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71.
Methods are described for rearing large quantities of Ditylenchus dipsaci on alfalfa tissues. Nematodes and alfalfa seed were disinfected and nematodes were reared in quantities sufficient to provide a continuous supply of inoculum for our alfalfa-breeding program. Nematodes reproduced best in darkness at 20-25 C. Cultures reached maximum numbers in 3-6 wk. 相似文献
72.
CR Taylor 《Biotechnic & histochemistry》2014,89(6):419-423
The traditional microscope, together with the “routine” hematoxylin and eosin (H & E) stain, remains the “gold standard” for diagnosis of cancer and other diseases; remarkably, it and the majority of associated biological stains are more than 150 years old. Immunohistochemistry has added to the repertoire of “stains” available. Because of the need for specific identification and even measurement of “biomarkers,” immunohistochemistry has increased the demand for consistency of performance and interpretation of staining results. Rapid advances in the capabilities of digital imaging hardware and software now offer a realistic route to improved reproducibility, accuracy and quantification by utilizing whole slide digital images for diagnosis, education and research. There also are potential efficiencies in work flow and the promise of powerful new analytical methods; however, there also are challenges with respect to validation of the quality and fidelity of digital images, including the standard H & E stain, so that diagnostic performance by pathologists is not compromised when they rely on whole slide images instead of traditional stained tissues on glass slides. 相似文献
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The field of regenerative medicine (RM) faces many challenges, including funding. Framing the analysis in terms of institutional politics, valuation studies and “technologies of knowledge”, the paper highlights growing debates about payment for RM in the UK, setting this alongside escalating policy debates about “value”. We draw on interviews and publicly available material to identify the interacting and conflicting positions of institutional stakeholders. It is concluded that while there is some common ground between institutional stakeholders such as industry and health system gatekeepers, there is significant conflict about reward systems, technology assessment methodologies and payment scenarios; a range of mostly conditional payment schemes and non-mainstream routes are being experimented with. We argue that current developments highlight a fundamental conflict between a concern for the societal value of medical technologies in a resource-limited system and a concern for engineering new reward and payment models to accommodate RM innovations. 相似文献
79.
By the age of 80 yr, the skeletal muscles of men and women decrease in mass and maximum force by approximately 30%. Severe contraction-induced injury may contribute to these age-related declines. One to two months after a 225 lengthening contraction protocol (LCP), muscles of young/adult male mice recovered completely, whereas those of old male mice sustained deficits of approximately 15% in mass and approximately 25% in maximum force. Although gender-related differences in the early events of contraction-induced injury have been reported, the recovery phase of muscles in old female animals has not been investigated. The hypothesis tested was that 2 mo after a severe LCP to the plantar flexor muscle group, the magnitude of recovery of mass and force for old female mice is less than that for adult female mice. The LCP was administered to muscles of adult and old, female C57BL/6 mice. At 3 days, 1 mo, and 2 mo following the LCP, maximum isometric force was measured, and muscles were removed and weighed. Two months following the LCP, the muscles of adult female mice recovered mass and force. In contrast, for old female mice, even after 2 mo, muscle masses were decreased by 11% and maximum forces by 38%. We conclude that, as reported previously for old male mice, a severe contraction-induced injury to muscles of old female mice results in prolonged deficits in mass and force. 相似文献
80.
E D Harris C S Faulkner S Wood 《Biochemical and biophysical research communications》1972,48(5):1247-1253
Collagenolytic enzyme activity has been found in high levels in homogenates of a tumor (ascitic V2 carcinoma) implanted in rabbit muscle. Unlike other mammalian collagenases, this enzyme was not actively synthesized and released by primary cultures of the tumor. Most of the collagenolytic activity in tumor homogenates was found to sediment at 1000–4000 × g along with 5′-nucleotidase activity indicating that it might be bound to a membraneous component of the cell. 相似文献