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21.
Background. Vascular calcification is an independent determinantof cardiovascular events in maintenance haemodialysis (HD) patients.It is not known whether acute changes of the serum calcium concentrationbefore and after HD (Ca) are associated with the developmentof aortic calcification. Methods. We enrolled 71 patients dialysed with a dialysate with3.0 mEq/l calcium and determined their aortic calcificationindex (ACI) by abdominal computed tomography twice at an intervalof 3 years. To identify the factors contributing to the rateof progression of aortic calcification, we analysed the averagevalues for clinical and laboratory data obtained between thefirst and second evaluations of ACI. Results. The second ACI (mean ± SD: 80.2 ± 63.9)was significantly greater than the first ACI (61.0 ±61.0) after an interval of 35.8 ± 4.2 months. The annualizedchange of ACI (ACI/year) was significantly and directly associatedwith the Ca and C-reactive protein (CRP) (both P < 0.001,P for trend). Stepwise multivariate regression analysis revealedthat ACI/year was positively and independently associated withCRP, presence of diabetes mellitus and Ca, but negatively associatedwith a premenopausal status in women. Similarly, Ca was positivelyand independently associated with ACI/year and the ultrafiltrationrate, but was negatively associated with pre-HD Ca. Conclusion. The increase of serum calcium after HD was relatedto the rate of progression of aortic calcification. Excess calciumis transferred into patients on HD when using a dialysate of3.0 mEq/l calcium. This may be a risk factor for the developmentof vascular calcification.  相似文献   
22.
Conventional corticocancellous bone grafts are known to revascularize gradually and to become repopulated with osteocytes and other types of cells. This study was conducted to study the origin of the cells found within conventional bone grafts as a function of time, using a new method which accurately identifies donor cells transplanted with the graft. The technique requires the transplantation of a 25-mm tibial diaphyseal bone graft from a male rat to a female isogenous recipient, placed anatomically in the tibia. The presence and relative proportion of cells containing the Y-chromosome (i.e., originating from the bone graft) was determined 4, 8, and 12 weeks after transplantation. At these times, genomic DNA was extracted from the grafted bones and a polymerase chain reaction (PCR) specific for the sex-determining region of the Y-chromosome (Sry) was performed, with appropriate controls. Sry-specific bands were evident in none out of three grafts at 4 weeks, two out of three at 8 weeks, and all grafts at 12 weeks. These data demonstrate that not all cells within a conventional graft result from "creeping substitution" of necrotic bone. Instead, a small number of intrinsic cells from a nonvascularized corticocancellous structural graft survive and proliferate over time. Received: June 19, 2001 / Accepted: October 30, 2001  相似文献   
23.
World Journal of Surgery - We started performing sentinel node navigation surgery (SNNS) for patients with early gastric cancer (EGC) using infrared ray electronic endoscopy (IREE) with indocyanine...  相似文献   
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25.
Noonan syndrome (NS) is an autosomal dominant disorder characterized by facial anomalies, short stature, chest deformity, congenital heart diseases, and other comorbidities. The challenges faced during anesthetic management of patients with NS could be due to congenital heart diseases, hemostatic disorders, and airway anomalies. Here we describe dental treatment under general anesthesia performed for a 28-year-old man with NS. He had characteristic features of NS along with mild pulmonary valve stenosis. Dental treatment under general anesthesia was performed successfully on 13 occasions with nasotracheal intubation under curve-tipped suction catheter guidance or insertion of a reinforced laryngeal mask airway. This case suggests that for patients with NS, who might present several challenges, dental anesthesiologists should consider the extent of the patient''s disorders to enable them to perform dental treatment safely under general anesthesia.Key Words: Repeated general anesthesia, Noonan syndromeNoonan syndrome (NS) is an autosomal dominant disorder and was first reported by Noonan and Ehmke.1 The primary features of this multisystem disorder include hypertelorism, low-set ears, down-slanting eyes, a webbed neck, congenital heart diseases, short stature, chest deformity, and intellectual impairment.2,3 NS affects males and females equally and has an estimated incidence of 1 in 1000 to 1 in 2500 live births.2,4The challenges faced during anesthetic management of patients with NS could be due to congenital heart diseases, hemostatic disorders, and airway anomalies.58 The present report describes repeated administration of general anesthesia performed by adopting nasotracheal intubation or reinforced laryngeal mask airway insertion for a patient with NS at the time of dental treatment in our hospital.  相似文献   
26.

Background

Recently, various femoral head fixation devices (HFDs) for trochanteric fractures have become available. However, there are some cases in which femoral head rotation with excessive sliding of the HFD is observed and it is often followed by cutout. The purpose of this study is to compare the ability of the three types of HFDs to prevent femoral head rotation.

Methods

Between July 2005 and December 2009, 206 patients aged over 60 years with trochanteric fractures who had undergone surgical treatment using a short femoral nail in our institution were enrolled into the study. We used the gamma 3 nail (GMN) as the screw-type HFD in 66 cases, the gliding nail (GLN) as a non-cylindrical blade in 76 cases, and the proximal femoral nail antirotation (PFNA) as a cylindrical blade in 64 cases. The sliding length of HFDs and the occurrence of femoral head rotation were evaluated by assessing radiographs as the main outcome, and the results were compared among these devices.

