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91.
P C Yang  D B Chang  Y C Lee  C J Yu  S H Kuo    K T Luh 《Thorax》1992,47(5):377-380
BACKGROUND: Malignancies located in the upper middle mediastinum usually do not have a sufficiently large acoustic window to permit a conventional ultrasound guided parasternal biopsy. This study was concerned with an alternative approach whereby ultrasound is applied through the supraclavicular paratracheal window to allow percutaneous biopsy of middle mediastinal malignancies. METHODS: Fifteen patients who had upper mediastinal malignancies not in contact with the chest wall underwent real time and Doppler ultrasonographic studies by the supraclavicular approach. None of these tumours could be reached by conventional ultrasound guided parasternal biopsy. The ultrasound was scanned downwards through the supraclavicular fossa, along the acoustic window of the paratracheal soft tissue space. Percutaneous aspiration biopsy was performed with a 22 gauge needle under ultrasound guidance. If fine needle aspiration could not obtain an adequate tissue smear an 18 gauge Trucut biopsy was performed to obtain a histological diagnosis. RESULTS: Twelve of 15 mediastinal malignancies were detected by ultrasound through the supraclavicular approach. These 12 patients underwent percutaneous needle aspiration biopsy under ultrasound guidance. Four of the patients also had a Trucut biopsy because the needle aspirates from the tumours were inadequate. The needle had to pass through the jugular veins in four patients who received fine needle aspiration but in none of the patients who required a Trucut biopsy. Definite histological diagnoses were obtained in all 12 of these patients. Ten of the tumours were malignant and two benign. None of the patients developed any complication. CONCLUSIONS: Ultrasound and ultrasound guided biopsy through the supraclavicular paratracheal window provides a new approach for malignancy located in the upper middle mediastinum, which cannot be reached by conventional ultrasound guided parasternal biopsy. The diagnostic yield of this technique is high and the procedure is relatively safe.  相似文献   
92.
Lung ischemia-reperfusion (I/R) injury plays an important role in many clinical issues. A series of mechanisms after I/R has been uncovered after numerous related studies. Organ preconditioning (PC) is a process whereby a brief antecedent event, such as transient ischemia, oxidative stress, temperature change, or drug administration, bestows on an organ an early or delayed tolerance to further insults by the same or different stressors. In this study, we want to uncover the optimal thermal PC patterns that cause maximal early or delayed protective effect on the subsequent pulmonary I/R with the use of miniature pig model. Twenty-eight 15- to 20-kg weight Lanyu miniature pigs are used and divided into four groups (seven sham operation control [NC], seven PC only [PC], seven I/R [I/R], and seven PC followed by I/R [PC + I/R]). The PC was performed with the animals being anesthetized and, using an alternative hyperthermic (40 degrees C) and normothermic moist air to ventilate their lungs for 15 min, respectively, for 2 cycles, followed by I/R, which consists of 90 min of blocking the perfusion and ventilation of the left lung followed by 240 min of reperfusion. Control animals had a thoracotomy with hilar dissection only. Indicators of lung injury included hemodynamic parameters, blood gas analysis, histopathological (lung pathology, wet/dry weight ratio, myeloperoxidase assay), and molecular biological profiles (interleukin-1beta [IL-1beta], IL-6, tumor necrosis factor-alpha by enzyme-linked immunosorbent assay analysis). Lung tissue heat shock protein 70 (HSP-70) expression was also detected by Western blotting. This model of lung I/R induced significant lung injury with pulmonary hypertension, increased pulmonary vascular resistance, and pulmonary venous hypoxemia at the ischemia side, increased pulmonary tissue injury score and neutrophil infiltration, increased wet/dry ratio, myeloperoxidase assay, tumor necrosis factor-alpha, IL-1beta, and IL-6 assay. This type of thermal PC would not injure the lung parenchyma or tracheal epithelium. Moreover, it could attenuate the I/R-related lung injury, with some of these parameters improved significantly. Increased expression of HSP-70 was also found in the group of PC plus I/R than the I/R only. Less prominent and transient increase in expression of HSP-70 was found in the PC group. We concluded that the intratracheal thermal PC can effectively attenuate I/R-induced lung injury through various mechanisms, including the decrease of various proinflammatory cytokines. The mechanism of its protective effect might be related to the increased expression of HSP-70.  相似文献   
93.
