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261.
BackgroundDifferences in excess weight loss, body mass index (BMI) change, and body composition have been related to different types of bariatric procedures. Our objective was to explore these alterations related to body mass in superobese (SO) and morbidly obese (MO) patients in a university hospital setting.MethodsPatients provided written informed consent and had their body composition measured before and after surgery using bioimpedance (Tanita 310). The t test was used to compare MO and SO. Pearson's correlations were used to examine the BMI, excessive BMI loss, percentage of body fat (BF) change, and fat-free mass.ResultsA total of 133 MO patients had a BMI of 43.3 kg/m2 and 88 SO patients had a BMI of 59.4 kg/m2. The percentage of BF was 46.7% and 51.9% (P < .0001). The differences in the follow-up period after surgery (21.5 and 20.6 months; P = .62) and patient age (43.4 and 42.5 yr) were not significant, but the gender distribution was significant (P = .003). After surgery, the MO patients had a BMI of 30.9 ± 5.7 kg/m2 and the SO patients had a BMI of 37.3 ± 9.0 kg/m2. The percentage of BF was not different between the 2 groups (MO, 33.1% ± 9.6% and SO, 35.0% ± 12.4%; P = .21). Gender differences in the percentage of BF were present before surgery; however, after surgery, these were absent for the men in the 2 groups (24.8% and 26.6%; P = .51). The change in the BMI and the change in the BF had a stronger correlation for the MO patients (r = .83 versus r = .53) than for the SO patients. The fat-free mass loss correlated with the change in BMI without regard to procedure. The percentage of excessive BMI loss was 65.1% for the MO and 63.4% for the SO patients (P = .64).ConclusionsThe SO patients achieved excessive BMI loss similar to that of the MO patients, with more SO men choosing biliopancreatic diversion/duodenal switch. At a BMI of 37.3 kg/m2, the SO patients had a percentage of BF that was not different from that of the MO patients at 30.9 kg/m2. The fat-free mass losses correlated with the change in BMI.  相似文献   
262.
BACKGROUND: The use of antithrombotic agents and falls are independently associated with an increased risk of hemorrhagic injury. However, few studies have delineated the risk of fall-related hemorrhagic complications in persons who are taking antithrombotic therapy. The objective of this study was to compare the rates of fall-related hemorrhagic injury in hospital in-patients who are taking and not taking antithrombotic therapy. METHODS: A 4-year retrospective chart review of consecutive patients who fell during admission to a 500-bed tertiary-care teaching hospital was conducted. Major hemorrhagic injuries including subdural hematomas and major bleeding/cuts, patients' use of antithrombotic medication (warfarin, aspirin, clopidogrel and heparin) and their anticoagulation status at the time of their fall were recorded. RESULTS: A total of 2635 falls in 1861 patients were reviewed. Approximately 10% of falls caused major hemorrhagic injury. One fall resulted in a subdural hematoma. Persons taking warfarin were less likely to suffer a fall-related major hemorrhagic injury compared with persons not taking antithrombotic therapy (warfarin, 6%; no therapy, 11%; p = 0.01). Logistic regression showed that fall-related major hemorrhagic injury was associated with female gender (odds ratio 1.6; 95% CI 1.3, 2.1), use of aspirin (odds ratio 1.4; 95% CI 1.1, 1.8) and use of clopidogrel (odds ratio 2.2; 95% CI 1.1, 4.8), but not with the use of warfarin or heparin, or the intensity of anticoagulation. CONCLUSIONS: In this study, compared with persons taking no antithrombotic therapy, those taking warfarin had lower rates of fall-related hemorrhagic injuries. The absolute rate of the development of fall-related intracranial hemorrhagic injury such as subdural hematomas was low, even in persons taking warfarin. These counter-intuitive results may be due to selection bias, and suggest that physicians are very conservative in selecting patients for warfarin therapy, choosing only those who are sufficiently healthy to be at much lower than average risk of suffering fall-related hemorrhagic injuries. This phenomenon may lead to physicians overestimating the potential for fall-related major hemorrhagic injury in persons taking antithrombotic therapy, with the possible denial of warfarin therapy to many of those who would benefit. This perception may contribute to the care gap between the number of patients who would theoretically derive overall benefit from warfarin therapy and those who are actually receiving it.  相似文献   
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Ninety-nine patients with acute nonlymphocytic leukemia (ANLL) received HLA-identical bone marrow transplants (BMTs) from sibling donors after preparation with high doses of busulfan and cyclophosphamide. Forty- nine patients were transplanted in first complete remission (CR), and 50 patients were transplanted in second and third CR and early relapse. Fifty-three received one of three regimens containing primarily low- dose cyclophosphamide (group I) for graft-v-host disease (GVHD) prophylaxis; since March 1983, 46 patients received intravenous (IV) cyclosporine (group II). After December 1983, only cytomegalovirus (CMV)-seronegative blood products were used in appropriate patients, and since April 1984 patients seropositive for herpes-simplex virus (HSV) and CMV received high-dose acyclovir prophylaxis. For patients transplanted in first CR, there was a significantly lower incidence of acute GVHD (P = .005) and deaths related to GVHD and interstitial pneumonitis (P = .001) in patients in group II. This was reflected in an improved Kaplan-Meier probability of disease-free survival (DFS) in the 22 patients transplanted in group II as compared with the 27 patients in group I (64% +/- 10% v 30% +/- 9%, P = .017). The probability of remaining in remission was slightly lower in group II (82% +/- 9% v 94% +/- 6%, P = .479). For patients transplanted in second and third CR and early relapse, the incidence of acute GVHD (P = .026) and deaths related to GVHD and interstitial pneumonitis was significantly lower in group II (P = .029); the probability of remaining in remission was also less (47% +/- 15% v 91% +/- 15%, P = .022). However, the probability of DFS was not significantly different between the two groups (26% +/- 10% v 35% +/- 18%, P = .957). We conclude that transplantation for patients in first CR who received IV cyclosporine therapy is effective treatment; patients with more refractory disease treated with the same cyclosporine regimen (group II) had a lower incidence of GVHD than those treated in group I, but survival did not improve because of an increase in the number of relapses and other nonleukemic complications.  相似文献   
