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31.
The effects of cadmium sulfate on the neoblast mitotic activity in regenerating planarian Polycelis felina (Daly.) were investigated. Mitotic abnormalities and chromosomal aberrations were evaluated after 6-h treatment and 24-h recovery period. The blastema were fixed, and examined cytologically through routine lactoorceine squash preparations. Mitotic indices were also determined. Cadmium sulfate induced a dose-dependent decrease in neoblast mitotic activity, accompanied with disturbances in distribution of cells over mitotic phases. Different cytological abnormalities with varying frequency were observed. Marked mitotic depression was concentration-dependent. Toxic effects of cadmium in regenerating planarian were mainly associated with mitotic spindle disturbances. Immediately after treatment mitotic abnormalities were prevalent over chromosomal and C-mitosis was the most prominent one. After 24-h recovery period a prevalence of mitotic over chromosomal aberrations was still present in animals treated with two higher concentrations of cadmium sulfate. However, the proportions of cells with chromosome stickiness in all treated animals were significantly increased compared to their post-treatment values. Observed mitotic impairments could be related to mitotic arrest contributing to retardations and delays, especially in animals treated with the highest concentration tested. The results obtained indicated usefulness of short term invertebrate assays as an alternative to in vitro pre-screening of toxic chemicals.  相似文献   
32.
两个小样本对照试验得到的证据尚不足以说明,在Lisfranc关节损伤时,切开复位内固定术(ORIF)的治疗效果要优于I期跗趾关节融合术.  相似文献   
33.
Autologous chondrocyte implantation (ACI) relies on the implantation of in vitro expanded cells. The aim was to study the dedifferentiation of human articular chondrocytes under different cultivating conditions [days 0–10 in the primary culture (P0); passages in a monolayer from P0 to P3; monolayer vs. alginate and monolayer vs. alginate/agarose hydrogels] using real‐time PCR analysis. The relative gene expressions for collagen type I and II, aggrecan and versican were quantified and the corresponding differentiation indexes (Col2/Col1, Agr/Ver) were calculated. The values of both differentiation indexes decreased exponentially with time in the P0 monolayer culture, and continued with a significant decrease over the subsequent monolayer passages. On the contrary, the chondrocytes seeded in either of the hydrogels significantly increased the indexes compared to their parallel monolayer cultures. These results indicate that alginate and alginate/agarose hydrogels offer an appropriate environment for human articular chondrocytes to redifferentiate after being expanded in vitro. Therefore the three‐dimensional (3D) hydrogel chondrocyte cultures present not only surgical, but also biological advantage over the classic suspension–periosteum chondrocyte implantation. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:847–853, 2008  相似文献   
34.
Five-week-old female albino rats were given daily doses for 1 or 2 weeks of lead as acetate ranging from 2 μg to 40 mg by gastric intubation and sacrificed on the 8th or 15th day of the experiment. Calcium-45 and 85Sr were used as markers to assess the calcium and strontium transfer through the duodenal wall by the everted gut sac method of Wilson and Wiseman. Doses of lead acetate greater than 20 μg per day decreased the transfer of both calcium and strontium across the duodenal wall and these transfers decreased further with increased doses of lead, an effect which was independent of whether the rats were killed on the 8th or 15th day of the experiment. Doses of lead acetate greater than 200 μg per day, however, did not produce a further decrease in these transfers. The retention of both calcium and strontium in the intestinal wall was unaffected by the lead treatment.  相似文献   
