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41.
AIM:To determine the role of CD133 in cholangiocarcinoma progression. METHODS:CD133 protein expression was evaluated by immunohistochemistry in 34 cholangiocarcinoma specimens.In addition,proliferation,chemoresistance and invasive properties of CD133-enriched(CD133 + ) and CD133-depleted(CD133 )RMCCA1 cholangiocarcinoma cells were studied and compared. RESULTS:Strong CD133 expression was observed in 67.6%(23/34)of the cholangiocarcinoma specimens. Strong expression of CD133 was significantly associated with...  相似文献   
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The eggs of Anopheles argyropus, Anopheles crawfordi, Anopheles nigerrimus, Anopheles nitidus, Anopheles paraliae, Anopheles peditaeniatus, Anopheles pursati, and Anopheles sinensis are described with the aid of scanning electron micrographs. Comparisons of the egg structure among the eight species showed that the eggs differed with respect to the following characteristics: the deck—complete (An. argyropus, An. nigerrimus, An. paraliae, An. peditaeniatus, and An. sinensis); variable (complete, split and incomplete decks found together within an egg batch/An. crawfordi); and division into an area at each end (An. nitidus and An. pursati). The ratios of the entire length per maximal deck width within the area covered by floats were 3.33–6.86 (An. sinensis), 8.78–18.20 (An. peditaeniatus), 13.67–22 (An. nigerrimus), 26.33–44.25 (An. paraliae), and 26.99–75.94 (An. argyropus). The numbers of float ribs were 21–27 (An. peditaeniatus) and 28–34 (An. nigerrimus), and the total numbers of anterior and posterior tubercles were 6–8 (An. paraliae) and 9–11 (An. argyropus). Exochorionic sculpturing was of reticulum type (An. argyropus, An. crawfordi, An. nigerrimus, An. nitidus, An. paraliae, An. peditaeniatus, and An. sinensis) and pure tubercle type (An. pursati). Attempts are proposed to construct a robust key for species identification based on the morphometrics and ultrastructures of eggs under scanning electron microscopy.  相似文献   
44.
A new type of rodent babesia, which resembled Babesia microti but was phylogenetically placed closest, with the highest level of statistical support, to Babesia canis, a canine babesia, was identified in Thai Bandicota indica in Thai provinces to which malaria is endemic. Close watch should be kept on human babesiosis in Thailand.  相似文献   
45.
Adenocarcinoma is a type of cancer that occurs in the glandular cells throughout the body. There are several metastatic adenocarcinoma of unknown primary origin. Currently, there is no highly effective method to differentiate pancreatic ductal adenocarcinoma (PDAC) from other adenocarcinomas. Here, we identified pancreas tissue by site‐specific methylation at FRY and found that it can also detect PDAC. The establishment of Combined Bisulphite Restriction Analysis (COBRA) and quantitative real‐time PCR techniques of FRY revealed FRY hypermethylation in 21 out of 24 normal pancreatic tissue samples, whereas all other normal tissue samples from thirteen other organs (80 samples) remained totally unmethylated. Similarly in application to PDAC, this marker effectively indicated 25 PDAC among 151 other common adenocarcinomas with values of 100%, 98.7%, 92.6%, and 100% in sensitivity, specificity, positive predictive value and negative predictive value, respectively. In summary, we have demonstrated that this epigenetic site‐specific marker has high potential for pancreatic tissue identification and can be applied in PDAC diagnosis.  相似文献   
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At least three members (species A, C, and E) of the Anopheles minimus complex have been described in the Orient. This study investigated the specific status of An. minimus collected in the southern part of Taiwan by crossing experiments with species A from Thailand and species E from Japan. Crosses between Taiwan An. minimus and species A revealed genetic compatibilities. Post-zygotic isolation was observed in crosses between Taiwan An. minimus and species E. Hybrid progeny were only obtained from Taiwan female X species E male. F2 hybrid progeny were not obtained, since the hybrid males were sterile or almost sterile, with atrophied testes or abnormal spermatozoa. The hybrid females backcrossed with either Taiwan F1 progeny and species E males, and laid eggs with lower fertility and viability. This study supports previous published data regarding the analysis of the D3 region of the 28S gene of ribosomal DNA that An. minimus species A is indigenous to Taiwan. Whether other members of the An. minimus complex exist in Taiwan is not conclusive and needs more study.  相似文献   
48.
Background: A phenomenon of ‘preconditioning’ exists for the heart, but has not been described for the liver. This study was undertaken to determine whether a brief episode of ischaemia (3 or 5 min) followed by a short reperfusion time (5 or 10 min) would precondition the liver to reduce subsequent injury from prolonged ischaemia (30 to 90 min). Methods: Male Wistar rats were allocated into five control (no preconditioning) and five preconditioned groups, each having a liver resection. The preconditioning times were 3 rnin ischaemia followed by 5 rnin reperfusion with a prolonged ischaemia of 60 or 90 min for the first two groups, and 5 min ischaemia followed by 10 rnin reperfusion with prolonged ischaemia times of 30 or 45 min for the other three groups. Results: Of rats resected with 3–5–60 rnin time sequence designed to assess survival, 9/10 died. However 9/10 died also in the matching control group with 60 rnin ischaemia. With a 5–10–45 rnin sequence, 9/10 survived more than 24 h in the preconditioned group and 1/10 in the non-preconditioned controls. With a 5–10–30+ sequence designed to measure liver function tests, the prothrombin time was significantly improved; bilirubin, serum alkaline phosphatase and the alanine aminotransferase improved but these did not reach significance. Conclusion: A brief episode of ischaemia followed by an episode of reperfusion before a prolonged period of ischaemia ameliorated the effects of ischaemia-reperfusion injury in a rat liver resection model. If hepatic preconditioning is confirmed in humans, ischaemic preconditioning will have an important role for all liver surgery.  相似文献   
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Background

Assessment of HER2 status is considered standard of care in the histopathologic workup of breast cancer and conveys prognostic and predictive information used to guide treatment decisions. The assessment is often carried out in a two-step approach where immunohistochemical expression of HER2 protein is first evaluated by conventional microscopy and equivocal cases are further analyzed by in-situ hybridization techniques to assess gene amplification status. In this study we compared conventional manual assessment of immunohistochemical HER2 expression with digital image analysis (DIA) and consensus manual assessment by a panel of three pathologists.

Methods

From our archive we retrieved sections of 109 invasive breast carcinomas stained for HER2 with corresponding HER2 score from the original pathology report. The glass slides were assessed by three pathologists to reach a consensus score. Next, the slides were scanned into whole slide images and DIA was performed using Aperio Imagescope. The scoring results were then compared with gene amplification status evaluated by dual in-situ hybridization (DISH).

Results

Comparing manual assessment with consensus assessment and DIA, good agreement was obtained with weighted kappa coefficients of 0.79 (manual vs. consensus) and 0.67 (manual vs. DIA). When compared with gene status assessment by DISH, agreement analysis yielded weighted kappa coefficients of 0.52 (manual vs. DISH), 0.58 (consensus vs. DISH) and 0.78 (DIA vs. DISH). There were no false negatives by any of the three methods and false positives ranging from 0.9 to 2.8%. The proportion of equivocal cases by each method was 44% (manual), 33.3% (consensus) and 14.7% (DIA). Application of DIA reduced the number of equivocal cases by 67% without increasing the proportion of false negatives.

Conclusion

We conclude that DIA is an accurate method to reduce the number of HER2 equivocal cases without affecting the sensitivity of the HER2 assessment.  相似文献   
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