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71.
The aim of this trial was to investigate changes occurring in the subgingival microbiological composition of subjects with aggressive periodontitis, treated with antimicrobial photodynamic therapy (aPDT), in a single episode, or scaling and root planing (SRP), in a split-mouth design on −7, 0, and +90 days. Ten patients were randomly assigned to either aPDT using a laser source in conjunction with a photosensitizer or SRP with hand instruments. Subgingival plaque samples were collected and the counts of 40 subgingival species were determined using checkerboard DNA-DNA hybridization. The data were analyzed using the method of generalized estimating equations (GEE) to test the associations between treatments, evaluated parameters, and experimental times (α = .05). The results indicated that aPDT and SRP affects different bacterial species, with aPDT being effective in reducing numbers of A. actinomycetemcomitans than SRP. On the other hand, SRP was more efficient than aPDT in reducing the presence of periodontal pathogens of the Red Complex. Additionally, a recolonization in the sites treated by aPDT was observed, especially for T. forsythia and P. gingivalis. Under our experimental conditions, this trial demonstrates that aPDT and SRP affected different groups of bacteria, suggesting that their association may be beneficial for the non-surgical treatment of aggressive periodontitis.  相似文献   
72.
The purposes of this study were to photoelastically measure the biomechanical behavior of 4 implants retaining different cantilevered bar mandibular overdenture designs and to compare a fixed partial denture (FPD). A photoelastic model of a human edentulous mandible was fabricated, which contained 4 screw-type implants (3.75 × 10 mm) embedded in the parasymphyseal area. An FPD and 3 overdenture designs with the following attachments were evaluated: 3 plastic Hader clips, 1 Hader clip with 2 posterior resilient cap attachments, and 3 ball/O-ring attachments. Vertical occlusal forces of 100 N were applied between the central incisor and unilaterally to the right and left second premolars and second molars. Stresses that developed in the supporting structure were monitored photoelastically and recorded photographically. The results showed that the anterior loading, the overdenture with 3 plastic Hader clips, displayed the largest stress concentration at the medium implant. With premolar loading, the FPD and overdenture with 3 plastic Hader clips displayed the highest stresses to the ipsilateral terminal implant. With molar loading, the overdenture with 3 ball/O-ring attachments displayed the most uniform stress distribution in the posterior edentulous ridge, with less overloading in the terminal implant. It was concluded that vertical forces applied to the bar-clip overdenture and FPD created immediate stress patterns of greater magnitude and concentration on the ipsilateral implants, whereas the ball/O-ring attachments transferred minimal stress to the implants. The increased cantilever in the FPD caused the highest stresses to the terminal implant.  相似文献   
73.
ObjectivesTo determine the effect of ion exchange on slow crack growth (SCG) parameters (n, stress corrosion susceptibility coefficient, and σf0, scaling parameter) and Weibull parameters (m, Weibull modulus, and σ0, characteristic strength) of a dental porcelain.Methods160 porcelain discs were fabricated according to manufacturer's instructions, polished through 1 μm and divided into two groups: GC (control) and GI (submitted to an ion exchange procedure using a KNO3 paste at 470 °C for 15 min). SCG parameters were determined by biaxial flexural strength test in artificial saliva at 37 °C using five constant stress rates (n = 10). 20 specimens of each group were tested at 1 MPa/s to determine Weibull parameters. The SPT diagram was constructed using the least-squares fit of the strength data versus probability of failure.ResultsMean values of m and σ0 (95% confidence interval), n and σf0 (standard deviation) were, respectively: 13.8 (10.1 ? 18.8) and 60.4 (58.5 ? 62.2), 24.1 (2.5) and 58.1 (0.01) for GC and 7.4 (5.3 ? 10.0) and 136.8 (129.1 ? 144.7), 36.7 (7.3) and 127.9 (0.01) for GI. Fracture stresses (MPa) calculated using the SPT diagram for lifetimes of 1 day, 1 year and 10 years (at a 5% failure probability) were, respectively, 31.8, 24.9 and 22.7 for GC and 71.2, 60.6 and 56.9 for GI.SignificanceFor the porcelain tested, the ion exchange process improved strength and resistance to SCG, however, the material's reliability decreased. The predicted fracture stress at 5% failure probability for a lifetime of 10 years was also higher for the ion treated group.  相似文献   
74.
