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31.

Background

Preservation of movement at the treated segment and possible reduction of adjacent segment effects is assumed to be an advantage of non-fusion technologies over fusion. The aim of this study was to compare the segmental range of motion (ROM) at the operative level, the cranial and caudal adjacent levels and the global lumbar spine ROM (L2-S1) after monosegmental fusion and total disc replacement (TDR).

Patients and methods

Radiographic data was collected from 27 patients with level 1 degenerative disc disease operated at level L4/5. The ROM was assessed at the index level (L4/5), the cranial and caudal adjacent level and for the lumbar spine (L2-S1).

Results

In the TDR group no significant changes of lumbar spine ROM (L2–S1) and segmental ROM (index level, cranial and caudal adjacent level) were noticed. In the fusion group there was a significant reduction of lumbar ROM (L2-S1) and index level ROM. Additionally the relative ROM in the adjacent caudal segment significantly increased while no changes were seen in the cranial segment.

Conclusion

The relative ROM was significantly increased in monosegmental fusion at level L4/5 compared to TDR. To what extent this fact may result in early adjacent segment degeneration in cases of fusion compared to TDR is still unknown.  相似文献   
32.
ABSTRACT

Purpose/Aim: Acute mesenteric ischemia is a syndrome characterized by sudden onset abdominal pain followed by intestinal necrosis. Morbidity and mortality increase with delayed diagnosis. Even with the latest radiological diagnostic methods, early diagnosis and initiation of treatment can be delayed. Using an experimental model, here we aim to determine the relationship between the laboratory parameters used to detect acute mesenteric ischemia and the duration of irreversible ischemia. Materials and Methods: A total of 30 male Wistar albino rats were divided into five groups, all of which underwent general anesthesia: (i) Superior mesenteric artery (SMA) dissection with laparotomy was performed, and blood samples and intestinal segment samples were taken after 2 hr (Sham group); (ii) volvulus of one-third of the small intestines was performed manually by laparotomy, and blood samples and intestinal segment samples were taken after 2 hr (Volvulus group); (iii) SMA was ligated with laparotomy, and blood samples and intestinal segment samples were taken after 2 hr (SMA+ligated 2-hr group); (iv) SMA was ligated with laparotomy, and blood samples and intestinal segment samples were taken after 4 hr (SMA+ligated 4-hr group); and (v) SMA was ligated with laparotomy, and blood samples and intestinal segment samples were taken after 6 hr (SMA+ligated 6-hr group). Results: The mean lactate dehydrogenase (LDH) activities of the SMA+ligated 2-hr and SMA+ligated 6-hr groups were statistically higher than the control group (p = .004). Compared to the Sham and Volvulus groups, the mean lactate level of the SMA+ligated 6-hr group was significantly higher (p = .004). Compared to the Sham and Volvulus groups, the mean D-dimer levels of the SMA+ligated 4-hr and SMA+ligated 6-hr groups were significantly higher (p = .004 and .003, respectively). By histopathological evaluation, we found that pathological damage increased as the ischemia lengthened. Conclusions: Mesenteric ischemia leads to an irreversible loss of intestinal perfusion and an increase in parameters of ischemia. Irreversible tissue damage occurs after 4 hr of ischemia and peaks after 6 hr, whereas parameters of ischemia (D-dimer, LDH, and L-Lactate levels) are highest at 2 hr after the onset of ischemia.  相似文献   
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The objective of the present study was to determine whether preischemic administration of syringic acid (SA) would attenuate renal ischemia-reperfusion injury (IRI). Rats were divided into three groups: Sham group; IR group; and IR?+?SA group. The effects of SA were examined using biochemical parameters including serum ischemia-modified albumin (IMA), total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), tissue superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT) and malondialdehyde (MDA). The apoptosis status and histopathological changes were evaluated. After calculating the score for each histopathological change, the total score was obtained by summing all the scores. In the SA group, MDA, IMA, TOS, and OSI decreased significantly compared to the IR group. After SA administration, the increase in GPx activity was found to be significant. Apoptosis decreased significantly in the SA group compared with the IR group. The total score significantly decreased after administration of SA. Taken together, our findings suggest that SA preconditioning is effective in reducing tissue damage induced in kidney IRI. Renal histology also showed convincing evidence regarding the protective nature of SA.  相似文献   
35.
Purpose The purpose of this study was to compare the effects of anti-adhesion materials in postoperative adhesions. Materials and Methods Rats were assigned to five groups: Group 1: Control. Group 2: chitin layers were used. Group 3: Na-hyaluronate / carboxymethylcellulose layers were used. Group 4: Na-hyaluronate gel was poured into the abdomen. Group 5: methylprednisolone was injected. The adhesion frequency and grade were scored according to Granat. Blood was taken for Hb, AST, BUN and albumin levels determination. Findings The adhesion frequencies (right and left) and grades were as follow in Groups; I: 82%, 91%, 2.63 ± 1.22; II: 8.3%, 25%, 0.58 ± 0.66; III: 17%, 33%, 1.08 ± 1.08; IV: 50%, 58%, 1.41 ± 1.44; V: 50%, 42%, 1.41 ± 1.50. The adhesion phase in all study groups was found significantly low compared to control group, p < 0.05. No difference was observed among serologic and hematological parameters in all groups. Conclusion All the materials used significantly lowered the adhesion frequency and grade.  相似文献   
36.
BACKGROUND: Three percent of patients with acute myocardial infarction are still missed despite the excess number of admissions with chest pain. The purpose of this study was to review the characteristics of patients who were admitted with chest pain, to evaluate the appropriateness of admissions and the outcomes. We also discuss whether use of a prediction rule could have made a difference in the management of these cases. METHODS: We performed retrospective chart review on all patients admitted to the hospitalist service with a diagnosis of chest pain. Each patient was risk stratified using Diamond and Forrester algorithm for probability of coronary artery disease (CAD), retrospectively. Results were analyzed using chi2 test or exact test and Student's t test. RESULTS: Of 260 patients admitted with chest pain to the hospitalist service, only 24 (9.2%) received the final diagnosis of acute coronary syndrome (ACS). The patients in the ACS group were older and more likely to be male and to have a history of hyperlipidemia, CAD, peripheral vascular disease, cerebrovascular disease and percutaneous coronary intervention (PCI). Of 34 patients who underwent cardiac catheterization, 20 (58.8%) had occlusive CAD and 14 of them received PCI. Risk stratification of patients, retrospectively, revealed 28.3% of the total patient population was high risk, while 6.6% of them were low risk. The number of ACS cases was highest in the high risk group, while none was detected in the low risk group. CONCLUSIONS: Our study demonstrated that using a prediction rule could have prevented about 6% of the chest pain admissions. Therefore, the use of risk stratification methods should be encouraged to decrease cost and improve efficiency of care.  相似文献   
37.

