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101.
Swett  HA; Fisher  PR; Cohn  AI; Miller  PL; Mutalik  PG 《Radiology》1989,172(2):487-493
Conventional computer-based medical expert systems deliver advice to physicians as written text. While such advice is useful, it has distinct limitations in a visually oriented discipline such as diagnostic radiology, in which decisions often depend on pattern recognition and appreciation of subtle morphologic features. The authors developed a prototype expert computer system, IMAGE/ICON, which displays groups of images sorted into a series of axes based on different ways in which they may be similar. They may share a common feature, group of features, causes, or clinical setting. IMAGE/ICON may display examples of morphologic variations of a dominant finding or a spectrum of abnormalities seen in an specific disease or group of diseases. The system also assembles a written analysis of key features of a case. Such a tool may be useful as a diagnostic aid or for continuing medical education. It is likely to have particular impact in the form of an intelligent radiologic workstation, as picture archiving and communication systems become available.  相似文献   
102.
Physicians often have to perform a lumbar puncture to ascertain the diagnosis in patients with meningeal signs, because of the serious consequences of missing bacterial meningitis The aim of this study was to derive and validate a clinical rule to predict bacterial meningitis in children with meningeal signs, to guide decisions on the performance of lumbar punctures. Information was collected from records of patients (aged 1 mo to 15 y) consulting the emergency department of the Sophia Children's Hospital between 1988 and 1998 with meningeal signs. Bacterial meningitis was defined as cerebrospinal fluid (CSF) leucocyte count >5 cells μl?1 with a positive bacterial culture of CSF or blood. The diagnostic value of predictors was judged using multivariate logistic modelling and area under the receiver operating characteristic curves (ROC area). In the derivation set (286 patients, years 1988–1995) the duration of the main complaint, vomiting, meningeal irritation, cyanosis, petechiae and disturbed consciousness were independent clinical predictors of bacterial meningitis. The ROC area of this model was 0.92. The only independent predictor from subsequent laboratory tests was the serum C‐reactive protein concentration, increasing the ROC area to 0.95. Without missing a single case, this final model identified 99 patients (35%) without bacterial meningitis. Validation on 74 consecutive patients in 3 subsequent years (1996–1998) yielded similar results. Conclusion: This prediction rule identifies about 35% of the patients with meningeal signs in whom a lumbar puncture can be withheld without missing a single case of bacterial meningitis. For the individual patient this prediction rule is valuable in deciding whether or not to perform a lumbar puncture.  相似文献   
103.
Pediatric blood transfusion practice in a tertiary-care pediatric hospital was evaluated retrospectively by using the technique of criteria mapping. A total of 630 transfusion episodes involving red cell concentrates, frozen plasma (plasma frozen within 24 hours of collection), platelet concentrates, and albumin were reviewed: 243 (86.2%) were reviewed only by a technical assistant, and 87 (13.8%) required additional physician review. Of these, 138 were red cell concentrate transfusions: 79.7 percent of that group were considered appropriate, 11.6 percent of unknown benefit/risk ratio, 5.8 percent inappropriate, and 2.9 percent impossible to evaluate. Some 246 frozen plasma transfusions were reviewed: 42.3 percent were considered appropriate, 32.5 percent of unknown benefit/risk ratio, 17.5 percent inappropriate, and 7.7 percent impossible to evaluate. A total of 139 platelet concentrate transfusions were reviewed: 64.7 percent were considered appropriate, 16.5 percent of unknown benefit/risk ratio, 10.1 percent inappropriate, and 8.6 percent impossible to evaluate. Some 107 albumin transfusions were reviewed: 90.6 percent were considered appropriate, 1.9 percent inappropriate, and 7.5 percent impossible to evaluate. The criteria maps developed for this study were easy for the technical assistant to use, and areas of appropriate and inappropriate pediatric transfusion practice were clearly identified.  相似文献   
104.
