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2.
The effect of a newly developed patellar realignment brace was evaluated in 21 patellofemoral joints (19 patients) with patellar subluxation (13 joints with lateral subluxation and eight with medial subluxation) by using active-movement, loaded kinematic magnetic resonance (MR) imaging. Sixteen patellofemoral joints (76%) demonstrated a qualitative correction of or improvement in patellar subluxation (ie, centralization of the patella or a decrease in the displacement of the patella) after application of the brace. Four of the five “failures” occurred in patellofemoral joints that had patella alta and/or dysplastic bone anatomy. These results indicate that the patellar realignment brace was able to counteract patellar subluxation in the majority of patellofemoral joints studied, as shown by active-movement, loaded kinematic MR imaging. This brace appears to be useful for conservative treatment of patients with patellofemoral joint pain secondary to patellar malalignment and maltracking.  相似文献   
3.
In order to provide a precise lymph node mapping during lung cancer surgery a sterilizable plastic tray moulded in the shape of the mediastinum and lungs is presented by the author. The device makes lymph node mapping simpler, safer, quicker and methodically more structured. A positive impact is expected as a result of usage of the device from making pathologist's work easier and facilitating the flux of information on the surgeon-pathologist-oncologist-pneumonologist chain to be more disinformation-free.  相似文献   
4.
Current surgical treatment of thoracic empyema in adults.   总被引:1,自引:0,他引:1  
A review of the recent literature on treatment modalities of adult thoracic empyema was conducted in order to expose the controversies and verify where consensus exists. Critical reading filtered through clinical experience was the method followed. The roles of surgical drainage, lavage techniques, debridement via VATS, decortication, thoracoplasty and open window thoracostomy were considered using the Oxford Center of Evidence Based Medicine criteria. The roles of the different therapeutical modalities were interpreted in the light of the triphasic nature of empyema thoracis. The randomised controlled trials came up with conflicting results. With two exceptions all of the papers reviewed provide level (2b) or below evidences. The lack of a single ideal treatment modality or policy reflects the complexity of the diagnosis and staging of this heterogeneous disease. Basic elements of intervention--drainage, different evacuation techniques, decortication, thoracoplasty and open window thoracostomy--are well-established technical modalities; however, neither a universally acceptable primary modality nor the gold standard of their sequence is available. Drainage remains to be the initial treatment modality in Phase I disease. Debridement via VATS is a safe, reliable and efficient method in the fibrinopurulent phase. Organised pleural callus requires formal decortication. Open window thoracostomy is a simple and safe procedure for high-risk patients and results in quick detoxication. Thoracoplasty kept its final role in pleural space management. Acute postoperative bronchial stump insufficiency requires immediate surgery. Evacuation of toxic material is mandatory. No single-stage procedure offers a solution. An optimised agressivity treatment modality should be tailored to the condition of the patient and to the potential of the persisting cavity. Decision-making involves a triad consisting of the aetiology of empyema (i.e. primary vs secondary), general condition of the patient and stage of disease, while considering the triphasic nature of development of thoracic empyema. The current attitudes show that the present concepts are based mainly on expert opinion. Flexibility and patience on behalf of the surgeon and nursing staff, the patient and the hospital management, as well as a good understanding of the complexity of this condition are the cornerstones of the treatment. No exclusive sequence of procedures leading to a uniformly predictable successful outcome is available. Individualised approaches can be recommended based on institutional practice and local protocols. Thoracic empyema in general seems to remain resilient to fit completely into the categories of evidence-based medical approach.  相似文献   
5.
Cerebrospinal fluid 5-hydroxyindoleacetic acid (CSF 5HIAA), homovanillic acid, and tryptophan were measured in 33 depressed, 36 alcoholic, and 32 neurological control female patients selected by strict operational criteria and investigated under controlled circumstances. Plasma total tryptophan was also measured in blood samples taken simultaneously with lumbar punctures. A multivariate regression analysis was done to discover the effect of age, height, and body weight on these four biochemical measures. Only CSF 5HIAA was significantly dependent on the nonspecific patient variables: height, but neither age nor weight, accounted for more than 10% of the variance of 5HIAA. The same analysis was carried out in all three separate patient groups: the relationship between height and CSF 5HIAA was present throughout, and only 2 of 12 correlations proved to be non-homogeneous. To demonstrate the significantly of these clinical parameters a multivariate analysis of covariance was done to eliminate their effect on the four biochemical variables. As a result significant differences emerged in CSF 5HIAA and total plasma tryptophan for some of the patient groups which were not demonstrable without this correction.  相似文献   
6.
