different modalities. The dictated and original report texts were compared, and error rates for overall, significant,
and subtle significant errors were computed. Error rate dependence on modality, native English speaker status, and gender
were evaluated by performing ttests. The overall error rate was 10.3 +/- 3.3%. No difference in accuracy between men and women
was found; however, significant differences were seen for overall and significant errors when comparing native and nonnative
English speakers (P = .009 and P = .008, respectively). The speech recognition software is approximately 90% accurate, and
while practical implementation issues (rather than accuracy) currently limit routine use of this product throughout a radiology
practice, application in niche areas such as the emergency room currently is being pursued. This methodology provides a convenient
way to compare the initial accuracy of different speech recognition products, and changes in accuracy over time, in a detailed
and sensitive manner. 相似文献
94.
Immunological functions in food-restricted rats: enhanced expression of high-affinity interleukin-2 receptors on splenic T cells 总被引:1,自引:0,他引:1
Several immunological functions of B and T cells including IL-2 receptor expression on T cells were measured in 12-month-old Fisher-344 male rats maintained from 6 weeks of age on an ad libitum (AL) or a 40% food-restricted (FR) diet. Direct anti-SRBC plaque-forming cell (PFC) assays revealed a higher response in FR rats than in AL rats when splenocytes were cultured with or without recombinant interleukin-2 (rIL-2). B cell functions were studied by using nylon wool-purified splenic B cells stimulated either with rIL-2, lipopolysaccharide (LPS), or Salmonella typhimurium mitogen (STM) as a thymus-independent antigen. Reserve plaque assay showed no difference between FR and AL rats in the secretion of anti-IgM and anti-IgG antibodies. In addition, no difference was found in proliferation of B cells stimulated by LPS, STM mitogens or rIL-2. Although purified splenic T cells demonstrated an equally proliferative response in FR and AL rats when cultured with concanavalin A (Con A) or phytohemagglutinin (PHA), T cells in FR rats developed higher responses when stimulated with an alloantigen and rIL-2. Time-course studies carried out to measure high-affinity (HA) IL-2 receptor (R) molecules by using purified T cells with rIL-2 and 125I-labeled IL-2 revealed a higher expression of IL-2R molecules on T cells of FR rats than on T cells of AL rats at 72 h after culturing with Con A.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
95.
Lesions of the articular surfaces of the knee have been managed by various techniques over the last 50 years. Surgical management has involved: excising the damaged area, refashioning the underlying bone to produce a fibrous response, and introducing allograft, autograft and synthetic materials to encourage a repair matrix. The techniques and their pitfalls are reviewed and discussed, and suggestions made as to the direction of future studies for the repair of osteochondral lesions in the painful knee. 相似文献
96.
Evaluation of the automated phoenix system for potential routine use in the clinical microbiology laboratory 总被引:5,自引:0,他引:5
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Donay JL Mathieu D Fernandes P Prégermain C Bruel P Wargnier A Casin I Weill FX Lagrange PH Herrmann JL 《Journal of clinical microbiology》2004,42(4):1542-1546
A comparative study was designed to evaluate the identification (ID) and antimicrobial susceptibility testing (AST) performances of the BD Phoenix Automated Microbiology System (Becton Dickinson Diagnostic Systems [BD], Pont de Claix, France). A total of 305 single clinical isolates were collected, and comparisons were made with routine manual methods in use in our microbiology laboratories. The percentages of correct IDs were 93.3, 89.4, 91.8, and 85.7% for enterobacteria, nonfermenting gram-negative bacilli, staphylococci, and streptococci-enterococci, respectively. The median ID time was 3 h, and the median time for AST was 10 h 30 min. AST results showed variable percentages of errors for the different antibiotics. None of the enterobacteria and 0.3% of Pseudomonas aeruginosa isolates showed a very major error (VME). Only one strain of Staphylococcus aureus showed a VME with oxacillin. We demonstrate here the efficiency of the Phoenix system, which can be used for the majority of strains encountered in a university-based laboratory, for ID and AST. 相似文献
97.
