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21.

Purpose

To retrospectively determine the frequency, natural progression, radiographic characteristics, and primary cancer cell type of focal ground-glass opacities (GGOs) identified on serial radiographic examinations in patients with prior non-small cell lung carcinoma (NSCLC) resection.

Methods

One thousand three hundred and seventy-nine CT examinations in 154 patients with NSCLC resection between 1997 and 2008 were reviewed by two radiologists to determine the frequency of postoperative focal GGOs. Percentages, imaging characteristics and primary cancer cell types of GGOs that persisted, resolved, or resected were recorded. For persistent GGOs, growth rate was determined.

Results

Of 154 patients, 67 (44%) developed 174 GGO during a mean follow-up of 2.7 years (standard deviation 2.23 years, range 1 month to 10 years). Of these 174 opacities, 110 (63%) spontaneously resolved within 6 months. Of the remaining 64 lesions, 5 (3%) were resected and 59 (34%) persisted and demonstrated indolent growth with a median annual growth rate of 2.02 mm. Of the 59 persistent GGOs, 41 (69%) were nodularly shaped, 58 (95%) indistinctly marginated, 17 (29%) with pseudocavitation and 25 (42%) contained solid elements. Adenocarcinoma was the original resected cancer in more than half of these lesions (37 of 59, 63%).

Conclusions

In individuals who have undergone NSCLC resection, approximately 44% will develop focal GGO on follow-up CT examination. A majority of these GGOs will spontaneously resolve by 6 months after initial identification. As most persistent GGOs are indolent, we propose an initial 6-month interval reimaging once postoperative GGOs are detected followed by subsequent annual surveillance.  相似文献   
22.
Pressure-flow studies in man during atrial fibrillation   总被引:4,自引:2,他引:4       下载免费PDF全文
In 13 patients who had atrial fibrillation the ascending aortic pressure-flow relationships were measured by the pressure gradient technique. Both the pressure and flow curves were similar in contour to ones previously obtained by this method. From these recordings, relationships between the phases of systole, the ventricular filling time, and various derived parameters of pressure and flow such as the pulse pressure, stroke volume, peak flow, stroke work, and peak power were evaluated. For stroke volumes greater than 15 cm(3) there was little change in the duration of systole in an individual patient. In each patient both the preejection period and the duration of ejection showed a good correlation with stroke volume, peak flow, stroke work, and peak power. When data from all patients were examined, the relationship between stroke volume and duration of ejection was found to be curvilinear and had an overall correlation of r=0.91. There was marked variation from patient to patient in duration of both the preejection period and systole. Similar correlations between the phases of systole were noted with peak flow, peak power, and stroke work. A positive but mediocre correlation was found between the previous RR interval (an index of ventricular filling time) and the subsequent stroke volume. The correlation, in six patients, between two previous RR intervals and stroke volume was considerably better. The relationship between the pulse pressure and stroke volume was reasonably close except in one patient; however, the group correlation was poor due to differences between individuals.  相似文献   
23.
MICs of imipenem, cefoxitin, cefmetazole, and amoxicillin-clavulanic acid were determined against 100 strains of Mycobacterium fortuitum and 200 strains of Mycobacterium chelonae. Imipenem and cefmetazole were more active against M. fortuitum than cefoxitin was, and imipenem (which inhibited 39% of strains at 8 micrograms/ml) was the only beta-lactam active against M. chelonae subsp. chelonae.  相似文献   
24.
Transmural recordings using plunge needle electrodes are useful in mapping ventricular tachyarrhythmia, but they interfere with activation sequences or damage the myocardium. This study evaluated the effects of insertion of 66 transmural needles on myocardial activation, structure, and function. Epicardial maps were performed at thoracotomy using a 40-electrode plaque in five mongrel dogs. Sixty-six transmural plunge needles were introduced into the anterior aspect of the septum and left ventricle. Transmural maps of unipolar electrograms were recorded every 15 minutes via 124 electrodes over a 2-hour period. Epicardial maps were repeated after the needles were removed. All recordings were performed during sinus rhythm and ventricular pacing at 300- and 200-ms cycle lengths. Gated heart pool studies were performed preoperatively and 2 weeks after thoracotomy. Programmed ventricular stimulation was performed 2 weeks after thoracotomy. In total, 15,996 electrograms were analyzed. Maximum negative dV/dt of each electrogram and the activation time at each electrode did not change significantly over the 2 hours of needle insertion. After removal of the needles, epicardial maps were unchanged compared to before needle insertion. Mean left ventricular ejection fraction 2 weeks after needle insertion was 59% versus 58% before needle insertion (P=0.9). No dogs had inducible ventricular tachycardia. Histology showed contraction bands of 0.8-mm diameter adjacent to the needle tracks but no scarring. Insertion of 66 closely spaced plunge needles did not distort epicardial or transmural maps. Multiple needles did not result in myocardial scarring, left ventricular dysfunction, or predispose to ventricular tachycardia.  相似文献   
25.
Most of the six million Americans with fibromyalgia have at least one associated syndrome which mandates specialized attention in addition to traditional therapeutic approaches. These include localized procedures, regional blocks, antiinflammatory or antimicrobial regimens, attention to non soft tissue sources of psychosocial distress, and classes of medicines not usually prescribed for fibromyalgia. The successful treatment of fibromyalgia-associated syndromes improves the symptoms, quality of life, and prognosis of fibromyalgia.  相似文献   
26.
To characterize the genomic context of New Delhi metallo-β-lactamase-1 (NDM-1) and Klebsiella pneumoniae carbapenemase (KPC), we sequenced 78 Enterobacteriaceae isolates from Pakistan and the United States encoding KPC, NDM-1, or no carbapenemase. High similarities of the results indicate rapid spread of carbapenem resistance between strains, including globally disseminated pathogens.  相似文献   
27.
In the United States, dietary reference intakes describe the relations between nutrient intakes and indicators of adequacy, prevention of disease, and avoidance of excessive intakes among healthy populations for essential nutrients but not dietary bioactive components (DBCs), whose absence from the diet is presumably not deleterious to health (i.e., does not cause a deficiency syndrome). An appropriate framework is needed for establishing recommended intakes for which public health messages and food labeling for DBCs can be derived, because their putative health benefits may not be readily defined in the context of nutritional essentiality. In addition, a myriad of factors make determining their intake and status and investigating their discrete contributions to health particularly challenging. Therefore, the ASN Dietary Bioactive Components Research Interest Section felt it worthwhile to convene a special “hot topic” session at the 2014 Experimental Biology meeting to discuss this issue and serve as a call for future scientific dialogue on establishing a framework for recommended intakes of DBCs. This session summary captures the discussions and presentations that transpired during this session.  相似文献   
28.
The Metastatic Spine Disease Multidisciplinary Working Group consists of medical and radiation oncologists, surgeons, and interventional radiologists from multiple comprehensive cancer centers who have developed evidence- and expert opinion-based algorithms for managing metastatic spine disease. The purpose of these algorithms is to facilitate interdisciplinary referrals by providing physicians with straightforward recommendations regarding the use of available treatment options, including emerging modalities such as stereotactic body radiation therapy and percutaneous tumor ablation. This consensus document details the evidence supporting the Working Group algorithms and includes illustrative cases to demonstrate how the algorithms may be applied.