Results

A comparison of the degree of sliding in the GMN group showed that femoral head rotation was observed significantly more frequently in cases with rotation. Further, it appeared that femoral head rotation occurred more frequently in comminuted fractures. However, no significant differences between the sliding lengths of the different HFDs were observed among three groups. Femoral head rotation was observed in 15 cases of GMN (22.7%), 0 case of GLN, and 5 case of PFNA (7.8%). Significant differences with regard to the occurrence of femoral head rotation were observed among the three groups. Furthermore, significant differences were also observed between GLN and PFNA with respect to the occurrence of femoral head rotation.

Conclusions

The ability to stabilize femoral head appears to be greater with blade-type materials than with screw-type materials. Furthermore, we believe that a non-cylindrical blade is preferable to a cylindrical blade for the surgical treatment of comminuted, unstable trochanteric fractures in order to prevent femoral head rotation and cut-out.  相似文献   
27.
We experienced a case of a huge hemangioma occupying the oropharyngeal space in an 11-year-old child. Although urgent surgical tracheostomy under local anesthesia was suggested initially, medical interview and findings of computerized tomography and fiberoptic laryngoscopy revealed that the airway of the patient was relatively stable when she was in the semi-left decubitus position. General anesthetic induction would have had potential risks of airway obstruction. Thus, after placing the patient in the semi-left decubutus position, we chose semi-awake induction to secure the airway. With a small dose of fentanyl, we accomplished orotracheal intubation. In this report, we discuss the importance of referring to an airway management algorithm when encountering a difficult airway.  相似文献   
28.
BACKGROUND: Sepsis is an arginine-deficient state and is associated with overproduction of nitric oxide (NO) by inducible nitric oxide synthase (iNOS). It has been indicated that low plasma levels of arginine are related to high mortality rates in sepsis. Arginine, however, is also known to be a precursor of NO. Therefore, administration of arginine in septic patients remains controversial. We examined the effects of co-administration of arginine and aminoguanidine, a selective iNOS inhibitor, on sepsis, using rat models. METHOD: Sepsis was induced in rats by cecal ligation and puncture (CLP). Effects of separate and combined administration of arginine and aminoguanidine were investigated by comparing plasma levels of arginine, expressions of heme oxygenase (HO)-1 and HO-2 in liver and lung, and nitrite + nitrate (NOx) excretion in urine, as well as neuroendocrine responses in urine in the early phase of sepsis. Seven-day survival rates were also examined. RESULTS: A combination of arginine and aminoguanidine recovered the plasma level of arginine at 6 h post-CLP, decreased expression of HO-1 in liver and lung at 24 h post-CLP, decreased urinary excretion of epinephrine, norepinephrine, dopamine, and 17-hydroxycorticosteroid in the first 24 h post-CLP, and increased 7-d survival. CONCLUSION: It is demonstrated that administration of arginine together with the selective iNOS inhibitor in the early phase of sepsis restores plasma arginine, reduces oxidative stress by probably maintaining NO derived from constitutive NOS, and attenuates neuroendocrine stress responses. This co-administration may be a beneficial treatment approach against sepsis.  相似文献   
29.
We report the case of a patient with leg edema after large-diameter metal-on-metal total hip arthroplasty. At 1 year and 2 months after primary left large-diameter metal-on-metal total hip arthroplasty, the patient complained of left leg edema. At first, we suspected deep venous thrombosis. However, deep venous thrombosis was not detected by venous ultrasonographic examination. Computed tomography imaging revealed a mass in front of the iliac fossa. The mass compressed the left iliac artery and vein. We therefore believed that this lesion was the cause of the leg edema and performed resection of the mass. The resected mass consisted of necrotic tissue infiltrating inflammation cells, so it was diagnosed as pseudotumor. Unilateral leg edema disappeared gradually after the resection.  相似文献   
30.

Objectives

The purpose of this study was to establish the factors influencing the masticatory performance of older subjects with varying degrees of tooth loss and associated numbers of posterior occlusal contacts.

Methods

The subjects consisted of 1274 independently living people aged 60 years and over. Individuals with partially or fully edentulous arches without a denture replacement or those having any symptoms related to an oral problem were excluded from the study participants. Masticatory performance, maximal occlusal force and stimulated whole saliva were measured. Subjects were grouped into three categories by posterior occlusal contact, according to the Eichner Index. Group A had contacts in four support zones; group B had one to three zones of contact or contact in the anterior region only; and group C had no support zones at all, although a few teeth could still remain.

Results

The masticatory performance in groups B and C was found to be 81% and 50% of that of group A, respectively. The multiple linear regression analysis showed that in all the groups, occlusal force was significantly associated with masticatory performance. In groups A and B, the number of residual teeth was significantly associated with masticatory performance, whereas in group C, it had no significant relationship with masticatory performance. Salivary flow rate had a significant correlation with masticatory performance only in group C.

Conclusions

Declines in occlusal contact, occlusal force and salivary flow appear to be associated with reduction of masticatory performance in older adults. However, the crucial factors for masticatory performance varied, depending on the phase of occlusal collapse.  相似文献   
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