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71.
Background. Patients with diabetic sensory neuropathy have significant risk of chronic ulcers. Insufficient nerve-derived mediators such as substance P (SP) may contribute to the impaired response to injury. Mutant diabetic mice (db/db), which develop neuropathy and have delayed healing, may provide a model to study the role of nerves in cutaneous injury.Methods. Skin from human chronic nonhealing ulcers and age-matched control skin was immunohistochemically evaluated for nerves. Nerve counts were also compared in murine diabetic (C57BL/KsJ-m+/+ Lepr(db); db/db) and nondiabetic (db/-) skin. Excisional wounds on the backs of db/db and db/- mice were grouped as: (a) untreated db/- mice; (b) untreated db/db mice; (c) db/db mice with polyethylene glycol (PEG); (d) db/db mice with PEG and SP 10(-9) M; or (e) db/db mice with PEG and SP 10(-6) M.Results. We demonstrated fewer nerves in the epidermis and papillary dermis of skin from human subjects with diabetes. Likewise, db/db murine skin had significantly fewer epidermal nerves than nondiabetic littermates. We confirmed increased healing times in db/db mice (51.7 days) compared to db/- littermates (19.8 days; P 相似文献   
72.
BACKGROUND: This study was performed to verify reports of the decreased accuracy of endorectal ultrasonography (EUS) in preoperative staging of rectal cancer, and to compare the efficacy of 3-dimensional (3D) EUS with that of 2-dimensional (2D) EUS and computed tomography (CT). METHODS: Eighty-six consecutive rectal cancer patients undergoing curative surgery were evaluated by 2D EUS, 3D EUS, and CT scan. RESULTS: The accuracy in T-staging was 78% for 3D EUS, 69% for 2D EUS, and 57% for CT (P < .001-.002), whereas the accuracy in evaluating lymph node metastases was 65%, 56%, and 53%, respectively (P < .001-.006). Examiner errors were the most frequent cause of misinterpretation, occurring in 47% of 2D EUS examinations and in 65% of 3D EUS examinations. By eliminating examiner errors, the accuracy rates in T-staging and lymph node evaluation could be improved to 88% and 76%, respectively, for 2D EUS, and to 91% and 90%, respectively, for 3D EUS. Conical protrusions along the deep tumor border on 3D images were correlated closely with infiltration grade, advanced T-stage, and lymph node metastasis. CONCLUSIONS: We found that 3D EUS showed greater accuracy than 2D EUS or CT in rectal cancer staging and lymph node metastases. Concrete 3D images based on tumor biology appear to provide more accurate information on tumor progression.  相似文献   
73.

Background

The purpose of this study was to assess the reliability of pre-, intra operative, and postoperative limb alignment measurements and investigate the correlation between the measurements in biplanar medial opening-wedge high tibial osteotomy.

Methods

This study enrolled 59 knees undergoing biplanar opening-wedge high tibial osteotomy for primary medial osteoarthritis with varus deformity. Preoperative and postoperative standing lower leg radiographs and intraoperative fluoroscopic images were taken. Two independent examiners analyzed the radiologic data to assess lower limb alignment and mechanical axis (MA) deviation (percentage of MA position on tibial plateau). The effect of preoperative hip-knee-ankle angle and MA deviation, age, sex, body mass index (BMI), and joint line convergence angle on the discrepancy between intraoperative and postoperative MA deviation was analyzed.

Results

The mean preoperative hip-knee-ankle angle and MA deviation were varus 7.7 ± 3.3° and 14.1 ± 15.1%, respectively. After osteotomy, the mean intraoperative postosteotomy MA deviation was 57.9 ± 2.1% in supine position, and the mean post-operative MA deviation increased to 63.9 ± 2.9% on standing radiographs. The mean difference between intraoperative postosteotomy MA deviation and postoperative MA deviation was 6.1 ± 2.2%. Linear regression analysis between intraoperative postosteotomy MA deviation and postoperative MA deviation showed a statistically significant linear relationship (R2 = 0.449; P < .001). Multivariate regression analysis revealed that preoperative joint line convergence angle (β = 0.856; P < .001) and BMI (β = 0.349; P < .001) were significant positive predictors for the difference in MA deviation.

