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11.
In knee arthroplasty, component malpositioning seems to be a fundamental cause for failure. The degree of malpositioning is important. To investigate this degree, 86 of 137 knee arthroplasties performed with the Townley semiconstrained bicondylar prosthesis were examined after a mean follow-up period of 6.5 years (range, 5.0-8.5 years). Five arthroplasties were excluded because of aseptic loosening, but none of these showed malalignment in postoperative roentgenograms. Clinical results and the patients' reports on deterioration of prosthetic function were correlated with positioning of the prosthetic components. Total alignment between 6 degrees of varus and 7 degrees of valgus was associated with good clinical results. Total alignment of more than 7 degrees of valgus, anterior tilting of the tibial component, or positioning of the femoral component in more than 12 degrees of valgus correlated with relatively poor clinical results.  相似文献   
12.
13.
The International Classification of Functioning, Disability and Health (ICF; World Health Organization, 2001) provides an international and interprofessional scientific basis for understanding and studying health. The concept of participation plays an important role in the classification and has become a central construct in health care, rehabilitation, and in occupational therapy. The aim of this paper is to provide a critical analysis of the concept of participation in the ICF. As background, the origins and current presentation of the ICF are presented. The use and function of the ICF and the contemporary discussions regarding the classification are reviewed. An occupational perspective on participation in the ICF reveals major shortcomings regarding the subjective experience of meaning and autonomy. Furthermore, the ICF has limitations in capturing different kinds of participation in a single life situation. Following these analyses we discuss the advantages and shortcomings of using the ICF, and how an occupational perspective can contribute to an ongoing discussion about the development of the ICF.  相似文献   
14.
By an anterior approach, six pathologic dens fractures were stabilized with screws and methyl methacrylate cement. All the patients had immediate pain relief and could be mobilized without external support. Using the anterior approach, the tumor can be removed and the instability neutralized at the site of the lesion.  相似文献   
15.
A perifusion technique for microscopy with computerized detection of early changes in cell morphology during continuous perifusion was used to show that the geometry of cultured glioma cells (MG-251) changes rapidly when they are exposed to estramustine phosphate (EMP). When the cells were exposed to 20 or 40 mg l(-1) EMP, cell volume projected cell area (PCA) rapidly increased. When the Na+,K+-ATPase blocker ouabain (100 micromol l(-1)) was added to the EMP (40 mg l(-1)) perifusion, the acute EMP response was eradicated. When the PCA curve for ouabain alone was subtracted from the curve of combined ouabain and EMP perifusion, the resulting curve showed that ouabain completely blocked the EMP-induced increase in PCA. When the Na+, K+, Cl- co-transport inhibitors bumetanide (10 micromol l(-1)), or furosemide (100 micromol l(-1)), were added to EMP (40 mg l(-1)), the acute increase in PCA seen for EMP alone was also completely blocked. This study shows that inhibitors of ion transmembrane transport can modify EMP-induced cell volume increases. This may be of particular importance since the blockers have been found to interfere also with the cytotoxic function of EMP during cell culture. Thus, it is possible that cell volume changes could serve as a rapid technique for predicting the cytotoxic activity of antineoplastic drugs.  相似文献   
16.
A fluorometric microculture cytotoxicity assay was employed for the study of cyclosporin A induced cytotoxicity in tumor samples from patients with B type chronic lymphocytic leukemia (B-CLL). Tumor cells from patients with B-CLL were found to be significantly more sensitive to the cytotoxic actions of cyclosporin A than normal blood mononuclear cells and tumor cells obtained from patients with different types of acute leukemia and solid tumors. The effect of cyclosporin A on B-CLL samples could be reproduced by a non-immunosuppressive cyclosporin A analogue. One B-CLL patient treated with cyclosporin A responded with a significant decrease in tumor mass and alleviation of anemia and B symptoms. The results show that cyclosporin A and its non-immunosuppressive analogues appear selectively toxic to B-CLL cells, an observation which may have clinical implications.  相似文献   
17.
Twenty-two women were studied during laparoscopy with abdominal insufflation of carbon dioxide. A bain anaesthetic breathing circuit was used with a fresh gas flow (VFG) of 110 ml.min-1.kg-1, and controlled ventilation was applied with a minute ventilation (VE) of 175 ml.min-1.kg-1. Arterial blood gases were analysed at the end of the operation. Nineteen of the women (86 per cent) were found to have a PaCO2 within the range for normocapnia (i.e., 4.7-5.9 kPa (35-45 mmHg), two were hypocapnic with a PaCO2 of 4.4 and 4.5 kPa (33 and 34 mmHg) respectively and one was found to have a PaCO2 of 6.2 kPa (46.5 mmHg). It was concluded that the carbon dioxide absorbed from the abdomen during laparoscopy demands fresh gas flows that are higher than normally used in the Bain circuit if a PaCO2 within the normal range is to be obtained. A simultaneous increase in VFG and VE of about 45 per cent is sufficient to achieve normocapnia.  相似文献   
18.
Mixed haemadsorption should be regarded as an application of the mixed antiglobulin reaction to situations where the antigen is sessile on a glass surface. Antibody attached to the antigen when exposing the latter to an antiserum is traced by red cells carrying an antiglobulin layer which makes them adsorb to the antibody.

