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21.
The capacities of BSA and DNP—protein conjugates to evoke reagin formation in rabbits were compared. Reagins to DNP generally appeared earlier and disappeared more rapidly from the circulation than did anti-BSA reagins. Initial formation of reagins proceeded with a logarithmic phase indicating a doubling time of 7–8 hours. Booster antigen injections resulted in some cases in a reagin response after a shorter latent phase than that observed after primary immunization. A secondary reagin response was more readily evoked in rabbits with low titres of agglutinating antibodies than in those with high titres. Anti-DNP reagins were demonstrable in a higher percentage of the injected rabbits than were anti-BSA reagins. The two types of reagins were equally sensitive to heat and 2-mercaptoethanol. A positive correlation between serum levels of anti-DNP but not anti-BSA reagins and agglutinating antibodies was demonstrated. Some evidence that a low antigen dose was more efficient than a high dose in evoking reagin formation was obtained. Treatment of rabbits with 6-mercaptopurine during the 1st week following antigen injection resulted in an increased latent phase and an enhancement of the production of anti-BSA reagins and some suppression of the formation of anti-DNP reagins.  相似文献   
22.
Objectives. The aims of the study were to examine the reliability of the Dutch and French versions of the Tampa scale kinesiophobia (TSK) version chronic fatigue syndrome (CFS), and to examine the reliability and validity of the Dutch and French versions of the CFS symptom list. Design. Repeated‐measures design. Methods. Native Dutch speakers (N=100) and native French (N=48) speakers fulfilling the diagnostic criteria for CFS were asked to list the five most important symptoms and to complete the TSK–CFS, the CFS symptom list, and the Short Form 36 Health Status Survey or SF‐36. A modified version of the TSK–CFS and the CFS symptom list was filled in within 24 hours of the first assessment. Results. The French and Dutch version of the TSK–CFS and CFS symptom lists displayed good reliability (ICC≥.83). The CFS symptom list was internally consistent (Cronbach's α≥.93) and concurrently valid with the SF‐36. For the native Dutch and French speakers, respectively, 82 and 78% of the self‐reported symptoms matched the content of CFS symptom list. Conclusions. The results are in support of the psychometric properties of the French and Dutch versions of both the TSK–CFS and the CFS symptom list for assessing kinesiophobia and symptom severity, respectively.  相似文献   
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采用“家长生活调查问卷”对广州市就读专收HAA阳性幼儿园的父母、未有就读任何幼儿园HAA阳性儿童的父母、以及就读普通幼儿园健康儿童父母进行了调查,结果发现HAA阳性儿童的父母由于承受较大的心理压力而出现更多的心理问题、这种压力影响到父母的身心健康。资料为社会保健提供了依据。  相似文献   
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Diethylstilbestrol (DES) treatment of a male Syrian hamster resulted in the development of a renal tumor and its widely scattered scrosal metastases. Cells in both the primary tumor and metastatic nodules contained secretory granules. The tumors were transplanted serially into DES-supported and non-DES-supported host hamsters until DES-independent tumors developed. Rabbit antiserum to mouse salivary renin and rabbit antiserum to rat kidney resin were reacted with sections of the primary tumor, metastatic nodules, and all transport tumors. The sections were stained by the PAP and Vector-ABC-AP procedures. Renin-positive material was observed in all tumors. Plasma renin activity (PRA) was determined for the host hamsters carrying the renal tumor transplants and compared to the PRA values that had been determined for normal non-DES-treated male and female hamsters. It was found that the average PRA values of host hamsters carrying the tumor transplants were significantly higher than the normal PRA ralues.  相似文献   
27.
Vesicular stomatitis virus (VSV), when reproduced in human tumor cell lines, assembled a specific subset of cell-derived proteins. These were detected by [35S]methionine labeling of cells prior to infection and subsequent immunoprecipitation of VSV grown in these cells, as well as by direct immunoprecipitation of labeled cell extracts with antiserum directed against the VSV-assembled proteins. Their molecular weight (Mr) ranged between 15K and 180K; the larger proteins were glycosylated. Two of the major protein species (gp88 and gp130) were common to all four cell lines used (HeLa—cervical carcinoma, T47D—breast carcinoma, and HMB2 and SK1477—two melanoma cell lines). Proteins of other molecular weights were detected only in one or two of the cell lines. The melanoma cell lines (even in the absence of VSV) shed large particulate material which had contained the same spectrum of proteins that were assembled by VSV. The major protein component had an Mr of 30K. Some of the VSV-assembled proteins might possibly serve as specific tumor markers. It is also conceivable that the proteins assembled by VSV as well as the large particulate material might be products of defective endogenous human retroviruses.  相似文献   
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29.
We have previously demonstrated that p100H mutant mice, which lack a functional Sox6 gene, exhibit skeletal and cardiac muscle degeneration and develop cardiac conduction abnormalities soon after birth. To understand the role of Sox6 in skeletal muscle development, we identified muscle-specific genes differentially expressed between wild-type and p100H mutant skeletal muscles and investigated their temporal expression in the mutant muscle. We found that, in the mutant skeletal muscle, slow fiber and cardiac isoform genes are expressed at significantly higher levels, whereas fast fiber isoform genes are expressed at significantly lower levels than wild-type. Onset of this aberrant fiber type-specific gene expression in the mutant coincides with the beginning of the secondary myotube formation, at embryonic day 15-16 in mice. Together with our earlier report, demonstrating early postnatal muscle defects in the Sox6 null-p100H mutant, the present results suggest that Sox6 likely plays an important role in muscle development.  相似文献   
30.
The isthmo-optic nuclei (ION) and ectopic neurons, which constitute the centrifugal visual system (CVS), are thought to be cholinoceptive and nitrergic. However, it is not clear which neurons express these markers, namely the ones that project to the retina rather than in neurons that only participate in a local circuit. Therefore, to characterize the neurochemical patterns of the centrifugal visual system in the post-hatched chick, retinopetal cells of the isthmo-optic nuclei and the ectopic region were identified via immunolabeling for cholera toxin, a neuronal tracer, which has been injected in the ocular globe. Then, double labeled with acetylcholinesterase histochemistry to reveal cholinergic synapses, or NADPH-diaphorase histochemistry as a nitrergic marker. Briefly, acetylcholinesterase activity was present mainly in cholera toxin labeled cell bodies of the isthmo-optic nucleus and the ectopic region indicating that retinal projecting neurons of centrifugal visual system comprise a cholinoceptive pathway. On the other hand, NADPH-diaphorase histochemistry was present in the neuropile and sparse cell bodies inside of the isthmo-optic nucleus and in ectopic neurons which were not cholera toxin positive suggesting their role in an intrinsic circuit of the centrifugal visual system. These data support the idea that these two neurochemical systems are present in distinct neuronal populations in the centrifugal visual system.  相似文献   
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