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1.
2.

Objective

The advantage of arteriovenous fistulas (AVFs) in older patients requiring dialysis is controversial. We reviewed our vascular access experience in patients ≥70 years of age (older group) compared with younger patients.

Methods

We analyzed consecutive patients who underwent access surgery between 2013 and 2016. Primary success (PS) and primary patency (PP) data were analyzed between the older and younger groups before and after propensity score matching of the patients' characteristics and access composition. PS was defined as the achievement of access function that was amenable to two sessions of successful cannulation without early occlusion or maturation failure requiring revision. PP was defined as the time with uninterrupted patency without intervention.

Results

A total of 594 consecutive accesses were created among 563 patients, of whom 119 were allocated into each group after propensity score matching. In the whole cohort, 193 accesses (32.5%) were performed in older patients. AVFs were performed in 130 (67.4%) older patients and 293 (73.1%) younger patients. Regarding AVFs, the PS rate (83.6% in the older group vs 94.3% in the younger group; P = .001) and the overall PP at 6 and 12 months (73.1% and 57.1%, respectively, in the older group vs 86.7% and 77.7%, respectively, in the younger group; P = .009) were lower in the older group than in the younger group. However, no differences were found in the PS and PP rates for arteriovenous grafts between groups. Regarding the AVF location, the PS rate for forearm AVFs was significantly lower in the older group than in the younger group (76% vs 93%; P < .001); however, the PS rate of the upper arm was not different between the groups (94% vs 97%; P = .425). In the patients with PS, the PP rate of AVFs was similar between the two groups. In the older group with forearm AVFs, the median diameter of the radial artery was larger in the patients with PS than in the patients without PS (2.20 mm with PS vs 2.00 mm without PS; P = .008). The propensity score matching results demonstrated similar trends for the whole cohort, with lower PS (P = .042) and PP rates (P = .023) for AVF in the older group.

Conclusions

The outcomes after AVF were poorer in the older group than in the younger group, which was primarily due to unsatisfactory outcomes in patients with forearm AVFs. Thus, stricter criteria, especially regarding the radial artery diameter, should be applied for forearm AVFs in older patients, and additional research is necessary to delineate the risk factors for primary failure.  相似文献   
3.

Background

In Leriche syndrome, postoperative graft thrombosis remains one of the most significant clinical challenges.

Methods

We reviewed 51 patients who underwent surgery for aortoiliac occlusive disease at our hospital from January 2007 to December 2014. The factors associated with graft patency were determined using the Cox proportional hazard model.

Results

The 2-year prosthetic graft patency rate was 72.5%. Younger age (p = 0.017, Odd ratio (OR) = 1.112), postoperative uncontrolled hypertension (p = 0.044, OR = 3.797), and associated Trans Atlantic Inter-Society Consensus for the Management of Peripheral Arterial Disease II (TASC II) D femoropopliteal lesion (p = 0.008, OR = 11.139) were significantly related factors for prosthetic graft patency after surgical repair. The existing comorbidities of the patients that indicated the need for axillo-bifemoral bypass seemed to be related to lower graft patency or other complications.

