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71.
Abstract: Background: Post‐transplant lymphoproliferative disease (PTLD) is a life‐threatening complication of immunosuppression following transplantation. Epstein–Barr virus (EBV) and gammopathy in serum are associated with PTLD, but these two parameters have not been evaluated in parallel for their association with PTLD. Methods: We evaluated the incidence of EBV load positivity, gammopathy, and protein expression in sera from all PTLD patients diagnosed at our hospital during the past seven yr. Results were compared with those of a control group including matched transplanted patients who did not develop PTLD. Results: Seven of 10 PTLD patients presented EBV+ PTLD, for which five patients had detectable serum EBV DNA levels compared with none of 38 controls (RR between two groups =121, p < 0.0001). Five out of 10 patients had gammopathy at PTLD diagnosis compared with 5/38 controls (RR between two groups = 6.6, p = 0.022). Additionally, protein serum analysis by high‐resolution two‐dimensional gel electrophoresis and image examination failed to evidence specific abnormality in patients with PTLD compared with controls. Conclusions: Our results confirm an association between EBV in sera and gammopathy with PTLD, and highlight the high specificity of the former analysis. Whether a combination of both analyses will improve the clinical detection of PTLD remains to be evaluated in a larger prospective cohort study.  相似文献   
72.
73.
We report on a 7 year-old-girl with mandibulo-acral dysplasia. When she was 3 years of age it mimicked scleroderma because of skin atrophy and later on a Hutchinson-Gilford progeria syndrome (HGP). Acro-mandibular dysplasia was diagnosed because of facial hypoplasia and mandibular hypoplasia. The bilateral proximal mid-humeral notch seen in this case is unusual. Received: 22 June 2000 Revision requested: 10 July 2000 Revision received: 7 August 2000 Accepted: 10 August 2000  相似文献   
74.

Background

Stromal mesenchyme cells play an important role in epithelial differentiation and likely in cancer as well. Induction of epithelial differentiation is organ-specific, and the genes responsible could be identified through a comparative genomic analysis of the stromal cells from two different organs. These genes might be aberrantly expressed in cancer since cancer could be viewed as due to a defect in stromal signaling. We propose to identify the prostate stromal genes by analysis of differentially expressed genes between prostate and bladder stromal cells, and to examine their expression in prostate cancer.

Methods

Immunohistochemistry using antibodies to cluster designation (CD) cell surface antigens was first used to characterize the stromas of the prostate and bladder. Stromal cells were prepared from either prostate or bladder tissue for cell culture. RNA was isolated from the cultured cells and analyzed by DNA microarrays. Expression of candidate genes in normal prostate and prostate cancer was examined by RT-PCR.

Results

The bladder stroma was phenotypically different from that of the prostate. Most notable was the presence of a layer of CD13+ cells adjacent to the urothelium. This structural feature was also seen in the mouse bladder. The prostate stroma was uniformly CD13-. A number of differentially expressed genes between prostate and bladder stromal cells were identified. One prostate gene, proenkephalin (PENK), was of interest because it encodes a hormone. Secreted proteins such as hormones and bioactive peptides are known to mediate cell-cell signaling. Prostate stromal expression of PENK was verified by an antibody raised against a PENK peptide, by RT-PCR analysis of laser-capture microdissected stromal cells, and by database analysis. Gene expression analysis showed that PENK expression was down-regulated in prostate cancer.

Conclusion

Our findings show that the histologically similar stromas of the prostate and bladder are phenotypically different, and express organ-specific genes. The importance of these genes in epithelial development is suggested by their abnormal expression in cancer. Among the candidates is the hormone PENK and the down-regulation of PENK expression in cancer suggests a possible association with cancer development.  相似文献   
75.

OBJECTIVES

To determine the technical feasibility and reproducibility of pure natural orifice transluminal endoscopic surgery (NOTES) transvaginal nephrectomy using NOTES‐specific instrumentation, with no transabdominal assistance.

MATERIALS AND METHODS

Five female farm pigs (mean weight 45 kg) had a right NOTES nephrectomy, using a single‐channel gastroscope in the first three pigs and a dual‐channel gastroscope in the remaining two. The peritoneal cavity was accessed through the posterior fornix of the vagina. Dissection was started at the lower pole of the kidney, and the ureter was retracted laterally and followed towards the hilum. An XL articulated 60 cm endo‐GIA stapler (US Surgical, Norwalk, CO, USA), inserted transvaginally via a separate vaginal incision, was used for tissue retraction and renal hilar transection. The kidney was freed, entrapped in an impermeable sac, and extracted intact transvaginally.

RESULTS

All five procedures were successful with no addition of a transabdominal laparoscopic port or open conversion. The total operative duration decreased from 200 min in the first pig to 60 min in the last (mean 113 min); the mean blood loss was <50 mL, the mean kidney length was 13.9 cm and the weight was 142 g. There were no intraoperative complications; at autopsy, there was no pelvic or bowel injury.

CONCLUSIONS

Pure NOTES transvaginal nephrectomy is feasible in the porcine model. It has the potential of a less morbid approach, providing truly scar‐less surgery. Further development of instrumentation is necessary.  相似文献   
76.
77.