The indicator cells are prepared by coating them first with a layer of γ-globulin from the animal species, the antibody globulin of which they are intended to trace, and then with a layer of the corresponding antiglobulin. The most effective indicator cells were obtained by attaching antibody to natural receptors on the red cells to achieve their first coating of γ-globulin.

The preparation of indicator cells for tracing antibodies from a number of species, including human, is described.

The mixed haemadsorption technique is highly specific and has a sensitivity which is comparable to that of the most sensitive serological techniques.

Test procedures adapted for different purposes are outlined and a number of applications to experimental and clinical problems are reviewed.

  相似文献   
19.
Five gram-positive bacterial strains were selected for absorption studies of human serum samples. Strain AR1 (group A, M-type 1) and G148 (group G), with strong immunoglobulin G (IgG) binding capacities, and strain AW43 (group A, M-type 60), binding both IgA1 and IgA2, were compared with Staphylococcus aureus Cowan I and with Staphylococcus epidermidis L603. Both AR1 and G148 were capable of completely absorbing out serum IgG. In contrast, S. aureus Cowan I left a fraction unabsorbed, as expected from its known lack of IgG3 binding. Strain AW43 absorbed out all serum IgA, using a 10-microliter bacterial pellet for 20 microliter of serum. Serum IgM levels were slightly reduced by S. aureus Cowan I absorption. On the basis of the experiments, a bacterial mixture was designed consisting of S. aureus Cowan I and group A streptococcus strains AR1 and AW43, with absorption characteristics suitable for use in discriminating between early IgM and late IgG and IgA immune responses in routine serological work. A new type of bacteria-mammalian protein binding was discovered. Human serum albumin was completely absorbed out by strain G148 and to a lesser extent by strain AR1 and AW43. S. aureus Cowan I and S. epidermidis were negative. The binding capacity of G148 for albumin equalled that of Cowan I for IgG. The binding pattern of albumin to the strains was different from those of IgG, IgA, IgM, fibrinogen, haptoglobin, or aggregated beta 2-microglobulin and therefore seems to represent another type of bacterial-mammalian interaction with a specific albumin receptor on the surface of streptococci.  相似文献   
20.
Extracellular superoxide dismutase (EC-SOD) controls the availability of extracellular superoxide (O 2 - ), which is important for a variety of physiological pathways, including the primary means of inactivating nitric oxide (NO). The role of EC-SOD in neurobehavioral function has been until now unexplored. In the current studies, the phenotypic expression of genotypic alterations of EC-SOD production in mice were characterized for spatial learning and memory. Dramatic impairments in spatial learning in the win-shift 8-arm radial maze were seen in both EC-SOD knockout mice and EC-SOD overexpressing mice. The EC-SOD overexpressing mice were further characterized as having significant deficits in a repeated acquisition task in the radial-arm maze, which permitted the dissociation of long and short-term learning. Long-term learning was significantly impaired by EC-SOD overexpression, whereas short-term learning was not significantly affected by EC-SOD overexpression. NO systems have been shown to be importantly involved in learning and memory. This may be important in the current studies because EC-SOD has primary control over the inactivation of NO. We found that EC-SOD overexpressing mice were resistant to the cognitive effects of L-NAME (NG-nitro-L-arginine methyl ester hydrochloride), an NO synthase inhibitor. Decreased NO catabolism in these mice may have served to counter the effects of NOS inhibition by L-NAME. The current finding that EC-SOD levels that were either higher or lower than controls impaired learning demonstrates that the proper control of brain extracellular (O 2 - ) may be more vital than merely reduction of brain extracelluar (O 2 - ) in maintaining adequate learning function.  相似文献   
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