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991.
BACKGROUND & AIMS: The aim of this study was to compare the diagnostic yield of capsule endoscopy (CE) with double-balloon enteroscopy (DBE) in small-bowel (SB) disease using meta-analysis. METHODS: We performed a search of studies comparing CE with DBE in SB disease. Data on diagnostic yield of CE and DBE were extracted, pooled, and analyzed. The weighted incremental yield (IY(W)) (yield of CE--yield of DBE) of CE over DBE and 95% confidence intervals (95% CIs) for pooled data were calculated using a fixed-effect model (FEM) for analyses without, and a random-effect model (REM) for analyses with, significant heterogeneity. RESULTS: Eleven studies compared CE and DBE; the pooled overall yield for CE and DBE was 60% (n = 397) and 57% (n = 360), respectively (IY(W), 3%; 95% CI, -4% to 10%; P = .42; FEM). Ten studies reported vascular findings; the pooled yield for CE and DBE was 24% (n = 371) and 24% (n = 364), respectively (IY(W), 0%; 95% CI, -5% to 6%; P = .88; REM). Nine studies reported inflammatory findings; the pooled yield for CE and DBE was 18% (n = 343) and 16% (n = 336), respectively (IY(W), 0%; 95% CI, -5% to 6%; P = .89; FEM). Nine studies reported polyps/tumors; the pooled yield for CE and DBE was 11% (n = 343) and 11% (n = 336), respectively (IY(W), -1%; 95% CI, -5% to 4%; P = .76; FEM). CONCLUSIONS: CE and DBE have comparable diagnostic yield in SB disease, including obscure gastrointestinal bleeding. CE should be the initial diagnostic test because of its noninvasive quality, tolerance, ability to view the entire SB, and for determining the initial route of DBE. Because of its therapeutic capabilities, DBE may be indicated in patients with a positive finding on CE requiring a biopsy or therapeutic intervention, if suspicion for a SB lesion is high despite a negative CE, and in patients with active bleeding.  相似文献   
992.
Preservation of hematopoietic stem and progenitor cell survival is required for recovery from radiation-induced myelosuppression. We recently showed that short-term injection of antiapoptotic cytokine combinations into mice soon after lethal gamma irradiation promoted survival. The present study investigated the hematopoietic response of cynomolgus monkeys to a single dose of stem cell factor, FLT-3 ligand, megakaryocyte growth and development factor, and interleukin-3 in combination (4F, each factor given intravenously at 50 microg/kg) administered 2 hours after 5-Gy gamma irradiation. Treated monkeys (n = 4) experienced no thrombocytopenia. Only 1 in 4 displayed a transient period of neutropenia (neutrophil [ANC] count < 0.5 x 10(9)/L), whereas all irradiated controls (n = 4) experienced neutropenia (5-12 days) and thrombocytopenia (platelet [PLT] count < 20 x 10(9)/L, 5-31 days). Treated animals exhibited an impressive 2-wave PLT response that peaked at days 8 and 22 after total body irradiation (TBI). Areas under the curve (AUC) of PLTs, ANCs, white blood cells (WBCs), and red blood cells (RBCs) between days 0 and 90 were significantly higher in treated animals than in controls. Humeral bone marrow-derived clonogenic activity was significantly spared at 24 hours and 4 days after TBI in treated monkeys. No apparent impairment of the hematopoietic status and stem cell pool, in terms of long-term culture-initiating cells (LTC-ICs) and side population (SP) cells, was observed after 15 months. These results strongly suggest that the 4F cytokine combination, as a single dose regimen, could act as an emergency treatment for nuclear accident or terrorism victims.  相似文献   
993.
Behcet's disease and pregnancy relationship study   总被引:1,自引:0,他引:1  
The effects of pregnancy on the course of Behcet's disease (BD), and vice versa, are unknown and little has been reported. We have studied three groups of women: (1) group A included 61 pregnancies in 23 women with BD, 25 pregnancies took place in 10 patients already diagnosed (group 1A) and 36 pregnancies occurred in 13 patients before disease diagnosis (group 2A); (2) group B included 30 females with 83 pregnancies affected by recurrent oral ulcers (ROU); (3) group C included 20 healthy women with 61 pregnancies. We investigated the effects of BD on pregnancy and fetal outcome, and the influence of gestation on the course of BD. A questionnaire was used in which specific information about each pregnancy, labour and puerperium was collected. We looked for medical confirmation in all cases where any pathology had been identified. No significant differences were found in the incidence of pregnancy complications between groups. The incidence of perinatal death was also similar and neither congenital abnormalities nor neonatal BD were observed. Only two patients observed a flare of the disease and in two cases the diagnosis of BD was made during the pregnancy. In our series, the outcome of pregnancy was generally good in BD patients, disease manifestations were not consistently worsened and fetal outcome was excellent. The first case of Budd-Chiari syndrome during the puerperium in a BD patient is reported.   相似文献   
994.