营养支持在急性重症胰腺炎患者中的应用及护理   总被引:5,自引:0,他引:5  
目的探讨对急性重症胰腺炎(ASP)患者施行肠内肠外阶段性营养支持的效果。方法回顾性分析121例实施营养支持的ASP患者资料,包括观察患者营养支持时间、体质量变化、血清清蛋白、住院天数与营养支持有关的并发症。结果2例死于多器官功能衰竭,死亡率1.7%。其余119例行营养支持治疗,营养支持时间(25.6±5.1)d,其中83例体质量增加,38例体质量无明显变化;97例血清清蛋白提高,24例无明显变化。119例ASP患者均逐渐达到正氮平衡,并痊愈出院,平均住院时间为(31.5±17.1)d。发生与营养支持有关的并发症12例,其中消化不良9例,高渗性利尿3例,均治愈。结论在ASP患者营养支持的治疗和护理中,做好营养支持工作是治愈ASP的重要措施。  相似文献   
105.
Discrepancies in reverse ABO typing due to prozone   总被引:5,自引:0,他引:5  
Three group O sera manifesting prozone in reverse ABO tests are reported. All were implicated in erroneous blood typing results. One sample failed to react with A1 red cells (RBCs) in immediate-spin (IS) tests, had anti-A and -B titers of 8192 and 2048, respectively, by indirect antiglobulin technique (IAT), and was from a diabetic patient; the parenteral administration of A substance present in porcine insulin is a possible cause of hyperimmunity in this case. The second sample was from the recipient of a single unit of group B fresh-frozen plasma; the serum anti-A and -B titers were 10,240 by IAT, but only weak reactions with A1 and B RBCs were noted in routine IS reverse typing tests; the hyperimmunity in the patient concerned was likely due to crossreacting anti-A, B stimulated by B-active glycoproteins and/or glycolipids in the transfused plasma. The third serum also had anti-A and anti-B IAT titers of 10,240 but did not react with A1 and B RBCs by IS; the hyperimmunity in this case may be related to sepsis from intestinal flora carrying A- and/or B-like antigens. These antibodies lysed A1 and/or B RBCs in tests incubated at room temperature (RT) and strongly agglutinated those RBCs by IS when diluted 10-fold with saline. The absence of the prozone phenomenon in tests with RBCs suspended in diluents containing EDTA is consistent with the previously published mechanism for anti-A prozone: namely, the steric hindrance of agglutination by the C1 component of human complement.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
106.
Background: This article describes standard operating procedures (SOPs) for a computer crossmatch to replace the immediate-spin crossmatch for ABO incompatibility between patient blood samples submitted for pretransfusion testing and the blood component selected for transfusion. These SOPs were developed following recent changes to the Standards for Blood Banks and Transfusion Services of the American Association of Blood Banks (AABB). Study Design and Methods: SOPs were developed, utilizing currently available software, for pretransfusion testing. The SOP for donor unit processing entails bar code entry of the unit number, component name, and ABO/Rh type; computer entry and interpretation of serologic reactions; warning of discrepancies between bar code-entered blood type and result interpretation; and quarantine of the donor unit in such instances. The SOP for patient sample testing requires bar code entry of specimen accession number, which accesses patient demographics; computer entry and interpretation of ABO/Rh tests; repeat blood typing at the time of crossmatch if only one patient blood type is on record; and warning if there are nonconcordant current and historical blood types. The computer crossmatch SOP requires bar code entry of specimen accession and donor unit numbers; release of group O red cells pending resolution of discrepancies; and immediate-spin crossmatch during computer downtime. Tables validated on- site prompt warning messages and prevent both computer crossmatch and release if blood components of the wrong ABO type are selected. Results: These SOPs meet the requirements of the 15th edition of the AABB Standards. Projected annual time savings at this institution are > 100,000 workload recording units. Further benefits include reduced patient sample volume requirements, less handling of biohazardous material, and elimination of unwanted positive or negative reactions associated with the immediate-spin crossmatch. Release of incompatible blood components when the wrong patient blood type is on record is addressed by requiring the use of group O red cells in the absence of two concordant blood types, one of which must be from a current sample. Conclusion: A combination of existing computer programs and carefully developed SOPs can provide a safe and efficient means of detecting donor-recipient incompatibility without performance of serologic crossmatch.  相似文献   
107.
