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81.
Hypersensitivity to the fungal antigens of Aspergillus fumigatus may result in a spectrum of immune injury collectively known as allergic bronchopulmonary aspergillosis (ABPA). This report describes a 14-yr-old boy who presented clinical findings consistent with ABPA,including a history of asthma, blood eosinophilia, serum precipitins, and IgE antibodies to Aspergillus fumigatus. Sputum Aspergillus, pulmonary infiltrates, and dual types I and III skin reactions to Aspergillus fumigatus were observed also. Pathology of the resected right upper lobe revealed severe bronchial destruction with the findings of bronchocentric granulomatosis. Noninvasive septate fungal hyphae compatible with Aspergillus were identified. Cultures from sputum and surgical specimens grew Aspergillus and Mycobacterium intracellulare avium. The PPD-B (purified protein derivative-Batty) intradermal skin test produced a 6 mm induration (PPD-S was negative). The patient's condition has been well controlled with prednisone and several antituberculous drugs. In addition, inflammatory and immunologic parameters have begun to return to normal. The relationship between ABa and the atypical mycobacterial infection is not clear. The association of ABPA with the severe bronchial destruction seen in bronchocentric granulomatosis is emphasized to alert physicans to this serious sequelae of ABa seen in the asthmatic.  相似文献   
82.
Sixty-three patients who underwent renal revascularization at the time of aortic surgery were retrospectively reviewed. These patients had significant renal artery stenosis in addition to either severe aortoiliac occlusive disease or aortic aneurysmal disease. Fifty-eight patients were hypertensive, whereas five patients were normotensive and these renal lesions were treated prophylactically. The operative mortality rate was 3%. Despite lack of selectivity in these patients with diffuse atherosclerosis, 60% (35 of 58) of the patients with hypertension could be classified as either "cured" or "improved." Patients with bilateral renal artery involvement and moderate azotemia were noted to improve with respect to renal function postoperatively. No patient has required chronic dialysis at a mean follow-up period of 22.6 months. Simultaneous aortic and renal artery surgery may be performed with low morbidity and mortality rates and produce a gratifying improvement in hypertension. Renal functional improvement and perhaps preservation of renal mass may be anticipated in selected patients.  相似文献   
83.
N-(2-mercaptoethyl)-lt3-diaminopropane (WR1065) protects againstradiation-induced cell killing and mutagenesis at the hypoxanthine-guaninephosphoribosyl transferase (HGPRT) locus in V79 Chinese hamsterhing fibroblast cells. At a concentration of 4 mM, WR1065 wasfound to be effective in protecting against radiation-inducedcell lethality only if present during irradiation, e.g., a dosemodification factor (DMF) of 1.9. No protective effect was observedif the protector was added within 5 min after irradiation or3 h later, e.g., DMFs of 1.0 and 1.1, respectively. The effectof WR1065 on radiation-induced mutation, expressed as resistanceto the cytotoxic purine analogue 6-thioguanine (HGPRT), wasalso investigated. In contrast to the treatment-schedule dependencefor protection by WR1065 against cell killing, this agent waseffective in reducing radiation-induced mutations regardlessof when it was administered. Following a dose of 10 Gy of 60Co-rays, the mutation frequencies observed per 106 survivors were77 ± 8, 27 ± 6, 42 ± 7, and 42 ±7 for radiation only, and WR1065 present during, immediatelyafter, or 3 h after irradiation. These data suggest that althougha segment of radiation-induced damage leading to reproductivedeath cannot be modulated through the postirradiation actionof WR1065, processes leading to the fixation of gross geneticdamage and mutation induction in surviving cells can be effectivelyaltered and interfered with leading to a marked reduction inmutation frequency.  相似文献   
84.