Summary Adriamycin (ADM) is an effective antineoplastic drug. However, the amount of ADM that can be administered must be limited because of the risk of developing a severe dose-dependent cardiomyopathy. 4Epi-adriamycin (4 ADM) is a new anthracycline analog with similar antineoplastic properties as ADM, but with perhaps less cardiac toxicity. To determine myocardial performance after a chronic treatment with 4ADM, we studied 17 patients (mean age 36.6 years) suffering from lymphomas by means of 24-hour ambulatory ECG, x-ray, M-mode echocardiogram, and rest-exercise gated radionuclide ventriculography (RNV), performed prior to and 2 months after the end of the treatment. Pretreatment and post-treatment shortening fractions, basal pretreatment and post-treatment ejection fractions, and postexercise pretreatment and post-treatment ejection fractions, were tested for correlation with individual 4ADM doses and pretreatment with ADM. No association was noted among them, showing the lack of correlation between doses and impairment of ventricular performance. 4ADM doses ranged from 400 to 1100, 748±174 mg/m2; allnoninvasive studies including RNV doses and RNV (Pearson's correlation coefficient, p=ns). No deterioration of ventricular performance could be demonstrated. Conversely, the basal pretreatment ejection fraction changed from 56.17±7.6% to 61.52±8.3% in posttreatment (p<0.0001). Surprisingly, the postexercise pretreatment ejection fraction also increased from 55.47±7.7% to 63.35±10% in post-treatment (p<0.03). The shortening fraction changed from 35.47±4.8% to 36.47±4.2% after 4ADM treatment (ns). No impairment of cardiac function could be shown in patients previously treated with ADM or radiotherapy. On the basis of these data, treatment with 4ADM did not impair but improved cardiac function  相似文献   
75.
Porcine deltacoronavirus has caused great economic losses in the swine industry worldwide. In this study, we carried out the first detection, sequencing and characterization of this virus in Mexico. We analysed 885 rectal samples by multiplex RT‐PCR to determine coinfections. In addition, the Spike gene was amplified, sequenced and analysed phylogenetically. We found 85 positive samples for porcine deltacoronavirus, representing 9.6% of the total samples, and we determined that the most frequent coinfection was with porcine epidemic diarrhoea virus (54.1%). Four sequences of Mexican isolates were most closely related to those of the United States. The antigenic regions and the glycosylation site of the strains obtained coincide with those previously reported. This relationship is probably related to the commercial exchange of pigs between the US and Mexico and the geographical proximity of these two countries.  相似文献   
76.
OBJECTIVES: Bacillus Calmette-Guérin (BCG) has proven its efficacy in the treatment of carcinoma in situ (CIS) of the prostatic urethra. We performed a retrospective study to evaluate the use of intravesical instillations of BCG in patients with carcinoma in situ involving prostatic ducts after complete transurethral resection (TUR). MATERIAL AND METHODS: Eligibility for the study was CIS of the prostatic urethra involving prostatic ducts. Previous instillation with BCG was an exclusion criterion. Patients were treated with intravesical BCG Connaught (81 mg) administered once a week, over a 6-wk period. TUR loop biopsies of the prostate were performed only when a macroscopic tumor was present. RESULTS: In this retrospective study of 11 patients, 8 (73%) presented with macroscopic tumor in the prostatic urethra. Ten patients (91%) had a simultaneous superficial bladder carcinoma. Eight patients (73%) had tumoral involvement of the bladder neck region. After a median follow-up of 27 mo (n=10 patients), the response in the prostatic urethra was 82%, and the response in the bladder due to superficial tumor recurrence was 64%. Two patients with residual ductal disease in the prostatic urethra were subsequently treated with cystoprostatectomy and are currently free of disease. In one of those patients, the cystoprostatectomy specimen did show prostatic stromal invasion. Another patient developed distant metastatic disease and died a few months after diagnosis. Thus, progression was encountered in two patients (18%). Currently, 90% of patients are alive without evidence of disease and 72.7% have benefitted from this bladder preservation strategy. CONCLUSION: Intravesical BCG is a feasible treatment option for patients with CIS involving prostatic ducts. In this retrospective study, bladder preservation was successful in 8 of 11 patients (70%) and there was only one oncologic death. Obviously, these patients need a careful follow-up with cystoscopy and cytology to detect either recurrence or progression and in those with persistent disease after the initial BCG induction therapy, prompt cystectomy is indicated.  相似文献   
77.

