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51.
我非常高兴向大家推荐这份发展中国家幽门螺杆菌(H.priori)临床指南。该指南的编译是由数位在该领域具有丰富临床经验的世界知名专家共同完成的。  相似文献   
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The present study was performed to examine the hypothesis that autoregulation-related changes in renal vascular resistance (RVR) are mediated by extracellular ATP. By use of a microdialysis method, renal interstitial concentrations of ATP and adenosine were measured at different renal arterial pressures (RAPs) within the autoregulatory range in anesthetized dogs (n=12). RAP was reduced in steps from the ambient pressure (131+/-4 mm Hg) to 105+/-3 mm Hg (step 1) and 80+/-2 mm Hg (step 2). Renal blood flow and glomerular filtration rate exhibited efficient autoregulation in response to these changes in RAP. RVR decreased by 22+/-2% in step 1 (P<0.01) and 38+/-3% in step 2 (P<0.01). The control renal interstitial concentration of ATP was 6.51+/-0.71 nmol/L and decreased to 4. 51+/-0.55 nmol/L in step 1 (P<0.01) and 2.77+/-0.47 nmol/L in step 2 (P<0.01). In contrast, the adenosine concentrations (117+/-6 nmol/L) were not altered significantly. Changes in ATP levels were highly correlated with changes in RVR (r=0.88, P<0.0001). Further studies demonstrated that stimulation of the tubuloglomerular feedback (TGF) mechanism by increasing distal volume delivery elicited with acetazolamide also led to increases in renal interstitial ATP concentrations, whereas furosemide, which is known to block TGF responses, reduced renal interstitial fluid ATP concentrations. The data demonstrate a positive relation between renal interstitial fluid ATP concentrations and both autoregulation- and TGF-dependent changes in RVR and thus support the hypothesis that changes in extracellular ATP contribute to the RVR adjustments responsible for the mechanism of renal autoregulation.  相似文献   
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Abstrakt Vergibt ein behandelnder Arzt eine Laboruntersuchung an einen externen Laborarzt, kommt entweder direkt ein Vertragsverh?ltnis zwischen dem Laborarzt und dem Patienten zustande oder der Patient haftet dem Laborarzt aus den Grunds?tzen der Gesch?ftsführung ohne Auftrag.  相似文献   
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The presence of inhalation injury has been reported to increase fluid requirements for resuscitation from burn shock after thermal injury. To evaluate the effect of inhalation injury on the magnitude of burn-induced shock, the characteristics of resuscitation of 171 patients with burns covering at least 25 percent of the total body surface area were reviewed. When inhalation injury was suspected, confirmation by xenon-133 scanning, bronchoscopy, or both was obtained. Initial fluid resuscitation was calculated according to the Parkland formula, and titration was initiated to maintain a urine output of 30 to 50 ml/hour. Fifty-one patients had inhalation injuries. Patients with inhalation injuries had a mean fluid requirement of 5.76 ml/kg per percentage of total body surface area burned and a mean sodium requirement of 0.94 mEq/kg per percentage of total body surface area burned to achieve successful resuscitation, compared with a fluid requirement of 3.98 ml/kg per percentage of total body surface area burned and a sodium requirement of 0.68 mEq/kg per percentage of total body surface area burned for the group without inhalation injury (p less than 0.05). These data confirm and quantitate that inhalation injury accompanying thermal trauma increases the magnitude of total body injury and requires increased volumes of fluid and sodium to achieve resuscitation from early burn shock.  相似文献   
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Control of vaccine-preventable diseases depends on maintaininghigh levels of immunization coverage. Immunization coverageamong preschool children remains suboptimal in some areas andsociodemographic subgroups, as well as for more recently introducedvaccines, leaving susceptible young children vulnerable to complicationsfrom vaccine-preventable diseases. This paper reviews approacheshistorically used to measure immunization coverage among preschoolchildren in the United States. The strengths and weaknessesof various approaches to measuring immunization coverage amongpreschool children are explored, with emphasis on the currentmeans to measure national immunization coverage—the NationalImmunization Survey. Methods for measuring immunization coverageamong preschool children at local and state levels are alsoevaluated. Future opportunities and challenges for measuringimmunization coverage at the local, state, and national levelsare explored. child health services • child, preschool • communicable disease control • comparative study • immunization programs • immunization schedule • vaccination  相似文献   
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A prospective comparative trial of allogeneic versus autologous bone marrow transplant (BMT) was conducted. Sixty-six consecutive patients (median age, 41; range, 15 to 60; female:male ratio = 21:45) entered this clinical trial. Priority for allogeneic BMT was given to patients who were 55 or younger and had a major histocompatibility complex- matched or 1-antigen-disparate sibling donor. Autologous BMT was offered to all other patients whose age was 60 or younger. Patients who had no sibling donor and who had BM involvement at the time of evaluation were not eligible. Thirty-one patients received an allograft, and 35 patients received an autograft. Thirteen patients received a BM graft purged with 4-hydroperoxycyclophosphamide because of previous BM involvement. Patients who had previous radiation to the thoracic and/or abdominal areas of more than 20 Gy received a preparative regimen consisting of cyclophosphamide (1,800 mg/m2/d for 4 days), VP-16 (200 mg/m2 every 12 hours for 8 doses), and 1,3-bis(2- chloroethyl)-1-nitrosourea (600 mg/m2 as 1 dose). Other patients received cyclophosphamide 1,800 mg/m2/d for 4 days followed by total body irradiation of 12 Gy administered as a single daily fraction over 4 days. With a median follow-up of 14 months, the progression-free survival (PFS) for autograft and allograft recipients was 24% +/- 8% (+/- SE) and 47% +/- 9%, respectively, (P = .21). However, the probability of disease progression was significantly higher in the autologous group (69% +/- 9%) than in the allogeneic group (20% +/- 10%; P = .001). When other confounding prognostic factors were adjusted in the multivariate analysis, chemosensitive disease and allograft were found to have a significant favorable influence on probability of disease progression (P = .03 and .003), but only chemosensitive disease had a significant influence on the PFS (P < .002). Our results suggest the existence of graft-versus-lymphoma effect and also support the rationale of using immunotherapy after autologous BMT. Allogeneic BMT should be preferable to autologous BMT in younger patients with lymphoma.  相似文献   
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