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31.
The submerged platform or Morris water escape task is widely used to study genetic variation in spatial learning and memory, but interpretation is sometimes difficult because of wall hugging, jumping off the platform, floating or non-spatial swim strategies. We modified the task by introducing four wide arms into the circular tank and adding features that reduced, eliminated, or compensated for several competing behaviors. Three versions of the 4-arm task were evaluated in detail, and the third version yielded good results for six of eight inbred strains. Furthermore, the 4-arm task could be scored adequately without computerized video tracking. Although performance on the 4-arm task was generally superior to the Morris maze, the extent of the improvement was strain dependent. Two strains with retinal degeneration (C3H/HeJ, FVB/NJ) performed poorly on both the Morris and 4-arm mazes, whereas C57BL/6J and DBA/2J did well on both mazes. A/J performed poorly on the Morris task but became very proficient on the 4-arm maze, despite its strong tendency to hug the walls of the tank. The BALB/cByJ strain, on the other hand, exhibited the best probe trial performance on the Morris maze but was very slow in acquiring the 4-arm task. We conclude that no single task can reveal the full richness of spatially guided behavior in a wide range of mouse genotypes.  相似文献   
32.
The present study was undertaken to further approach the importance of 14q deletions in renal cell carcinoma (RCC) development. The initial screening using 2 RFLP markers from distal 14q identified loss of heterozygosity (LOH) in 17 of 45 informative cases (38%). In addition, in 37 patients with primary RCCs, it was shown that cases with LOH at D14S1 had significantly shorter survival as compared to cases with-out LOH (p<0.005). Subsequently, 19 primary tumors and 6 metastases were genotyped for 20 polymorphic markers and the findings were evaluated in relation to the clinical characteristics of the primary tumor and the survival during follow-up. Overall LOH was identified in 11 of the primary tumors (58%) and 4 of the metastases (66%). In metastases as well as in primary tumors the highest frequency of LOH was detected with markers from the distal part of the chromosome i.e., 14q32. Five minimal regions of overlapping deletions were identified, three of which (II, IV and V) were defined from the primary RCCs. From centromere to telomere these include region I proximal of D14S259, region II between D14S255 and D14S588, region III in the D14S61-D14S617 interval, region IV between D14S617 and D14S260, and region V telomeric of D14S1007. For the primary tumors, losses in regions IV and V were each significantly associated with high tumor grade (i.e., grade 3; p<0.05). Furthermore, LOH within region IV was also associated with a significantly shorter survival (p=0.02). In conclusion, the high frequency of distal 14q LOH supports the relevance of this alteration for the development of RCC.  相似文献   
33.
BACKGROUND: In patients with acute severe respiratory failure (ARF) treated with extracorporeal membrane oxygenation (ECMO) the radiological evaluation has until now almost exclusively relied on bedside radiography and US. At St. G?ran/Karolinska ECMO centre CT has become a routine complement to bedside examinations. OBJECTIVE: To review retrospectively the frequency, indications and findings on CT of patients with ARF on ECMO and to evaluate the risk of complications associated with transportation for CT examinations. MATERIALS AND METHODS: One hundred twelve neonates, children and adults were treated with ECMO from May 1994 to January 2001. Forty-six per cent of these patients had CT examinations on one or more occasions during ECMO, giving a total number of 238 examination sites on 104 occasions. All CT examinations were performed in the Paediatric Radiology Department and included a 10-min transport using a mobile ECMO system. RESULTS: CT was more often performed in older patients and in patients with long ECMO runs. The main indications were suspected complications of ECMO and/or the underlying disease or a delay in clinical improvement. In 57% of the CT occasions, significant findings affecting treatment were revealed. There were no complications associated with the examinations or transport. CONCLUSIONS: CT is safe and useful in evaluation of patients with ARF during ECMO.  相似文献   
34.
High concentrations of Hg, Cd, Pb, Cu, and Zn were found in the euxinic sediment of the inner archipelago of Stockholm. In the sulfide-rich sediment, they are precipitated as metal sulfides with low dissolving capacity and bioavailability. In two experiments, the significance of acid-volatile sulfide (AVS) and dissolved sulfides for mobility, bioavailability, and toxicity of metals were studied by oxygenation of intact sediment cores. Influence of bioturbating deposit-feeding amphipods, that is, Monoporeia affinis, was examined on studied sediment processes. Results showed a low mobility of most metals except Cd and Zn. Bioturbation did not enhance mobility. Cd and Zn, released from the sediment, were not bioaccumulated in amphipods. In contrast, the less mobile metals Hg and Pb were bioaccumulated. A low toxicity of contaminated sediments, in terms of mortality and embryonic malformations of amphipods, was recorded. Results indicate that Cd, Zn, and Cu are comparatively unavailable after oxygenation of the metal sulfides. Similar results were recorded in contaminated sediments differing in redox potential, AVS, dissolved sulfides, and organic contents, suggesting that other metal ligands, in addition to AVS, are important for metal bioavailability and toxicity in anoxic and suboxic environments.  相似文献   
35.