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OBJECTIVES: The aim of this study is to evaluate the criterion validity and responsiveness to changes over time of the Medical Outcome Study Short Form 36 (MOS SF-36) measure. METHODS: A consecutive sample of 775 patients 16 to 78 years treated for an unintentional injury at the hospital or emergency clinic in Drammen, Norway was selected for the study. Data about activity restrictions and health status measured by SF-36 were obtained by a postal questionnaire 6-10 weeks after the injury. A follow up survey was sent 24-28 weeks later to all who reported activity restriction at the time of the first survey. Fifty two of these replied (63%). RESULTS: 469 patients responded to the survey questionnaire and of these, 82 experienced some restriction of activity. These scored lower (p < 0.01) on all eight SF-36 health dimensions (physical functioning, social functioning, role limitation (physical), role limitation (emotional), bodily pain, mental health, vitality, and general health) than the 387 patients without activity restriction. Scores on physical functioning, social functioning, role limitation (physical), bodily pain, and vitality significant improved (p < 0.01) among the 52 patients who were followed up. Scores on the other dimensions, however, showed no significant changes over time. CONCLUSION: The MOS SF-36 appears to be a valid instrument, responsive to changes in health status over time among unintentionally injured adult people. Thus it may be possible to use the SF-36 to describe changes in health due to injury. The applicability of this or similar measures for injured children remains to be established.  相似文献   
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Residual platelet reactivity (RPR) following coronary artery bypass grafting (CABG) might be related to thrombotic complications and major ischemic cardiac events. The aim of this study was to evaluate the changes in platelet reactivity monitored pre- and postoperatively using multiple-electrode aggregometry (MEA) and to propose an alternative therapeutic approach in a subgroup of patients with postoperative RPR. Ninety-nine patients undergoing elective CABG were enrolled in the study, of whom 41 (41.4%) were diabetic. Preoperatively, all patients received 100 mg acetylsalicylic acid (ASA), with 47 of 99 (47.4%) patients receiving an additional 75 mg clopidogrel (CLO). The blood samples were drawn the day before surgery, and on the first and 4th postoperative day. Platelet count and fibrinogen level were documented, as well as type and daily dose of antiplatelet therapy (APT) received pre- and postoperatively. Multiple-electrode aggregometry using tests based on arachidonic acid (ASPI test) and adenosine diphosphate (ADP test) was performed on the day before and 4 days after surgery. Preoperatively, we detected 31 of 99 (31.3%) patients with RPR (ASPI > 30 AUC). Platelet count correlated with both the ASPI (P = 0.03) and ADP (0.002) tests. Fibrinogen correlated with ADP test values (P < 0.001) and was found to have a higher level in the diabetic subgroup (P = 0.01). In comparison with preoperative results, we detected higher values of ASPI test postoperatively (P = 0.04), with 46 of 99 (46.5%) patients having RPR despite a higher dose of 300 mg ASA being administered. Postoperatively, diabetic patients had higher ASPI test values (P = 0.01), and a higher proportion of patients with RPR compared with the nondiabetic subgroup (58.5 vs 38%, P = 0.04). The subgroup of patients with detected ASPI >30 AUC at the 4th postoperative day consequently received as a part of our clinical routine an additional 75 mg CLO per day, in terms of platelet inhibition optimization. Multiple-electrode aggregometry can recognize patients with RPR during both the pre- and post-CABG period. Postoperatively administered ASA (300 mg) did not sufficiently inhibit platelet aggregation in 46.5% of post-CABG patients. In this group of patients a switch to dual APT should be considered.  相似文献   
40.
Background: Intestinal perforation caused by blunt trauma to an inguinal hernia is a very uncommon event. Case Report: We present the case of a 55-year old man who suffered trauma to the inguinal area while playing soccer and later developed intense abdominal pain with no categorical signs of peritoneal irritation. Computed tomography scan at arrival showed a right inguinal hernia, with partial protrusion of the ileum, inflammatory changes of the mesenteric fat tissue inside the hernial sac, and free intraperitoneal fluid. Several hours later he developed hypotension and fever. An emergency laparotomy was performed, revealing ileum perforation with peritonitis. Intestinal perforation was repaired without intestinal resection. After surgery, the patient developed severe septic shock with multiple organ failure. He recovered without sequelae and was discharged 3 weeks later. Conclusion: This case emphasizes the potential clinical complications associated with this condition.  相似文献   
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