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BACKGROUND: Alveolar soft part sarcoma is a rare soft tissue tumor of uncertain origin usually affecting young adults. This neoplasm has early metastatic potential. Its cytologic features, particularly when presenting with metastases, have rarely been described. CASE: A 23-year-old male presented with shortness of breath and scapular pain. Routine chest roentgenograms revealed multiple lung nodules. Malignancy was established by percutaneous fluoroscopically guided fine needle aspiration on a lung nodule. Possible metastatic alveolar soft part sarcoma was suggested by cytology among few considerations in the differential diagnosis. Alveolar soft part sarcoma was confirmed by lung core biopsy and further supported by immunohistochemistry and electron microscopy. Tumor cells expressed muscle-specific actin and myoglobin, and contained diastase-resistant inclusions with periodic acid-Schiff stain. Ultrastructurally, peculiar, elongated intracytoplasmic crystalline bodies typical of this neoplasm were identified. A meticulous clinical search led to finding the primary tumor deeply located in the right posterior thigh. CONCLUSION: Aspiration cytology is a reliable, cost-efficient technique in the diagnostic workup of masses suspicious for malignancy.  相似文献   
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Polymerase chain reaction (PCR) products corresponding to 803 bp of the cytochrome oxidase subunits I and II region of mitochondrial DNA (mtDNA COI-II) were deduced to consist of multiple haplotypes in three Sitobion species. We investigated the molecular basis of these observations. PCR products were cloned, and six clones from one individual per species were sequenced. In each individual, one sequence was found commonly, but also two or three divergent sequences were seen. The divergent sequences were shown to be nonmitochondrial by sequencing from purified mtDNA and Southern blotting experiments. All seven nonmitochondrial clones sequenced to completion were unique. Nonmitochondrial sequences have a high proportion of unique sites, and very few characters are shared between nonmitochondrial clones to the exclusion of mtDNA. From these data, we infer that fragments of mtDNA have been transposed separately (probably into aphid chromosomes), at a frequency only known to be equalled in humans. The transposition phenomenon appears to occur infrequently or not at all in closely related genera and other aphids investigated. Patterns of nucleotide substitution in mtDNA inferred over a parsimony tree are very different from those in transposed sequences. Compared with mtDNA, nonmitochondrial sequences have less codon position bias, more even exchanges between A, G, C and T, and a higher proportion of nonsynonymous replacements. Although these data are consistent with the transposed sequences being under less constraint than mtDNA, changes in the nonmitochondrial sequences are not random: there remains significant position bias, and probable excesses of synonymous replacements and of conservative inferred amino acid replacements. We conclude that a proportion of the inferred change in the nonmitochondrial sequences occurred before transposition. We believe that Sitobion aphids (and other species exhibiting mtDNA transposition) may be important for studying the molecular evolution of mtDNA and pseudogenes. However, our data highlight the need to establish the true evolutionary relationships between sequences in comparative investigations.   相似文献   
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OBJECTIVE: To compare diagnostic discrepancies and screening parameters between conventional (CP) and ThinPrep (TP) (Cytyc Corporation, Boxborough, Massachusetts, U.S.A.) cervicovaginal samples using Pathfinder (Neopath, Redmond, Washington, U.S.A.). STUDY DESIGN: Pathfinder tracked average screening time, percent slide coverage and percent overlap of viewing fields for CP and TP. False negative rate (FNR) was determined by rescreening 10% of random and high-risk negative cases. CP and TP FNR with Pathfinder were compared to control groups without Pathfinder. RESULTS: A total of 46,393 Pathfinder cases were evaluated (43,354 CP, 3,039 TP) as compared to 62,981 without Pathfinder (60,307 CP, 2,674 TP). FNR was calculated for 12,983 negatives. Using Pathfinder resulted in a significant reduction in FNR for CP atypical squamous cells of undetermined significance and atypical glandular cells of undetermined significance cases. No decrease in FNR was observed for CP squamous intraepithelial lesions or for TP cases. TP slides were screened 66 seconds faster on average than CP. With electronic feedback, mean percent slide coverage and percent overlap were similar between CP and TP cases. Without feedback, coverage dropped and overlap increased slightly for both CP and TP. Technologists screened faster with feedback, saving an average of 50 seconds on CP and 41 seconds on TP. CONCLUSION: Pathfinder significantly reduced FNR for CP but not TP. Technologists screened TP significantly faster than CP while maintaining similar coverage and overlap. Pathfinder feedback itself may decrease screening time.  相似文献   
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Shortly after the initial detection of western flower thrips (WFT), Frankiniella occidentalis (Pergande), in Australia during 1993 a resistance management strategy based on the alternation of chemical groups was implemented. This study aimed to verify this strategy by field testing α-cypermethrin against WFT with and without chemical alternation. Up to 114 times α-cypermethrin resistance (at LC50) was detected and resistance increased with and without chemical alternation; however, chemical alternation did significantly reduce numbers of thrips compared with a nonalternation strategy. Resistance has the potential to undermine the sustainable use of those chemicals to which there is no current detectable resistance. Consequently, chemicals with a high frequency and level of resistance against WFT need to be identified through monitoring and quickly eliminated from WFT chemical control recommendations.  相似文献   
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We developed a new and simple method to collect sections of a whole brown rice kernel for investigation of histological properties. A single kernel of rice was dehydrated through a graded ethanol series, transferred to xylene, and embedded in paraffin. During sectioning of the blocks using a rotary microtome, we used a special adhesive tape to collect and place the sections on slides so they remained flat. The use of the adhesive tape technique combined with autofluorescence characteristics allowed us to visualize cell walls throughout an entire longitudinal or transverse section of a whole rice kernel. We obtained scanning electron microscopy images of the sections to determine section quality.  相似文献   
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Outdoor access is often cited as a critical component of appropriate housing for great apes in captivity, and although studies have shown that offering primates choices can improve welfare, choice to access specific areas has been empirically neglected. Behavioral data were collected on chimpanzees and gorillas housed in naturalistic enclosures while (a) restricted to an indoor enclosure and (b) permitted free access to an adjacent outdoor area. To isolate the factor of choice, only the sessions in which apes remained indoors were compared. With choice, chimpanzees showed more frequent social, F(1, 5) = 20.526, p = .006, and self-directed behaviors, F(1, 5) = 13.507, p = .014, and lower inactivity levels, F(1, 5) = 9.239, p = .029. Gorillas were more frequently inactive, F(1, 8) = 22.259, p = .002, and produced lower levels of object manipulation, F(1, 8) = 8.243, p = .021, and feeding, F(1, 8) = 5.407, p = .049. Results are consistent with an association between choice and the expression of species-typical and arousal behaviors in chimpanzees. The effects are less evident in gorillas, but this outcome may be buffered by the species' lower motivation to utilize the outdoor spaces. Findings highlight species-specific reactions to access to choice that may offer insight for enclosure design, management, and nonhuman animal welfare.  相似文献   
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Background

