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91.
初中生主观幸福感与人格特征的关系研究   总被引:19,自引:2,他引:19  
目的:探讨初中生主观幸福感与人格特征之间的关系。方法:采用中学生主观幸福感量表和EPQ对283名中学生进行调查。结果:(1)初中生的主观幸福感水平在中等程度以上,体验到的正性情感较多,但是仍有一定比例的学生体验到较强的不幸福感。男女生在总体幸福感、家庭满意感、自我满意感、同伴交往满意感和生活条件满意感上存在显著的差异,女生得分均高于男生。(2)总体幸福感及各因子与精神质和神经质显著负相关,与内外向显著正相关。结论:初中生主观幸福感与人格特征关系密切。  相似文献   
92.
The permanent human cell line C3842 was established from a secondary chondrosarcoma in a typical case of Olliers disease. In the present study, we analyzed the morphological, cytogenetic and molecular biological characteristics of the cultured cells in comparison with the original tumor and investigated the invasion properties of the tumor model using functional imaging of proteolysis, matrigel assay and chick chorioallantoic membrane assay. C3842 cells exhibit the typical features of malignant cartilage tumor cells in vitro, including the expression of collagen types II, IX, XI and aggrecan. The proteolytic ability of C3842 cells is attributed to the expression of several proteases, such as cathepsin B, urokinase plasminogen activator and matrix-metalloproteinase-2, which enable the cells to degrade collagen type I and to permeate matrigel matrix. In accordance with the biological features in vivo, C3842 cells are not able to invade through the epithelium of the chick chorioallantoic membrane. In conclusion, the cell line C3842 provides the first model of a secondary chondrosarcoma in Olliers disease in vitro, which is characterized by distinct features of such malignant cartilage tumors.  相似文献   
93.
Summary For years, brown tumors have been considered to be a characteristic of primary hyperparathyroidism. However, since 1963 several reports indicate the incidence of brown tumors in patients with renal secondary hyperparathyroidism to be 1.5%–1.7%. The appearance of multiple brown tumor lesions is rather uncommon in secondary hyperparathyroidism which is also true for malabsorption as its cause. We report on a 56-year-old man presenting with pain in the bones and multiple osteolyses. A bone biopsy specimen and the laboratory examinations were indicative of secondary hyperparathyroidism caused by malabsorption most likely due to Billroth's II/I gastric resection. Thus, the patient's osteolyses represent brown tumors which have been induced by nutritional secondary hyperparathyroidism.  相似文献   
94.
We describe patient E.P. who occasionally perceives a ‘ghost' hand which copies the previous positions of the left hand with a 0.5–1 min time lag, but follows the movement patterns of the right hand. The symptoms started after an operation of a ruptured aneurysm, followed by an infarction of the right frontal lobe; E.P. also has a previously lesioned corpus callosum. Neuromagnetic recordings revealed that activity of the left secondary somatosensory cortex was strongly suppressed during the ghost arm percept, thereby providing an objective correlate for E.P.'s sensations. We conclude that simultaneous mental contents about body scheme may be based on neural information extracted at considerably different times, resulting in fragmentation of bodily awareness.  相似文献   
95.
A cricial part of secondary palate morphogenesis is the movement of the palatal shelves from an initial vertical position on either side of the tongue to a final horizontal one above it to achieve palate closure. The immunocytochemical localization of extracellular matrix (ECM) molecules in the palatal shelf during this remodelling and reorientation revealed the existence of an ECM infrastructure within the mesenchyme. The major components of this infrastructure were collagen III, fibronectin, and hyaluronate (HA). With remodelling, HA's domain within the mesenchyme was expanded, whereas those of fibronectin and collagen III became more circumscribed. The expansion of an HA-rich matrix within the mesenchyme is thought to be crucial for palatal reorientation. The results of this study suggest that, as this expansion occurs, it is modulated by collagen and fibronectin components of the ECM infrastructure. Prior to shelf remodelling, this infrastructure may be anchored by a specialized region of the midoral epithelial-mesenchymal interface and the subjacent mesenchyme which is characterized by the unique distribution of collagen III, fibronectin, and tenascin. The midoral palatal epithelium also may play a role in directing shelf expansion. This epithelial region undergoes changes in cell packing and epithelial cell layering that correlate with shelf remodelling. These changes occur concomitantly with changes in the expression of collagen III, collagen IV, and laminin within the underlying basement membrane. The localization and patterning of tenascin within the developing palate suggests that it not only contributes to the postulated anchoring structure of the midoral epithelial-mesenchymal region, but also plays a role in the determining the fate of the medial edge epithelial cells during the final stage of palate closure.© Willey-Liss, Inc.  相似文献   
96.