265.
The human interleukin-3 receptor (IL-3R) is expressed on myeloid, lymphoid, and vascular endothelial cells, where it transduces IL-3- dependent signals leading to cell activation. Although IL-3R activation may play a role in hematopoiesis and immunity, its aberrant expression or excessive stimulation may contribute to pathologic conditions such as leukemia, lymphoma, and allergic reactions. We describe here the generation and characterization of a monoclonal antibody (MoAb), 7G3, which specifically binds to the IL-3R alpha-chain and completely abolishes its function. MoAb 7G3 immunoprecipitated and recognized in Western blots the IL-3R alpha-chain expressed by transfected cells and bound to primary cells expressing IL-3R alpha. MoAb 7G3 bound the IL-3R alpha-chain with a kd of 900 pmol/L and inhibited 125I-IL-3 binding to high- and low-affinity receptors in a dose-dependent manner. Conversely, IL-3 but not granulocyte-macrophage colony-stimulating factor (GM-CSF) inhibited 125I-7G3 binding to high- and low-affinity IL- 3Rs, indicating that MoAb 7G3 and IL-3 bind to common or adjacent sites. In keeping with the inhibition of IL-3 binding, MoAb 7G3 antagonized IL-3 biologic activities, namely stimulation of TF-1 cell proliferation, basophil histamine release, and IL-6 and IL-8 secretion from human endothelial cells. Two other anti-IL-3R alpha-chain MoAbs failed to inhibit IL-3 binding or function. Epitope mapping experiments using truncated IL-3R alpha-chain mutants and IL-3R alpha/GM-CSFR alpha chimeras revealed that 31 amino acids in the N-terminus of IL-3R alpha were required for MoAb 7G3 binding. MoAb 7G3 may be of clinical significance for antagonizing IL-3 in pathologic conditions such as some myeloid leukemias, follicular B-cell lymphoma, and allergy. Furthermore, these results implicate the N-terminal domain of IL-3R alpha in IL-3 binding. Since this domain is unique to the IL-3/GM- CSF/IL-5 receptor subfamily, it may represent a novel and common binding feature in these receptors.  相似文献   
266.
BackgroundStudies have shown that type 2 diabetes (T2DM) improves or resolves shortly after Roux-en-Y gastric bypass (RYGB). Few data are available on T2DM recurrence or the effect of weight regain on T2DM status.MethodsA review of 42 RYGB patients with T2DM and ≥3 years of follow-up and laboratory data was performed. Postoperative weight loss and T2DM status was assessed. Recurrence or worsening was defined as hemoglobin A1c >6.0% and fasting glucose >124 mg/dL and/or medication required after remission or improvement. Patients whose T2DM recurred or worsened were compared with those whose did not, and patients whose T2DM improved were compared with those whose T2DM resolved.ResultsT2DM had either resolved or improved in all patients (64% and 36%, respectively); 24% (10) recurred or worsened. The patients with recurrence or worsening had had a lower preoperative body mass index than those without recurrence or worsening (47.9 versus 52.9 kg/m2; P = .05), regained a greater percentage of their lost weight (37.7% versus 15.4%; P = .002), had a greater weight loss failure rate (63% versus 14%; P = .03), and had greater postoperative glucose levels (138 versus 102 mg/dL; P = .0002). Patients who required insulin or oral medication before RYGB were more likely to experience improvement rather than resolution (92% versus 8%, P ≤.0001; and 85% versus 15%; P = .0006, respectively).ConclusionOur results have shown that beyond 3 years after RYGB, the incidence of T2DM recurrence or worsening in patients with initial resolution or improvement was significant. In our patients, a greater likelihood of recurrence or worsening of T2DM was associated with a lower preoperative body mass index. Before widespread acceptance of bariatric surgery as a definitive treatment for those with T2DM can be achieved, additional study of this recurrence phenomenon is indicated.  相似文献   
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Magnetic resonance (MR) imaging of the thyroid was performed with a 1.5-T system and local receiver coil in 19 "healthy" subjects and 34 patients with various focal and diffuse thyroid disorders. The normal gland was typically homogeneous with increased intensity relative to that of muscle on images obtained with long repetition times (TRs) and long echo times (TEs). Adjacent structures in the neck and upper mediastinum were well displayed. Thyroid nodules as small as 4-5 mm were identified. Follicular adenomas appeared as well-circumscribed nodules of heterogeneous intensity, increasing significantly in signal with long TRs/TEs. Colloid cysts and hemorrhagic cysts had homogeneous high signal with both short and long TRs/TEs. Two of three carcinomas were seen as poorly marginated lesions with associated cervical lymphadenopathy clearly depicted as increased intensity with long TRs/TEs. A follicular adenoma containing microscopic papillary carcinoma appeared similar to other benign adenomatoid nodules. A functioning nodule was isointense with normal gland at all pulse sequences. Characteristic patterns of diffuse abnormality were observed in cases of multinodular goiter, Hashimoto thyroiditis, and Graves disease, although additional cases are required to determine specificity. High-field-strength surface-coil MR imaging appears to be a sensitive method for identifying gross morphology of focal, multinodular, and diffuse disorders of the thyroid and involvement of surrounding structures in the neck.  相似文献   
269.

