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81.
Summary We report a patient with agnogenic myeloid metaplasia associated with debilitating bone pain due to increased bone turnover and osteosclerosis. Treatment with etidronate at a dose of 6 mg/kg per day on alternate months resulted in a complete recovery of bone symptoms and normalization of metabolic parameters of bone turnover; unexpectedly, a sustained haematological improvement was also observed after several months of therapy, suggesting that bone marrow microenvironment improvement was able to restore a nearly normal haemopoiesis. We suggest that diphosphonate therapy may be of value in patients with AMM and increased bone turnover.  相似文献   
82.
PURPOSE: This retrospective study assesses the results of total colectomy and ileorectostomy for inflammatory bowel disease. METHODS: Between January 1974 and December 1990, 90 patients underwent total colectomy and ileorectal anastomosis for chronic ulcerative colitis (n=48) or Crohn's colitis (n=42) at the Mayo Clinic. Patients' records were reviewed retrospectively. Long-term results were assessed by chart reviews and postal questionnaires. Conversion to a permanent ileostomy, with or without proctectomy, was considered a failure of the procedure. The Kaplan-Meier method was used to estimate survivorship free of failure. The log-rank test was used to compare survivorship curves. Ninety-five percent confidence intervals were calculated at selected time points.P values<0.05 were considered to be statistically significant. RESULTS: The main indication for surgery was refractory chronic disease. There were no immediate postoperative deaths. The anastomotic leakage rate was 4.4 percent, and small-bowel obstruction occurred in 15.6 percent. At the time of follow-up (mean, 6.5±4.8 years), 46 patients (58.9 percent) had recurrence or exacerbation of the disease. This was the most common indication for subsequent proctectomy/permanent ileostomy in the follow-up period. There were 8 failures in 48 patients with ulcerative colitis (16.7 percent) and 11 failures in 42 patients with Crohn's disease (26.2 percent), although this difference was not statistically significant. Cumulative probability of having a functioning ileorectal anastomosis at five years was 84.2 percent (95 percent confidence interval, 71–95.9 percent) for ulcerative colitis and 73.8 percent (95 percent confidence interval, 58.6–88.6 percent) for Crohn's disease. In the latter group, females showed a significantly lower cumulative probability of having a functioning ileorectal anastomosis (females, 634 percent; males, 92.3 percent;P =0.04). Crohn's patients 36 years of age or younger also showed a lower probability of success (patients 36 years, 57 percent; patients >36 years, 93.8 percent;P =0.03). In the group with chronic ulcerative colitis, younger patients also seemed to require additional surgery more frequently; however, this difference was not statistically significant. Previous duration of symptoms, with mild or moderate disease in a distensible rectum, had no effect on results in either disease group. Functional results were acceptable in 63.6 and 87.5 percent of patients with Crohn's and ulcerative colitis, respectively. Eighty-four percent of ulcerative colitis patients and 91 percent of Crohn's disease patients reported an improvement in their quality of life, and overall, more than 90 percent considered their health status to be better than before surgery. One patient with ulcerative colitis developed carcinoma of the rectal stump 11.5 years after the colectomy and ileorectal anastomosis (cumulative probability of remaining free of cancer, 85.7 percent at 12 years; 95 percent confidence interval, 57.7–100 percent). CONCLUSIONS: These results demonstrate that, in selected patients with a relatively spared rectum and without severe perineal disease, total colectomy and ileorectal anastomosis still remains a viable option to total proctocolectomy with extensive Crohn's colitis. In addition, ileorectal anastomosis, as a sphincter-saving procedure, continues to have a place in the surgical treatment of chronic ulcerative colitis for high-risk or older patients who are not good candidates for ileal pouch-anal anastomosis, when the latter procedure cannot be done because of technical reasons and in the presence of advanced carcinoma concomitant with colitis, when life expectancy is limited.  相似文献   
83.
84.
ObjectiveTo assess the effectiveness of a multimedia informed consent tool for adults participating in a clinical trial in the Gambia.MethodsAdults eligible for inclusion in a malaria treatment trial (n = 311) were randomized to receive information needed for informed consent using either a multimedia tool (intervention arm) or a standard procedure (control arm). A computerized, audio questionnaire was used to assess participants’ comprehension of informed consent. This was done immediately after consent had been obtained (at day 0) and at subsequent follow-up visits (days 7, 14, 21 and 28). The acceptability and ease of use of the multimedia tool were assessed in focus groups.FindingsOn day 0, the median comprehension score in the intervention arm was 64% compared with 40% in the control arm (P = 0.042). The difference remained significant at all follow-up visits. Poorer comprehension was independently associated with female sex (odds ratio, OR: 0.29; 95% confidence interval, CI: 0.12–0.70) and residing in Jahaly rather than Basse province (OR: 0.33; 95% CI: 0.13–0.82). There was no significant independent association with educational level. The risk that a participant’s comprehension score would drop to half of the initial value was lower in the intervention arm (hazard ratio 0.22, 95% CI: 0.16–0.31). Overall, 70% (42/60) of focus group participants from the intervention arm found the multimedia tool clear and easy to understand.ConclusionA multimedia informed consent tool significantly improved comprehension and retention of consent information by research participants with low levels of literacy.  相似文献   
85.
86.
Implantation of cardiac resynchronization therapy (CRT) devices can be challenging, time consuming, and associated with high‐dose x‐ray exposure. We present the technique in which an electromagnetic navigation system (MediGuideTM, St. Jude Medical) and an electroanatomical three‐dimensional mapping system (EnSite NavX, St Jude Medical) are usefully combined for implanting implantable cardioverter defibrillator CRT devices with strong reduction of x‐ray exposure, and for targeting the most delayed regions in the activation maps avoiding scars for optimal CRT response.  相似文献   
87.

