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排序方式: 共有249条查询结果,搜索用时 218 毫秒
1.
Solitary bronchioloalveolar carcinoma: CT criteria   总被引:14,自引:0,他引:14  
The computed tomographic (CT) scans of 30 patients with solitary bronchioloalveolar carcinoma were reviewed. Common features at CT included the peripheral or subpleural location of a pulmonary mass (25 cases), pseudocavitation (18 cases), heterogeneous attenuation (17 cases), irregular margins forming a star pattern (22 cases), and pleural tags (21 cases). Using these CT criteria, four independent observers attempted to identify cases of bronchioloalveolar carcinoma from a larger sample of lung cancers and benign lesions by categorizing a series of test cases into four probability categories. Although the bronchioloalveolar carcinomas were correctly ranked in the two highest probability categories 75% of the time (in 45 of 60 cases), there was considerable overlap with other lung lesions, particularly with adenocarcinoma and large cell undifferentiated carcinoma. However, even though the typical features of bronchioloalveolar carcinoma are not invariable or highly specific, they are characteristic enough to suggest the diagnosis.  相似文献   
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Aims. Examine the relationship between buprenorphine and norbuprenorphine plasma concentrations with subject-reported withdrawalsymptomatology during buprenorphine dose induction, maintenance treatment (daily and alternate-day dosing) and withdrawal . Design. Two groups of randomly assigned subjects inducted onto buprenorphine and maintained on 8 mg daily by the sublingual route for 18 days. Group 1 continued to receive daily buprenorphine to day 36. Group 2 subjects received alternate-day dosing of buprenorphine and placebo on days 19 to 36. Both groups received placebo on days 37 to 52 . Setting. Inpatient facilities at the Addiction Research Center, Intramural Research Center, NIDA, Baltimore, MD . Participants. Eleven male, heroin-dependent volunteers participating in a research study . Intervention. Medications for treatment of withdrawal symptoms were prescribed as needed after day 39 (72 hours after the last dose of buprenorphine) . Measurements. Plasma concentrations of buprenorphine and norbuprenorphine, withdrawal symptomatology and pupil diameter . Findings. The mean steady-state buprenorphine plasma concentration (24 hours) after daily administration of sublingual buprenorphine for study days 21-35 was 0.80 ng/ml, and the mean alternate day steady-state buprenorphine plasma concentration (24 hours) was 0.77 ng/ml. Daily and alternate day steady-state norbuprenorphine plasma concentrations were 1.10 and 0.90 ng/ml, respectively. Predicted alternate day steady-state buprenorphine and norbuprenorphine plasma concentrations at 48 hours were 0.49 ng/ml and 0.57 ng/ml, respectively. Withdrawal scores varied inversely with plasma concentration. There were no significant differences between Groups 1 and 2 during steady-state (days 21-35) with regard to withdrawal scale scores or pupillary diameter. The overall, mean terminal elimination half-lives for buprenorphine and norbuprenorphine were 42 and 57 hours, respectively . Conclusions. During daily buprenorphine maintenance, plasma concentrations greater than 0.7 ng/ml of buprenorphine and norbuprenorphine were associated with minimal withdrawal symptoms. The long elimination half-life of buprenorphine suggested that increasing the buprenorphine dose with alternate-day administration may provide an effective, flexible therapy regimen for the treatment of opioid dependence.  相似文献   
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An intact enteric nervous system is required for normal gastrointestinal tract function. Several human conditions result from decreased innervation by enteric neurons; however, the genetic basis of enteric nervous system development and function is incompletely understood. In an effort to increase our understanding of the mechanisms underlying enteric nervous system development, we screened mutagenized zebrafish for changes in the number or distribution of enteric neurons. We also established a motility assay and rescreened mutants to learn whether enteric neuron number is correlated with gastrointestinal motility in zebrafish. We describe mutations isolated in our screen that affect enteric neurons specifically, as well as mutations that affect other neural crest derivatives or have pleiotropic effects. We show a correlation between the severity of enteric neuron loss and gastrointestinal motility defects. This screen provides biological tools that serve as the basis for future mechanistic studies.  相似文献   
4.
