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Patellar tendon avulsion is a risk with difficult exposure in a stiff knee, patella baja or previous tibial osteotomy. We sought to define a safe amount of release of the patellar tendon insertion for such cases. Eleven pairs of fresh frozen cadaveric lower limb specimens were acquired and randomized to either intact or partial release of the distal tibial insertion. Partial release of the tibial insertion of the tendon increased lateral exposure a mean 29% ± 15% (P = 0.002) while reducing ultimate strength to a mean of 80% that of the intact contralateral tendon. Measured patella release increased lateral patella translation and can be performed without risk of catastrophic rupture with basic activities of daily living following TKA.  相似文献   
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Purpose

Maintaining target hemoglobin (Hb) with minimal variability is a challenge in hemodialysis (HD) patients. The aim of this study is to compare the long- and short-acting erythropoietin-stimulating agents such as Aranesp and Eprex in achieving these targets.

Methods

Randomized, prospective, open-labeled study of 24 weeks includes stable patients on HD >3 months, age >18 years, and on Eprex for >3 months. Patients were randomized into two groups: A-(Aranesp group):HD patients on Eprex Q TIW or BIW were converted to Aranesp Q weekly, by using the conversion factor of 200:1 and those on Eprex Q weekly to Aranesp Q 2 weeks; B-(Eprex group):patients continued on Eprex treatment. Hemoglobin target was set at (105–125 g/l). Primary end points were percentage of patients achieving target Hb, hemoglobin variability, and number of dose changes in each group.

Results

This study consisted of 139 HD patients: 72 in the Aranesp and 67 in the Eprex—mean (SD) age 54 (16.2) years, 77 (55 %) males. About 46 % were diabetic. Target Hb achieved in 64.8 % of the Aranesp and 59.7 % in the Eprex (p = 0.006). Hb variability was less frequent in the Aranesp group (p = 0.2). Mean number of dose changes was 1.3 (0.87) in the Aranesp and 1.9 (1.2) in the Eprex (p < 0.001). There was 1 vascular access thrombosis in the Aranesp and 8 in the Eprex (p < 0.001). There was no difference in hospitalization and death number between the 2 groups.

Conclusions

Aranesp Q weekly or every 2 weeks is more efficient in achieving target Hb, with less dose changes and minor vascular access complications.  相似文献   
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BACKGROUND: Patients with longstanding ulcerative colitis are at increased risk of colorectal cancer. In the literature, no agreement has yet been reached regarding prevention strategies. Our report sums up a prospective study started in 1980. METHODS: A total of 65 patients affected by ulcerative colitis for more than seven years were admitted to a regular colonoscopic and biopsy follow-up programme. RESULTS: Some 20 years after the beginning of the study, 23 (35.3%) patients have been operated upon, 2 patients have died but not from cancer 29 (44.66%) patients have abandoned the programme. Only 11 (16.9%) patients have remained under colonoscopic surveillance. CONCLUSION: These results cast some doubts on the significance of such a programme and on its long-term feasibility.  相似文献   
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Summary. Chronic lymphocytic leukaemia (CLL) is known to be a stable monoclonal neoplasm. In contrast to early studies demonstrating no more than two hybridizing immunoglobulin heavy chain bands corresponding to the two expected alleles, we have demonstrated an unexpected multiband pattern when the HindIII-digested DNA samples from 38 CLL patients were analysed by Southern blot hybridization using JH and Cμ gene probes. In order to characterize the genetic basis for the multiband pattern, we molecularly cloned the immunoglobulin heavy chain genes of one of the patients whose leukaemic DNA sample demonstrated three hybridizing JH bands and a loss of the germline band. The cloned rearranged immunoglobulin genes could be divided, based on the restriction mapping and the hybridization with the various probes, into two basic patterns representing two alleles. In one of the cloned rearranged immunoglobulin genes a secondary rearrangement occurred that resulted in the addition of 300 base-pair long sequence into the switch region, and the creation of a HindIII restriction site.
The results of the study suggest that clonal evolution occurs in some CLL, and that many of these neoplasms are indeed oligoclonal due to the accumulation of secondary genetic changes.  相似文献   
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The functional capacities of granulocytes in patients with chronic granulocytic leukemia are still a subject of controversy, probably due to the heterogeneity of the abnormalities observed from patient to patient. For a better definition of these abnormalities, 14 patients with untreated chronic granulocytic leukemia were studied. The patients were divided into three groups on the basis of the functional activities of their phagocytosing granulocytes. In four patients (group I), the granulocytes were normal in respect to particle ingestion, nitroblue tetrazolium (NBT)-stimulated reduction, cyanide-insensitive oxygen (O2) consumption, superoxide anion (O2-)-stimulated production, hydrogen peroxide (H2O2) production, and iodination. They also had a normal myeloperoxidase (MPO) content. In four patients (group III), the granulocytes were significantly defective in all of these activities. In the six remaining patients (group II), all the initial metabolic steps of the phagocytosing granulocytes (ingestion, NBT reduction, O2 consumption, O2-production, H2O2 production) were normal, as were the MPO content of the granulocytes, while iodination was strikingly decreased. These metabolic features suggested a degranulation defect which was observed ultrastructurally in the only patient studied among these six. The phagocytosing granulocytes of this patient did not degranulate and no deposits of MPO activity were seen in the phagosomes.  相似文献   
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