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31.
32.
Limiting the widespread use of 24-hr pH monitoring is the necessity of manometrically placing the pH probe 5 cm above the proximal lower esophageal sphincter (LES) border. Therefore, we prospectively compared LES localization by gastroesophageal pH step-up with manometry in 71 patients and 14 asymptomatic volunteers. The gastroesophageal pH step-up significantly correlated with the proximal LES border in patients (r=0.53, P<0.0001) and volunteers (r=0.91, P<0.0001). Based on previously published criteria, the pH step-up value was considered acceptably accurate if it was within ±3 cm (6 cm total span) of the manometrically determined proximal LES border. In 58% of patients and 29% of volunteers the pH step-up occurred outside this accuracy range. Esophagitis (P=0.015) and abnormal reflux parameters (P=0.002) were variables contributing to this error. Subsequent analysis found that the pH step-up overestimated the proximal LES border and occurred at the midportion of the sphincter. The pH step-up still inaccurately located the mid LES in 34% of patients. Therefore, manometry should remain the standard for accurate LES localization prior to placing the pH probe.  相似文献   
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In 20 healthy volunteers ingesting 5 to 50 ml of51Cr-red cells, reaction intensities obtained with four chemical methods for fecal occult blood were compared with the “true” blood loss simultaneously determined by radioassay of each stool. Dilute tincture of guaiac reagent was found to have the same sensitivity and high frequency of false-positive reactions as the saturated guaiac reagent, but was more reproducible. HematestTM was slightly less sensitive but was poorly reproducible and yielded frequent false-negative as well as false-positive reactions. False-positive reactions by both methods were not eliminated by a meat-free diet; they were increased with guaiac reagents if stools were stored for 3 or more days. A new guaiac method (HemoccultTM) was found to be one-fourth as sensitive as the older tests, but was virtually free from false-positive reactions, even on an unrestricted diet and after storage of the stool specimens. It is recommended that the use of Hematest be abandoned and that Hemoccult be used preferentially if future studies confirm that its sensitivity is sufficient to detect most gastrointestinal lesions which are yielding occult blood.  相似文献   
35.
Voso MT  Scardocci A  Guidi F  Zini G  Di Mario A  Pagano L  Hohaus S  Leone G 《Blood》2004,103(2):698-700
Death-associated protein kinase (DAP-kinase), a proapoptotic serine/threonine kinase, is a candidate tumor suppressor gene. We studied the methylation status of DAP-kinase of 194 bone marrow samples from 160 patients with acute myeloid leukemia (AML) and 34 with a myelodysplastic syndrome (MDS) at the time of initial diagnosis by polymerase chain reaction (PCR). Hypermethylation of DAP-kinase was present in 27.5% (44 of 160) of AML and in 47% (16 of 34) of MDS specimens and significantly correlated to loss of DAP-kinase expression (P =.008). It was significantly more frequent in AML secondary to therapy for other malignancies (s-AML; 14 of 29, 48.3%), as compared to de novo AML (30 of 131, 22.9%, P =.01). DAP-kinase hypermethylation in AML was associated with myelodysplastic changes in the bone marrow at the time of the initial diagnosis (P =.002) and with the presence of cytogenetic abnormalities (P =.02). Alteration in the apoptotic response due to the loss of DAP-kinase function may be an early event in the transformation pathway to secondary leukemia via myelodysplasia.  相似文献   
36.

Aim

The aim of the present study was to determine (1) whether successful intraoperative electromyography monitoring for lateral spread response (LSR) is possible with partial neuromuscular blockade (NMB) in subjects undergoing microvascular decompression (MVD) for hemifacial spasm and (2) the adequate level of NMB to achieve that goal.

Material and methods

A total of 61 patients in whom LSR was monitored during MVD were enrolled in the study. Patients were randomly allocated to two groups: group TOF in which the NMB target was maintenance of two train-of-four (TOF) counts and group T1 in which the NMB target was maintenance of a T1/Tc ratio of 50?% (T1: first twitch height of TOF and Tc: control twitch height). The adductor pollicis brevis muscle was used to monitor TOF responses. The frequency of successful LSR monitoring, defined as successful baseline establishment and maintenance of LSR until surgical decompression, was compared between the two groups.