A clinical-severity staging system for patients with lung cancer   总被引:4,自引:0,他引:4  
The prognostic staging of cancer in general, and lung cancer in particular, has customarily depended mainly on morphologic distinctions. The gross anatomic extensiveness of cancers is cited with TNM stages that describe the primary tumor (T), spread to regional lymph nodes (N), and metastatic dissemination (M) to distant sites. Microscopic characteristics are cited according to the cancer's cell type (e.g., adenocarcinoma, epidermoid carcinoma) and/or grade of differentiation (e.g., well differentiated, poorly differentiated, anaplastic). Although the clinical manifestations, functional effects, and associated co-morbidity of a cancer are universally recognized as having major prognostic importance, they have not been classified with a standard system of taxonomy. When considered at all, clinical phenomena have been cited with a surrogate index of "performance status" that ignores the underlying clinical dysfunctions while being greatly affected by non-clinical phenomena, such as the patient's psychic status, economic motivations, and system of social support. The current research was done to develop a standard system of taxonomy (or "staging") for the prognostic impact of clinical distinctions in patients with primary lung cancer. Appropriate data were obtained, computer-coded, and analyzed from medical records for the complete clinical course of an inception cohort of 1266 patients who were first treated at either the Yale-New Haven Hospital or the West Haven Veterans Administration Hospital during the interval January 1, 1953-December 31, 1964. The information under analysis included clinical phenomena as well as anatomic extensiveness (TNM stage), microscopic histology, the chronometric duration of the interval from the first symptom of lung cancer to zero time, the iatrotropic reason why the patient sought medical attention, the presence of anemia, the amount of customary cigarette use, and the conventional demographic data for age and gender. The main clinical phenomena were expressed in variables for symptom pattern severity, and co-morbidity. Symptom pattern referred to the existence of specific pulmonic symptoms (e.g., hemoptysis), systemic symptoms (e.g., complaint of weight loss), and metastatic symptoms that might be mediastinal (e.g., superior vena cava syndrome), regional (e.g., the Horner syndrome), or distantly metastatic (e.g., central nervous system). The symptom severity variable included the amount of weight loss, and the existence of severe dyspnea or particularly severe tumor effects (such as mental obtundation, rather than hemiparesis in patients with CNS metastasis). Prognostic co-morbidity was cited for coexisting diseases, such as recurrent myocardial infarctions, that might be more lethal than the lung cancer itself.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
85.
Abstract This project studies the use of church volunteers to reduce cardiovascular disease risk factors among their fellow church members. Our findings focus on the first 12 months of the project and address the following questions: 1) Can volunteers implement these programs with no on-site professional staff? 2) Are volunteer efforts facilitated by a local volunteer task force? and 3) Are implementation efforts aided by readily available professional staff involvement? In the intervention churches, 220 certified Risk Factor Leaders conducted 82 group programs with 740 registrants and 104 blood pressure screenings with 1,834 contacts. Our study shows volunteers to be effective implementers of heart health programs in churches. The involvement of a task force seemed to facilitate volunteer recruitment. Churches with a lower level of professional involvement had more blood pressure screenings. The effect of a task force or professional assistance on other volunteer efforts did not reach statistical significance.  相似文献   
86.
To compare the effects of stage migration in the "traditional" 3-stage TNM (tumor, node, metastasis) system with those in a new "expanded" 5-stage system, which has two additional stages for the poor prognostic groups, we used both systems to classify a cohort of 178 patients with primary lung cancer. To check for migrations, the stages in both systems were first assigned using only "old" technological information and were then reassigned using all the available "new" as well as old technological data. Although the 5-stage system had more migrations than the 3-stage system, survival rates were relatively unaffected for patients in the two new stages with poor prognosis. In both TNM staging patterns, the effects of stage migration on survival statistics were most impressive in the prognostically better (TNM I and II) stages. A solution to the migration problem is offered by the "clinical severity" (CS) staging system. Like the expanded TNM system, the CS system has 5 stages and a sharp prognostic gradient among stages. The CS system, however, had fewer technology-induced stage migrations than either TNM system, and the migrations had no substantial impact on stage-specific survival results. The excellent prognostic discrimination and secular stability of the CS system make it superior to the TNM system for comparing treatment results from different eras, especially for patients with stage I and II disease.  相似文献   
87.