This study aims to evaluate incidence, patterns and epidemiology of mandibular condylar fractures (MCF) to propose a treatment strategy for managing MCF and analyze the factors which influence the outcome. One hundred and seventy-five MCF’s were evaluated over a four year period and their pattern was recorded in terms of displacement, level of fracture, age of incidence and dental occlusion. Of the 2,718 facial bone fractures, MCF incidence was the third most common at 18.39 %. Of 175 MCF 58.8 % were unilateral and 41.12 % were bilateral. 67 % of bilateral fractures and 43.8 % of unilateral fractures were associated with midline symphysis and contralateral parasymphysis fractures respectively. Most of the MCF was seen in the age group of above 16 years and 50 % of them were at subcondylar level (below the neck of the condyle). Majority of MCF sustained due to inter personal violence were undisplaced (72.7 %) and contrary to this majority of MCF sustained during road traffic accident were displaced. 62.9 % of total fractures required open reduction and rigid fixation and 37.1 % were managed with closed reduction. 80 % of MCF managed with closed reduction were in the age group of below 16 years. From this study it can be concluded that the treatment algorithm proposed for managing MCF is reliable and easy to adopt. We observed that absolute indication for open reduction of MCF is inability to achieve satisfactory occlusion by closed method and absolute contraindication for open reduction is condylar head fracture irrespective of the age of the patient.  相似文献   
36.
BACKGROUND: The two widely spread human polyomaviruses, BK virus (BKV) and JC virus (JCV) establish latency in the urinary tract, and can be reactivated in AIDS. JCV might cause progressive multifocal leucoencephalopathy, but although up to 60% of AIDS patients excrete BKV in the urine there have been few reports of BKV-related renal and/or neurological disease in AIDS. OBJECTIVE: To report on an AIDS patient with progressive renal and neurological symptoms involving the retina. DESIGN: Case report. SETTING: Venh?lsan, S?der Hospital, Stockholm, Sweden. METHODS: The brain, eye tissue, cerebrospinal fluid, urine and peripheral blood mononuclear cells were analysed by nested PCR for polyoma-virus DNA. Macroscopical and microscopical examination were performed of the kidney and brain post mortem. Immunohistochemical stainings for the two BKV proteins, the VP1 and the agnoprotein, were performed on autopsy material and virus infected tissue culture cells. RESULTS: BKV could be demonstrated in the brain, cerebrospinal fluid, eye tissues, kidneys and peripheral blood mononuclear cells. CONCLUSION: During 6 years, approximately 400 cerebrospinal fluid samples from immunosuppressed individuals with neurological symptoms have been investigated by PCR for the presence of polyomaviruses. BKV DNA has, so far, only been found in the case reported here. Although reports of BKV infections in the nervous system are rare, there is now evidence for its occurrence in immunocompromised patients and the diagnosis should be considered in such patients with neurological symptoms and signs of renal disease. The diagnosis is simple to verify and is important to establish.  相似文献   
37.
38.
Patterns of cerebellar foliation in recombinant inbred mice   总被引:2,自引:0,他引:2  
Morphometric analysis of cerebellar foliation patterns at the midsagittal plane was done in the inbred strains BALB/cByJ, C57BL/6ByJ and their 7 recombinant inbred strains in order to assess possible major gene influences. The cerebellum was dissected away from the brainstem and weighed prior to histology so that measures of the depth of fissures and sulci could be related to overall size of the brain and cerebellum. Results for 177 mice revealed that many brains had extra sulci present within the central lobe, the culmen, the declive and the uvula, and that patterns within a genetically uniform inbred strain were highly variable. The measure of sulcus depth was continuous, showing no evidence of a normal versus abnormal dichotomy. Furthermore, the frequency and depth of extra sulci were greater in mice with larger cerebella. Strain differences in size of the whole brain and cerebellum clearly resulted from several genetic loci. This was also true of the extra sulci, except for the declival sulcus which revealed a single gene influence. The gene symbol 'declival sulcus of cerebellum' (dsc) is proposed.  相似文献   
39.
The objective of the study was to examine the efficacy of EMDR treatment for children with post-traumatic stress disorder (PTSD) compared with untreated children in a waiting list control group (WLC) participating in a randomized controlled superiority trial (RCT). Thirty-three 6-16-year-old children with a DSM-IV diagnosis of PTSD were randomly assigned to eight weekly EMDR sessions or the WLC group. The Posttraumatic Stress Symptom Scale for Children (PTSS-C scale) was used in interviews with children to evaluate their symptoms and outcome. Post-treatment scores of the EMDR group were significantly lower than the WLC indicating improvement in total PTSS-C scores, PTSD-related symptom scale, and the subscales re-experiencing and avoidance among subjects in the EMDR group, while untreated children improved in PTSD-non-related symptom scale. The improvement in re-experiencing symptoms proved to be the most significant between-group difference over time. The results of the present exploratory study including a limited number of children with PTSD are encouraging and warrant further controlled studies of larger samples of children suffering from PTSD.  相似文献   
40.
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