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91.
The purpose of this study was to identify systematic reviews (SRs) that compared laser with other dental restorative procedures and to evaluate their methodological quality. A search strategy was developed and implemented for MEDLINE, the Cochrane Library, LILACS, and the Brazilian Dentistry Bibliography (1966–2007). Inclusion criteria were: the article had to be an SR (± meta-analysis); primary focus was the use of laser in restorative dentistry; published in English, Spanish, Portuguese, Italian, German. Two investigators independently selected and evaluated the SRs. The overview quality assessment questionnaire (OQAQ) was used to evaluate methodological quality, and the results were averaged. There were 145 references identified, of which seven were SRs that met the inclusion criteria (kappa?=?0.81). Of the SRs, 71.4% appraised lasers in dental caries diagnosis. The mean overall OQAQ score was 4.4 [95% confidence interval (CI) 2.4–6.5]. Of the SRs, 57.1% had major flaws, scoring ≤4. SR methodological quality is low; therefore, clinicians should critically appraise them prior to considering their recommendations to guide patient care.  相似文献   
92.
Clinical natural orifice surgery has been applied to abdominal surgery in recent years, mostly using transvaginal and transgastric access. Rectal and transcolonic natural orifice transluminal endoscopic surgery (NOTES) were tested in animal and cadaver models by a few research groups. Despite the potential advantages of transcolonic NOTES for colorectal diseases, it has not yet been clinically applied. The first successful series of human applications of transcolonic NOTES in the literature from the NOTES Research Group in Brazil provide new possibilities in the field in new transrectal procedures for rectal cancer and benign disease. Successful first human reports on Transcolonic NOTES potentially brings new frontiers and applications for minimally invasive surgery. The treatment of colorectal diseases through flexible Perirectal NOTES Access is a promising new approach alongside existing laparoscopic and open surgery to improve patient care.  相似文献   
93.
The purpose of the present study was to evaluate the sleep homeostasis of rats submitted to a protocol of chronic sleep restriction by two methods and to evaluate the sleep characteristics during the recovery period. The sleep restriction protocol was accomplished by sleep depriving rats for 18 h everyday for 21 days, using the single platform method (SPM) or the modified multiple platform method (MMPM) of paradoxical sleep (PS) deprivation. Rats were allowed to sleep for 6 h (from 10:00 to 16:00; starting 3 h after lights on) in their individual home-cages, during which their sleep was recorded. At the end of the sleep restriction protocol, rats were recorded in their home-cages for 4 days, where they could sleep freely. Both methods used to induce chronic sleep restriction were effective, in sofar as they resulted in augmented sleep time during the 6h-sleep period, with very few bouts of wakening. Although comparison between the methods did not reveal differences, sleep restriction under MMPM produced a more consistent daily rebound, mainly of paradoxical sleep, with longer episodes. These results showed distinct sleep recovery patterns, suggesting a possible role of the waking experiences (i.e. immobilization stress, social interaction) acting on sleep consolidation.  相似文献   
94.
BACKGROUND: Super-obese patients can achieve adequate weight loss with long limb Roux-en-Y gastric bypass (RYGB). These patients, however, might need longer intestinal limbs to control co-morbidities such as type 2 diabetes, lipid disorders, hypertension, sleep apnea, and gastroesophageal reflux disorder. METHODS: A total of 105 patients with a body mass index of > or =50 kg/m(2) were randomly divided into 2 similar groups regarding sex, age, and number of co-morbidities. All underwent laparoscopic Roux-en-Y gastric bypass. In group 1, the length of the biliary limb was 50 cm and the length of the Roux limb was 150 cm. In group 2, the length of the biliary limb was 100 cm and the length of the Roux limb was 250 cm. RESULTS: The follow-up for both group was 48 months. Diabetes was controlled in 58% of group 1 and in 93% of group 2 (P <0.05). Lipid disorders improved in 57% of group 1 and in 70% of group 2 (P <0.05). No statistical difference was found in the control or improvement of hypertension, sleep apnea, or gastroesophageal reflux disorder. The excess weight loss was faster in group 1 but was similar in both groups at 48 months (70% in group 1 and 74% in group 2), with no statistical difference. CONCLUSION: Patients with longer biliary and Roux limbs achieved greater type 2 diabetes control, greater lipid disorder improvement, and showed a trend toward faster excess weight loss.  相似文献   
95.
This is a comparative study between manual volumetry (MV) and voxel based morphometry (VBM) as methods of evaluating the volume of brain structures in magnetic resonance images. The volumes of the hippocampus and the amygdala of 16 panic disorder patients and 16 healthy controls measured through MV were correlated with the volumes of gray matter estimated by optimized modulated VBM. The chosen structures are composed almost exclusively of gray matter. Using a 4 mm Gaussian filter, statistically significant clusters were found bilaterally in the hippocampus and in the right amygdala in the statistical parametric map correlating with the respective manual volume. With the conventional 12 mm filter,a significant correlation was found only for the right hippocampus. Therefore, narrow filters increase the sensitivity of the correlation procedure, especially when small brain structures are analyzed. The two techniques seem to consistently measure structural volume.  相似文献   
96.
