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431.
During wedge hepatic venography, mechanical injection should be accomplished at the lowest possible rate in order to avoid hemorrhagic infarction. Small amounts of contrast material should be administered. Hepatic angiography may result in an area of tumor blush at the site of a previous wedge injection.  相似文献   
432.
Carbon dioxide was used either alone or in combination with standard triiodinated contrast media in 32 patients who underwent percutaneous nephrostomy. Carbon dioxide was used to opacify the posterior calyces, which are the uppermost structures in the kidney of the prone or prone-oblique patient. Carbon dioxide is usually injected in small amounts (20-40 cm3), although clinical and laboratory data indicate that it can be used as the only medium in large amounts with complete safety. There were no complications.  相似文献   
433.
尹述凡  毛文仁 《药学学报》1990,25(5):340-344
本文设计,并以反式-4-氨甲基环己基田酸和4-氨甲基苯甲酸为原料合成了11种新标题化合物,并经元素分析、红外光谱、核磁共振氢谱和质谱证实。初步抑酶活性测定表明,对腊样芽胞杆菌产生的β-内酰胺酶均有不同程度的抑制作用。  相似文献   
434.
Free fatty acid receptor 2 (FFAR2, also named GPR43), is activated by short‐chain fatty acids (SCFAs), such as butyrate, that are produced when gut bacteria ferment dietary fiber. FFAR2 has been suggested to regulate colonic inflammation, which is a major risk factor for the development of colon cancer and is also linked to epigenetic dysregulation in colon carcinogenesis. The current study assessed whether FFAR2, acting as an epigenetic regulator, protects against colon carcinogenesis. To mimic the mild inflammation that promotes human colon cancer, we treated mice with dextran sodium sulfate (DSS) overnight, which avoids excessive inflammation but induces mild inflammation that promotes colon carcinogenesis in the ApcMin/+ and the azoxymethane (AOM)‐treated mice. Our results showed that FFAR2 deficiency promotes the development of colon adenoma in the ApcMin/+/DSS mice and the progression of adenoma to adenocarcinoma in the AOM/DSS mice. FFAR2's downstream cAMP–PKA–CREB pathway was enhanced, leading to overexpression of histone deacetylases (HDACs) in the FFAR2‐deficient mice. ChIP‐qPCR analysis revealed differential binding of H3K27me3 and H3K4me3 histone marks onto the promoter regions of inflammation suppressors (e.g., sfrp1, dkk3, socs1), resulting in decreased expression of these genes in the FFAR2‐deficient mice. Also, more neutrophils infiltrated into tumors and colon lamina propria of the FFAR2‐deficient mice. Depletion of neutrophils blocked the progression of colon tumors. In addition, FFAR2 is required for butyrate to suppress HDAC expression and hypermethylation of inflammation suppressors. Therefore, our results suggest that FFAR2 is an epigenetic tumor suppressor that acts at multiple stages of colon carcinogenesis.  相似文献   
435.
Allogeneic hematopoietic cell transplantation (allo-HCT) is a high-risk treatment option for patients with hematologic malignancies. Advanced age and obesity can impact outcomes after allo-HCT. Previous registry studies of all age groups found that obesity does not affect outcomes. However, obesity can accelerate age-related decline in physical function and exacerbate comorbid conditions in older patients. Studies evaluating the effect of obesity on elderly patients undergoing allo-HCT are lacking. We performed a retrospective analysis of 86 nonobese (body mass index [BMI] <30) and obese (BMI ≥30) patients age ≥60 years who underwent allo-HCT for myeloid malignancies between January 2010 and June 2015. We found no significant between-group differences in mean age, sex, comorbid conditions, cytogenetic risk, disease indication for transplantation, or donor type. The median overall survival (OS) was 36 months for the BMI <30 group and 24 months for the BMI ≥30 group (P?=?.55). The median progression-free survival (PFS) was 10.1 months in the BMI <30 group and 13.6 months in the BMI ≥30 group (P?=?.93). There were no significant between-group differences in acute graft-versus-host disease (GVHD) and cumulative incidence of chronic GVHD at 1 year post-transplantation. Among patients admitted for transplantation, the mean length of stay was 25 days in the BMI <30 group and 26 days in the BMI ≥30 group (P?=?.64). The rate of readmission within 30 days of discharge was significantly higher in the BMI ≥30 group (34% versus 16%; P?=?.045). Our data reveal that in these elderly patients with myeloid malignancies undergoing allo-HCT, clinical outcomes, including OS, PFS, and GVHD, were not affected by obesity. Thus, in elderly patients, obesity should not preclude consideration for curative allo-HCT and does not portend worse outcomes after allo-HCT.  相似文献   