94.
Flying foxes belonging to the genus Pteropus are known to be reservoirs of zoonotic viruses. In this study, we describe the isolation of Pteropine orthoreovirus (PRV) from rectal swab samples of Pteropus vampyrus in Indonesia. PRV is an emerging zoonotic respiratory virus that can be transmitted from bats to humans. Rectal swabs (n?=?91) were screened by PCR for PRV and 10 (11%) were positive. Phylogenetic analysis based on nucleotide sequences indicated that the S2, S3, S4, M3, L2, and L3 segments of one isolate (Garut-69) were closely related to previously isolated strains in Indonesia. The remaining gene segments showed both similarity and genetic divergence with other PRV strains, suggesting that re-assortment events had occurred. This is the first report of PRV infection to P. vampyrus in West Java, Indonesia.  相似文献   
95.
Patients with solid tumors are increasingly being treated by autologous bone marrow transplantation (BMT). Although response rates appear to be increased, disease recurrence is the commonest cause of treatment failure. Whether relapse is entirely due to residual disease in the patient or arises also from infiltrating malignant cells contained in the autologous marrow transplant has not been resolved. If the latter explanation is correct, then purging would be required as part of the transplantation procedure. We used retrovirally mediated transfer of the neomycin-resistance gene to mark BM harvested from eight patients with neuroblastoma in clinical remission. The marked marrow cells were subsequently reinfused as part of an autologous BMT. At relapse, we sought the marker gene in malignant cell populations. Three patients have relapsed, and in each the marker gene was detected by phenotypic and genetic analyses of resurgent malignant cells at medullary and extramedullary sites. Analysis of neuroblast DNA for discrete marker gene integration sites suggested that at least 200 malignant cells, each capable of tumor formation, were introduced with the autologous marrow transplant and contributed to relapse. Thus, autologous BMTs administered to patients with this solid tumor may contain a multiplicity of malignant cells that subsequently contribute to relapse. The marker-gene technique we describe should permit evaluation of the mechanisms of relapse and the efficacy of purging in patients receiving autologous marrow transplantation for other solid tumors that infiltrate the marrow.  相似文献   
96.
Nauseef  WM; Clark  RA 《Blood》1986,68(2):442-449
We describe a system for analysis of the intracellular pathways in the biosynthesis and packaging of functionally important proteins in human myeloid cells. The human promyelocytic cell line HL-60 was used since peripheral blood neutrophils are terminally differentiated and do not actively synthesize protein. Cells were disrupted by nitrogen cavitation and subcellular organelles in postnuclear supernatant separated on a discontinuous gradient of Percoll modified to resolve organelles important in protein synthesis. This Percoll gradient separated azurophilic granules from less dense organelles and partially separated the less dense organelles from one another. Approximate densities of organelles identified by electron microscopy and by biochemical markers are azurophilic granules, 1.102 g/mL; endoplasmic reticulum, 1.039 g/mL; Golgi apparatus, 1.032 g/mL; and plasma membrane, 1.027 g/mL. We validated the utility of this method of subcellular fractionation by examining intracellular transport of myeloperoxidase, a myeloid lysosomal enzyme present in azurophilic granules. The subunits of mature myeloperoxidase (molecular weight [mol wt] = 59,000 and 13,500) cosediment with biochemical markers for lysosomes, whereas the large-mol wt (89,000) precursor forms cosediments with biochemical markers of less dense organelles. Within the limits of assay sensitivity, the 89,000-mol wt precursor is enzymatically inactive and has no spectral evidence for a heme group, suggesting that precursors of myeloperoxidase may undergo proteolytic maturation in a prelysosomal compartment with concomitant incorporation of a heme group and acquisition of enzymatic activity. This system of analysis should be suitable for the identification, subcellular localization, and maturational analysis of other myeloid lysosomal enzymes as well as functionally important membrane proteins.  相似文献   
97.