Introduction

The aim of this study was to determine whether the current management of common iliac artery aneurysms (CIAAs) by vascular surgeons is in tune with existing guidelines for referral.

Methods

This was a postal survey of members of the Vascular Society of Great Britain and Ireland. The main outcome measures were relative frequency of ruptured CIAA, respondents’ size threshold for surveillance versus intervention, and their management strategies for isolated unilateral CIAAs, bilateral CIAAs and aortoiliac aneurysms.

Results

Two hundred and eighty-four (anonymous) replies were received (48% response rate). Respondents estimated that a ruptured abdominal aortic aneurysm (AAA) was 25 times more common than a ruptured CIAA. Most surgeons (64%) would wait until a CIAA reached 4cm in diameter before considering intervention. This threshold was not affected by other scenarios such as the presence of a bilateral CIAA or a small (4cm) AAA. Eighty per cent of surgeons would treat a non-ruptured CIAA by stenting, where possible. The majority of surgeons felt that ultrasonography surveillance should be commenced when a CIAA exceeds 1.5cm, with a surveillance interval of 1 year but with more frequent surveillance for CIAAs wider than 3cm.

Conclusions

Existing guidelines that recommend referral for possible intervention for non-ruptured CIAAs at a diameter of 3cm are out of tune with current practice. Most surgeons in this survey would wait until the diameter was 4cm.  相似文献   
270.
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