Conclusion

There was a significant linear relationship between intraoperative postosteotomy MA deviation and postoperative MA deviation following biplanar medial opening-wedge high tibial osteotomy. A greater discrepancy between MA deviations was significantly associated with higher BMI and joint line convergence angle.  相似文献   
74.
75.
Priapism is rare and usually unpredictable. High-flow priapism is caused by unregulated arterial inflow. Antecedent trauma is the most commonly described etiology. This condition does not require emergent treatment. The initial management of high-flow priapism should be observation, because treatment-related erectile dysfunction may appear. We report a case of high-flow priapism by perineal trauma in a 27-year-old man. His corpora were typically tumescent, but not completely rigid. He could not have sexual intercourse. Blood from the corpus cavernosum was normally oxygenated. Color duplex ultrasonography was performed in the lithotomy position, scanned at the perineum, showed pseudoaneurysmal appearance. Selective internal pudendal arteriography showed a right cavernous arterial extravasation. Superselective embolization of right internal pudendal arteries was performed with an autologous clot. After the procedure, detumescence was achieved as well as erectile function. We recommend superselective arterial embolization as the management of high flow priapism to patients who request treatment.  相似文献   
76.
77.
ObjectiveTo investigate the image quality (IQ) and apparent diffusion coefficient (ADC) of reduced field-of-view (FOV) di-ffusion-weighted imaging (DWI) of pancreas in comparison with full FOV DWI.ResultsOn qualitative analysis, reduced FOV DWI showed better anatomic structure visualization (2.76 ± 0.79 at b = 0 s/mm2 and 2.81 ± 0.64 at b = 400 s/mm2), lesion conspicuity (3.11 ± 0.99 at b = 0 s/mm2 and 3.15 ± 0.79 at b = 400 s/mm2), IQ score (8.51 ± 2.05 at b = 0 s/mm2 and 8.79 ± 1.60 at b = 400 s/mm2), and higher clinical utility (3.41 ± 0.64), as compared to full FOV DWI (anatomic structure, 2.18 ± 0.59 at b = 0 s/mm2 and 2.56 ± 0.47 at b = 500 s/mm2; lesion conspicuity, 2.55 ± 1.07 at b = 0 s/mm2 and 2.89 ± 0.86 at b = 500 s/mm2; IQ score, 7.13 ± 1.83 at b = 0 s/mm2 and 8.17 ± 1.31 at b = 500 s/mm2; clinical utility, 3.14 ± 0.70) (p < 0.05). Artifacts were significantly improved on reduced FOV DWI (2.65 ± 0.68) at b = 0 s/mm2 (full FOV DWI, 2.41 ± 0.63) (p < 0.001). On quantitative analysis, there were no significant differences between the 2 DWI sequences in ADCs of various pancreatic lesions and parenchyma (p > 0.05). ADCs of adenocarcinomas (1.061 × 10-3 mm2/s ± 0.133 at reduced FOV and 1.079 × 10-3 mm2/s ± 0.135 at full FOV) and neuroendocrine tumors (0.983 × 10-3 mm2/s ± 0.152 at reduced FOV and 1.004 × 10-3 mm2/s ± 0.153 at full FOV) were significantly lower than those of parenchyma (1.191 × 10-3 mm2/s ± 0.125 at reduced FOV and 1.218 × 10-3 mm2/s ± 0.103 at full FOV) (p < 0.05).ConclusionReduced FOV DWI of the pancreas provides better overall IQ including better anatomic detail, lesion conspicuity and subjective clinical utility.  相似文献   
78.
ObjectiveTo evaluate the image characteristics of subtraction magnetic resonance venography (SMRV) from time-resolved contrast-enhanced MR angiography (TRMRA) compared with phase-contrast MR venography (PCMRV) and single-phase contrast-enhanced MR venography (CEMRV).ResultsSingle-phase contrast-enhanced MR venography showed better image quality (median score 4 in both reviewers) than did the other two MRVs (p < 0.001), whereas SMRV (median score 3 in both reviewers) and PCMRV (median score 3 in both reviewers) had similar image quality (p ≥ 0.951). SMRV (median score 0 in both reviewers) suppressed arterial signal better than did the other MRVs (median score 1 in CEMRV, median score 2 in PCMRV, both reviewers) (p < 0.001). The dural sinus score of SMRV (median and interquartile range [IQR] 48, 43-50 for reviewer 1, 47, 43-49 for reviewer 2) was significantly higher than for PCMRV (median and IQR 31, 25-34 for reviewer 1, 30, 23-32 for reviewer 2) (p < 0.01) and did not differ from that of CEMRV (median and IQR 50, 47-52 for reviewer 1, 49, 45-51 for reviewer 2) (p = 0.146 in reviewer 1 and 0.123 in reviewer 2). The SNR and CNR of SMRV (median and IQR 104.5, 83.1-121.2 and 104.1, 74.9-120.5, respectively) were between those of CEMRV (median and IQR 150.3, 111-182.6 and 148.4, 108-178.2) and PCMRV (median and IQR 59.4, 49.2-74.9 and 53.6, 43.8-69.2).ConclusionSubtraction magnetic resonance venography is a promising MRV method, with acceptable image quality and good arterial suppression.  相似文献   