The incidence of intraoperative femoral fractures with a single design of stem implant, the Meridian (Stryker-Howmedica, Rutherford, N.J.), has been assessed in a study of 117 implants in patients treated consecutively between 1996 and 2001. The aim of the study was to evaluate the risk factors for suffering an intraoperative fracture and to determine, based on a short-term follow-up, if there were radiographic signs of early loosening. The following variables were analysed: demographic factors of the patient, morphology of the femur, intraoperative factors and postoperative radiographic factors. The radiographic stability of the implant and the presence of early signs of loosening were evaluated 2 years after surgery. The incidence of femoral fractures was 11% (13 cases in 117 implants), which is higher that reported in earlier published studies, and there was an increased number of fractures when the proximal filling of the femoral canal was higher. Although there was no statistically significant relation between the variables studied and the appearance of an intraoperative fracture, we conclude that the appearance of a femoral intraoperative fracture did not affect the radiographic stability of the implant during the short-term follow-up of our study cohort.  相似文献   
97.
98.
Traumatic brachial plexus injuries are a devastating injury that results in partial or total denervation of the muscles of the upper extremity. Treatment options that include neurolysis, nerve grafting, or neurotization (nerve transfer) has become an important procedure in the restoration of function in patients with irreparable preganglionic lesions. Restoration of elbow flexion is the primary goal in treating patients with severe brachial plexus injuries. Nerve transfers are used when spinal roots are avulsed, and proximal stumps are not available. In the present study, we analyze the results obtained in 20 patients treated with phrenic–musculocutaneous nerve transfer to restore elbow flexion after brachial plexus injuries. A consecutive series of 25 adult patients (21 men and 4 women) with a brachial plexus traction/crush lesion were treated with phrenic–musculocutaneous nerve transfer, but only 20 patients (18 men and 2 women) were followed and evaluated for at least 2 years postoperatively. All patients had been referred from other institutions. At the initial evaluation, eight patients received a diagnosis of C5-6 brachial plexus nerve injury, and in the other 12 patients, a complete brachial plexus injury was identified. Reconstruction was undertaken if no clinical or electrical evidence of biceps muscle function was seen by 3 months post injury. Functional elbow flexion was obtained in the majority of cases by phrenic–musculocutaneous nerve transfer (14/20, 70%). At the final follow-up evaluation, elbow flexion strength was a Medical Research Council Grade 5 in two patients, Grade 4 in four patients, Grade 3 in eight patients, and Grade 2 or less in six patients. Transfer involving the phrenic nerve to restore elbow flexion seems to be an appropriate approach for the treatment of brachial plexus root avulsion. Traumatic brachial plexus injury is a devastating injury that result in partial or total denervation of the muscles of the upper extremity. Treatment options include neurolysis, nerve grafting, or neurotization (nerve transfer). Neurotization is the transfer of a functional but less important nerve to a denervated more important nerve. It has become an important procedure in the restoration of function in patients with irreparable preganglionic lesions. Restoration of elbow flexion is the primary goal in treating patients with severe brachial plexus injuries. Nerve transfers are used when spinal roots are avulsed, and proximal stumps are not available. Newer extraplexal sources include the ipsilateral phrenic nerve as reported by Gu et al. (Chin Med J 103:267–270, 1990) and contralateral C7 as reported by Gu et al. (J Hand Surg [Br] 17(B):518–521, 1992) and Songcharoen et al. (J Hand Surg [Am] 26(A):1058–1064, 2001). These nerve transfers have been introduced to expand on the limited donors. The phrenic nerve and its anatomic position directly within the surgical field makes it a tempting source for nerve transfer. Although not always, in cases of complete brachial plexus avulsion, the phrenic nerve is functioning as a result of its C3 and C4 major contributions. In the present study, we analyze the results obtained in 20 patients treated with phrenic–musculocutaneous nerve transfer to restore elbow flexion after brachial plexus injuries.  相似文献   
99.
The expanded endonasal approach provides access to the entire ventral skull base for resection of neoplasms involving the skull base and brain. The creation of large defects of the bone and dura endoscopically presents unique reconstructive challenges. A layered reconstruction of the dura with inlay and onlay fascial grafts covered with fat grafts is an effective technique for repair. An intranasal balloon catheter is used to provide counterpressure in the early phase of healing and a lumbar spinal drain is a useful adjunct in patients at increased risk of a cerebrospinal fluid leak. Vascularized flaps may be necessary in some patients receiving radiation therapy. Continued advances in surgical technology and the introduction of new biomaterials will facilitate the reconstruction of skull base defects following endonasal brain surgery.  相似文献   
100.
To examine the apoptosis expression in the intestinal mucosa in accordance of different periods of hyperbaric oxygen (HBO) treatment, rats were submitted to 60 min of mesenteric artery and vein ischemia and 60 min of reperfusion occlusion. A group (G-IR) was the control and HBO was applied in the ischemia (GHBO-I), reperfusion (GHBO-R), and ischemia and reperfusion time (GHBO-IR). After 60 min of reperfusion, samples of small bowel were prepared for immunohistochemical expression of caspase-3. The expression of caspase-3 was significantly inferior when HBO was administered in the ischemia (0.16 +/- 0.01) in comparison with the control (0.70 +/- 0.08), but HBO in the further reperfusion (0.84 +/- 0.03) or both ischemia and reperfusion time (0.42 +/- 0.05) was significantly worse. There was a connection between HBO, small bowel I/R injury, and mucosa apoptosis. The favorable effect was obtained when HBO was administered early in the ischemia time.  相似文献   
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