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The role of the vertebral arteries in delaying loss of sensibility following neck sticking in slaughter calves was investigated. Vertebral artery blood flow was measured using probes before, during and after electrical stunning and slaughter. Systemic blood pressure, electrocorticogram, visually evoked responses and the occurrence of carotid occlusions were also recorded. When carotid occlusion occurred, the time to onset of brain failure was delayed based on the development of an isoelectric state. In addition, when carotid occlusion occurred the mean arterial blood pressure was sustained for longer following slaughter, and concurrently vertebral artery blood flow could be maintained at about 30% of its initial level for up to 3 min. In some animals vertebral artery flow increased substantially following sticking. When chest sticking was used no occlusion of vessels occurred, mean arterial blood pressure fell promptly (within 8 s) and the onset of an isoelectric state did not extend beyond one minute. In addition, visually evoked responses were not present after 5 s following chest sticking. 相似文献
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Purpose : Zilongjin, a complementary Chinese herbal medicine, has been used to alleviate the adverse effects of chemotherapeutic drugs in cancer therapy. However, the mechanisms of anti‐cancer activity of Zilongjin are still largely unkonwn. Experimental design : First, the proteomic approach of combined 2‐DE and ESI‐MS/MS was used to investigate the effect of Zilongjin on the protein expression in MCF‐7 cells. Then, the differential expression of some proteins was confirmed by Western blot, cytoimmunofluoresecnce, and quantitative real‐time RT‐PCR analysis. Results : The identified proteins with differential expression, involved in such events as protein translation, cellular signal transduction, cytoskeleton formation and transportation, include seven downregulating proteins, such as Eukaryotic translation initiation factor 3 subunit I, Eukaryotic translation initiation factor 1A Y‐chromosomal, Ran‐specific GTPase‐activating protein, Ubiquitin‐conjugating enzyme E2 N, Tropomodulin‐3, Macrophage‐capping protein, and Tumor protein D52, as well as two upregulating proteins, HSP β‐1 and keratin18. Moreover, the differential expression of three proteins was confirmed. Conclusions and clinical relevance : (i) These results provide a new insight into the molecular mechanisms of Zilongjin on therapy for breast cancer. (ii) The application of the proteomic approaches will result in the more extended appreciation of Chinese medicine than those known at present. 相似文献
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Nelsestuen GL Harvey SB Zhang Y Kasthuri RS Sinaiko AR Ely EW Bernard GR Homoncik M Jilma B 《Proteomics. Clinical applications》2008,2(2):158-166
Although numerous protein biomarkers have been correlated with advanced disease states, no new clinical assays have been developed. Goals often anticipate disease-specific protein changes that exceed values among healthy individuals, a property common to acute phase reactants. This review considers somewhat different approaches. It focuses on intact protein isoform ratios that present a biomarker without change in the total concentration of the protein. These will seldom be detected by peptide level analysis or by most antibody-based assays. For example, application of an inexpensive method to large sample groups resulted in observation of several polymorphisms, including the first structural polymorphism of apolipoprotein C1. Isoform distribution of this protein was altered and was eventually linked to increased obesity. Numerous other protein isoforms included C- and N-terminal proteolysis, changes of glycoisoform ratios and certain types of sulfhydryl oxidation. While many of these gave excellent statistical correlation with advanced disease, clinical utility was not apparent. More important may be that protein isoform ratios were very stable in each individual. Diagnosis by longitudinal analysis of the same individual might increase sensitivity of protein biomarkers by 20-fold or more. Protein changes that exceed the range of values found among healthy individuals may be uncommon. 相似文献
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Huang CP Liu YT Nakatsuji T Shi Y Gallo RR Lin SB Huang CM 《Proteomics. Clinical applications》2008,2(9):1234-1245