A highly reproducible automated procedure for quantitative analysis of serial brain magnetic resonance (MR) images was developed for use in patients with multiple sclerosis (MS). The intracranial cavity (ICC) was identified on standard dual-echo spin-echo brain MR images using a supervised automated procedure. MR images obtained from one MS patient at 24 time points in the course of a 1-year follow-up were aligned with the images of one of the time points. Next, the contents of the ICC in each MR exam were segmented into four tissues, using a self-adaptive statistical algorithm. Misclassifications due to partial voluming were corrected using a combination of morphologic operators and connectivity criteria. Finally, a connectivity detection algorithm was used to separate the tissue classified as lesions into individual entities. Registration, classification of the contents of the ICC, and identification of individual lesions are fully automatic. Only identification of the ICC requires operator interaction. In each MR exam, the program estimated volumes for the ICC, gray matter (GM), white matter (WM), white matter lesions (WML), and cerebrospinal fluid (CSF). The reproducibility of the system was superior to that of supervised segmentation, as evidenced by the coefficient of variation: CSF supervised 45.9% vs. automated 7.7%, GM 16.0% vs. 1.4%, WM 15.7% vs. 1.3%, and WML 39.5% vs 52.0%. Our results demonstrate that this computerized procedure allows routine reproducible quantitative analysis of large serial MRI data sets.  相似文献   
88.
Recent advances in the management of patients with suspected VTE have resulted in improvements in the diagnostic testing accuracy and the development of management algorithms that are safer and more accessible. Ongoing clinical trials are evaluating whether these diagnostic management strategies can be made even simpler and less expensive. Diagnostic procedures for VTE continue to be refined, and modalities, such as magnetic resonance imaging and spiral CT, have the potential to further increase the accuracy of the investigation approach. There is still need to improve management strategies for the diagnosis of recurrent venous thrombosis and to determine whether diagnostic testing results may be correlated with long-term patient treatment needs.  相似文献   
89.
Expansion of the world's elderly populations has increased concerns about aging-related medical disorders like Alzheimer's disease and other dementias. In the United States, one fourth of those older than age 65 and at greatest risk for developing dementia live in rural environments that may influence its manifestation. The objectives of this study were to determine the need for and potential benefits of further epidemiological research concerning dementia and similar disorders in rural U.S. populations and to identify pertinent methodological issues related to rural dementia research. This study employed a National Library of Medicine (MEDLINE) document search based on the key words "cognitive disorders," "dementia," "Alzheimer's disease," and "rural," followed by recovery of literature resources references in the bibliographies of selected articles. Nineteen studies focusing on dementia or related disorders in rural settings have been reported from around the world. While four of these were conducted in the United States, only one rural dementia prevalence study has been undertaken in this country. Because of methodological variability, comparisons of prevalence estimates between these rural studies, as well as with those from urban investigations, is difficult. Nonetheless, there is reason to believe that certain potentially dementing illnesses are more common in rural populations. There is also evidence to suggest that the screening instruments commonly used in such studies tend to misclassify rural elders as "false positive" dementia cases. Information regarding dementing disorders, particularly Alzheimer's disease, in rural populations is scarce. Preliminary observations that dementia may be more common in rural settings and that rural families are more likely to maintain their dementing elders in the community imply that further rural dementia research could yield important insights into the risk factors for these illnesses, the variables influencing their course, and the methods by which they can be more effectively managed. A determination of the reliability and validity of commonly used dementia screening instruments in rural populations would represent an important advancement in this area of research.  相似文献   
90.
The secretagogue effect of histamine on calcitonin secretion has been studied in 15 patients with medullary thyroid carcinoma and compared with known stimuli: glucagon and calcium in combination with pentagastrin. The effect of concomitant histamine H2-receptor blockade on these responses has been studied in the same patients. Seven patients with undetectable basal plasma calcitonin concentrations had measurable responses to calcium/pentagastrin but not to histamine or glucagon. In the remaining eight subjects, significant responses were seen to all three test substances, calcium/pentagastrin proving to be the most potent secretagogue. Establishment of H2-receptor blockade with cimetidine had no effect on basal calcitonin concentrations and did not suppress responses to histamine, calcium or pentagastrin. The variable secretagogue effect of histamine could be mediated through H1-receptors, through nonspecific vascular dilation "washing out" preformed calcitonin, or through its destruction to varying degrees by histaminase, present in most medullary thyroid tumors. Histamine is unlikely to replace calcium/pentagastrin as the most discriminative, provocative diagnostic agent in medullary thyroid carcinoma, but correlation of secretory responses with tissue histaminase concentrations and attempted blockade with differing antihistamines will further our understanding of this tumor.  相似文献   
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