Implications for Practice:

The Metastatic Spine Disease Multidisciplinary Working Group algorithms can facilitate interdisciplinary referrals by providing physicians with straightforward recommendations regarding available treatment options, including emerging modalities such as stereotactic body radiation therapy and percutaneous tumor ablation.  相似文献   
29.
Adriamycin (doxorubicin) is a potent and broad-spectrum antineoplastic agent, the clinical utility of which is limited by the development of a cumulative and irreversible cardiomyopathy. Although the drug affects numerous structures in different cell types, the mitochondrion appears to a principal subcellular target for the development of cardiomyopathy. This review describes evidence demonstrating that adriamycin redox cycles on complex I of the mitochondrial electron transport chain to liberate highly reactive free radical species of molecular oxygen. The primary effect of adriamycin on mitochondrial performance is the interference with oxidative phosphorylation and inhibition of ATP synthesis. Free radicals liberated from adriamycin redox cycling are thought to be responsible for many of the secondary effects of adriamycin, including lipid peroxidation, the oxidation of both proteins and DNA, and the depletion of glutathione and pyridine nucleotide reducing equivalents in the cell. It is this altered redox status that is believed to cause assorted changes in intracellular regulation, including the induction of the mitochondrial permeability transition and complete loss of mitochondrial integrity and function. Associated with this is the interference with mitochondrial-mediated cell calcium signaling, which is implicated as essential to the capacity of mitochondria to participate in bioenergetic regulation in response to external signals reflecting changes in metabolic demand. If taken to an extreme, this loss of mitochondrial plasticity may manifest in the liberation of signals mediating either oncotic or necrotic cell death, further perpetuating the cardiac failure associated with adriamycin-induced mitochondrial cardiomyopathy.  相似文献   
30.
It is not enough to merely manage medical information. It is difficult to justify the cost of hospital information systems (HIS) or intensive care unit (ICU) patient data management systems (PDMS) on this basis alone. The real benefit of an integrated HIS or PDMS is in decision support. Although there are a variety of HIS and ICU PDMS systems available there are few that provide ICU decision support. The HELP system at the LDS Hospital is an example of a HIS which provides decision support on many different levels. In the ICU there are decision support tools for antibiotic therapy, nutritional management, and management of mechanical ventilation. Computer protocols for the management of mechanical ventilation (respiratory evaluation, ventilation, oxygenation, weaning and extubation) in patients with adult respiratory distress syndrome ((ARDS) have already been developed and clinically validated at the LDS Hospital. These protocols utilize the bedside intensive care unit (ICU) computer terminal to prompt the clinical care team with therapeutic and diagnostic suggestions. The protocols (in paper flow diagram and computerized form) have been used for over 40,000 hours in more than 125 adult respiratory distress syndrome (ARDS) patients. The protocols controlled care for 94% of the time. The remainder of the time patient care was not protocol controlled was a result of the patient being in states not covered by current protocollogic (e.g. hemodynamic instability, or transport for X-Ray studies). 52 of these ARDS patients met extra corporal membrane oxygenation (ECMO) criteria. The survival of the ECMO criteria ARDS patients was 41%, four times that expected (9%) from historical data (p<0.0002). The success of these computer protocols and their acceptance by the clinical staff clearly establishes the feasibility of controlling the therapy of severely ill patients.Over the last four years we have refined the process which we use for generating computerized protocols. The purpose of this paper is to present the six step development strategy which we are successfully using to produce computerized critical care protocols.  相似文献   
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