Background and Objectives:

The aim of this retrospective study was to compare conventional laparoscopic living-donor nephrectomy with transvaginal natural orifice transluminal endoscopic surgery–assisted living-donor nephrectomy in terms of feasibility and reproducibility.

Methods:

A total of 115 consecutive female patients who underwent laparoscopic living-donor nephrectomy (n = 70) or transvaginal natural orifice transluminal endoscopic surgery–assisted living-donor nephrectomy (n = 45) were included and compared in terms of operative characteristics, as well as donor and recipient outcomes.

Results:

No significant difference was observed between the laparoscopic living-donor nephrectomy and transvaginal natural orifice transluminal endoscopic surgery–assisted living-donor nephrectomy groups in terms of mean duration of warm and cold ischemia, operation time, length of hospital stay, arterial anastomoses, visual analog scale pain scores, serum creatinine levels, and receiver outcomes, whereas a significantly higher number of venous anastomoses was noted in the laparoscopic living-donor nephrectomy group than in the transvaginal natural orifice transluminal endoscopic surgery–assisted living-donor nephrectomy group (P = .029).

Conclusions:

Transvaginal natural orifice transluminal endoscopic surgery–assisted living-donor nephrectomy seems to be a feasible and reproducible alternative to conventional laparoscopic living-donor nephrectomy in female donors provided the viability of the vagina as an organ retrieval route.  相似文献   
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OBJECTIVES: The aim of vertebral body replacement is the stabilisation and restoration of the anterior column of the spine with removal of the diseased region. We present our results of stabilisation, pain reduction and neurological improvement using vertebral-body replacement systems METHODS: Between April 1997 and December 2002, 53 patients with malignant vertebral destruction or instability due to traumatic and osteoporotic fracture were treated. We evaluated the results after vertebrectomy and vertebral body replacement by using expandable titanium cages in a retrospective study. RESULTS: The average follow-up time was 18.9 +/- 19.9 months. The mean operation time was 173.2 +/- 77.4 minutes. Intraoperatively, we saw no implant-related complications. Perioperatively, complications appeared in 18 patients (34.0 %). 4 of them were severe, with 2 patients dying. In the total follow-up, 16 patients died, 10 of them (62.5 %) due to tumour progression. Pain reduction was reported in 52.7 %, neurological improvement in 48.0 %. One patient had a loosening of his posterior instrumentation in the further follow-up due to tumour growth with dislocation of the cage and a deterioration of his neurological deficit. CONCLUSION: By using vertebral body replacement systems, sufficient stabilisation of the vertebral column, pain reduction and neurological improvement can be achieved with an acceptable perioperative risk.  相似文献   
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