Background & Aims: Phenylimidazothiazoles have recently been shown to activate wild-type and mutant cystic fibrosis transmembrane conductance regulator (CFTR) Cl channels in transfected cells and were proposed as therapy for cystic fibrosis. The aim of this study was to investigate the effects of phenylimidazothiazoles on regulated transepithelial Cl transport in intact epithelia. Methods: T84 intestinal epithelial cells grown on permeable supports and stripped human colonic mucosal sheets were studied by conventional current-voltage clamping. Selective permeabilization of apical or basolateral membranes with the monovalent ionophore nystatin was used to isolate basolateral K+ and apical Cl channel activity, respectively. 86Rb+ uptake was assessed for Na/K/2Cl cotransporter and Na+,K+–adenosine triphosphatase activity. Results: In T84 monolayers and human colon, levamisole and its brominated derivative bromotetramisole failed to activate transepithelial secretion. In fact, these compounds dose-dependently inhibited secretory responses to the cyclic adenosine monophosphate agonist forskolin and the Ca2+ agonist carbachol. In permeabilized T84 monolayers, phenylimidazothiazoles weakly activated apical Cl currents (consistent with their reported action on CFTR) and did not affect bumetanide-sensitive or bumetanide-insensitive 86Rb+ uptake. Instead, they profoundly inhibited the basolateral Ba2+-sensitive and Ba2+-insensitive K+ currents. Conclusions: Phenylimidazothiazoles block K+ channels required for Cl-secretory responses elicited by diverse pathways in model epithelia and native colon, an effect that outweighs their ability to activate apical Cl channels.GASTROENTEROLOGY 1998;114:1257-1267  相似文献   
995.
The effect of interleukin-4 (IL-4) on the fibrinolytic system of human microvascular and macrovascular endothelial cells in culture was studied. Only foreskin microvascular endothelial cells (EC) responded to IL-4 treatment with a dose- and time-dependent increase in urokinase- type plasminogen activator (u-PA) (control: 3.0 +/- 0.8 ng/10(5) cells/24 h; 200 U/mL IL-4: 6.7 +/- 0.8 ng/10(5) cells/24 h), whereas human macrovascular EC remained unaffected. A maximum effect was achieved with 200 U/mL IL-4. Little u-PA activity was detected in the conditioned media of human foreskin microvascular EC (HFMEC) treated without and with IL-4 before plasmin treatment (control: 0.03 +/- 0.003 IU/10(5) cells/20 h; 200 U/mL IL-4: 0.09 +/- 0.007 IU/10(5) cells/20 h). These values increased to 0.18 +/- 0.02 IU/10(5) cells/20 h and 0.53 +/- 0.04 IU/10(5) cells/20 h, respectively, after plasmin treatment, indicating that u-PA is released by HFMEC predominantly in its inactive precursor form single-chain u-PA (scu-PA). u-PA activity increased also in the cell lysates of HFMEC up to 2.5-fold after IL-4 treatment. Plasminogen activator inhibitor type-1 (PAI-1) levels produced by HFMEC remained unaffected by IL-4, whereas tissue-type plasminogen activator (t-PA) levels were slightly decreased when HFMEC were treated with IL-4. These findings were also reflected in the specific mRNA levels as determined by Northern blotting. u-PA-specific mRNA increased significantly in HFMEC in the presence of IL-4, whereas t-PA mRNA and PAI-1-specific mRNA in HFMEC and u-PA specific mRNA in human saphenous vein EC (HSVEC) remained unaffected by IL-4 treatment. Our findings suggest a role for IL-4 in the process of angiogenesis, in addition to its known proliferative effect on human microvascular EC, by increasing the fibrinolytic potential of such EC, thereby facilitating extracellular proteolysis and cell migration.  相似文献   
996.
The role of HLA-DPB1 disparity in the development of acute graft-versus- host disease (GVHD) following unrelated donor (URD) marrow transplantation is unknown. We studied 129 patients who underwent marrow transplantation from HLA-A, -B, -DRB, and -DQB matched URDs to determine whether matching for HLA-DPB1 alleles significantly decreased the risk of developing acute GVHD. HLA-DPB1 alleles were determined by sequence-specific oligonucleotide hybridization and by the number of patient DPB1 alleles not shared by the donor scored. The Kaplan-Meier probability of developing grades II to IV acute GVHD was determined for patients incompatible for zero (group A), one (group B), or two (group C) DPB1 alleles. Of the 129 pairs, there was no recipient DPB1 incompatibility in 28 (22%), one DPB1 mismatch in 72 (56%), and two DPB1 mismatches in 29 (22%). The probability of grades II to IV acute GVHD was 0.69 (0.50, 0.86) for group A, 0.83 (0.73, 0.91) for group B, and 0.72 (0.56, 0.87) for group C (P = .63). These results indicate that matching patients and unrelated donors for HLA-A, -B, -DRB, and - DQB does not predict for matching at DPB1. However, recipient incompatibility for DPB1 alleles does not detectably influence the risk of acute GVHD. Therefore, HLA-DP disparity should not be used as an exclusion criterion for donor selection in unrelated marrow transplantation.  相似文献   
997.
