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991.
Rupture of the Achilles tendon is typically associated with sportive activities with increasing tendency; it occurs most commonly in the third to fourth decade of life with a male-to-female ratio of 5–10:1. Ruptures are caused predominantly by a sudden, unexpected overextension of the tendon while direct trauma is less frequent. The recommended treatment of the injury remains controversial. In Germany, due to the good functional results, the open surgical repair represents the standard therapy since many years. The open suture technique offers the advantage of a lower re-rupture rate but is associated with the risk of wound-related complications including infection. By percutaneous suture techniques a significant decrease in the rate of infections and complications in wound healing could be achieved by minimal-access with reduced soft tissue trauma; on the other hand an increased rate of lesions of the sural nerve is reported. Dynamic imaging assessment of ultrasound or MRI allows a more accurate localisation of the ruptured ends of the tendons which is the prerequisite for the non-operative primary functional treatment of Achilles tendon ruptures. This conservative treatment regime is recommended when adaptation of the ends of the ruptured tendon is possible in 20° plantar flexion of the foot. Moreover, the desired level of daily activity and the patients’ degree of compliance has to be considered. Operative management should be avoided in the elderly patient or patients with risk factors like immunosuppressive therapy, diabetes mellitus, steroid use or failure to comply.  相似文献   
992.
Our purposes were to determine the incidence of BK viruria, viremia or nephropathy with tacrolimus (FK506) versus cyclosporine (CyA) and whether intensive monitoring and discontinuation of mycophenolate (MMF) or azathioprine (AZA), upon detection of BK viremia, could prevent BK nephropathy. We randomized 200 adult renal transplant recipients to FK506 (n = 134) or CyA (n = 66). Urine and blood were collected weekly for 16 weeks and at months 5, 6, 9 and 12 and analyzed for BK by polymerase chain reaction (PCR). By 1 year, 70 patients (35%) developed viruria and 23 (11.5%) viremia; neither were affected independently by FK506, CyA, MMF or AZA. Viruria was highest with FK506-MMF (46%) and lowest with CyA-MMF (13%), p = 0.005. Viruria >/= 9.5 log(10) copies/mL was associated with a 3-fold increased risk of viremia and a 13-fold increased risk of sustained viremia. After reduction of immunosuppression, viremia resolved in 95%, without increased acute rejection, allograft dysfunction or graft loss. No BK nephropathy was observed. Choice of calcineurin inhibitor or adjuvant immunosuppression, independently, did not affect BK viruria or viremia. Viruria was highest with FK506-MMF and lowest with CyA-MMF. Monitoring and preemptive withdrawal of immunosuppression were associated with resolution of viremia and absence of BK nephropathy without acute rejection or graft loss.  相似文献   
993.
Reliable osteosynthesis techniques in the treatment of proximal tibial shaft fractures are still a problem. Intramedullary nailing leads to pitfalls in terms of delayed fracture healing or axial malalignment, while plate osteosynthesis of these fracture types may lead to implant failure. Thus, biomechanical tests to develop alternative strategies are needed to guarantee higher primary stability. Our studies in this direction demonstrate that the combination of the unreamed tibia nail (UTN) with a limited contact dynamic compression plate (LC-DCP) leads to significantly higher stability. A buttress plate together with a small external fixator can be used alternatively. By using these combined osteosyntheses, pitfalls may be avoided in most cases.  相似文献   
994.
INTRODUCTION: To plan for future acceptance and implementation of computer-related technology, it is necessary to understand orthodontists' current perceptions and attitudes toward emerging technologies. METHODS: An anonymous, self-administered, mail-out survey of Canadian orthodontists was conducted. The response rate was 45.6% (304/667). RESULTS: Most orthodontists indicated that computer technology could improve current practice efficiency and quality of patient care. Only 15% reported that digital models are quite or very useful; 73.6%, 69.1%, 55%, and 37.4% agreed or strongly agreed with using digital and electronic technology to consult with other dental specialists, other orthodontists, general dentists, and the public, respectively. Cost of the technology was reported as a significant or insurmountable obstacle by 54% of the respondents. Interprovincial legislation, unclear consultation remuneration guidelines, and lack of comfort with the technology were not perceived as significant obstacles. Only 36% reported security or privacy issues as a significant or insurmountable obstacle. CONCLUSIONS: Canadian orthodontists seem to view digital and electronic technology as useful and capable of improving their offices' efficiency and production. Although they are sensitive to some potential obstacles, they are willing to overcome these and incorporate the technology into their practices.  相似文献   
995.
