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1.
Background: There is limited information regarding the effect of grafting of the osteotomy after subcrestal implant placement. The primary aim of this study is to retrospectively evaluate the effect of bone grafting of the defect between the bone crest and the coronal aspect of implants with reduced abutment diameter placed non‐submerged and at subcrestal positions. Methods: Records of 50 consecutive patients treated with subcrestally placed dental implants grafted with a xenograft (Group A) and 50 consecutive patients with subcrestally placed dental implants without any grafting material (Group B) were reviewed. For each implant, the radiographs after placement were compared to images from the last follow‐up visit and evaluated regarding the following: 1) degree of subcrestal positioning of the implant, 2) changes of marginal hard‐tissue height over time, and 3) whether marginal hard‐tissue could be detected on the implant platform at the follow‐up visit. Results: The mean marginal loss of hard tissues was 0.11 ± 0.30 mm for Group A and 0.08 ± 0.22 mm for Group B. Sixty‐nine percent of the implants in Group A and 77% of the implants in Group B demonstrated hard tissue on the implant platform. There were no statistically significant differences between the groups regarding marginal peri‐implant hard‐tissue loss. Conclusion: The present study fails to demonstrate that grafting of the remaining osseous wound defect between the bone crest and the coronal aspect of the implant has a positive effect on marginal peri‐implant hard‐tissue changes.  相似文献   
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BACKGROUND: Controversy exists regarding inhibition of ischemic preconditioning in hyperlipidemic animals. In this study, we tested the hypothesis that hyperlipidemia inhibits the normal reduction of myocardial ischemia on repeated balloon inflations (BIs) during angioplasty. METHODS: We studied 33 patients undergoing coronary angioplasty. All underwent a minimum of three BIs. Patients were grouped according to the following plasma cholesterol levels: 13 patients had total cholesterol levels < 200 mg/dL (the normal cholesterol group); and 20 patients had total cholesterol levels > or = 200 mg/dL (the elevated cholesterol group). Surface ST-segment elevations were recorded at the end of each BI. RESULTS: In the normal cholesterol group, the mean (+/- SD) ST-segment elevation decreased from 0.21 +/- 0.15 mV during the first BI to 0.11 +/- 0.11 mV during the third BI (p < 0.05). In the elevated cholesterol group, the respective decrease was from 0.18 +/- 0.16 to 0.14 +/- 0.15 mV (p = not significant) [between-group comparisons: F = 3.97; p = 0.02]. The decrease in ST-segment elevation was correlated with the total cholesterol levels (r = -0.48; p = 0.005), the low-density lipoprotein (LDL) cholesterol levels (r = -0.50; p = 0.003), and the high-density lipoprotein/LDL levels (r = 0.44; p = 0.01). CONCLUSION: Hyperlipidemia prevents the normal reduction of myocardial ischemia on repeated BIs during angioplasty. This leads to the clinical implication that reduction of cholesterol plasma levels, apart from its other known benefits, could also have a beneficial effect on cardioprotection.  相似文献   
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BACKGROUND & AIMS: Helicobacter pylori cag(+) strains and high-expression host interleukin 1beta (IL-1beta) polymorphisms augment the risk for intestinal-type gastric adenocarcinoma, a malignancy that predominates in males. We examined the effects of an H. pylori cancer-associated determinant (cagE), IL-1beta, and host gender in a transgenic hypergastrinemic (INS-GAS) murine model of gastric carcinogenesis. METHODS: Male and female INS-GAS mice infected with wild-type H. pylori, an H. pylori cagE(-) mutant, or H. felis were killed 2-24 weeks postchallenge. Gastric injury was scored from 0 to 4, and mucosal IL-1beta levels were quantified by ELISA. RESULTS: Male INS-GAS mice infected with H. pylori uniformly developed atrophy, intestinal metaplasia, and dysplasia by 6 weeks and carcinoma by 24 weeks. Mucosal IL-1beta concentrations increased 12 weeks following Helicobacter challenge, but levels then decreased by 24 weeks. Inactivation of cagE delayed the progression to carcinoma, but neoplasia ultimately developed in all males infected with the H. pylori mutant. In contrast, none of the H. pylori-infected female mice developed cancer, and injury scores, but not IL-1beta levels, were significantly higher in males compared with females. CONCLUSIONS: H. pylori infection induces gastric adenocarcinoma in an experimental mouse model of disease. Cancer is restricted to males and loss of cagE temporally retards but does not abrogate pathologic progression. Mucosal levels of IL-1beta increase prior to the development of gastric cancer but are not related to gender. The INS-GAS model is effective for investigating discrete host-microbial interactions that culminate in gastric cancer within the context of biologic conditions induced by H. pylori.  相似文献   
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Purpose

