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排序方式: 共有1172条查询结果,搜索用时 15 毫秒
1.
Kari Aalto Teddy Holmstr m Erkki Karaharju Jaakko Joukainen Pekka Paavolainen Par Sl tis 《Acta orthopaedica》1987,58(1):66-70
Bone repair was studied in the rabbit tibiofibular bone after a midshaft transverse osteotomy stabilized by external fixation and heavy compression. Both subendosteal and subperiosteal callus formation with concomitant contact healing were observed within 3 weeks, and were further succeeded by subendosteal resorption and increased porosis resulting in atrophy of the cortical bone. Subjected to the torsion test, the bones exhibited restoration of strength within 3 weeks, with maximal energy absorption and elasticity at 6 weeks. The failure of the osteotomy in the torsion test, with radiographic visibility of the osteotomy, characterized the soft-tissue type of behavior of the bones. Hard-tissue like behaviour of the bones with resistance to torsion at the osteotomy site and radiographic obliteration of the osteotomy line occurred by 12 weeks, indicating complete union of the osteotomy. Our experiments demonstrate that elastic external fixation is preferable to the rigid compression plate. 相似文献
2.
Tommi Sukuvaara Erkki M. J. Koski Aki Mäkivirta Aarno Kari 《Journal of clinical monitoring and computing》1994,10(2):117-126
A knowledge-based alarm system for intensive care monitoring was designed, built, tested on-line, and evaluated. The system is a functional prototype of a highly specific patient monitor providing alarms on hypovolemia, hyperdynamic state, left ventricular failure and hypoventilation. These intelligent alarm functions aim to maintain the quality of patient monitoring even if nurses' attention is temporarily reduced or focused elsewhere. The alarm system has an electronic access to data available in a multichannel patient monitor and the patient data management system of the intensive care unit. Median filtering, trend estimation, and rule-based reasoning are applied when processing the measured variables and estimating the patient's state. 相似文献
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Authors studied the numbers of T-cell receptor-alpha/beta, gamma/delta positive lymphocytes and the proportion of gamma/delta positive cells with a non-disulfide linked form of gamma/delta receptor in jejunal mucosa from 19 coeliatic children, in rectal specimens from 14 children with ulcerative colitis, as well as in specimens of 23 healthy controls. Monoclonal antibodies and a sensitive indirect peroxidase method were used. In the lamina propria and epithelium of a normal jejunum and rectum, as well as in the rectal and colonic mucosae of patients with ulcerative colitis only low numbers of gamma/delta positive cells were seen. In the lamina propria, in the surface epithelium, as well as, in the epithelium of the Lieberkühn crypts the number of gamma/delta positive cells were significantly higher than in the controls before treatment, during gluten free diet and after the gluten challenge. In the epithelium the absolute numbers of these cells remained constant during gluten elimination and provocation. The constantly elevated population of gamma/delta positive T-cells in coeliac disease might show their primary pathogenetic role in this disorder. The detection of elevated number of intraepithelial gamma/delta T-cells may have significance in the diagnosis of coeliac disease. 相似文献
5.
Petru Liuba Jerker Persson Jukka Luoma Seppo Yl?-Herttuala Erkki Pesonen 《European heart journal》2003,24(6):515-521
BACKGROUND: Atherosclerosis begins early in life. Infections might contribute to the pathogenesis of atherosclerosis. In this study, we investigated whether acute infections in children could alter the carotid wall morphology and the lipid profile. METHODS: Mean carotid intima-media thickness (IMT) was measured by high-resolution ultrasound in 28 hospitalised children (mean age: 5+/-2 years), who fulfilled the diagnostic criteria of acute infections (body temperature, >38 degrees C; C-reactive protein, >15mg/ml, and clinical), and in 20 age- and gender-matched controls. Antibodies against oxidised low-density lipoprotein (anti-oxLDL antibodies), as well as total and high-density lipoprotein cholesterol (HDL-C) were analysed in all children. The infection group was investigated both during the acute illness and 3 months after clinical recovery (post-infection). RESULTS: During the acute illness, the infection group had elevated anti-oxLDL antibodies and decreased HDL-C, as compared to those obtained at 3 months and in controls (p<0.05). These changes in the infection group were followed, at 3 months, by thickening of carotid intima-media. Those who received antibiotics during their acute illness had less carotid thickening than those who were not treated with antibiotics (p<0.05). CONCLUSION: Acute infections in children seem to be accompanied by enhanced oxidative modification of LDL and by decrease in HDL-C. These lipid changes may be followed by thickening of carotid artery intima-media. These findings suggest that, in childhood, acute infections could be associated with increased risk of atherosclerosis, and warrant further studies on this topic. 相似文献
6.
Erkki Lotspeich Markus Schoene Heinz Gerngroß Roland Schmidt Reinhard Steinmann Marco Ramadani Susanne Gansauge 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(5):559-566
Introduction Postoperative treatment for colorectal cancer depends on tumor stage as defined by the International Union Against Cancer
(UICC). Adjuvant chemotherapy is not recommended in patients without lymph node involvement (UICC stages I and II). As many
as 20–30% of these patients, however, will develop recurrence.
Aims and objectives We conducted this study to determine the presence of disseminated tumor cells in the lymph nodes by quantitative real-time
polymerase chain reaction (QRT-PCR) for cytokeratin 20 (CK20) in an attempt to provide supplementary information compared
to histopathological findings.
Materials and methods Using a standard QRT-PCR assay, we examined primary tumors and 391 lymph nodes from 31 patients with completely resected colorectal
cancer.
Results Of the 31 primary tumors, 29 were positive for CK20 by QRT-PCR.
