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151.
Little is known about differences in practice patterns or outcomes in the management of patients who have atrial fibrillation in Canada compared with those in the United States (US). We evaluated the effect that the country of enrollment may have on the management patterns and clinical outcomes in patients who participated in the AFFIRM study. Three thousand four hundred patients came from the US and 660 from Canada. In the US, patients were more likely to have a history of coronary artery disease (39% vs 35%, p = 0.03), hypertension (72% vs 67%, p = 0.01), or congestive heart failure (24% vs 18%, p = 0.0002). More US participants were <65 years of age (25% vs 19%, p = 0.003). Although at randomization the use of warfarin was comparable, during follow-up Canadians were more likely to be treated with warfarin and to be therapeutically anticoagulated. Mortality rate at 5 years was higher in US patients (24% vs 16%, p = 0.001), and the composite end point (death, disabling stroke, major bleeding, cardiac arrest, or anoxic encephalopathy) was also higher in US patients (30% vs 22%, p = 0.0005). Even after adjusting for known differences in baseline characteristics, the risk of death was lower in Canada (hazard ratio 0.70, p = 0.02). In conclusion, in the AFFIRM study, US subjects were more likely to have preexisting cardiovascular diseases despite being younger (<65 years old) than those in Canada. Effective warfarin therapy was more commonly employed in Canada. After correcting for the known differences in baseline characteristics, Canadian patients who had atrial fibrillation had a lower mortality risk.  相似文献   
152.
In the present study, we show by adhesion assays and ultrastructural studies that platelets can bind to CD34+ cells from human blood and bone marrow and that this interaction interferes with the accurate detection of endogenously expressed platelet glycoproteins (GPs). The interaction between these cells was found to be reversible, dependent on divalent cations, and mediated by P-selectin. Enzymatic characterization showed the involvement of sialic acid residues, protein(s). The demonstration of mRNA for the P-selectin glycoprotein ligand 1 (PSGL-1) in the CD34+ cells by polymerase chain reaction (PCR) analysis suggests that this molecule is present in these cells. Under conditions that prevent platelet adhesion, a small but distinct subpopulation of CD34+ cells diffusely expressed the platelet GPIIb/IIIa complex. These cells were visualized by immunochemical studies. Furthermore, synthesis of mRNA for GPIIb and GPIIIa by CD34+ cells was shown using PCR analysis. The semiquantitative PCR results show relatively higher amounts of GPIIb mRNA than of PF4 mRNA in CD34+CD41+ cells in comparison with this ratio in platelets. This finding is a strong indication that the PCR results are not caused by contaminating adhering platelets. MoAbs against GPIa GPIb alpha, GPV, P- selectin, and the alpha-chain of the vitronectin receptor did not react with CD34+ cells. The number of CD34+ cells expressing GPIIb/IIIa present in peripheral blood stem cell (PBSC) transplants was determined and was correlated with platelet recovery after intensive chemotherapy in 27 patients. The number of CD34+CD41+ cells correlated significantly better with the time of platelet recovery after PBSC transplantation (r = .83, P = .04) than did the total number of CD34+ cells (r = .55). Statistical analysis produced a threshold value for rapid platelet recovery of 0.34 x 10(6) CD34+CD41+ cells/kg. This study suggests that if performed in the presence of EDTA the flow cytometric measurement of GPIIb/IIIa on CD34+ cells provides the most accurate indication of the platelet reconstitutive capacity of the PBSC transplant.  相似文献   
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The implications of lighted ureteral stenting in laparoscopic colectomy.   总被引:1,自引:0,他引:1  
OBJECTIVE: The placement of indwelling ureteral catheters during colorectal surgery has been recommended for prevention of ureteral injuries. With the advent of laparoscopic colectomy (LCo), the role of preoperative placement of lighted ureteral stents (LUS) has also become commonplace. We sought to evaluate the value of lighted ureteral stent placement in laparoscopic colectomy. METHODS: Sixty-six patients underwent LCo with LUS inserted preoperatively. Stents were removed in the immediate postoperative period. Two surgeons performed all the colectomies; 32 patients were males and 34 were females. Fifty patients underwent sigmoid colectomy, 4 had abdominoperineal resection, 4 had right colectomy, and 1 each had transverse or subtotal colectomy. Eighteen patients had a diagnosis of cancer, 34 had diverticular disease, and 14 had neoplastic polyps. Forty patients had bilateral and 26 had unilateral stent placement. A review of the incidence of ureteral injuries, hematuria, and anuria as the cause of acute renal failure was accomplished, comparing the unilateral and bilateral stented groups. RESULTS: One (1.5%) patient suffered a left ureteral laceration during sigmoid colectomy. This was managed successfully with stent reinsertion. Sixty-five (98.4%) patients had gross hematuria lasting 2.93 days (1 to 6 days). The cost of bilateral stent placement was $1,504.32. A statistically significant difference occurred in the duration of hematuria (days) between patients who had unilateral (2.5 +/- 0.82) and bilateral stent placement (3.37 +/- 1.05), (P < 0.001). Four patients suffered from anuria, 2 required renal support needing hemodialysis for 3 to 6 days, 3 (75%) had bilateral stents, and 1 (25%) had a unilateral stent. CONCLUSIONS: We recommend the placement of lighted ureteral stents as a valuable adjunct to laparoscopic colectomy to safeguard ureteral integrity. Transient hematuria is common but requires no intervention. Reflux anuria occurs infrequently and is reversible.  相似文献   
157.
