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991.
Obstructed partial anomalous pulmonary venous connections (APVC) are rare but may be associated with severe pulmonary hypertension (PHTN) and warrant urgent relief. There are a number of case reports of successful catheter intervention for obstructed total APVC. We present the first reported case of catheter intervention to relieve obstructed, left sided PAPVC in a neonate with Turner syndrome. © 2016 Wiley Periodicals, Inc.  相似文献   
992.
The inhibitory effect of duodenal acidification and intraduodenal fat infusion on pentagastrin-stimulated gastric secretion in normal subjects and in patients with duodenal ulcer was studied. Intraduodenal infusion of acid resulted in inhibition of HCl secretion found to be significant only in ulcer patients. Pepsin output, although lower during the first 15 minutes of duodenal acidification, later increased. Intraduodenal infusion of olive oil resulted in significant inhibition of HCl and pepsin output in both groups of patients, which was maximal 45–60 minutes after the beginning of fat infusion. Gastric secretion was more readily inhibited in ulcer patients than in normal subjects; this difference was particularly evident in inhibition of pepsin secretion. In addition, decrease in concentration of HCl and pepsin was observed to be significant only in ulcer patients. Mechanisms by which duodenal acidification and fat inhibit gastric secretion are discussed. The results obtained suggest that secretin, which is probably responsible for inhibition after duodenal acidification, is not the inhibitor during inhibition by fat. The ulcer patients were found to have unimpaired mechanisms of inhibition by acid and fat.  相似文献   
993.
We investigate adoption of the TRA in different age groups and study the relationship between age and access site related outcomes in a national cohort of patients undergoing PCI in the UK. Previous studies have reported conflicting data on radial access site adoption between different age groups, with age an independent predictor of failure of procedures undertaken through the radial approach. Age and access site related outcomes (based on transradial (TRA) and transfemoral (TFA) access) were studied in 469,983 PCI procedures undertaken in the UK from 2006 to 2012 in the age groups; <60, 60–<70, 70–<80, and ≥80 in the British Cardiovascular Intervention Society database. We studied access site practice in 469,983 patients who underwent PCI procedures in the United Kingdom. TRA utilization increased from 17.5% to 65.6% in the age group <60, and 16.6% to 54.5% in the age group ≥80 between 2006 and 2012. TRA was independently associated with decreased 30‐day mortality in all age groups (<60: OR 0.64; 95% CI 0.54–0.74, P < 0.0001; 60–<70: OR 0.65; 95% CI 0.57–75, P < 0.0001, 70–<80: OR 0.58 (0.52–0.65, P < 0.0001 and ≥80: OR 0.65 (0.57–0.73, P < 0.0001). Adoption of the TRA for PCI has occurred least in older patients in the UK despite similar associations between TRA use and decreased 30‐day mortality observed in all age groups. © 2015 Wiley Periodicals, Inc.  相似文献   
994.
995.
Bone marrow transplantation (BMT) is now an option for some patients with sickle cell disease (SCD). Many SCD patients are multiply transfused with red blood cells (RBCs), and may be immunized to alloantigens other than erythrocyte antigens. Because platelet refractoriness is a significant complication during BMT, we wished to determine the prevalence of alloimmunization to platelets in transfused SCD patients. Sera collected from 47 transfused and 14 untransfused SCD patients were screened for HLA and platelet-specific antibodies. Transfusion and RBC antibody histories were reviewed. A subset of the patients were rescreened 1 year later. Eighty-five percent of patients with at least 50 RBC transfusions (22 of 26), 48% of patients with less than 50 transfusions (10 of 21), and none of 14 untransfused patients demonstrated platelet alloimmunization (P < .05). Platelet alloimmunization was more prevalent than RBC alloimmunization (20% to 30%). Half of the platelet reactivity was chloroquine-elutable. Eighteen of 22 patients (82%) on chronic RBC transfusion remained platelet-alloimmunized 11 to 22 months after initial testing. In summary, 85% of heavily transfused SCD patients are alloimmunized to HLA and/or platelet-specific antigens. These patients may be refractory to platelet transfusion, a condition that would increase their risk during BMT. Leukodepletion in the transfusion support of SCD patients should be considered to prevent platelet alloimmunization.  相似文献   
996.
Animal dietary studies related to human colorectal carcinogenesis are usually based on AIN-76A diet, which is dissimilar to human food in source, preparation, and content. Our aim was to examine colonic epithelial proliferation in rats fed a diet based on the mean daily food intake of adenoma patients. Foods were prepared as reported by the adenoma patients and dehydrated; 64 Sprague-Dawley rats were fed either “human adenoma” or AIN-76A diet and every eight weeks, eight from each group were sacrificed. Both groups gained weight equally, had no colonic histological changes, but during the study showed progressive lengthening of colonic crypts (P<0.01) and decreased proliferation (P<0.05) in distal colons. Compared to controls, rats fed human adenoma diet had significantly longer crypts (P<0.01) and more labeled cells (P<0.05) at 32 weeks; overall they had increased proliferation (P<0.01), most significantly in the distal colon. Thus, food eaten by adenoma patients induced hyperproliferative changes in the rat colon during growth and maturity, especially the distal colon, as found in humans at risk for neoplasia.  相似文献   
997.