Diagnostic accuracy of lymphoma, a heterogeneous cancer, is essential for patient management. Several ancillary tests including immunophenotyping, and sometimes cytogenetics and PCR are required to aid histological diagnosis. In this proof of principle study, gene expression microarray was evaluated as a single platform test in the differential diagnosis of common lymphoma subtypes and reactive lymphadenopathy (RL) in lymph node biopsies.

Methods

116 lymph node biopsies diagnosed as RL, classical Hodgkin lymphoma (cHL), diffuse large B cell lymphoma (DLBCL) or follicular lymphoma (FL) were assayed by mRNA microarray. Three supervised classification strategies (global multi-class, local binary-class and global binary-class classifications) using diagonal linear discriminant analysis was performed on training sets of array data and the classification error rates calculated by leave one out cross-validation. The independent error rate was then evaluated by testing the identified gene classifiers on an independent (test) set of array data.

Results

The binary classifications provided prediction accuracies, between a subtype of interest and the remaining samples, of 88.5%, 82.8%, 82.8% and 80.0% for FL, cHL, DLBCL, and RL respectively. Identified gene classifiers include LIM domain only-2 (LMO2), Chemokine (C-C motif) ligand 22 (CCL22) and Cyclin-dependent kinase inhibitor-3 (CDK3) specifically for FL, cHL and DLBCL subtypes respectively.

Conclusions

This study highlights the ability of gene expression profiling to distinguish lymphoma from reactive conditions and classify the major subtypes of lymphoma in a diagnostic setting. A cost-effective single platform "mini-chip" assay could, in principle, be developed to aid the quick diagnosis of lymph node biopsies with the potential to incorporate other pathological entities into such an assay.
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