Background

There is increasing evidence that childhood vaccines have effects that extend beyond their target disease. The objective of this study was to assess the effects of routine childhood vaccines on bacterial carriage in the nasopharynx.

Methods

A cohort of children from rural Gambia was recruited at birth and followed up for one year. Nasopharyngeal swabs were taken immediately after birth, every two weeks for the first six months and then every other month. The presence of bacteria in the nasopharynx (Haemophilus influenzae, Streptococcus pneumoniae, Staphylococcus aureus) was compared before and after the administration of DTP-Hib-HepB and measles-yellow fever vaccines.

Results

A total of 1,779 nasopharyngeal swabs were collected from 136 children for whom vaccination data were available. The prevalence of bacterial carriage was high: 82.2% S. pneumoniae, 30.6%, S.aureus, 27.8% H. influenzae. Carriage of H. influenzae (OR = 0.36; 95% CI: 0.13, 0.99) and S. pneumoniae (OR = 0.25; 95% CI: 0.07, 0.90) were significantly reduced after measles-yellow fever vaccination; while DTP-Hib-HepB had no effect on bacterial carriage.

Conclusions

Nasopharyngeal bacterial carriage is unaffected by DTP-Hib-HepB vaccination and reduced after measles-yellow fever vaccination.  相似文献   
88.
A fast, precise, noninvasive, high-throughput, and simple approach for detecting malaria in humans and mosquitoes is not possible with current techniques that depend on blood sampling, reagents, facilities, tedious procedures, and trained personnel. We designed a device for rapid (20-second) noninvasive diagnosis of Plasmodium falciparum infection in a malaria patient without drawing blood or using any reagent. This method uses transdermal optical excitation and acoustic detection of vapor nanobubbles around intraparasite hemozoin. The same device also identified individual malaria parasite–infected Anopheles mosquitoes in a few seconds and can be realized as a low-cost universal tool for clinical and field diagnoses.  相似文献   
89.
90.
The objective of this study was to evaluate the safety and efficacy of low-intensity warfarin treatment plus aspirin during the first 6 months after surgery in patients undergoing heart valve substitution with mechanical prostheses. Vitamin K antagonists (VKA) are able to reduce but not eliminate thrombosis and systemic embolism in patients with mechanical heart valves. The intensity of treatment and additional use of aspirin in these patients is still controversial. Consecutive patients undergoing aortic or mitral valve replacement (or a combination of the two) with mechanical prostheses were invited to participate in the study. After stratifying for site of prosthesis, patients were randomized to receive low intensity VKA treatment (target INR 2.5) plus aspirin (100 mg/day) for the first six months (Group A) or standard-intensity (INR target 3.7) VKA treatment (Group B). Mean follow-up was 1.5 years. Principal outcome events were systemic embolism, major bleeding, and vascular death. A total of 94 patients in Group A and 104 in Group B were randomized and followed up for 144 and 163 patient years, respectively. There were 5 (5%) events in Group A (4 major bleeding events and 1 vascular death) and 4 (4%) in group B (2 major bleeding events and 2 ischemic stroke). All the events except 1 occurred within the first 6 months after surgery. Cumulative incidence of primary outcome events was 5.8% (95% CI 0.9 to 10.7) in Group A and 4.3% (95% CI 0.2 to 8.4) in Group B (p=0.6). Low-intensity treatment plus aspirin during the first six months after surgery appears to be as effective and safe as moderate-high-intensity anticoagulation.  相似文献   
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