Summary A hypothesis is forwarded regarding the role of secondary spindle afferents and the FRA (flexor reflex afferents) in motor control. The hypothesis is based on evidence (cf. Lundberg et al. 1987a, b) summarized in 9 introductory paragraphs. Group II excitation. It is postulated that subsets of excitatory group II interneurones (transmitting disynaptic group II excitation to motoneurones) may be used by the brain to mediate motor commands. It is assumed that the brain selects subsets of interneurones with convergence of secondary afferents from muscles whose activity is required for the movement. During movements depending on coactivation of static -motoneurones impulses in secondary afferents may servo-control transmission to -motoneurones at an interneuronal level. The large group II unitary EPSPs in interneurones are taken to indicate that, given an adequate interneuronal excitability, impulses in single secondary afferents may fire the interneurone and produce EPSPs in motoneurones; interneuronal transmission would then be equivalent to that in a monosynaptic pathway but with impulses from different muscles combining into one line. It is postulated that impulses in the FRA are evoked by the active movements and that the role of the multisensory convergence from the FRA onto the group II interneurones is to provide the high background excitability which allows the secondary spindle afferents to operate as outlined above. The working hypothesis is put forward that a movement governed by the excitatory group II interneurones is initiated by descending activation of these interneurones, but is maintained in a later phase by the combined effect of FRA activity evoked by the movement and by spindle secondaries activated by descending activation of static -motoneurones. As in the original follow up length servo hypothesis (Rossi 1927; Merton 1953), we assume that a movement at least in a certain phase can be governed from the brain solely or mainly via static -motoneurones. However, our hypothesis implies that the excitatory group II reflex connexions have a strength which does not allow transmission to motoneurones at rest and that the increase in the gain of transmission during an active movement is supplied by the movement itself. Group II inhibition. It is suggested that the inhibitory reflex pathways like the excitatory ones have subsets of interneurones with limited group II convergence. When higher centres utilize a subset of excitatory group II interneurones to evoke a given movement, they may mobilize inhibitory subsets to inhibit muscles not required in the movement. Inhibition may be reciprocal of extensors during flexor activation (the spinal pattern), of flexors during extensor activation or of flexors and extensors in more complex movements involving cocontraction of other flexors and extensors. It is postulated that group II inhibition depends on conjoint activation from spindle afferents and other sources (descending and/or the FRA) so that inhibition may be coupled to group II excitation of other motoneurones. Such a coupling would correspond to the --linkage in reciprocal Ia inhibition (Lundberg 1970) and is denoted --linkage in lateral group II inhibition. FRA and other reflex pathways. Results are summarized showing that the FRA evoke convergent excitation in interneurones not only in group II reflex pathways but also in other reflex pathways like the reciprocal Ia inhibitory, the nonreciprocal group I inhibitory and probably also in specialized reflex pathways from cutaneous afferents. It is inferred that facilitation of reflex transmission by impulses in the FRA evoked by the active movement may be a general principle. In this way reflex transmission to -motoneurones may be weak at rest and not disturb passive movements but have a high gain when the reflexes are required to regulate active movement.This work was supported by the Swedish Medical Research Council (project no. 94)  相似文献   
97.