Psychological distress was observer-rated with the Brief Psychiatric Rating Scale (BPRS) and self-rated with the Symptom Questionnaire (SQ) every other week for a 6-month period in 9 apparently remitted bipolar patients attending a lithium clinic. Substantial clinical fluctuations in psychopathology were observed with both rating methods. Compared to normal control subjects, patients suffering from bipolar disorder displayed significantly higher BPRS and SQ anxiety, somatization and total distress scores.  相似文献   
7.
Multidrug resistance ABC transporter Pdr5p of Saccharomyces cerevisiae is particularly important due to its ability to export a wide range of unrelated substrates. To clarify its function, we generated Pdr5p mutants by random mutagenesis and screened for mutants with altered drug specificity in vivo by using 5 drug compounds. Nine point mutations that caused significant changes in drug specificity distributed throughout the length of Pdr5p, namely, in the extracellular, transmembrane or cytoplasmic regions of the transporter. We then investigated their effects upon drug resistance, using 36 chemically related or distinct substrates. From this study, overall geometry of the Pdr5p was suggested to contribute in acquiring the enormous range of drug specificity. Based on their ability to inhibit the growth of the mutant strains, the 36 tested drugs were classified into: drugs to which the mutants responded differently (Group 1), drugs to which all the mutants showed sensitivity (Group 2), and drugs to which all the mutants exhibited resistance (Group 3). The ability of the compounds to be partitioned to the plasma membrane seemed an important factor for recognition by Pdr5p.  相似文献   
8.
The Schizosaccharomyces pombe rad51+ and dmc1+ genes code for homologues of the Escherichia coli recombination protein RecA. Deletion of rad51+ causes slow growth, retardation of cell division and a decrease in viability. rad51 cells have a defect in mating-type switching. The DNA modification at the mating-type locus required for mating-type switching contributes to slow growth in the rad51 mutant. Cell mating is reduced in crosses homozygous for rad51. Ectopic expression of the dmc1+ gene allowed us to demonstrate that the reduction in meiotic recombination in dmc1 mutants is not caused by a disturbance of rad24 expression from the dmc1-rad24 bicistronic RNA. We describe the functional defects of terminally epitope-tagged Dmc1 and Rad51 and discuss it in terms of protein interaction. Presumptive Rad51 and Dmc1 foci were detected on spreads of meiotic chromatin.  相似文献   
9.
The prominent role of plasma fibronectin (pFN) in the host defense system as an opsonin for gelatin (collagen)-coated colloids has been established. In the present study we investigated the interaction of pFN and membrane isolates from cells devoid of collagen, as well as several tissues. In a liver slice assay system it was shown that subcellular membrane fractions from lung macrophages, peritoneal exudate cells, spleen, tests, and liver were able to competitively inhibit the pFN-mediated uptake of 125I-gelatin coated latex beads (gLtx) at low concentrations. Endocytosis of 125I-labeled membrane isolates by macrophage monolayers was also promoted by addition of pFN. In an attempt to characterize the membrane component(s) interacting with pFN, it was found that mild extraction procedure with 1 M KBr could release a significant amount of this inhibitory activity. Further studies demonstrated that the agent(s) responsible for inhibition of gLtx uptake was heat sensitive, not altered by trypsin treatment, and did not contain actin, a protein known to interact with pFN. This work indicates that pFN interacts specifically with an as yet unknown membrane component(s) and that such interaction will promote clearance of cellular debris by macrophages. This suggests that pFN may be an important opsonin for the reticuloendothelial system in clearance of collagenous and noncollagenous cellular debris once they are exposed to interact with it.  相似文献   
10.
The activin type II receptorgene (ACTRII) is mutated in 58.1% of microsatellite-unstable (MSI-H) colorectal cancers and is a close relative of the TGFbeta-1 type II receptor, which is known to be involved in both MSI-H and non-MSI-H colorectal carcinogenesis. We therefore sought to determine whether ACTRII was involved in non-MSI-H colorectal cancers. We evaluated ACTRII inactivation by allelic deletion, loss of mRNA expression, or somatic mutation in 51 non-MSI-H colon cancers. Loss of heterozygosity (LOH) at the ACTRII locus (2q23.1) was found in 9 (17.6%) of 51 primary tumors. Loss of ACTRII mRNA expression was seen in one (14.3%) of the seven LOH-positive primary tumors from which total RNA was available. We also performed DNA sequencing analysis of tumors showing LOH. One LOH-positive primary tumor exhibited a novel germline missense sequence alteration (amino acid substitution, 117 Ile to Phe) that was not found in 23 additional normal individuals, implying that this alteration is not a frequent polymorphism. We conclude that ACTRII is probably involved in both non-MSI-H and MSI-H colorectal carcinogenesis, but more frequently in the latter subgroup.  相似文献   
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