This study aimed to determine the effect of hamstring botulinum toxin A (Btx-A) injection in 10 children with crouch gait in terms of changes in muscle length and lower-limb kinematics. Before Btx-A injection limb kinematics were recorded. Maximum hamstring lengths and excursions were calculated by computer modelling of the lower limb. Data were compared with the averaged hamstring lengths of 10 control children. Hamstrings were denned as short if their length was shorter than the average maximum length minus one standard deviation. Gait analysis was repeated 2 weeks after isolated hamstring Btx-A injection. Pre- and postinjection kinematic data and muscle lengths were then compared. Four of 18 injected limbs in three subjects had short medial hamstring before injection, none of the subjects had short lateral hamstrings. Muscle excursion was significantly reduced in the short and adequate maximum muscle length groups. A significant increase in the semimembranosus and semitendinosus length in all of the injected limbs was noted. Only in the short muscle group was a significant increase in muscle excursion observed. Knee extension improved by 13° in the adequate muscle length group and by 15.6° in the short muscle length group. Pelvic tilt and hip flexion increased in both groups non-significantly. Average walking speed postinjection increased from 0.60 ms-1 to 0.71 ms-1. Short hamstrings are over-diagnosed in crouch gait. Hamstring Btx-A injection in patients with crouch gait produces significant, repeatable muscle lengthening and improved ambulatory function.  相似文献   
158.
Cognitive therapy is now widely recommended for the treatment of schizophrenia. However, little is known about factors predicting good outcome. We are describing separate sub-analyses of two randomized controlled trials of Cognitive Behaviour Therapy for schizophrenia. In one trial expert therapists provided therapy while in the second trial brief therapy was provided by trained nurses. In both trials psychopathology was assessed using the Comprehensive Psychopathological Rating Scale (CPRS) and the Health of the Nation Outcome Scale (HoNOS). Insight, delusions, hallucinations and negative and positive symptoms were also measured. In brief therapy trial higher levels of insight and high CPRS global impression score predicted good outcome in the CBT group. Analyses using similar variables did not reveal any specific predictors for good outcome in the second trial.  相似文献   
159.
Previous biochemical and histochemical studies have failed to clarify the nature or quantity of gangliosides in CNS astrocytes. Using improved methodologies for bulk isolation of both neurons and astrocytes as well as for ganglioside purification, we find significantly higher ganglioside concentration in astrocytes and very similar thin-layer chromatography (TLC) patterns for the two cell types. However, in vivo labeling of glycoconjugates via intracerebral injection of [3H]glucosamine prior to cell isolation revealed a different picture: whereas glycoproteins were well-labeled in both cell types after labeling periods of 1-2 h, gangliosides were appreciably labeled only in neurons. With longer time periods (8-48 h) between injection and sacrifice, there was convergence of specific radioactivity of gangliosides from the two isolated cell preparations. These changes are compared to those observed in synaptosomes and microsomes that were isolated simultaneously. The results suggest limited ganglioside synthetic ability in astrocytes as compared to neurons, a conclusion supported by assay of UDP-galNAc:GM3 N-acetylgalactosaminyltransferase in the isolated cells. Nevertheless, the presence of ganglioside GM1 in a substantial portion of bulk-isolated astrocytes was demonstrated by indirect immunofluorescent detection of cholera toxin binding. Ideas on the reconciliation of these apparently contradictory phenomena, including the possibility of intercellular transfer and/or phagocytosis are discussed.  相似文献   
160.
A case of regenerated splenosis 20 years after splenectomy masquerading as a gastric fundic mass is reported. Several endoscopic examinations revealed an extramucosal extrinsic mass in the gastric fundus and a chain of small ulcers high along (he lesser curvature. Radionuclide technetium scan and CT scan accurately detected the regenerated splenic tissue indenting the gastric fundus and thus obviated the need for angiography and exploratory surgery.  相似文献   
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