Results

Of the 61 patients 2 were excluded from the study so that 30 patients in group TOF and 29 patients in group T1 were analyzed. The success rate of LSR monitoring was clinically acceptable and significantly higher in group T1 than in group TOF, i.e. n?=?15 (50.0?%) in group TOF versus n?=?24 (82.8?%) in group T1 (P?=?0.008), corresponding to a 32.8?% higher success rate in group T1 than group TOF (95?% CI: 13.9–51.7?%). Mean vecuronium infusion dose was smaller and mean TOF count was higher in group T1 than group TOF with a TOF count =?2 (1) in group TOF versus 3 (1) in group T1 (P?=?0.003). Mean sevoflurane and remifentanil infusion doses were not different between groups. There was no incidence of spontaneous movement during microscopy in either group.

Conclusion

Maintenance of partial NMB with a target T1/Tc ratio of 50?% resulted in a clinically acceptable success rate of LSR monitoring and surgical condition during MVD. Maintenance of partial NMB with a target T1/Tc ratio of 50?% rather than TOF count of two during LSR monitoring for MVD can therefore be recommended.  相似文献   
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38.
Myelodysplastic syndromes (MDS) are common in elderly patients. Recombinant human erythro-poietin (rHuEPO) has been widely used to treat anemia in lower risk MDS patients, but few data are known about rHuEPO treatment in the very elderly patient group. In order to investigate the role of rHuEPO treatment in terms of response, overall survival (OS), and toxicity in a very elderly MDS patient group, 93 MDS patients treated with rHuEPO when aged ≥80 years were selected among MDS cases enrolled in a retrospective multicenter study by the cooperative group Gruppo Romano Mielodisplasie (GROM) from Jan 2002 to Dec 2010. At baseline, median age was 82.7 (range 80–99.1) with a median hemoglobin (Hb) level of 9 g/dl (range 6–10.8). The initial dose of rHuEPO was standard (epoetin alpha 40,000 IU/week or epoetin beta 30,000 IU/week) in 59 (63.4 %) pa-tients or high in 34 (36.6 %) (epoetin alpha 80,000 IU/week) patients. We observed an erythroid response (ER) in 59 (63.4 %) patients. No thrombotic event was reported. Independent predictive factors for ER were low transfusion requirement before treatment (p?=?0.004), ferritin <200 ng/ml (p?=?0.017), Hb >8 g/dl (p?=?0.034), and a high-dose rHuEPO treatment (p?=?0.032). Median OS from rHuEPO start was 49.3 months (95 % CI 27.5–68.4) in responders versus 30.6 months (95 % CI 7.3–53.8) in resistant patients (p?=?0.185). In conclusion, rHuEPO treatment is safe and effective also in the very elderly MDS patients. However, further larger studies are warranted to evaluate if EPO treatment could be worthwhile in terms of quality of life and cost-efficacy in very old patients.  相似文献   
39.
Strenuous exercise promotes changes in salivary IgA and can be associated with a high incidence of upper respiratory tract Infections. However, moderate exercise enhances immune function. The effect of exercise on salivary IgA has been well studied, but its effect on other immunological parameters is poorly studied. Thus, this study determined the effect of moderate acute exercise on immunological salivary parameters, such as the levels of cytokines (TGF‐β and IL‐5), IgA, α‐amylase and total protein, over 24 h. Ten male adult subjects exercised for 60 min at an intensity of 70% VO2 peak. Saliva samples were collected before (‘basal’) and 0, 12 and 24 h after an exercise session. The total salivary protein was lower after 12 and 24 h than immediately after exercise, whereas α‐amylase increased at 12 and 24 h after exercise compared with basal levels. The IgA concentration was increased at 24 h after exercise relative to immediately after exercise, and there was no difference in the IL‐5 while TGF‐β concentration increased in recovery. In conclusion, 70% VO2 peak exercise does not induce changes immediately after exercise, but after 24 h, it produces an increase in salivary TGF‐β without changing IL‐5.  相似文献   
40.
The JCAH move to evaluate clinical outcomes as part of its ongoing accreditation process has significant implications for infection control, APIC, and research. Through a concerted, progressive plan to address this issue, APIC can be a pathfinder in helping to prepare its members for this change. A proactive approach to both continued input into the process and the initiation of research to establish the groundwork are clearly indicated.  相似文献   
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