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951.
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Abstracts     
Chronic Cough Irwin, Curley, and French: Am Rev Respir Dis 141: 640-647, 1990

The Interrelationship Among Bronchial Hyperresponsiveness, the Diagnosis of Asthma, and Asthma Symptoms Pattemore PK, Asher MI, Harrison AC, Mitchell EA, Rea HH, Stewart AW: Am Rev Respir Dis 142: 549-554, 1990

Inhaled Albuterol and Oral Prednisone Therapy in Hospitalized Adult Asthmatics: Does Aminophylline Add Any Benefit? Self TH, Abou-Shala N, Burns R et al: Chest 98:1317, 1990

Formoterol in the Treatment of Nocturnal Asthma Maesen FPV, Smeets JJ, Gubbelmans HLL, Zweers PGMA: Chest 98: 866, 1990  相似文献   
954.
The epidemiological burden of diabetes mellitus is changing the classical model of diabetes management, in which a specialist center delivers care based on registration, recall and regular review. Primary care services are progressively assuming a crucial role in screening, prevention and management of the disease. It therefore becomes critical to improve the performance of primary care providers by suitable organizational interventions. The current advances in information technology (IT) and communications technology provide new ways for coping with organizational problems, and provide the opportunity to implement complex, multifaceted interventions in a cost-effective manner. Moreover, IT enables patients to exploit new modalities of access to healthcare services.This review highlights the current situation in the implementation and delivery of IT solutions for diabetes care, and describes the trends towards more advanced and innovative IT-based services.A large number of electronic patient records (EPRs), decision support tools and telemedicine solutions have been proposed and studied but a relatively low number of them have been fully exploited in clinical practice. The main reasons for this limited dissemination are related to the complexity of establishing and evaluating interventions that have a strong impact in the process of care. However, the need for a large scale reorganization of chronic care is now pushing towards the integration of the newest IT tools with new models of diabetes management.  相似文献   
955.
The differences and similarities between intraductal papillary mucinous tumor (IPMT) and mucinous cystadenoma or carcinoma (mucinous cystic tumor; MCT) of the pancreas have been noted. The similarities include: (1) both tumors originate from pancreatic duct cells, (2) massive mucin production is found in both tumors, and (3) papillary projection is a common histological characteristic. However, there are also many differences. IPMT is most frequently found in men in their sixties, and originates in the head of the pancreas, with 62% (123/199) of tumors reported to be found in the head of the pancreas. This tumor sometimes spreads throughout the entire pancreas. The tumor itself basically is of the dilated pancreatic duct type, and the prognosis is generally good. In contrast, MCT frequently develops in women in their forties. This tumor is usually large, round, and almost totally encapsulated by fibrous tissue, with no communication with the pancreatic duct. The tumor histologically has an ovarian-like stroma. It most often develops in the body or tail of the pancreas. Invasion is often present and the operative prognosis is not good. IPMT resembles the shape of a bunch of grapes and MCT resembles that of an orange. From the differences between these two types of tumors, they are classified into different categories. With regard to therapeutic strategies for MCT, the tumor should be resected with lymph node dissection immediately when it is detected. In contrast, some patients with branch-type IPMT can be followed without surgical procedures. Because IPMT shows good prognosis and little tendency for infiltration, some kinds of organ-preserving procedures would be possible for some patients with this tumor. Such organ-preserving procedures are: duodenum-preserving pancreas head resection, spleen-preserving distal pancreatectomy with conservation of the splenic artery and vein, and so on.  相似文献   
956.
Background. Proximal tubular epithelial cells express a surface C3-convertase activity which induces C fixation and insertion of the C5b-9 membrane attack complex (MAC) into the cell plasma membrane. The physiopathological consequences of this phenomenon are unknown. Methods. The effect of C fixation on the production of inflammatory mediators by human proximal tubular epithelial cells in culture was explored. Results. Proximal tubular epithelial cells incubated with a sublytic amount of normal human serum as a source of C, but not with heat-inactivated human serum, showed a time-dependent calcium influx and a concomitant release of 14C-arachidonic acid (14C-AA). Eicosanoid synthesis following the arachidonic acid mobilization was studied as prostaglandin E2 release. Mg2+/EGTA, which did not prevent C activation