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91.
Keith D. Allen William J. Warzak Nancy G. Greger Toni D. Bernotas Carol A. Huseman 《Children's Health Care》1993,22(1):61-72
Fifty-six children with isolated growth hormone deficiency (IGHD) and their families completed self-report instruments about behavioral, social, and emotional adjustment of the children. Results show that children with IGHD may experience significant behavioral and social adjustment problems. Social and emotional adjustment was best predicted by the relative height discrepancy between an individual and their normal-sized peers. Adjustment varied depending on the type of adjustment under consideration, the relative height discrepancy of the individual, the age and gender of the child, and the amount of time in treatment. Discussion addresses the need for an interdisciplinary approach to effective patient management of children with IGHD. 相似文献
92.
Oral mucosal reactions to cinnamon-flavored chewing gum 总被引:1,自引:0,他引:1
Oral lesions induced by contact with cinnamon flavoring agents are relatively uncommon, and are probably unrecognized as such by many clinicians. Ten patients with these lesions seen during the past 6 years are described in this report. Most patients had a "burning sensation" as their primary symptom. Clinically, lesions appeared as erythematous patches with varying degrees of superimposed keratosis or ulceration, or both. The lesions were usually confined to the buccal mucosa and lateral border of the tongue. The offending agent was almost always cinnamon-flavored chewing gum, and symptoms typically resolved within 1 to 2 days of discontinuing the product containing cinnamon. 相似文献
93.
Monocytes and other infiltrating cells in human colorectal tumours identified by monoclonal antibodies 总被引:1,自引:0,他引:1 下载免费PDF全文
Monoclonal antibodies have been used to examine the patterns of infiltrating cells in colorectal tumours staged according to Dukes' classification. MAbs reacting with monocytes, but not tissue Mph, revealed a six-fold increase in monocytes in metastasizing C tumours compared to normal gut. The non-metastasizing B tumours could be divided into one group containing increased numbers of monocytes, and a second group comparable to control gut. T-cell numbers were increased in all tumour stages by an average 1.4-fold, which disguised the lack of consistent pattern in T-cell subset ratios in the tumour stromal tissue. However, in the tumour epithelium, there was a constant decrease in the Ts + c cell subset and a subsequent alteration in T-cell subset ratio in favour of Th + i cells. With the progression from Dukes' Stage B to C, there was an increase in the proportion of monocytes and T cells which were activated as detected by mAbs to the C3b receptor and IL-2 receptor, respectively. These observations suggest that an immune response is in progress in these colorectal tumours and that it is most active in the metastasizing Dukes' C tumours. Whether this response is elicited by the tumour or other elements, whether it is detrimental to tumour growth, or whether it is actively assisting tumour growth and possibly dissemination, are matters of conjecture. 相似文献
94.
W. Walz A. F. Allen 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1987,68(2):290-298
Summary Homogenous primary cultures of mouse astrocytes and cortical neurons were used to clarify the role of taurine in ion and osmoregulation in the CNS. This study indicates that both neurons and glial cells have uptake systems for taurine. The cell water content does not change during loading of cells with taurine. Chemical analysis indicates that part of the accumulated taurine is metabolized and that the product(s) are stored in the cells. Extracellular taurine (1 mM) has no effect on K+, Na+, Cl-, or Ca2+ movements in astrocytes. However, astrocytes loaded to a taurine content which corresponds a concentration of 60 mM (corresponds to normal mouse cortex levels) show a 50% reduction in their K+ accumulation by carriers and a 100% increase in Ca2+ turnover rates. Movements of Ca2+ and K+ are involved in neurotransmission. It appears that taurine stored in glial cells, has an important effect on ion homeostasis in the CNS and may act indirectly on neuronal excitability. 相似文献
95.
R D Allen J M Grierson H Ekberg W J Hawthorne P Williamson S A Deane J R Chapman G J Stewart J M Little 《The American journal of pathology》1991,138(2):303-312
In preparation for assessment of percutaneous biopsies in our clinical pancreas transplant program, a working knowledge of the histopathologic changes after transplantation was obtained in a longitudinal open biopsy study of 16 dogs receiving bladder-drained whole pancreas allografts. Edema, extravasation of polymorphs, and lymphocytes associated with focal parenchymal injury were early, invariable, and probably nonspecific findings. The initial feature of unmodified rejection was the appearance of capillary and small vein endothelial changes with mainly perivascular inflammatory cell infiltration. Acinar cell loss occurred early and was progressive, whereas islets and ducts were relatively preserved, indicating that acinar tissue may be more vulnerable to lytic necrosis when damaged. Functional rejection, determined by fasting urinary amylase levels, was at a stage of extensive and irreversible necrosis. Functioning grafts in immunosuppressed dogs had minor and transient endothelial changes with absence of class II antigen staining of parenchymal cells. 相似文献
96.
James W. Allen Charles F. Shuler Samuel A. Latt 《Somatic Cell and Molecular Genetics》1978,4(4):393-405
5-Bromodeoxyuridine (BrdU) tablets with different physical characteristics are useful in a wide variety of studies requiring detection of DNA replication in vivo. These tablets can effect a high substitution of BrdU in DNA, thereby permitting sister chromatid differentiation in chromosomes stained with 33258 Hoechst alone or in conjunction with Giemsa. Baseline and cyclophosphamide-induced in vivo sister chromatid exchange frequencies in mouse spleen, marrow, and thymus were measured and found to be significantly greater than those in spermatogonia. Sister chromatid exchange analysis was also extended to mouse liver and to Chinese hamster and Armenian hamster marrow cells. Sister chromatid differentiation was observed in Armenian hamster meiotic tissue, and evidence for interhomolog chromatid exchange obtained. 相似文献
97.