Proteomics is a powerful tool for the identification of proteins, which provides a basis for rational vaccine design. However, it is still a highly technical and time‐consuming task to examine a protein's immunogenicity utilizing traditional approaches. Here, we present a platform for effectively evaluating protein immunogenicity and antibody detection. A tetanus toxin C fragment (Tet‐c) was used as a representative antigen to establish this platform. A cell wall‐anchoring sialidase‐like protein (SLP) of Propionibacterium acnes was utilized to assess the efficacy of this platform. We constructed an Escherichia coli vector‐based vaccine by overexpressing Tet‐c or SLP in E. coli and utilized an intact particle of E. coli itself as a vaccine (E. coli Tet‐c or SLP vector). After ultraviolet (UV) irradiation, the E. coli vector‐based vaccines were administered intranasally into imprinting control region mice without adding exogenous adjuvants. For antibody detection, we fabricated antigen microarrays by printing with purified recombinant proteins including Tet‐c and SLP. Our results demonstrated that detectable antibodies were elicited in mice 6 weeks after intranasal administration of UV‐irradiated E. coli vector‐based vaccines. The antibody production of Tet‐c and SLP was significantly elevated after boosting. Notably, the platform with main benefits of using E. coli itself as a vaccine carrier provides a critical template for applied proteomics aimed at screening novel vaccine targets. In addition, the novel immunogenic SLP potentially serves as an antigen candidate for the development of vaccines targeting P. acnes‐associated diseases. 相似文献
8.
High temperature faraday balance for in situ measurement of magnetization in transition metal oxides
We report the design of a Faraday balance that can be used to measure the magnetization of transition metal oxides at high temperatures and under controlled atmosphere. The instrument is sufficiently sensitive and stable to quantify the magnetic force on diamagnetic and paramagnetic samples at temperatures up to 1000 degrees C and in oxygen partial pressures as low as 100 ppm. We demonstrate the performance of the instrument by presenting preliminary magnetic measurements of lanthanum strontium cobalt oxide (La1-xSr(x)CoO3-delta) and aluminum oxide (Al2O3). 相似文献
9.
Chang SH Park SB Cho GH 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》1993,40(3):216-223
The quadrature sampling technique as a means of detecting the envelope of RF waveform in the baseband is well known. If this technique is applied to a focused ultrasound imaging system using an array transducer, whether it is a synthetic or nonsynthetic focusing system, unwanted phase terms appear in the expressions of the inphase and quadrature components of the baseband signal when an appropriate delay time is introduced to each channel signal for the purpose of focusing. The expressions of the inphase and quadrature components from the point of focusing are derived and analyzed in detail, and a scheme to eliminate the unwanted phase terms is proposed. The resulting phase-error-free quadrature sampling technique is applied to the synthetic focusing system; a system block diagram together with the simulation and experimental results are presented. 相似文献
10.
Curtis SB 《Radioprotection》1993,28(2):179-181
The risk from exposure to radiation posed to space travelers outside the magnetic shielding provided by the geomagnetosphere will come from two sources: the slowly varying but low intensity high-energy galactic cosmic rays and the more intense predominantly low-energy protons from large solar particle events associated with magnetic disturbances originating sporadically on or within the solar surface during the active period of the 11-year solar cycle. The energy spectra of the protons in solar particle events are quite soft, with large numbers of low-energy protons and a rather steep decrease of the energy spectra with increasing energy. This allows for the possibility to provide, within the space vehicle or habitat, a well-shielded area sometimes called a "storm shelter" or "safe haven" where the travelers could gather during the largest particle events. Intensity risetimes on the order of half an hour or more and overall event durations of 1 to 2 days would make actively seeking a well-shielded shelter for the duration a distinct possibility. The high-energy and penetrating nature and relative constancy of the galactic cosmic rays, on the other hand, do not allow the use of highly shielded areas as a means of protection against them. The first question to answer becomes: what is the risk to human health from the galactic cosmic rays? We need to have a good idea of the answer to this question before we can address the problem of how to best protect human health or, indeed, whether any specific measures need to be taken. 相似文献