by the C3-convertase, and p-bromodiphenacyl bromide, a phospholipase A2-inhibitor, inhibited mobilization of 14C-AA. These results suggest the activation of an extracellular Ca2+-dependent, phospholipase A2. Complement fixation was associated with the synthesis of proinflammaotry cytokines such as IL-6 and TNF-&agr;. Experiments with C6-deficient sera indicated that the release of 14C-AA and the production of cytokines were dependent on the insertion of the terminal components of complement in the plasma membrane. Indeed, the reconstitution of normal haemolytic activity of C6-deficient sera with purified C6 restored also the release of 14C-AA and the production of cytokines. Conclusion. In vitro complement activation on the proximal tubular cell surface triggers the generation of proinflammatory mediators, which may potentially contribute to the pathogenesis of tubulointerstitial injury.  相似文献   
957.
Purpose To compare the differences in practice and outcome of all radiologically and surgically placed central venous catheters retrospectively over a 2-year period simultaneously, at a single institution. Methods A total of 253 Hickman catheters were inserted in 209 patients; 120 were placed radiologically in 102 patients and 133 were placed surgically in 107 patients. The indication was chemotherapy in 76% of radiological and in 47% of surgical cases; the remainder were for total parenteral nutrition and venous access. Results There were 6 (4.5%) primary surgical failures and a further 17 (13%) surgical cases requiring multiple placement attempts. Pneumothorax occurred once (0.8%) surgically and four times (3.3%) radiologically. There were no radiological primary misplacements but there were five (3.7%) surgical ones. Catheter or central vein thrombosis occurred in four (3.3%) radiological and five (3.7%) surgical cases. The rate of infection per 1000 catheter-days was 1.9 in radiologically placed catheters and 4.0 in surgically placed ones (p<0.001). Average catheter life-span was similar for the two placement methods (100±23 days). Conclusion Radiological placement is consistently more reliable than surgical placement. There are fewer placement complications and fewer catheter infections overall.  相似文献   
958.
The Kasabach-Merritt syndrome is characterized by thrombocytopenia and localized coagulopathy associated with a hemangioma. Most techniques applied to eradicate the tumor or accelerate its involution (surgery, radiation therapy, embolization) are invasive and require transfusion of large amounts of blood products. In some cases, medical treatment is the only alternative. Efficacy of steroids and antifibronolytic agents has already been described, but even this approach is associated with the administration of blood products. We report two cases of infants with Kasabach-Merritt syndrome associated with cardiac and hepatic hemangiomas. At admission, both had signs of cardiac failure. They were successfully treated with prednisone and epsilon-aminocaproic acid (EACA). Blood products were not required once the diagnosis was made. These observations have important implications for the management of patients with Kasabach-Merritt syndrome because they show that even in severe cases blood transfusions can be avoided by the use of prednisone and EACA.  相似文献   
959.
The variation in mortality rates among hospitals has often been described informally as having three major components: patient severity, quality of care and random variation. These informal concepts are characterized formally by partitioning sums of squares and finding their expected values. The partition relates to commonly used tests for whether individual hospitals have unusual mortality rates. Application of the partition to the hospital mortality reports by the Health Care Financing Administration shows that their models for patient risk account for about one-half the variation among hospital mortality rates. An example using clinical measures of severity accounts for about two-thirds of mortality variation among hospitals.  相似文献   
960.
Both radionuclide angiography and myocardial perfusion imaging provide important insights that determine the management of patients with stable coronary artery disease. Both nuclear cardiology procedures have clearly demonstrated use in the noninvasvie identification of severe (left main or three-vessel) coronary artery disease and the noninvasive assessment of prognosis and thereby determine which patients should be sent to coronary angiography. Both radionuclide angiography and myocardial perfusion imaging provide prognostic information that is independent of resting left ventricular function and coronary anatomy and thereby influence the decision regarding which patients should be sent to coronary revascularization. This review considers the evidence supporting the uses of these nuclear cardiology procedures and provides suggestions regarding their cost-effective application.  相似文献   
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