Immunological factors in endometriosis-associated reproductive failure: studies in fertile and infertile women with and without endometriosis 总被引:7,自引:4,他引:7
Martinez-Roman S; Balasch J; Creus M; Fabregues F; Carmona F; Vilella R; Vanrell JA 《Human reproduction (Oxford, England)》1997,12(8):1794-1799
Immunopathophysiological mechanisms in endometriosis-associated
reproductive failure were studied in appropriate populations: infertile and
fertile women with and without endometriosis. The incidence of sera
positive for any of the autoantibodies tested among infertile women with
endometriosis (n = 25) was similar to that observed in the three control
groups [unexplained infertility patients (n = 25) and fertile women with (n
= 10) and without (n = 25) endometriosis]. The mean volume of peritoneal
fluid was significantly elevated in women with endometriosis (both fertile
and infertile) as compared with patients without endometriosis (fertile or
infertile). The concentration of peritoneal fluid leukocytes and the
percentage of cells positive for macrophage markers were significantly
increased and the percentage of T lymphocytes significantly decreased in
infertile women with endometriosis but not in patients with unexplained
infertility and fertile women with endometriosis, as compared with fertile
controls without endometriosis. Macrophages from infertile patients with
endometriosis had higher sperm phagocytosis than did those from infertile
women without endometriosis or fertile subjects with or without
endometriosis. Incidences of serum and peritoneal fluid samples embryotoxic
to the in-vitro development of 2-cell mouse embryos were significantly
higher in infertile patients with endometriosis than in unexplained
infertility patients and fertile women with or without endometriosis. It is
concluded that immunological mechanisms of endometriosis-associated
infertility exist but that these peritoneal immunological factors in
infertile women with endometriosis are related to their subfertility rather
than to the presence of ectopic endometrial implants. This is supported by
the lack of immunological abnormalities observed among fertile women with
endometriosis. These immunological abnormalities are lacking in patients
with unexplained infertility.
相似文献
98.
The ileoanal J pouch: radiographic evaluation 总被引:1,自引:0,他引:1
Endorectal ileoanal pull-through offers an attractive alternative to proctocolectomy and ileostomy for patients with ulcerative colitis, Gardner syndrome, and familial polyposis. To our knowledge, a careful radiographic analysis of the ileum, ileal pouch, and ileoanal anastomosis after ileoanal pull-through has not been reported. Thirty-two patients with ulcerative colitis, Gardner syndrome, and familial polyposis underwent colectomy, mucosal proctectomy, and endorectal ileoanal pull-through of a 15-cm ileal "J" pouch and loop ileostomy. Twenty-five (78%) of 32 of all the pouches radiographically demonstrated spiral folds extending from the middle of the pouch to the pectinate line. Other radiographic features included a mesenteric mass effect, pseudopolyps, and a central lucency that indicated intrapouch sutures. Radiographs provide useful information in the postoperative management of the ileal pull-through. 相似文献
99.
Fernandes Priyanka Wang Karina Timmerman Jason Reyes Angela Holmes Faye Olaleye Omonike A. Salihu Hamisu M. Moerchen Victoria A. Belcher Harolyn M. E. Copeland-Linder Nikeea Noble Charlotte A. Vamos Cheryl A. Armstrong Anna Waters Catrina R. Long-White Deneen Brown Claudia Reddy Madhavi M. Kuo Alice 《Maternal and child health journal》2022,26(7):1415-1423
Maternal and Child Health Journal - The Maternal and Child Health (MCH) Pipeline Training Program, promotes development of a diverse health workforce by training undergraduate students from... 相似文献
100.
Osvaldo Santos Miodraga Stefanovska-Petkovska Ana Virgolino Ana Cristina Miranda Joana Costa Elisabete Fernandes Susana Cardoso Antnio Vaz Carneiro 《Nutrients》2021,13(3)
Self-management of health requires skills to obtain, process, understand, and use health-related information. Assessment of adolescents’ functional health literacy requires valid, reliable, and low-burden tools. The main objective of this study was to adapt and study the psychometric properties of the Newest Vital Sign for the Portuguese adolescents’ population (NVS-PTeen). Classic psychometric indicators of reliability and validity were combined with item response theory (IRT) analyses in a cross-sectional survey, complemented with a 3-month test-retest assessment. The NVS-PTeen was self-administered to students enrolled in grades 8 to 12 (12 to 17 years old) in a school setting. Overall, 386 students (191 girls) from 16 classes of the same school participated in the study (mean age = 14.5; SD = 1.5). Internal reliability of the NVS-PTeen was α = 0.60. The NVS-PTeen total score was positively and significantly correlated with Portuguese (r = 0.28) and mathematics scores (r = 0.31), school years (r = 0.31), and age (r = 0.19). Similar to the original scale (for the U.S.), the NVS-PTeen is composed of two dimensions, reading-related literacy and numeracy. Temporal reliability is adequate, though with a learning effect. IRT analyses revealed differences in difficulty and discriminative capacity among items, all with adequate outfit and infit values. Results showed that the NVS-PTeen is valid and reliable, sensible to inter-individual educational differences, and adequate for regular screening of functional health literacy in adolescents. 相似文献