Stevenson  KB; Clark  RA; Nauseef  WM 《Blood》1989,74(6):2136-2143
Erythrocytes possess a well-characterized submembranous filamentous network which interacts with transmembrane glycoproteins and is composed primarily of spectrin, ankyrin, band 4.1, and short actin filaments. An analogous structure was recently described in platelets. Human polymorphonuclear leukocytes (PMNs) were examined for the presence and plasma membrane association of similar proteins. Isolated PMNs, free of contamination with erythrocytes or platelets, were disrupted by nitrogen cavitation and separated into subcellular organelles on a discontinuous Percoll gradient. Detergent lysates of plasma membrane vesicles, but not azurophilic or specific granules, contained insoluble actin filaments and associated proteins. Immunoblots of detergent-insoluble plasma membrane fractions contained proteins recognized by antibodies to brain fodrin and erythrocyte band 4.1, whereas blots probed with antibodies to erythrocyte spectrin and ankyrin were negative. Fodrin and band 4.1 were not detected in granule fractions, but some fodrin was present in the cytosol. The association of proteins related to fodrin and band 4.1 with the plasma membrane suggests that PMNs contain a submembranous skeleton structurally analogous to that of erythrocytes and platelets. The specific function of these proteins and their structural organization in human PMNs await further study.  相似文献   
98.

Background  

Cross-sectional studies have reported associations between social support and health, but prospective evidence is less conclusive. This study aims to investigate the associations of positive and negative experiences of social support with current and future lifestyle factors, biological risk factors, self-perceived health and mental health over a 10-year period.  相似文献   
99.

Purpose  

To evaluate the psychometric properties and gender invariance of the Chinese version of the Pediatric Quality of Life Inventory (PedsQL) for 8- to 12-year-olds.  相似文献   
100.
Chen KY  Hsueh PR  Liaw YS  Yang PC  Luh KT 《Chest》2000,117(6):1685-1689
STUDY OBJECTIVES: To provide an updated evaluation of the bacteriology of acute thoracic empyema for more efficacious treatment. DESIGN:: The medical and microbiological records of all patients who received a diagnosis of acute thoracic empyema were reviewed. Based on the bacteria isolated from the pleural fluid, the patients were classified into the following four groups: aerobic or facultative Gram-positive; aerobic Gram-negative; anaerobic; and mixed. SETTING: A university-affiliated tertiary medical center. PATIENTS AND METHODS: From January 1989 to December 1998, 171 patients with a diagnosis of acute thoracic empyema were treated. A comparative analysis of the isolates from pleural effusions, the mean length of hospital stay, the mean duration of chest tube drainage, the mean duration between the onset of symptoms and the establishment of diagnosis, treatment efficacy, and the need for subsequent intervention was performed. RESULTS: A total of 163 microorganisms were isolated from the pleural fluid of 139 patients. These patients were classified according to the following types of isolates: aerobic or facultative Gram-positive (n = 47); aerobic Gram-negative (n = 59); anaerobic (n = 14); and mixed (n = 19). Klebsiella pneumoniae was the most commonly isolated pathogen (24. 4%) and was strongly associated with a diagnosis of diabetes mellitus. The mortality rate of patients with aerobic Gram-negative bacilli isolated was the highest (22.0%), followed by those with mixed pathogens isolated (15.7%), aerobic or facultative Gram-positive (6.4%), and anaerobic (0%). CONCLUSIONS: The increasing incidence of acute thoracic empyema caused by Gram-negative bacilli, especially by K pneumoniae, has become an increasing problem. The isolation of aerobic Gram-negative bacilli or multiple pathogens from pleural fluid is associated with a poor prognosis and indicates a need for more aggressive antimicrobial chemotherapy.  相似文献   
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