OBJECTIVE: The purpose of this study was to determine the prevalence and spectrum of colonic wall changes in patients with cirrhosis and to determine the association between these colonic wall changes and portal hypertension. MATERIALS AND METHODS: Abdominal CT examinations of 57 patients with cirrhosis were evaluated for colonic abnormalities including bowel wall thickening and pneumatosis. The degree and extent of colonic involvement, other CT features of cirrhosis including ascites and portal hypertension, and clinical symptoms were recorded. A correlation was made with available colonoscopy, exploratory laparotomy, and pathologic results. RESULTS: Colonic wall abnormalities were seen in 37% (21/57) of the patients with cirrhosis, 25% (14/57) of whom had isolated or predominantly right-sided colonic changes. Abnormal bowel wall thickening (ranging from 6 mm to 3 cm in thickness) was present in 35% of the patients. Pneumatosis was found in 4% of the patients. Of the 18 liver transplant recipients who had CT examinations before and after liver transplantation, colonic changes were seen in 44% preoperatively but in only 6% postoperatively. Isolated right-sided colonic changes and diffuse colonic changes were associated with varices in 93% and 100% of the patients, respectively; with ascites in 93% and 100%, respectively; and with splenomegaly in 83% and 86%, respectively. Specific or focal bowel symptoms were present in only 29% of the patients with colonic changes, whether the changes were diffuse or isolated to the right side. CONCLUSION: Thirty-five percent of the patients with severe cirrhosis who underwent CT were shown to have colonic wall thickening; two thirds of these patients had thickening limited predominantly to the right colon. We postulated that predominantly right-sided colonic wall thickening may be related to changes in blood flow and hydrostatic pressures caused by portal hypertension. Many patients with isolated or predominately right-sided colonic wall thickening did not have specific or focal bowel symptoms, and in most patients, the colonic wall thickening resolved after successful liver transplantation, requiring no further testing. On the other hand, we found that pneumatosis or severe diffuse colonic wall thickening may indicate a more serious colonic problem such as ischemia or infection with Clostridium difficile and should prompt further investigation.  相似文献   
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In this article we discuss the importance of monitoring body temperature. Some effects of hypothermia are covered, along with the benefits of careful monitoring. Also discussed are the basic use and application of the most common monitoring methods, as well as the methods we used to help maintain body temperature.  相似文献   
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Borges L  Kubin M  Kuhlman T 《Blood》2003,101(4):1484-1486
LIRs are immunoglobulinlike receptors that have activating and inhibitory functions in leukocytes. Here we report the identification of the first LIR family member, LIR9, expressed as a membrane-bound receptor and as a secreted molecule. We identified 4 different forms of LIR9, 2 of which encode transmembrane molecules and 2 encode secreted molecules. The transmembrane forms of LIR9 contain a short cytoplasmic domain and a charged arginine residue within the transmembrane region that is likely to mediate its association with another coreceptor. LIR9 is mostly expressed in myeloid cells, including monocytes and neutrophils. Cross-linking of LIR9 on the surfaces of monocytes induces calcium flux and secretion of the proinflammatory cytokines interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), and IL-6, indicating that LIR9 could play a role in triggering innate immune responses.  相似文献   
10.
Moutafis M  Dalibon N  Liu N  Kuhlman G  Fischler M 《Anesthesia and analgesia》2002,94(4):830-4, table of contents
One-lung ventilation (OLV) induces an increase in pulmonary shunt sometimes associated with a decrease in PaO2 despite ventilation with 100% oxygen. PaO2 improvement has been reported in one-lung ventilated animals receiving IV almitrine, a pulmonary vasoconstrictor. We evaluated the ability of almitrine to prevent a decrease in PaO2 during OLV. Patients without pulmonary hypertension undergoing OLV for lung surgery were randomly assigned to receive either placebo (Group P, n = 8) or almitrine infusion at a rate of 8 microg x kg(-1) x min(-1) (Group A, n = 8) from the start of OLV. Gasometric and hemodynamic values were recorded with the patient in the lateral decubitus position during two-lung ventilation and at 10-min intervals during OLV over a 30-min period (OLV-10, OLV-20, OLV-30). Compared with the values found during two-lung ventilation (434 +/- 22 mm Hg in Group P and 426 +/- 23 mm Hg in Group A), PaO2 decreased at OLV-10 (305 +/- 46 mm Hg), OLV-20 (203 +/- 20 mm Hg), and OLV-30 (178 +/- 18 mm Hg) in Group P (P < 0.05) and at OLV-20 (354 +/- 25 mm Hg) and OLV-30 (325 +/- 17 mm Hg) in Group A (P < 0.05). PaO2 values differed between the groups at OLV-20 and OLV-30 (P < 0.05). Pulmonary artery pressure and cardiac output did not change. In conclusion, 8 microg x kg(-1) x min(-1) IV almitrine prevents and limits the OLV-induced decrease in PaO2 without causing any hemodynamic modification. IMPLICATIONS: Eight microg x kg(-1) x min(-1) IV almitrine limits one-lung ventilation-induced decrease in PaO2 without causing any hemodynamic modification in patients without pulmonary hypertension.  相似文献   
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