79.
Kim DH  Lee NY  Sohn SK  Baek JH  Kim JG  Suh JS  Lee KB  Shin IH 《Transplantation》2005,79(11):1615-1622
BACKGROUND: The current study attempted to evaluate the association between IL-10 promoter gene polymorphism and transplant outcomes including the occurrence of chronic graft-versus-host disease (GVHD) and its clinical course during systemic immunosuppressive treatment (IST) among 60 recipients of cytokine-mobilized peripheral blood stem cell (PBSC) from HLA-matched sibling donors. METHODS: We analyzed 3 single-nucleotide polymorphisms in proximal region of IL-10 promoter gene (-1082/-819/-592). RESULTS: In the current study, only two haplotypes (1082*A/819*T/592*A [ATA] and 1082*A/819*C/592*C [ACC]) were found. An increased occurrence of chronic GVHD was noted dependent on the IL-10 haplotypes (43% vs. 68% vs. 96% in ACC/ACC vs. ATA/ACC vs. ATA/ATA haplotype, P=0.003). In a logistic regression based on multinomial model, ATA/ATA homozygote had 7-fold increasing risk of the development of chronic GVHD compared with ACC/ACC homozygote. The incidence of chronic GVHD at 1 year was 46%+/-20%, 64%+/-10%, and 82%+/-5% in ACC/ACC, ATA/ACC and ATA/ATA group, respectively (P=0.0266). Plus, the duration of systemic IST was significantly shorter in recipients without ATA-haplotype comparing with those with ATA haplotype (339 days vs. 1,146 days, P=0.0091). CONCLUSION: IL-10 promoter gene polymorphism was found to be apparently associated with chronic GVHD after allogeneic peripheral blood stem cell transplantation from HLA-matched sibling donors.  相似文献   
80.
100 multivisceral transplants at a single center   总被引:7,自引:0,他引:7       下载免费PDF全文
OBJECTIVE: The objective of this study was to summarize the evolution of multivisceral transplantation over a decade of experience and evaluate its current status. SUMMARY BACKGROUND DATA: Multivisceral transplantation can be valuable for the treatment of patients with massive abdominal catastrophes. Its major limitations have been technical and rejection of the intestinal graft. METHODS: This study consisted of an outcome analysis of 98 consecutive patients who received multivisceral transplantation at our institution. This represents the largest single center experience to date. RESULTS: The most common diseases in our population before transplant were intestinal gastroschisis and intestinal dysmotility syndromes in children, and mesenteric thrombosis and trauma in adults. Kaplan Meier estimated patient and graft survivals for all cases were 65% and 63% at 1 year, 49% and 47% at 3 years, and 49% and 47% at 5 years. Factors that adversely influenced patient survival included transplant before 1998 (P = 0.01), being hospitalized at the time of transplant (P = 0.05), and being a child who received Campath-1H induction (P = 0.03). Among 37 patients who had none of these 3 factors (15 adults and 22 children), estimated 1- and 3-year survivals were 89% and 71%, respectively. Patients transplanted since 2001 had significantly less moderate and severe rejections (31.6% vs 67.6%, P = 0.0005) with almost half of these patients never developing rejection. CONCLUSIONS: Multivisceral transplantation is now an effective treatment of patients with complex abdominal pathology. The incidences of serious acute rejection and patient survival have improved in the most recent experience. Our results show that the multivisceral graft seems to facilitate engraftment of transplanted organs and raises the possibility that there is a degree of immunologic protection afforded by this procedure.  相似文献   
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