To describe certain anatomical variations of the foramen transversarium, in spine cervical vertebrae in a contemporary specimen of an Indo-European population and approach their clinical importance during cervical spine surgery.

Methods

102 cervical vertebrae (C2–C7) from 17 different skeletons, intact without any degenerative or traumatic disorders, which belonged to the collection of the Department of Anatomy, were examined. The age of specimens at the time of their death was between 25 and 65 years. All foramina were measured with a digital caliper.

Results

The average size of the normal foramina was: 6.49 mm × 5.74 mm on the right side and 6.65 mm × 5.76 mm on the left side. Regarding the variations, we found two cervical vertebrae (1.96 %), one C3 and one C6, in which the right foramen transversarium is clearly smaller than the left. The exact dimensions of these foramina are: 2.3 mm × 2.5 mm on the right side and 6.54 mm × 8 mm on the left side in the first vertebra and 2.8 mm × 3.74 mm on the right side and 6 mm × 7.5 mm on the left side, in the second one. We also observed double foramina in 14 vertebrae (13.72 %). In seven vertebrae, the duplication was bilateral (6.86 %). We finally found one vertebra (0.98 %) with triplication of the foramen transversarium on the left side.

Conclusions

Summarizing, 10 out of our 17 skeletons were presented with variations (extremely narrow or multiple foramina). This finding of hypoplastic, duplicated and triplicated foramina transversaria in unexpectedly high rates raises questions about the integrity of the contained structures, the possibility of a different path for them. These variations may induce an extra-osseous position of the vertebra artery, and the ignorance of such an event may have catastrophic consequences during a surgery in the cervical spine.