目的探讨螺旋CT多期增强扫描在胆囊癌诊断中的作用。方法对23例经病理证实的胆囊癌患者的多期螺旋CT表现进行回顾性分析。结果胆囊癌主要CT表现为胆囊壁的不规则增厚和结节状突起以及胆囊内的肿块,增强扫描强化明显且持续时间长。结论螺旋CT多期增强扫描在胆囊癌的定性诊断及了解胆囊癌的侵犯范围上具有重要作用。  相似文献   
108.
Purpose: To examine (1) the patterns of service use and costs associated with language impairment in a community cohort of children from ages 4–9 years and (2) the relationship between language impairment and health service utilisation.

Method: Participants were children and caregivers of six local government areas in Melbourne participating in the community-based Early Language in Victoria Study (ELVS). Health service use was reported by parents. Costs were valued in Australian dollars in 2014, from the government and family perspectives. Depending on age, the Australian adapted Clinical Evaluation of Language Fundamentals – Pre-school, 2nd Edition (CELF-P2) or the CELF, 4th Edition (CELF4) was used to assess expressive and receptive language.

Result: At 5, 7 and 9 years respectively 21%, 11% and 8% of families reported using services for speech and/or language concerns. The annual costs associated with using services averaged A$612 (A$255 to government, A$357 to family) at 5 years and A$992 (A$317 to government, A$675 to family) at 7 years. Children with persistent language impairment had significantly higher service costs than those with typical language.

Conclusion: Language impairment in 4–9-year-old children is associated with higher use of services and costs to both families and government compared to typical language.  相似文献   

109.
Red cells preserved in extended-storage media are the standard product dispensed by many regional blood centers. When the red cells are intended for neonatal transfusion, concern exists about the safety of the relatively high quantities of additives present in these media. Definitive studies to address these concerns are not available. Therefore, to estimate the effects of additives and to delineate circumstances in which they might be harmful, the quantities transfused in defined clinical settings were calculated, and the following recommendations are offered for transfusing infants less than 4 months of age. First, red cells preserved in extended-storage media should present no substantive risks when used for small-volume (approximately 10 mL/kg) transfusions of premature infants and can be used without additional processing. Second, the risks of the most premature neonatal patients or those with severe renal and/or hepatic insufficiency cannot be defined clearly, and, because data are not available to ensure safety for these infants, removal of the additive medium and resuspension of the red cells in saline or albumin solution immediately before transfusion are recommended. Third, following a similar rationale, it seems prudent to avoid using entire units of red cells preserved in extended-storage media in massive transfusion settings (e.g., exchange transfusion, cardiac surgery, and extracorporeal membrane oxygenation). In these settings, the preservative medium should be removed and the red cells resuspended in the fluid that is most appropriate for the procedure that is planned. It must be emphasized that these recommendations are based on calculations and hypothetical settings, not actual data. Accordingly, they are tentative and should be altered as definitive information becomes available.  相似文献   
110.
The need to detect antibodies that agglutinate and/or hemolyze red cells (RBCs) directly at 37 degrees C, but do not react in subsequently performed indirect antiglobulin tests (IATs), is of concern relative to the streamlining and automation of antibody detection methods. To determine incidence and significance of such reactions, data from 87,480 tests, which used low-ionic-strength saline, 10-minute incubation at 37 degrees C, and anti-IgG, were analyzed for unexpected antibodies. There were 3590 positive tests, of which 475 showed reactions at 37 degrees C but not in subsequently performed IATs (37 + IAT-). Of these, 196 reactions were due to autoantibodies or other factors usually considered insignificant with respect to the survival of transfused incompatible RBCs, 176 were due to alloantibodies of questionable clinical significance (M, Lea, P1, etc.), and 103 were associated with alloantibodies of potential clinical significance (63 E, 27 K, 5 Jka, 4 D, 3 cE, and 1 C). This latter reaction was seen in 72 patients, with two 37 + IAT-antibodies occurring in each of 3 patients. Of the 75 potentially significant 37 + IAT-antibodies, 57 were seen in patients recently exposed to homologous RBCs, 13 in patients with a history of transfusion and/or pregnancy, and 5 in patients with no known exposure to homologous RBCs. IAT reactivity was observed in subsequent samples with 27 of these antibodies. The predictive value of a 37 + IAT-test was 21.7 percent for a potentially significant antibody. The incidence was 0.12 percent of all tests for unexpected antibodies.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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