436.
Corticosteroid-refractory graft-versus-host disease (SR-GVHD) remains a significant source of morbidity after allogeneic hematopoietic cell transplantation. No standard therapy exists in this setting; however, recent studies have demonstrated a very promising role for ruxolitinib, an oral Janus kinase 1/2 inhibitor. With increasing evidence of efficacy for SR-GVHD, limited data exist describing complications of ruxolitinib use, specifically infectious complications during use in SR-GVHD. In this study we report outcomes and infectious complications at our institution with ruxolitinib use. Overall, 43 patients were treated with ruxolitinib for SR-GVHD, 19 for acute SR-GVHD and 24 for chronic SR-GVHD. With respect to acute SR-GVHD, 15 patients had grade III acute GVHD and 4 patients had grade IV acute GVHD. At 28 days, a response rate of 84% was detected. With respect to chronic SR-GVHD, 16 patients had moderate refractory disease and 8 had severe refractory disease. At around 28 days, a 63% response rate was detected. Overall, 42% of patients (n = 18) treated with ruxolitinib had a documented infectious event. Infectious events were significantly more common among patients treated for acute SR-GVHD (P < .005). Among patients treated for acute SR-GVHD, both viral (n = 11) and bacterial (n = 10) events were frequently encountered. Cytomegalovirus reactivation was detected in 4 patients without organ involvement in any patient. Bacteremia was the most common bacterial event (n = 8), and 2 patients died after development of bacteremia. Only 5 of 24 patients treated with ruxolitinib for chronic SR-GVHD developed infectious complications after initiation of therapy. Nearly an even number of viral (n = 3) and bacterial (n = 4) were detected. This study supports the use of ruxolitinib in SR-GVHD, with impressive responses observed in both acute and chronic SR-GVHD. Infectious complications were particularly frequent among patients treated for acute SR-GVHD, and nearly all these patients were concurrently on high-dose steroids while on ruxolitinib. This study suggests careful monitoring for viral reactivation is required for patients initiated on ruxolitinib, supports the role of continuing prophylactic antimicrobial measures in ruxolitinib-treated GVHD patients, and raises the question of whether bacterial prophylaxis should be considered among patients initiated on ruxolitinib for acute SR-GVHD, particularly while on high-dose steroids.  相似文献   
437.
BACKGROUND: Previous clinical trials have shown that the use of recombinant human erythropoietin (EPO) can facilitate autologous blood donation and reduce allogeneic blood transfusions in autologous blood donors who are anemic at first donation. However, the role of EPO therapy in nonanemic patients remains undefined. To identify this role, a randomized, controlled, multicenter dose-escalation trial was conducted in patients whose initial hematocrit was > 39 percent (0.39). STUDY DESIGN AND METHODS: EPO (150, 300, or 600 units/kg) or placebo was administered intravenously at each of six phlebotomy visits over a 3-week study period. Sixteen (14%) of 116 patients were unable to complete the treatment protocol because of adverse events (n = 11) or for personal reasons (n = 5); 2 patients (1 EPO and 1 placebo) experienced serious adverse events. RESULTS: In 91 evaluable patients, additional red cell production during the study period was 440 +/− 176, 621 +/− 215, 644 +/− 196, and 856 +/− 206 mL (mean +/− SD), respectively, for patients receiving placebo and EPO at 150, 300, and 600 units/kg (p < 0.05 for all EPO groups compared to placebo). However, the percentages of patients in each group who received allogeneic blood did not differ: 2 (9%) of 23 placebo patients and 6 (9%) of 68 EPO patients. CONCLUSION: It is concluded that, while EPO therapy increased preoperative red cell production, no clinical benefit could be demonstrated in autologous blood donors who were not anemic at first blood donation.  相似文献   
438.