  相似文献   
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Neurosurgical Review - Extracranial internal carotid artery dissection (ICAD) is a potential source of morbidity and mortality in trauma patients and requires high degree of suspicion for diagnosis...  相似文献   
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BACKGROUND: Clinical tests used for the detection of meniscal tears in the knee do not present acceptable diagnostic sensitivity and specificity values. Diagnostic accuracy is improved by arthroscopic evaluation or magnetic resonance imaging studies. The objective of this study was to evaluate the diagnostic accuracy of a new dynamic clinical examination test for the detection of meniscal tears. METHODS: Two hundred and thirteen symptomatic patients with knee injuries who were examined clinically, had magnetic resonance imaging studies performed, and underwent arthroscopic surgery and 197 asymptomatic volunteers who were examined clinically and had magnetic resonance imaging studies done of their normal knees were included in this study. For clinical examination, the medial and lateral joint-line tenderness test, the McMurray test, the Apley compression and distraction test, the Thessaly test at 5 degrees of knee flexion, and the Thessaly test at 20 degrees of knee flexion were used. For all clinical tests, the sensitivity, specificity, false-positive, false-negative, and diagnostic accuracy rates were calculated and compared with the arthroscopic and magnetic resonance imaging data for the test subjects and the magnetic resonance imaging data for the control population. RESULTS: The Thessaly test at 20 degrees of knee flexion had a high diagnostic accuracy rate of 94% in the detection of tears of the medial meniscus and 96% in the detection of tears of the lateral meniscus, and it had a low rate of false-positive and false-negative recordings. Other traditional clinical examination tests, with the exception of joint-line tenderness, which presented a diagnostic accuracy rate of 89% in the detection of lateral meniscal tears, showed inferior rates. CONCLUSIONS: The Thessaly test at 20 degrees of knee flexion can be used effectively as a first-line clinical screening test for meniscal tears, reducing the need for and the cost of modern magnetic resonance imaging methods.  相似文献   
8.
The purpose of this study is to present the 20-year outcome of 206 Charnley low-friction arthroplasties done by the same surgeon on 181 patients who were separated into two age groups (younger and older). In Group A (76 patients, 92 hips) the mean age at surgery was 44 years (range, 24-55 years), and in Group B (105 patients, 114 hips) the mean age at surgery was 65 years (range, 56-82 years). All patients were evaluated clinically and radiographically. At final followup, 71 patients (87 hips) in Group A and 90 patients (99 hips) in Group B were available for study. The overall failure rate for the hips of Group A was 37.9%, and the overall failure rate for the hips of Group B was 20%. The main cause of failure in Group A was aseptic loosening of the components and breakage of the femoral stem, whereas in Group B the main cause of failure was deep infection. We concluded that by eliminating the above factors, and using new cementing techniques and improved implants, the 20-year results of this arthroplasty would be better. Our results show that the Charnley arthroplasty is a reliable procedure for hip replacement, even in younger patients.  相似文献   
9.
Purpose Bile duct injury (BDI) represents the most serious complication of laparoscopic cholecystectomy (LC). The aim of this retrospective single-institution study was to evaluate the real incidence of BDI during laparoscopic and open cholecystectomy (OC) in a tertiary academic center in Athens, Greece.Methods Between January 1991 and December 2001, 3 637 patients underwent cholecystectomy in our department; as LC in 2 079 patients (LC group) and as OC in 1 558 patients (OC group). All the LCs were performed or supervised by five staff surgeons and all the OCs were performed or supervised by another five staff surgeons.Results There were 13 BDIs associated with LC (0.62%) and 6 associated with OC (0.38%) (P = 0.317). There was one death associated with BDI after LC. Only two (15.4%) of the BDIs associated with LC occurred within the proposed learning curve limit of 50 LCs per individual surgeon.Conclusion Laparoscopic cholecystectomy is safe and is not associated with a higher incidence of BDI than OC. Moreover, we did not find that the learning curve for LC affected BDI occurrence.  相似文献   
10.
Total hip arthroplasty for congenital hip disease   总被引:15,自引:0,他引:15  
BACKGROUND: It is generally agreed that the clinical and radiographic results of total hip replacement performed for degenerative arthritis secondary to congenital hip disease vary depending on the severity of the anatomical abnormality. In this study, we report the mid-term and long-term clinical and radiographic results of total hip arthroplasty performed for each of the three different types of congenital hip disease. METHODS: Between 1976 and 1994, the senior author performed 229 consecutive primary total hip arthroplasties in 168 patients with osteoarthritis secondary to congenital hip disease. Seventy-six hips were dysplastic, sixty-nine had a low dislocation, and eighty-four had a high dislocation. The Charnley low-friction technique was performed in 178 hips, and the so-called hybrid technique was performed in forty-six hips. Cementless arthroplasty was used in only five hips. RESULTS: After a minimum of seven years of follow-up, the rates of revision of the acetabular components were 15% in the dysplastic hips, 21% in the hips with a low dislocation, and 14% in those with a high dislocation. The rates of revision of the femoral components were 14%, 14%, and 16%, respectively. Survivorship analysis predicted an overall rate of prosthetic survival at fifteen years of 88.8% +/- 4.8% in the dysplastic hips, 73.9% +/- 7.2% in the hips with a low dislocation, and 76.4% +/- 8.1% in those with a high dislocation. CONCLUSIONS: An understanding of the anatomical abnormalities and the use of appropriate techniques and implants make total hip arthroplasty feasible for treatment of the three types of congenital hip disease. In patients with a low dislocation, the major technical problem is reconstruction of the natural acetabulum. In those with a high dislocation, the challenge is to place the acetabular component inside the reconstructed true acetabulum and to use an appropriate femoral implant in the hypoplastic narrow femoral diaphysis.  相似文献   
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