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71.
The objective of this study was to evaluate endoscopic ultrasound Trucut biopsy (TCB) specimens and compare these findings to fine needle aspiration (FNA) specimens for the diagnosis of neoplasia. FNA and TCB specimens were reviewed in blinded fashion by a cytopathologist from patients (N = 93) who had EUS‐guided FNA and TCB specimens collected between July 2000 and January 2005. Specimens were categorized as nondiagnostic, negative, suspicious for stromal neoplasm, suspicious for malignancy, positive for stromal neoplasm, or positive for malignancy. Standard final diagnosis based on clinical and/or pathologic follow‐up was available for 86 of 93 patients. The final diagnoses comprised malignancy (n = 55), stromal neoplasm (n = 19), and benign findings (n = 12). The combination of FNA and TCB results combined were significantly (P < 0.001) more sensitive that FNA alone for the detection of both malignancy (78% vs. 55%) and stromal neoplasia (79% vs. 19%) without a significant change in overall specificity (92% vs. 100%, P = 1.00). A positive FNA specimen with a negative/nondiagnostic TCB result was established in seven patients with malignancy. A positive TCB diagnosis with a negative/nondiagnostic FNA result was noted in five patients with malignancy. A suspicious FNA result was upgraded to positive in conjunction with TCB specimen evaluation in eight patients with malignancy. The results of this study suggest that TCB is a useful adjunctive technique when used in tandem with FNA for malignancy and stromal neoplasia detection. Additional data are needed to firmly establish practice guidelines for the use of EUS‐guided TCB specimens in clinical practice. Diagn. Cytopathol. 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
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Astroglia is well-known to be integrated in the complex regulation of neuroinflammation in the central nervous system. Astrocytes become activated and synthesize cytokines, chemokines, and prostanoids during degenerative and vulnerable processes and interact with other immune-competent cells. Degenerative disorders often occur in a brain-region-specific fashion suggesting differences in the activity and reactivity of innate immune cells. We have investigated the potency of lipopolysaccharides (LPS) to differently stimulate astrocytes from the cortex and midbrain. Astroglial cultures were prepared from Bagg albino/c mice and exposed to LPS. Astrocytes from both brain areas already differed in their capacity and profile of cytokine expression under basal unstimulated conditions. In response to LPS, we observed both a region-specific pattern of up-regulation of distinct cytokines and differences in the extent and time-course of activation. Our data demonstrate that astrocytes reveal a region-specific basal profile of cytokine expression and a selective area-specific regulation of cytokines upon LPS-induced inflammation. This makes astrocytes likely candidates to be responsible for region-specific incidence rates of neurological and neurodegenerative disorders.  相似文献   
74.

Purpose  

Approximately 8% of couples attempting to conceive are infertile and male infertility accounts for approximately 50% of infertility among couples. Up to 25% of males with non-obstructive infertility have chromosomal abnormalities and/or microdeletions of the long arm of the Y-chromosome. These are detected by conventional chromosome and Y-microdeletion analysis. In this study, we reviewed the results of testing performed in the Mayo Clinic Cytogenetics and Molecular Genetics Laboratories and compared our findings with previously published reports.  相似文献   
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Despite the differences in imaging conditions and the range of approved indications for gadolinium-based contrast agents, the similarities in the structures of these substances have so far resulted in largely similar safety profiles. Nevertheless, some safety-related questions have been raised recently, which indicates that the existing differences in the physicochemical and pharmacokinetic properties of these contrast agents may result in differences in some aspects of the safety profile, in particular for special populations under particular circumstances. An analysis of the current data shows that Gadobutrol and Gadofosveset are well tolerated in the investigated patient populations. Both contrast agents have comparable adverse events profiles.  相似文献   
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Introduction     
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