Background:

Joint preservation is usually attempted in cases of bone tumors, though insufficient bone following tumour resection may prevent fixation of conventional joint sparing prosthesis. To preserve the hip joint in skeletally immature patients, we have combined autologous proximal femoral irradiation and intercalary re-implantation with custom made distal femoral replacements.

Materials and Methods:

A retrospective cohort study of four patients (aged 4-12 years); in whom irradiated autologous bone was combined with an extendable distal femoral endoprostheses was performed. There were three cases of osteosarcoma and one case of Ewing’s sarcoma.

Results:

At a mean follow-up of 70.5 months (range 26-185 months), all four patients were alive without evidence of local recurrence. There was no evidence of metastatic disease in three patients while one patient showed chest metastatic disease at presentation. In all cases, the irradiated segment of bone united with the proximal femur and demonstrated bone ongrowth at the prosthetic collar. There were no cases of loosening or peri-prosthetic fracture. One implant was revised after 14 years following fracture of the extending component of the endoprosthesis.

Conclusions:

We report encouraging results utilizing irradiated autologous proximal femoral bone combined with distal femoral replacement in skeletally immature patients.  相似文献   
439.
To evaluate the applicability of high-dose conditioning, CD34 selection, and enhanced natural killer (NK) cell?alloreactivity reported as promising after haploidentical transplantation, we tested the same strategy for patients with advanced/high-risk myeloid leukemia lacking either related or well-matched unrelated donors (URD). In a prospective multicenter clinical trial using pretransplantation conditioning of thiotepa (5 mg/kg/day × 2), fludarabine (40 mg/mg/M(2)/day × 5), and total body radiation (800 cGy) plus thymoglobulin (2.5 mg/kg/day × 2), as well as a CD34 selected filgrastim stimulated peripheral blood graft from a partial matched URD, we treated 24 patients. The patients (median age 40 [range: 22-61]) were mismatched at 1-3 of 10 HLA loci with their donors; all were mismatched at HLA-C. Thirty-seven percent were ethnic or racial minorities. Twenty-one of 24 engrafted promptly with 1 primary graft failure and 2 early deaths. The cumulative incidence of grade II-IV acute graft-versus-host disease (aGVHD) (34%, 95% confidence interval [CI], 14-54%), chronic GVHD (20%, 95% CI, 2%-38%), and relapse (26%, 95% CI, 8%-84%) were unaffected by KIR ligand donor:recipient mismatch (n = 5) versus KIR ligand match (n = 19). Only 3 (12%) had grade III-IV GVHD. Nonrelapse occurred in 17% (95% CI, 30%-31%) by 100 days and in 35% (95% CI, 15%-55%) by 1 year. Two-year survival and leukemia-free survival were each 40% (95% CI, 21%-59%) and was similar in KIR ligand matched or mismatched patients. Infections, mostly in the first 2 months, were frequent, and were the cause of death in 5?patients (35% of deaths). T cell recovery and NK cell proliferation and functional maturation were not altered by KIR ligand match or mismatch status. For these high-risk patients, this high intensity regimen and T depleted approach yielded satisfactory outcomes, but logistical difficulties in arranging URD grafts for patients with high-risk, unstable leukemia limited accrual. Improvements in peritransplantation disease control and additional measures to augment the allogeneic graft-versus-leukemia effect are still required.  相似文献   
440.
修复根面龋要较猞面龋复杂,比如根面龋的清理、成型片与楔子的放入、与邻牙的接触恢复和修复后悬突的处理等。尽管玻璃多聚链烯盐和复合树脂三明治技术已被广泛应用,但玻璃多聚链烯盐和银汞合金三明治技术尚未得以深入的研究。本研究旨在通过玻璃多聚链烯盐垫底,观察银汞合金充填修复Ⅱ类洞型后的洞型抗折强度。  相似文献   
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