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Kristine H. Østergaard Ulrik T. Baandrup Tobias Wang Mads F. Bertelsen Johnnie B. Andersen Morten Smerup Jens R. Nyengaard 《Anatomical record (Hoboken, N.J. : 2007)》2013,296(4):611-621
The giraffe heart has a relative mass similar to other mammals, but generates twice the blood pressure to overcome the gravitational challenge of perfusing the cerebral circulation. To provide insight as to how the giraffe left ventricle (LV) is structurally adapted to tackle such a high afterload, we performed a quantitative structural study of the LV myocardium in young and adult giraffe hearts. Tissue samples were collected from young and adult giraffe LV. Design‐based stereology was used to obtain unbiased estimates of numbers and sizes of cardiomyocytes, nuclei and capillaries. The numerical density of myocyte nuclei was 120 × 103 mm?3 in the adult and 504 × 103 mm?3 in the young LV. The total number (N) of myocyte nuclei was 1.3 × 1011 in the adult LV and 4.9 × 1010 in the young LV. In the adult LV the volume per myocyte was 39.5 × 103 µm3 and the number of nuclei per myocyte was 4.2. The numerical density of myocytes was 24.1 × 106 cm?3 and the capillary volume fraction of the adult giraffe ventricle was 0.054. The significantly higher total number of myocyte nuclei in the adult LV, the high density of myocyte nuclei in the LV, and the number of nuclei per myocyte (which was unusually high compared to other mammalian, including human data), all suggest the presence of myocyte proliferation during growth of the animal to increase wall thickness and normalize LV wall tension as the neck lengthens and the need for higher blood pressure ensues. Anat Rec, 296:611–621, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
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T. C. EL‐GALALY S. R. KRISTENSEN K. OVERVAD R. STEFFENSEN A. TJØNNELAND M. T. SEVERINSEN 《Journal of thrombosis and haemostasis》2012,10(10):2191-2193
See also Lowe GDO. Epidemiology of venous thromboembolism: the need for large (including prospective) studies and meta‐analyses. This issue, pp 2186–8 and Rosendaal FR. Etiology of venous thrombosis: the need for small original studies. This issue, pp 2189–90. 相似文献
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Makio Kusaoi Ken Yamaji Go Murayama Misa Yasui Risa Yamada Ruka Hishinuma Takuya Nemoto Katsura Hohtatsu Michiaki Kageyama Toshio Kawamoto Kaoru Sugimoto Fumio Sekiya Takayuki Kon Michihiro Ogasawara Kazuo Kempe Hiroshi Tsuda Yoshinari Takasaki 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2012,16(5):456-466
Leukocytapheresis (LCAP) is a safe, unique therapy pertaining to intractable rheumatoid arthritis (RA) even in cases of drug allergy or infectious states. To investigate how to represent LCAP efficacy, we have conducted gene expression analyses from the peripheral blood of RA patients treated with non‐woven polyethylene terephthalate filters. Peripheral blood samples were collected immediately before and after treatment from eight RA patients who received LCAP. Among these patients, all of them achieved 20% improvement in the core set of the American College of Rheumatology (ACR20), and thus, they were confirmed as LCAP responders. Gene expression analysis was done with a high‐resolution DNA microarray. The results of each of the two groups' gene expression values (immediately before and after LCAP) were calculated using Welch's t‐test. Calculations were performed with a statistical software R.basic package: if the P‐value was less than 0.05, this was seen as a significant change. In a comparison of 25 370 gene expressions, the number of genes showing a P‐value < 0.05 in the upregulating group was 2110, and in the downregulating group it was 1864. The results of pathway analysis using the MetaCore program indicate that gene groups work for cytoskeletal remodeling are upregulated, and genes related to immune responses, such as antigens presenting via major histocompatibility complex class I and II, are downregulated just after LCAP. These findings may relate to LCAP efficacy for RA patients, but this needs further investigation. 相似文献
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Study findings challenge the content validity of the Canadian Consensus Criteria for adolescent chronic fatigue syndrome
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