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21.
An inhalation technique was used for anesthesia during ileal cannulation in five adult cows. Following sedation with intravenous acepromazine, anesthesia was induced intravenously with thiopental sodium in 5% glyceryl guaiacolate solution. Endotracheal intubation was performed and anesthesia maintained with halothane in oxygen via a circle system with a precision vaporizer. In all cases, induction was smooth and no difficulties were experienced during the maintenance of anesthesia. Total anesthesia time was 1.5 to 2.5 hours. Following completion of the surgical procedure, which was performed with the animal in left lateral recumbency, each cow was rolled to a sternal position and supported, if necessary. The endotracheal tube was left in place, with oxygen administration continued, until the animal was able to swallow. Recoveries were rapid and all animals were ambulatory within 30 minutes after completion of the surgery. The only post-operative complication due to anesthesia was transient mouth soreness in two cases, attributed to the use of a mouth speculum during intubation.  相似文献   
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Electron transport system (ETS) activity, CO2 evolution, O2 consumption, N2-fixation (C2H2 reduction) and methanogenesis were appropriately measured in aerobic and anaerobically incubated sediment at 4, 10 and 20 ° C to better characterize these activities under different incubation conditions. ETS activity was always higher in the aerobically incubated sediment at all three incubation temperatures, whereas (C2H2 reduction was always greater in the anaerobic sediment. Carbon dioxide evolution was detected only in the aerobic sediment at 10 and 20 ° C but not at 4 ° C. Methane evolution in anaerobic sediment increased gradually with an increase in the incubation temperature.  相似文献   
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A case of choriocarcinoma metastatic to the lung following a previous hydatidiform mole is presented. It was possible to make definitive identification of trophoblastic elements on a needle aspiration biopsy using an immunoperoxidase staining technique, thus avoiding diagnostic thoracotomy prior to therapeutic intervention. A method of immunoperoxidase staining of previously fixed and Papanicolaou-stained needle aspiration biopsy specimens is also described, and other uses of the immunoperoxidase technique on needle biopsy specimens are discussed.  相似文献   
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An apparently new type of dental wear pattern, lingual surface attrition of the maxillary anterior teeth (LSAMAT), has been found in 85% of 46 adult crania from a 3000–4200 BP Archaic site called Corondó near the Atlantic Ocean coast of Brazil. LSAMAT is associated with a high caries rate (60% of 77 adults; 11% of 1,219 permanent teeth) in what on archeologica grounds alone would be considered a mainly meat-eating population. It is suggested that both LSAMAT and caries resulted from eating some starchy plant like manioc.  相似文献   
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Assays of plasma levels of 25-hydroxyvitamin D are widely used to assess vitamin D nutrition in health and disease. In interpreting the results it is important to take into account not only details of analytical technique but also environmental conditions including latitude, season, occupation and weather. This paper presents new data which show that climatic variations from year to year may make appreciable differences to the reference ranges which are appropriate for the interpretation of results from patients.  相似文献   
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Nine independent pigeon cytochrome c-specific T cell clones were analyzed by using a panel of antigenic peptide analogs presented in association with three allelic IE-encoded MHC glycoproteins. Eight of the T cell clones expressed a TCR composed of a unique alpha- and beta-chain amino acid sequence, and concordantly, each of these T cell clones exhibited a unique Ag specificity. This was true for several clones which differed only in TCR V-J junctional regions. Interestingly, for a given clone, the response to some of the peptide analogs depended to a large extent on the allelic form of the presenting MHC molecule. A simple interpretation of these data would suggest that certain positions of the peptide Ag are most important for Ag-MHC molecule interactions, and that these specific interactions can influence the antigenic epitope recognized by the TCR. We suggest that an antigenic peptide binds to an MHC glycoprotein in a distinct way, but may retain a measure of flexibility.  相似文献   
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Six clonotypically unique T cell hybridomas from Lewis rats were used to study accessory cell activities required for class II MHC restricted T cell responses to the 68-86 encephalitogenic sequence of myelin basic protein (MBP). T cell hybrids which were cultured with GP68-86 68-86 sequence of guinea pig MBP (GPMBP) and naive splenocytes (SPL) were induced to produce IL-2 as measured by the CTLL indicator cell line. The hybrids were categorized into two subsets (designated THYB-1 and THYB-2), because two distinct subset-specific pathways of communication between accessory cells and T cells were involved in GPMBP-induced IL-2 production. These pathways were distinguished by the following six observations. First, when the duration of a pulse of SPL with GPMBP was lengthened from 1 to 4 h, these SPL lost their ability to induce IL-2 production by THYB-2 hybrids yet nevertheless retained full stimulatory activity for THYB-1 hybrids. Second, paraformaldehyde fixation of GPMBP-pulsed SPL abrogated an activity necessary for Ag-induced IL-2 production by THYB-2 hybrids. These fixed SPL were nevertheless able to stimulate THYB-1 hybrids, albeit to a lesser extent than viable unfixed SPL. Third, the addition of either cycloheximide, cytochalasin B, or 2-deoxyglucose to an Ag pulse of SPL with GPMBP dramatically inhibited the subsequent responses of THYB-2 hybrids yet had little or no effect upon the reactivity of THYB-1 hybrids. Fourth, thymocytes lacked necessary activities for GPMBP evoked IL-2 production by THYB-2 hybrids yet strongly promoted THYB-1 hybrid responses. Fifth, exposure of SPL to as little as 500 rad of gamma-irradiation markedly attenuated THYB-2 hybrid response to GPMBP but did not affect THYB-1 responses. Sixth, anti-GPMBP responses by THYB-2 hybrids were observed only in the presence of both radioresistant adherent SPL and a distinct population of radiosensitive nonadherent SPL. Conversely, THYB-1 hybrids exhibited full reactivity to GPMBP in the presence of adherent radioresistant SPL. Together, these observations reveal that two distinct accessory cell-T cell pathways mediate immune recognition of the 68-86 encephalitogenic region of MBP. Furthermore, these results indicate that subsets of Th cells can be defined by the accessory cell type-specific interactions that are necessary for Ag-mediated responses.  相似文献   
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