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1.
OBJECTIVE: Respiratory muscle endurance of able-bodied persons, assessed by normocapnic hyperpnoea at 70% of their maximal voluntary ventilation, usually ranges from 10 to 20 minutes. The aim of this study was to determine the level of ventilation that patients with paraplegia and tetraplegia can sustain for 10-20 minutes to later be used as the guideline for respiratory muscle endurance training. DESIGN: Pilot study; cross-over setting. SUBJECTS: Two groups, 8 patients with paraplegia and 6 with tetraplegia. METHODS: Respiratory muscle endurance tests were performed at 3 different intensities of normocapnic hyperpnoea, i.e. 20%, 40% and 60% maximal voluntary ventilation. Subjects performed partial re-breathing from a bag to assure normocapnia. Respiratory endurance was separately analysed for patients with paraplegia and tetraplegia. RESULTS: Mean respiratory endurance times were 46.0, 18.9 and 4.2 minutes at 20%, 40% and 60% maximal voluntary ventilation in patients with tetraplegia and 51.8, 38.8 and 12.2 minutes in patients with paraplegia. The duration differed significantly at 60% maximal voluntary ventilation between the groups. CONCLUSION: Minute ventilation to perform respiratory muscle endurance training can be set at around 40% of maximal voluntary ventilation for patients with tetraplegia and around 60% of maximal voluntary ventilation for patients with paraplegia, as these levels can be sustained for 10-20 minutes.  相似文献   
2.
Background: Percutaneous closed needle biopsy of musculoskeletal neoplasms has gained in popularity. However, it remains controversial whether or not to resect the needle tract for fear of a local recurrence. A single published case report exists, noting the lone tract recurrence of an extremity skeletal osteosarcoma. Methods: We report on three additional individuals who demonstrated that tract local recurrences may occur after a closed needle biopsy for nonosteosarcoma, nonextremity sarcomas. For perspective, the world literature is reviewed to identify tract recurrences for other malignancies and the results of needle biopsy in musculoskeletal neoplasms. Results: Eighty-nine percent of needle tract local recurrences occur when carcinomas are subjected to biopsy, as reported in the literature. Forty-seven cases since 1950 are described representing essentially all tumor types. The nature of musculoskeletal neoplasms makes closed biopsy more difficult than for softer, more homogeneous, and easier to access neoplasms. Conclusions: Local recurrences of sarcoma may occur in closed needle biopsy tracts. Strong consideration should be given to open biopsy and tract resection.  相似文献   
3.
At least five gene classes are amplified in the multidrug-resistant CHO cell line CHRC5. Protein products have been identified for two classes; class 2 codes for the large membrane P-glycoprotein, whereas class 4 encodes the small cytoplasmic calcium-binding protein sorcin (V19). By DNA analysis we have shown previously that these five genes are linked in two groups: class 1 + 2 + 3; and class 4 + 5. By use of in situ hybridization with complementary DNAs derived from the resistant cell line we demonstrate here that genes from both linkage groups are amplified and situated together in each of two different chromosomal regions of the resistant Chinese hamster cell line. The positions of the amplicons correspond to cytogenetically identified homogeneously staining regions in an altered 7q+ chromosome and in a rearranged Z-7 [t(3;4)] chromosome. The native genes were mapped both in the CHRC5 line and in a normal diploid Chinese hamster cell strain, CHNF 86. We confirm the position of the class 2 gene on 1q26 and we show that class 4 and 5 genes are located in the same region of 1q. We conclude that the gene classes 2, 4, and 5 are closely juxtaposed in the normal Chinese hamster genome and comprise one amplicon in resistant cells. Our results are compatible with the hypothesis that multidrug resistance is due to overexpression of P-glycoprotein genes and that the other genes amplified in the CHRC5 line are coamplified because they happen to lie close to the P-glycoprotein genes.  相似文献   
4.