Haga  P; Cotes  PM; Till  JA; Minty  BD; Shinebourne  EA 《Blood》1987,70(3):822-826
Serum immunoreactive erythropoietin (siEp) was measured in 27 cyanotic and 21 acyanotic children with congenital heart disease, age 4 months to 10 years. The geometric mean value was 9 mIU/mL for each group with 95% range from 3 to 26 mIU/mL and 4 to 22 mIU/mL for the cyanotic and acyanotic subjects, respectively. The levels are similar to those found in normal adults using the same assay system. Three cyanotic subjects showed increased siEp values. One was anemic relative to his hypoxemia, and the other two showed signs of increasing hypoxia. There was a significant negative correlation between siEp and arterial oxygen content. However, siEp did not correlate significantly with hemoglobin, hematocrit, PaO2, or SaO2. Despite normal siEp levels, the cyanotic children showed compensatory erythropoiesis with significantly elevated hemoglobin and hematocrit levels, which did correlate inversely with PaO2 and SaO2. Arterial oxygen content was also significantly higher in the cyanotic subjects (p less than 0.02). The cyanotic children seemed to display the same pattern as observed in man and animals exposed to prolonged hypobaric hypoxia, where after an initial rise in erythropoietin values the levels fall to normal, while increased erythropoiesis is sustained.  相似文献   
998.
Cytogenetic studies were performed on direct and 24-hour culture preparations of eight lymph node biopsies from seven patients with acquired immunodeficiency syndrome (AIDS) or AIDS-related complex (ARC)- associated lymphadenopathy in whom histological evidence of lymphoma was not detected. Three of these seven had chromosomal abnormalities, including chromosome instability in one and clonal chromosomal abnormalities in two; one of the latter was a t(8;14)(q24;q32). The remaining five showed normal karyotypes. Epstein-Barr virus (EBV) titers were elevated in all three patients that exhibited chromosome abnormalities, two of whom later developed malignant lymphoma. A control group of five patients with reactive lymphadenopathy not associated with AIDS failed to reveal chromosomal aberrations, but elevated EBV titers were present in two. These data are consistent with current views on the role of EBV and chromosome change in the development of lymphoma in immunodeficient states and suggest that karyotypically abnormal AIDS-related lymphadenopathy represents a prelymphomatous proliferation.  相似文献   
999.
The pharmacokinetics of a single oral dose of buspirone (20 mg) were determined in 12 patients with cirrhosis and 12 normal subjects. The mean AUC of buspirone was 55 +/- 38 s.d. ng ml-1 h in cirrhotics and 3.5 +/- 2.4 s.d. ng ml-1 h in normals. The time until maximum concentration (tmax) attained was similar in the two groups (0.6 vs 0.7 h), but mean maximum concentration Cmax was higher in patients (18.8 +/- 16.3 s.d. ng ml-1) than in normals (1.2 +/- 0.8 s.d. ng ml-1). Mean elimination half-life of buspirone was greater in cirrhotics, but this difference was marginally significant statistically (cirrhotics, 6.1 +/- 3.5 s.d. h, normals 3.2 +/- 1.5 s.d. h, P = 0.05). Eight of 12 patients and seven of 12 normal subjects had a second peak in the plasma concentrations of buspirone. In patients this occurred at 10.8 +/- 7.4 s.d. h after the dose, and its mean concentration was 3.1 +/- 6.6 ng ml-1. In normal subjects the second peak occurred at 4.3 +/- 2.1 h after the dose and its mean concentration was 0.5 +/- 0.3 ng ml-1. On the kinetic evidence buspirone should be used with caution in liver disease.  相似文献   
1000.

Background  

Frailty is highly prevalent in older people. Its serious adverse consequences, such as disability, are considered to be a public health problem. Therefore, disability prevention in community-dwelling frail older people is considered to be a priority for research and clinical practice in geriatric care. With regard to disability prevention, valid screening instruments are needed to identify frail older people in time. The aim of this study was to evaluate and compare the psychometric properties of three screening instruments: the Groningen Frailty Indicator (GFI), the Tilburg Frailty Indicator (TFI) and the Sherbrooke Postal Questionnaire (SPQ). For validation purposes the Groningen Activity Restriction Scale (GARS) was added.  相似文献   
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