996.
Glass ionomer restorative cement offers the clinician an alternative to bonded composite resin for restoration of certain lesions in primary teeth. This article details a step-by-step procedure for restoration of a smooth surface carious lesion in a primary incisor using an encapsulated glass ionomer restorative material and reviews advantages and limitations of the cement. A light-hardened glass ionomer liner/base that has proven useful as an enamel and dentin restorative is also described.  相似文献   
997.
To produce hybrids, one member of the parental line is genetically made male-sterile. This male-sterile trait is encoded by mitochondria so that it is maternally inherited. Consequently, the progeny of a male-sterile plant is fully sterile. Nevertheless, during the handling of cytoplasmic male-sterile seed stocks, some mixture with seeds of the maintainer lines can occur. Up to the present time, the only way to check the homogeneity of the cytoplasmic male-sterile seed stock was to grow the plants until flowering time. We have developed a method which can be used immediately after the harvest, allowing us to check samples from both sunflower and sugar beet. We used the mitochondrial plasmid, present only in the maintainer lines, as a probe for the total nucleic acids prepared from the cytoplasmic male-sterile seed stocks which might be contaminated. The signals compared to those of samples artificially contaminated allow us to measure as few as one male-fertile seed in 1000 seeds in a rapid and accurate manner.  相似文献   
998.
International Journal of Clinical Pharmacy - In order to calculate the minimum sterilization process conditions to obtain the generally accepted sterility level (less than 1·10?6...  相似文献   
999.
A detailed examination of quantitative relationships of pharmacological action with plasma and tissue concentrations of indomethacin has been undertaken in the rat, after single oral administration of two sustained release preparations. In this study, drug was assayed by high performance liquid chromatography, whereas antiinflammatory response was assessed through the carrageenin-induced edema test. Significant linear correlations (p less than 0.001) were found between logarithmically transformed percent inhibition of edema and logarithmically transformed plasma, as well as tissue levels of indomethacin. However, the lack of significance for partial correlation regarding tissue concentration, contrary to plasma concentration, suggests that pharmacological response is more closely related to the latter, indicating that antidematous effect is mediated via the circulating drug rather than a local action in target tissues. This assumption is further discussed from the equivalence point of view. The relevance of this type of study in the case of topical administration of indomethacin is addressed as well. Taking into account the predictive value of the rat paw edema test for clinical efficacy, relationships similar to those observed are to be expected in man. The high correlation existing between plasma concentration of indomethacin and its pharmacological effect justifies the development and use of sustained release preparations in order to improve the outcome of treatment with this nonsteroidal antiinflammatory drug.  相似文献   
1000.
Forty samples of cord blood lymphocytes were isolated from 40 normal healthy full-term newborns. The initial 20 samples were used to determine the dose-response curve of three different thymic extracts (TP-1, bovine thymic extract; TG-15-I and TG-15-II, both porcine thymic extracts) and one of renal origin (KG-1) as a control of non-lymphoid organ extract, by measuring the E-rosette T cells. Results showed that E-rosette T cells increased significantly when the thymic extract concentration was increased to 12.5 micrograms/ml. However, there was no statistical difference between TP-1, TG-15-I and TG-15-II in the increase of E-rosette-forming cells. The remaining 20 samples were preincubated with 0, 12.5, 25 or 50 micrograms/ml of thymic extracts. It was observed that the lymphoproliferation, interleukin-2 (IL-2), gamma-interferon (IFN-gamma) and tumor necrotic factor (TNF) production were all significantly increased after thymic extract treatment. No statistical difference between these three thymic preparations in the stimulation of lymphoproliferative response was found. However, among the three thymic extracts, TP-1 appears to induce the highest amounts of IL-2, IFN-gamma and TNF. Of the TG-15-I and TG-15-II, the former stimulates higher IL-2 production whereas the latter enhances IFN-gamma and TNF production. The different immunostimulating effects and potencies that these three thymic extracts showed may reflect not only the species difference but also the difference in preparation procedures. Different components in these thymic extracts may be responsible for different biological activities. Results from these comparative studies may provide useful information in future clinical trials for the treatment of the primary immunodeficiency diseases according to their pathogenesis and may also indicate a possible beneficial effect of the combination of chemotherapy and thymic extracts.  相似文献   
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