CCR5Delta32 is a deletion mutation in the chemokine receptor CCR5. Liver inflammatory activity was found to be significantly reduced (P = 0.005) in Jewish Israeli patients infected with the hepatitis C virus (HCV) carrying the CCR5Delta32 allele. The CCR5Delta32 allele does not alter susceptibility to HCV infection; however, it may play a role in the progression and outcome of the disease.  相似文献   
5.
This report describes a patient who developed spasticity after a medullary infarct. No improvement in her spasticity was achieved by baclofen therapy and the side effects of the drug necessitated its gradual withdrawal. Recent reports of the success of clonidine in the management of spasticity due to spinal cord injury prompted an attempt at clonidine therapy. When clonidine therapy was initiated, the patient responded rapidly with both subjective and objective improvements in her spasticity. This case suggests a potential role for clonidine in the treatment of spasticity resulting from brainstem infarction.  相似文献   
6.
7.
CCR5Δ32 is a deletion mutation in the chemokine receptor CCR5. Liver inflammatory activity was found to be significantly reduced (P = 0.005) in Jewish Israeli patients infected with the hepatitis C virus (HCV) carrying the CCR5Δ32 allele. The CCR5Δ32 allele does not alter susceptibility to HCV infection; however, it may play a role in the progression and outcome of the disease.  相似文献   
8.
Pseudomonas pickettii caused respiratory tract colonization in five infants in the special care nursery of a Chicago hospital. All organisms had the same antimicrobial susceptibilities. Endotracheal suctioning with saline from 5-ml unit-dose vials was identified by epidemiologic investigation as a risk factor for colonization. The vials of saline were contaminated with a strain of P. pickettii having the same antimicrobial susceptibility pattern as the isolates from patients. As part of an investigation of the manufacturing plant where the saline solution was produced, P. pickettii was recovered from deionized water used to make the product and from several sites in the processing line. Bypassing of a 180 degrees F (ca. 82 degrees C) water-holding tank appeared to be temporally related to product contamination. The ability of P. pickettii to survive and grow in this solution has been demonstrated in the laboratory. This outbreak demonstrates that, despite pertinent Food and Drug Administration regulations and company programs for identifying such contamination, intrinsically contaminated solutions can occasionally reach the bedside of the patient.  相似文献   
9.
BACKGROUND: Until the mandatory introduction of viral inactivation techniques of blood plasma products in the early 1980s many recipients of these products were infected with various viral pathogens. OBJECTIVES: To determine the rate of transmission of GB virus C/hepatitis G virus (GBV-C/HGV) HCV, and HIV through non-virus-inactivated clotting factor concentrates in hemophiliacs, as well as the relation between amount of administered clotting factor and risk for GBV-C/HGV infection. STUDY DESIGN: In this cross-sectional study, we determined retrospectively the rates of infection markers for GBV-C/HGV, HCV, and HIV in a German cohort of hemophiliacs treated with documented amounts of non-virus-inactivated clotting factor concentrates (group A) and in a second group of hemophiliacs who were treated exclusively with virus-inactivated clotting factor (group B). The presence of anti-virus antibodies was determined by ELISA. Viral RNA was detected by RT-PCR. Markers for viral infections were compared to amounts of administered non-virus-inactivated clotting factor. RESULTS: Among hemophiliacs treated with documented amounts of non-virus-inactivated clotting factor the prevalence for GBV-C/HGV, HCV, and HIV was 40.3%, 98.6%, and 56.3%, respectively. In contrast to HIV, the rate of GBV-C/HGV infections did not increase with increasing amounts of consumed non-inactivated clotting factor. Even in the subgroup of heavily treated hemophiliacs the rate of GBV-C/HGV infection markers did not exceed 45%. CONCLUSIONS: The amount of non-virus-inactivated clotting factor is not predictive for the risk of GBV-C/HGV infection in hemophiliacs. Despite repeated parenteral exposure more than 55% of hemophiliacs were not infected with GBV-C/HGV. Our findings indicate a high frequency of host factors preventing parenteral transmission of GBV-C/HGV.  相似文献   
10.
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