Objective

To evaluate the accuracy of abdominal radiography (AXR) for the detection of residual cocaine packets by comparison with computed tomography (CT).

Methods

Over a 1-year period unenhanced CT was systematically performed in addition to AXR for pre-discharge evaluation of cocaine body packers. AXR and CT were interpreted independently by two radiologists blinded to clinical outcome. Patient and packet characteristics were compared between the groups with residual portage and complete decontamination.

Results

Among 138 body packers studied, 14 (10 %) had one residual packet identified on pre-discharge CT. On AXR, at least one reader failed to detect the residual packet in 10 (70 %) of these 14 body packers. The sensitivity and specificity of AXR were 28.6 % (95 % CI: 8.4–58.1) and 100.0 % (95 % CI: 97.0–100.0) for reader 1 and 35.7 % (95 % CI: 12.8–64.9) and 97.6 % (95 % CI: 93.1–99.5) for reader 2. There were no significant patient or packet characteristics predictive of residual portage or AXR false negativity. All positive CT results were confirmed by delayed expulsion or surgical findings, while negative results were confirmed by further surveillance.

Conclusion

Given the poor performance of AXR, CT should be systematically performed to ensure safe hospital discharge of cocaine body packers.

Key Points

? Both abdominal radiography and computed tomography can identify gastrointestinal cocaine packets. ? Ten per cent of body packers had residual packets despite two packet-free stools. ? Seventy per cent of these residual packets were missed on AXR. ? No patient or packet characteristics predicted residual packets or AXR false negativity. ? CT is necessary to ensure safe medical discharge of body packers.  相似文献   
78.
PURPOSE: To compare the performance of the conventional diaphragm navigator (DNAV) and the recently developed cardiac fat navigator (FatNAV) in suppressing respiration-induced cardiac motion in free-breathing 3D balanced steady-state free precession coronary MRA (SSFP CMRA). MATERIALS AND METHODS: In 16 healthy volunteers the right coronary artery (RCA) was imaged at 1.5T using a navigator-gated 3D SSFP CMRA sequence. DNAV and FatNAV gating were performed in random order. Image quality difference was scored by three experienced readers blinded to the gating technique. Blood signal-to-noise ratio (SNR), blood-to-myocardium contrast-to-noise ratio (CNR), and navigator efficiency were calculated. RESULTS: Diagnostically interpretable CMRA was obtained successfully in all 16 subjects with FatNAV gating (0% failure rate) and only 14 subjects with DNAV gating (12% failure rate). Compared to DNAV gating, FatNAV gating provided similar SNR and CNR, better image quality (P < 0.01), and 28% improvement in navigator efficiency (P = 0.002). CONCLUSION: FatNAV gating provides more effective motion suppression and better image quality than DNAV gating for free-breathing 3D SSFP CMRA of the RCA in healthy subjects.  相似文献   
79.
Many palliative interventions have been proposed for patients in whom rotator cuff repair is not feasible as a result of advanced fatty infiltration, definitive loss of tendons, and proximal humeral migration. The long head of the biceps tendon has been proposed as a source of pain in patients with rotator cuff tears. This article presents a review of current concepts on the rationale for arthroscopic biceps tenotomy or tenodesis, and evaluates the objective, subjective, and radiographic results of these palliative procedures. On the basis of different studies, it seems that isolated arthroscopic biceps tenotomy or tenodesis is a valuable option for the treatment of rotator cuff tears in selected patients. Although it does not improve shoulder strength, tenotomy or tenodesis reduces pain and improves the functional range of motion with a high degree of patient satisfaction. However, the progressive radiographic changes that occur with long standing rotator cuff tears are not altered.  相似文献   
80.
Purpose  Respiratory motion causes uptake in positron emission tomography (PET) images of chest structures to spread out and misregister with the CT images. This misregistration can alter the attenuation correction and thus the quantisation of PET images. In this paper, we present the first clinical results for a respiratory-gated PET (RG-PET) processing method based on a single breath-hold CT (BH-CT) acquisition, which seeks to improve diagnostic accuracy via better PET-to-CT co-registration. We refer to this method as “CT-based” RG-PET processing. Methods  Thirteen lesions were studied. Patients underwent a standard clinical PET protocol and then the CT-based protocol, which consists of a 10-min List Mode RG-PET acquisition, followed by a shallow end-expiration BH-CT. The respective performances of the CT-based and clinical PET methods were evaluated by comparing the distances between the lesions’ centroids on PET and CT images. SUVMAX and volume variations were also investigated. Results  The CT-based method showed significantly lower (p = 0.027) centroid distances (mean change relative to the clinical method = −49%; range = −100% to 0%). This led to higher SUVMAX (mean change = +33%; range = −4% to 69%). Lesion volumes were significantly lower (p = 0.022) in CT-based PET volumes (mean change = −39%: range = −74% to −1%) compared with clinical ones. Conclusions  A CT-based RG-PET processing method can be implemented in clinical practice with a small increase in radiation exposure. It improves PET-CT co-registration of lung lesions and should lead to more accurate attenuation correction and thus SUV measurement.  相似文献   
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