Conclusions

For better graft patency after an open surgical repair of Leriche syndrome, strict postoperative hypertension control and distal run-off resolution are necessary.  相似文献   
4.
Background/purpose: Vitiligo and nevus depigmentosus (ND) present similar hypopigmented macules with significantly different prognoses. Although the distinction between the two diseases is important, differential diagnosis relies on medical history and physical examination, which is far from decisive in some cases. The Mexameter® is an objective skin color-measuring device, and has been reported to provide a reproducible and sensitive means of quantifying small skin color differences. In this study, we investigated the usefulness of a Mexameter® for discriminating these diseases.
Methods: A selection of 202 hypopigmented skin lesions (182 from vitiligo and 20 from ND) were the objects of this study. Using a Mexameter, MIs were obtained from lesions and symmetrically located control skin. RMIs, ratios of the MIs of lesional skins to control skins, were calculated.
Results: The mean MIs and RMIs were significantly different for vitiligo and ND. The mean RMI of ND lesions was 74±13, which was significantly higher than that of vitiligo lesions (50±24). No ND lesion had an RMI of <50%.
Conclusion: This study shows that the Mexameter®, an objective pigment-measuring device, can be used to achieve a more accurate diagnosis of hypopigmentary disorders, and that the relative melanin index (RMI), which represents the relative pigment levels, might be a more effective parameter than the melanin index (MI) itself for comparing pigmentation differences.  相似文献   
5.
Critical size defect in the canine mandible.   总被引:3,自引:0,他引:3  
OBJECTIVE: The purpose of this study was to determine the minimum size defect in a canine mandible that would not spontaneously heal during the dog's natural life (the critical size defect). STUDY DESIGN: Sixteen adult female mongrel dogs underwent continuity resection on both sides of the mandible to create bilateral defects. In 8 dogs, mandibular defects ranging from 5 to 20 mm were created with periosteal resection. In the other 8 dogs, mandibular defects ranging from 30 to 60 mm were created preserving the periosteum. The dogs were then killed at 6 months and the defects examined using radiographs and histologic analysis. RESULTS: When the periosteum was removed, mandibular defects greater than 15 mm failed to heal across the entire defect. However, when the periosteum was preserved, mandibular defects needed to be greater than 50 mm in order to fail to heal. CONCLUSION: The critical size defect in a canine mandible model is 15 mm when the periosteum is removed and 50 mm when the periosteum is preserved.  相似文献   
6.
UPSC has been identified as a distinct variant of endometrial cancer and it has been reported to be associated with more aggressive behavior and a worse prognosis compared to endometrioid adenocarcinomas of the endometrium. Various studies have demonstrated survival rates of 15–51% for clinical stage I disease and 35–90% for surgical stage I/II disease. Aside from the very limited number of studies that incorporate comprehensive surgical staging, the majority of these reports used clinical parameters for staging or very limited surgical staging techniques and information.
A significant amount of controversy surrounds the optimal management of patients with stage I UPSC, and appropriate management of these patients has yet to be firmly established. The low incidence of this particular type of cancer, the variety of surgical interventions, and the wide variety of post-operative adjuvant therapies have made it extremely difficult to identify the optimal management of patients with UPSC. Prior to 2004, adjuvant treatment recommendations for surgical stage I UPSC were largely based on very small retrospective patient series (<20 patients), only a fraction of which included surgically staged patients. A recent publication reported the outcomes of surgical stage I UPSC patients from four institutions (1) . Recurrence rates were lower than that published in previous studies, suggesting a potential benefit of comprehensive surgical staging in these patients. The risk of recurrence and mean overall survival were similar between surgical stage I UPSC patients who were managed conservatively versus those treated with adjuvant radiation therapy. Moreover, this study also suggests a potential benefit of adjuvant chemotherapy in these patients.  相似文献   
7.
Pituitary abscess is a rare and potentially lethal condition. Pituitary abscess in a pregnant woman has not been previously described. A 38-year-old pregnant woman (34 weeks gestation) with a pituitary mass complained of a progressive headache and sudden visual impairment. She was afebrile and had no inflammatory symptoms on admission. On MRI, the preoperative diagnosis was pituitary adenoma with sphenoid sinusitis. She underwent an uncomplicated transsphenoidal procedure for removal of the pituitary mass. The next day, labor commenced and a healthy preterm baby was delivered. Pathologic examination of the intrasellar mass showed polymorphonuclear cells, debris and no tumor cells. The sellar contents were cultured and Streptococcus viridans was grown. To our knowledge this is the first case of pituitary abscess reported during pregnancy. Although the patient was pregnant, the transsphenoidal approach was safe for the mother and the fetus. Surgical drainage and antibiotic therapy are required for the definitive treatment of this condition.  相似文献   
8.
9.
1. Fifty-five intact and six baroreceptor denervated and vagotomized cats of either sex were anaesthetized intraperito-neally with urethane (400 mg/kg) and a-chloralose (40 mg/kg). Responses of the systemic arterial pressure (SAP), mean SAP (MSAP) and sympathetic vertebral nerve (VNA) and renal nerve activities (RNA) were recorded. 2. In intact animals, monosodium L-glutamate (Glu, 0.1 mol/L, 50 nL) was microinjected into pressor areas of the locus coeruleus (LC), gigantocellular tegmental field (GTF), rostral ventrolateral medulla (RVLM) and dorsomedial medulla (DM), and the depressor areas of caudal ventrolateral medulla (CVLM). The induced actions were compared before and after microinjection of either glutamate antagonists, glutamate diethylester (GDEE, 0.5 mol/L, 50–100nL), a competitive AMPA receptor blocker, or 2-amino-5-phosphonovaleric acid (D-AP5, 0.025 mol/L, 50–100 nL), a competitive N-methyl-D-aspartate (NMDA) receptor blocker. GDEE completely blocked the increases of SAP and VNA elicited from all pressor areas. D-AP5 only partially blocked the pressor but slightly blocked VNA and RNA responses from LC, GTF and DM, particularly those from RVLM. Neither GDEE nor D-AP5 blocked the depressor responses of SAP and two nerve activities elicited from CVLM. 3. In baroreceptor denervated animals, NMDA (2 mmol/L, 50–100 nL) and AMPA (0.2 mmol/L, 50–100 nL) were micro-injected into the same pressor areas of GTF, RVLM and DM and the depressor area of CVLM responsive to Glu activation (0.1 mol/L, 30 nL). In RVLM, DM and CVLM, the results of either NMDA or AMPA were similar to those induced by Glu. However, in GTF, microinjection of either NMDA or AMPA did not induce similar responses to Glu. This suggests that the nature of GTF may differ from RVLM and DM. 4. The above results suggest that the Glu-induced pressor responses from LC, GTF, DM and especially RVLM, are primarily mediated through AMPA receptors. The Glu-induced depressor responses from CVLM may not be predominantly mediated by either AMPA or NMDA receptors. 5. In both baroreceptor-intact and -denervated cats stimulation of the pressor areas often produced an increase of VNA and a decrease of RNA, while in the depressor CVLM decreased both VNA and RNA. The VNA, but not RNA were positively correlated with the pressor responses, while both VNA and RNA were positively correlated with the depressor responses. This may suggest that neurons of the sympathetic vertebral and renal nerves are topographically organized in the brain.  相似文献   
10.
Rett's syndrome(RS) is a progressive neurodegenerative disorder characterized by exclusive occurrence in females, autistic behavior, dementia, gait ataxia, loss of purposeful use of the hands with stereotypic hand movement, and seizures. Initially RS was considered to be very rare; however, recent reports suggest that the prevalence is considerably higher and occurrence is world-wide. Because the pathophysiological process remains unknown, the diagnosis of RS is based mainly on its characteristic clinical features and course. We experienced two cases of RS which, to our knowledge, are the first reported in Korea. It is quite possible that many patients with RS not yet being diagnosed in Korea.  相似文献   
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