Osteopenia and osteoporosis are well-known complications detected in celiac disease patients with still obscure pathogenesis. In the present study we investigated the presence of circulating anti-bone autoantibodies in patients with celiac disease and explored their role in the associated bone disease. We evaluated serum samples from 33 patients at the time of diagnosis and from 20 of them after treatment. Sera from patients with inflammatory bowel disease (n = 9), nonceliac osteoporotic (n = 18), and healthy individuals (n = 10) were used as controls. The presence of IgA specific anti-bone antibodies was first investigated using indirect immunofluorescence on cryosections of fetal rat tibia (20-day pregnancy). Furthermore, samples were homogenized and total tissue extracts were subjected to Western blot analysis to confirm immunoreactivity. At diagnosis, sera from 51.5% (17/33) of celiac patients had antibodies that recognized antigenic structures in chondrocytes and the extracellular matrix along mature cartilage, bone interface, and perichondrium of fetal rat bone. Among controls, only two osteoporotic patients showed very low titles of anti-bone autoantibodies. The immunostaining was localized in areas where an active mineralization process occurred and was similar to the distribution of the native bone tissue transglutaminase. The frequency of patients with positive baseline titers of anti-bone antibodies diminished significantly after treatment (P = 0.048). Western blot assays confirmed the presence of autoantibodies in sera from patients with a positive immunofluorescence staining. Autoantibodies recognized a major protein band on tissue extracts with a molecular weight of 77–80 kDa, which could be displaced when sera were preadsorbed with human recombinant tissue transglutaminase. We provide original evidence that patients with celiac disease have IgA-type circulating autoantibodies against intra- and extracellular structures of fetal rat tibia. Our findings suggest that these antibodies recognize bone tissue transglutaminase as the autoantigen, and based on the localization of the immunoreactivity we speculate that they might have an active role in the pathophysiology of celiac disease-associated bone complications.  相似文献   
98.
PurposeTo investigate the effect of nutritional factors on bone mineral density (BMD) using quantitative computed tomography combined with blood biochemistry in patients on maintenance hemodialysis (MHD).MethodsSixty patients on MHD were divided into osteopenia (n = 20) and nonosteopenia (n = 40) groups. BMD, fat, and muscle mass were measured by quantitative computed tomography. The calcification of coronary artery and hilar lymph node and computed tomography attenuation values of the liver and spleen were also analyzed. Differences between the two groups were compared, and the risk factors for osteopenia were analyzed by logistic regression analysis.ResultsPatients in the osteopenia group had lower albumin levels than those in the nonosteopenia group (37.84 ± 3.00 vs 42.03 ± 4.05 g/L; P < .001). Logistic regression showed that patients with lower albumin levels had a higher risk of osteopenia (odds ratio, 1.462; 95% confidence interval, 1.313–1.801; P = .003). BMD was negatively correlated with fat mass (r = ?0.365, P = .004) and positively correlated with the ratio of muscle mass to fat mass (r = 0.431, P = .001). There was no significant difference in the rate of calcification of coronary artery or hilar lymph nodes between the two groups. Computed tomography values of the liver and spleen were positively correlated with the duration of dialysis (r = 0.55, P = .001; r = 0.42, P < .001, respectively).ConclusionLow albumin levels are associated with an increased risk of osteopenia in patients on MHD. Abdominal fat is a risk factor for reduction in BMD in MHD patients, and the ratio of abdominal muscle mass to fat mass is a protective factor for BMD.  相似文献   
99.
Osteopenia/osteoporosis and sarcopenia are common geriatric diseases among older adults and harm activities of daily living (ADL) and quality of life (QOL). Osteosarcopenia is a unique syndrome that is a concomitant of both osteopenia/osteoporosis and sarcopenia. This review aimed to summarize the related factors and clinical outcomes of osteosarcopenia to facilitate understanding, evaluation, prevention, treatment, and further research on osteosarcopenia. We searched the literature to include meta-analyses, reviews, and clinical trials. The prevalence of osteosarcopenia among community-dwelling older adults is significantly higher in female (up to 64.3%) compared to male (8–11%). Osteosarcopenia is a risk factor for death, fractures, and falls based on longitudinal studies. However, the associations between osteosarcopenia and many other factors have been derived based on cross-sectional studies, so the causal relationship is not clear. Few studies of osteosarcopenia in hospitals have been conducted. Osteosarcopenia is a new concept and has not yet been fully researched its relationship to clinical outcomes. Longitudinal studies and high-quality interventional studies are warranted in the future.  相似文献   
100.
Osteoporosis affects women twice as often as men. Additionally, it is estimated that 0.3 million and 1.7 million people have hip fractures in the USA and Europe, respectively. Having a proper peak bone mass and keeping it as long as possible is especially important for osteoporosis prevention. One of the most important calcium sources is milk and dairy products. Breast milk is the best infant food, but milk should not be avoided later in life to prevent losing bone mass. On the other hand, more and more people limit their milk consumption and consume other dairy or non-dairy products. For example, they are usually replaced with plant beverages, which should be consumed carefully in several age groups. Additionally, an important element of milk and dairy products, as well as plant beverages, are probiotics and prebiotics, which may modulate bone turnover. Dietary recommendations focused on milk, and dairy products are an important element for the prevention of osteoporosis.  相似文献   
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