Discussion An examination of the lymph nodes from the 29 patients with CK20-positive primary tumors revealed that 35 (92.1% sensitivity)
of the 38 histopathologically positive lymph nodes and 54 (16.7%) of the 324 histopathologically negative lymph nodes were
positive by molecular analysis. CK20 expression was detected in 10 (100%) of 10 patients with a histopathologically positive
lymph node status (pN1). In 9 (47.4%) of 19 patients with negative histopathological results (pN0), we detected a CK20 mRNA
signal in at least one lymph node. Whereas eight patients with histopathologically negative lymph nodes could be upstaged
on the basis of the molecular findings, no patient would be downstaged.
Conclusion Our results suggest that QRT-PCR for CK20 is a useful tool for the quantitative detection of micrometastases in the regional
lymph nodes. We introduce a standardized procedure that integrates a molecular diagnostic technique in the clinical staging. 相似文献
7.
The relationship between job-related burnout and depressive disorders--results from the Finnish Health 2000 Study 总被引:7,自引:0,他引:7
Ahola K Honkonen T Isometsä E Kalimo R Nykyri E Aromaa A Lönnqvist J 《Journal of affective disorders》2005,88(1):55-62
BACKGROUND: Depression and burnout are common health problems in working populations today. They appear to be interrelated, and the need for their differential diagnosis has been highlighted in many reviews. We analysed the overlap of job-related burnout and depressive disorders, i.e., major depressive disorder, dysthymia, and minor depressive disorder. METHODS: We used the population-based 'Health 2000 Study' in Finland. Our nationally representative sample comprised 3276 employees aged 30-64 years. Burnout was assessed with the Maslach Burnout Inventory-General Survey. Diagnoses of depressive disorders were based on the Composite International Diagnostic Interview. RESULTS: Burnout and depressive disorders were clearly related. The risk of depressive disorders, especially major depressive disorder (12-month prevalence), was greater when burnout was severe. Half of the participants with severe burnout had some depressive disorder. Those with a current major depressive episode suffered from serious burnout more often than those who had suffered a major depressive episode earlier. LIMITATIONS: This study was cross-sectional. CONCLUSIONS: The concepts of burnout and depression complement each other and cover partly overlapping phenomena. Depressive disorders are related to job-related burnout, particularly when it is severe. A current major depressive episode is likely to be associated with the experience of burnout. When encountering working patients, it is recommended to assess both the occurrence of burnout and of depressive disorders. 相似文献
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9.
Kantele A Savilahti E Tiimonen H Iikkanen K Autio S Kantele JM 《European journal of immunology》2003,33(12):3275-3283
In contrast to T cells, information on skin-homing B cells expressing the cutaneous lymphocyte antigen (CLA) is sparse. CLA expression on human B cells was investigated among circulating immunoglobulin-secreting cells (ISC) and among antigen-specific antibody-secreting cells (ASC) elicited by parenteral, oral or rectal primary immunization, or by parenteral or oral secondary immunization with Salmonella typhi Ty21a. CLA expression was examined by combining cell sorting with an enzyme-linked immunospot assay. Among all ISC, the proportion of CLA(+) cells was 13-21%. Parenteral immunization induced antigen-specific ASC of which 13% were CLA(+), while oral and rectal immunizations were followed by only 1% of CLA(+) ASC (p<0.001). Oral re-immunization was followed by an up-regulation of CLA (34-48%) regardless of the route of priming. Parenteral re-immunization elicited ASC of which 9-14% were CLA(+). In conclusion, the expression of CLA on human effector B cells depends on the site of antigen encounter: intestinal stimulation elicits cells with no CLA, while parenteral encounter elicits significant numbers of CLA(+) cells. Even though primary antigen encounter in the intestine failed to stimulate CLA expression, up-regulation of CLA was found upon intestinal antigen re-encounter. These findings may be of relevance in the pathogenesis of some cutaneous disorders. 相似文献
10.
Westerholm-Ormio M Garioch J Ketola I Savilahti E 《Clinical and experimental immunology》2002,128(1):94-101
T helper cell type 1 (Th1) response to gluten has been implicated in the pathogenesis of coeliac disease (CD). To characterize immunological activation and mild inflammations leading to overt CD in potential coeliac patients, jejunal biopsies were obtained from family members of patients with CD or dermatitis herpetiformis (DH). Nine family members and one latent CD, eight CD patients and eight normal controls furnished jejunal biopsy specimens. Immunohistochemical staining of sections for interleukin-1alpha (IL-1alpha), IL-2, IL-4, interferon-gamma (IFN-gamma), tumour necrosis factor alpha (TNF-alpha), CD3, gammadelta-T cell receptor (gammadelta-TCR), and alphabeta-TCR was carried out with monoclonal antibodies. Further, expression of IL-4 and IFN-gamma messenger RNA was detected by radioactive in situ hybridization in these same samples. In lamina propria, CD patients and potential CD patients had higher densities of IL-2 (P = 0.028, P = 0.043), IL-4 (P = 0.021, P = 0.034) and IFN-gamma positive cells (P = 0.000, P = 0.009) than did controls. Moreover, CD patients showed a higher density of TNF-alpha positive cells (P = 0.012, P = 0.001) than the other two groups, and expression of IFN-gamma mRNA (P = 0.035) was higher in them than in the other two study groups. Additionally, higher densities of TNF-alpha and IFN-gamma positive cells occurred in potential CD patients with high gammadelta-TCR+ intraepithelial lymphocytes (IELs). Our findings support the hypothesis that lamina propria T cells and macrophages, through their secretion of cytokines, play a central role in the pathogenesis of coeliac disease. The inflammatory cytokines found in potential CD specimens strongly suggest that these inflammatory markers can be identified long before visible villous changes have occurred. 相似文献