We designed and evaluated a program to teach internal medicine residents behavioral counseling skills for multiple risk factor modification. Integrating physician-patient communication, negotiation skills, and the transtheoretical model of behavior change, we used small group discussion and standardized patients. The 18 participating residents increased their ability to modify patient behavior during videotaped interviews, mean pretest/posttest score: 33.1/40.1 (Student’s pairedt test, p<.0001). Physician self-efficacy in screening for risk factors and effecting behavioral change in patients was increased (p<.0001), as were positive attitudes toward psychosocial factors (p<.003). Our teaching effectively increased the residents’ self-efficacy and performance of behavioral counseling.  相似文献   
998.
Interleukin-6 (IL-6), a product of bone marrow stromal cells (BMSCs), is a growth factor for multiple myeloma (MM) cells. Transforming growth factor-beta1 (TGF-beta1) is also produced by BMSCs and can regulate IL- 6 secretion by several tissues, including BMSCs. The present study was designed to characterize in vitro tumor growth regulation by TGF-beta1 in MM. Sorted CD38+CD45RA- MM cells secreted significantly more TGF- beta1 (8.2 +/- 2.0 ng/mL) than peripheral blood mononuclear cells (P < .001), splenic B cells (P < .001), and CD40 ligand (CD40L) pretreated B cells (P < .05). TGF-beta1 secretion by MM-BMMCs (3.8 +/- 0.9 ng/mL) was significantly greater than by N-BMMCs (1.2 +/- 0.1 ng/mL, P < .001). MM-BMSCs also secreted significantly more TGF-beta1 (6.6 +/- 2.5 ng/mL, n = 11) than N-BMSCs (4.4 +/- 0.6 ng/mL, P < .02, n = 10) and N- BMSC lines (3.9 +/- 0.2 ng/mL, P < .02, n = 6). TGF-beta1 secretion was correlated with IL-6 secretion in MM-BMSCs. Anti-TGF-beta1 monoclonal antibody both blocked IL-6 secretion by BMSCs and inhibited the increments in IL-6 secretion by BMSCs induced by MM cell adhesion. Moreover, exogenous TGF-beta1 upregulated IL-6 secretion by MM-BMSCs, normal BMSCs, and CD38+ CD45RA- MM cells, as well as tumor cell proliferation. This is in contrast to the inhibitory effect of TGF- beta1 on proliferation and Ig secretion of normal splenic B cells. Finally, retinoblastoma proteins (pRB) are constitutively phosphorylated in MM cells; TGF-beta1 either did not alter or increased pRB phosphorylation. pRB are dephosphorylated in splenic B cells and phosphorylated in CD40L triggered B cells in contrast to its effects on MM cells, TGF-beta1 decreased phosphorylation of pRB in CD40L treated B cells. These results suggest that TGF-beta1 is produced in MM by both tumor cells and BMSCs, with related tumore cell growth. Moreover, MM cell growth may be enhanced by resistance of tumor cells to the inhibitory effects of TGF-beta1 on normal B-cell proliferation and Ig secretion.  相似文献   
999.
The authors developed quantitative radioimmunoassays to allow direct measurement of total human IgG and individual IgG subclasses among antibodies bound to cell surfaces. The assays use four mouse monoclonal radioiodinated antibodies, one that reacts equally well with all four human IgG subclasses and three that are specific for human IgG subclasses 1, 2, or 3. The assays were used to analyze IgG subclass composition in 21 high-titer anti-D samples from Rh-negative volunteers immunized for Rh immunoglobulin production. Anti-D activity was restricted primarily to the IgG1 and IgG3 subclasses. Eleven of 21 sera demonstrated red cell antibodies with a marked predominance of IgG1 (87 +/- 3.6% of total IgG antibody, +/- SEM) and low levels of IgG3 (1.4 +/- 0.73%). In the remaining 10 sera, IgG3 made up a greater proportion of total IgG antibody (32 +/- 3.8%), although IgG1 was still predominant (61 +/- 4.1%). This observed dichotomy in the IgG subclass profiles of different anti-D sera may be a consideration in the selection of anti-D sera for the production of the immunoglobulin used in the prophylaxis of Rh-incompatible pregnancies.  相似文献   
1000.
Sumatriptan blocks spreading depression in isolated chick retina   总被引:1,自引:0,他引:1  
Spreading depression is a neurohumoral phenomenon that has been related to the pathophysiology of migraine. The recently introduced 5HT1D agonist anti-migraine compound sumatriptan blocks neurogenic extravasation and induces cerebral vasoconstriction, but the actual mechanism of action against migraine remains obscure. Retinal spreading depression (RSD) velocity has been measured in isolated chick retinas in the presence of 0.05-2.00:nM sumatriptan. This drug reversibly blocks RSD in a concentration-dependent manner. Since the preparation is blood-vessel free, this effect must be related to the nervous tissue.  相似文献   
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