Extending the linear-quadratic model for large fraction doses pertinent to stereotactic radiotherapy 总被引:1,自引:0,他引:1
Ongoing clinical trials designed to explore the use of extracranial stereotactic radiosurgery (ESR) for different tumour sites use large doses per fraction (15, 20, 30 Gy or even larger). The question of whether the linear-quadratic (LQ) model is appropriate to describe radiation response for such large fraction doses has been raised and has not been answered definitively. It has been proposed that mechanism-based models, such as the lethal-potentially lethal (LPL) model, could be more appropriate for such large fraction/acute doses. However, such models are not well characterized with clinical data and they are generally not easy to use. The purpose of this work is to modify the LQ model to more accurately describe radiation response for high fraction/acute doses. A new parameter is introduced in the modified LQ (MLQ) model. The new parameter introduced is characterized based both on in vitro cell survival data of several human tumour cell lines and in vivo animal iso-effect curves. The MLQ model produces a better fit to the iso-effect data than the LQ model. For a high single dose irradiation, the prediction of the MLQ is consistent with that from the LPL model. Unlike the LPL model, the MLQ model retains the simplicity of the LQ model and uses the well-characterized alpha and beta parameters. This work indicates that the standard LQ model can lead to erroneous results when used to calculate iso-effects with large fraction doses, such as those used for ESR. We present a solution to this problem. 相似文献
98.
In a forearm position-matching task in the horizontal plane, when one (reference) arm is conditioned by contraction and length changes, subjects make systematic errors in the placement of their other, indicator arm. Here we describe experiments that demonstrate the importance not just of conditioning the reference arm, but of the indicator arm as well. Total errors from muscle conditioning represented up to a quarter of the angular range available to subjects. The sizes of the observed effects have led us to repeat other, previously reported experiments. In a matching task in the vertical plane, when muscles of both arms were conditioned identically, if the subject supported their arms themselves, or when the arms were loaded by the addition of weights, the loading did not introduce new position errors. To test the effect of exercise, subjects' elbow flexors were exercised eccentrically or concentrically by asking them to lower or raise a set of weights using forearm muscles. The exercise produced 25–30% decreases in maximum voluntary contraction strength of elbow flexors and this led to significant position-matching errors. The directions and magnitudes of the errors were similar after the two forms of exercise and indicated that subjects perceived their exercised muscles to be longer than they actually were. To conclude, the new data from loading the arm are not consistent with the idea that the sense of effort accompanying support of a load, provides positional information in any simple way. Our current working hypothesis is that when muscles are active, position-sense involves operation of a forward internal model. Loading the arm produces predictable changes in motor output and afferent feedback whereas changes after exercise are unpredictable. This difference leads to exercise-dependent errors. 相似文献
99.
Thomson KL Gloyn AL Colclough K Batten M Allen LI Beards F Hattersley AT Ellard S 《Human mutation》2003,22(5):417
Maturity-onset diabetes of the young (MODY) resulting from mutations in the glucokinase (GCK) gene accounts for approximately 20% of MODY in the UK. We have performed fluorescent single stranded conformation polymorphism (F-SSCP) analysis or direct sequencing of the GCK gene in 212 patients referred as part of a research cohort or for diagnostic molecular genetic testing. Mutation screening has identified 43 different mutations in 61 individuals, of which 21 are novel. This report details the mutations identified and their associated clinical features. 相似文献
100.
Synaptic actions of peripheral nerve impulses upon Deiters neurones via the mossy fibre afferents 下载免费PDF全文
1. The cerebellar integration of sensory inputs to Deiters neurones was investigated in decerebrate cats. In some preparations decerebration was combined with transection of the olivocerebellar fibres.2. In the latter preparations peripheral nerve impulses generally produced a response consisting of a sequence of the following post-synaptic potentials: (i) an initial e.p.s.p. (d(1)), (ii) early i.p.s.p. (h(1)), (iii) later i.p.s.p. (h(2)).3. The mean latencies of d(1), h(1) and h(2) were 5.7, 7.3 and 9.8 msec from the forelimb nerves, and 7.5, 9.0 and 13.4 msec from the hind limb nerves, respectively.4. The stimulus intensity-response relation indicates that the Group I muscle afferents as well as the low threshold cutaneous afferents contribute to the response.5. In the preparations with the intact inferior olive there were additional components of the post-synaptic potentials: a later e.p.s.p. (d(2)) and another later i.p.s.p. (h(3)), their mean latencies being 15.3 and 19.7 msec from the forelimb nerves, and 18.0 and 21.3 msec from the hind limb nerves, respectively.6. The d(1) and h(2) components were attributed to the mossy fibre afferents and d(2) and h(3) to the climbing fibres; d(1) and d(2) were due to excitation through the collaterals of the mossy and climbing fibres, and h(2) and h(3) to inhibition from Purkyne cells activated by the mossy and climbing fibres, respectively. h(1) was too early to be produced through the cerebellum, and was probably mediated by inhibitory neurones in the reticular formation. 相似文献