Introduction

Treatment of oesophageal cancer with curative intent requires a multidisciplinary approach. Neoadjuvant therapy, the radicality of resection and extension of lymphadenectomy have been associated with increased operative morbidity and mortality. The aim of this study was to assess the results of surgical treatment of oesophageal cancer since the presence of an interdisciplinary esophagogastric tumour board.

Methods

Patients with cancer of the oesophagus and oesophagogastric junction who underwent oesophagectomy between January 2005 and March 2012 were included in this retrospective study. Data concerning type of resection, postoperative complications, mortality and survival were analysed.

Results

Of the 392 patients with a diagnosis of oesophageal cancer over the study period, 100 underwent oesophagectomy. Seventy-four patients received neoadjuvant treatment. Eighty-two patients underwent transthoracic resection while a transhiatal was used in 10 patients. Colon interposition was required in 8 cases. An R0 resection was achieved in 98 patients. Anastomotic leaks developed in 15 patients, 9 were intrathoracic and 6 were cervical. Postoperative morbidity occurred in 42% of patients, and intra-hospital and 90-day mortality was 2%. Median length of hospital stay was 16 days. The respective actuarial survival at 1 and 5 years were 82% and 56%.

Conclusions

Surgical treatment with curative intention for oesophageal cancer is only possible in a quarter of patients diagnosed. The high morbidity rate was mainly due to intrathoracic complications.  相似文献   
78.
79.
The aim of this study was to provide a systematic review and meta‐analysis of reports comparing laparoendoscopic single‐site (LESS) living‐donor nephrectomy (LDN) vs standard laparoscopic LDN (LLDN). A systematic review of the literature was performed in September 2013 using PubMed, Scopus, Ovid and The Cochrane library databases. Article selection proceeded according to the search strategy based on Preferred Reporting Items for Systematic Reviews and Meta‐analyses criteria. Weighted mean differences (WMDs) were used to measure continuous variables and odds ratios (ORs) to measure categorical ones. Nine publications meeting eligibility criteria were identified, including 461 LESS LDN and 1006 LLDN cases. There were more left‐side cases in the LESS LDN group (96.5% vs 88.6%, P < 0.001). Meta‐analysis of extractable data showed that LLDN had a shorter operative time (WMD 15.06 min, 95% confidence interval [CI] 4.9–25.1; P = 0.003), without a significant difference in warm ischaemia time (WMD 0.41 min, 95% CI –0.02 to 0.84; P = 0.06). Estimated blood loss was lower for LESS LDN (WMD ?22.09 mL, 95% CI –29.5 to –14.6; P < 0.001); however, this difference was not clinically significant. There was a greater likelihood of conversion for LESS LDN (OR 13.21, 95% CI 4.65–37.53; P < 0.001). Hospital stay was similar (WMD –0.11 days, 95% CI –0.33 to 0.12; P = 0.35), as well as the visual analogue pain score at discharge (WMD –0.31, 95% CI –0.96 to 0.35; P = 0.36), but the analgesic requirement was lower for LESS LDN (WMD –2.58 mg, 95% CI –5.01 to –0.15; P = 0.04). Moreover, there was no difference in the postoperative complication rate (OR 1.00, 95% CI 0.65–1.54; P = 0.99). Renal function of the recipient, as based on creatinine levels at 1 month, showed similar outcomes between groups (WMD 0.10 mg/dL, –0.09 to 0.29; P = 0.29). In conclusion, LESS LDN represents an emerging option for living kidney donation. This procedure offers comparable surgical and early functional outcomes to the conventional LLDN, with a lower analgesic requirement. However, it is more technically challenging than LLDN, as shown by a greater likelihood of conversion. The role of LESS LDN remains to be defined.  相似文献   
80.
BackgroundPenile prostheses are the third option in the treatment of erectile dysfunction, however, despite their proven effectiveness, the occurrence of infections, advanced age of patients and comorbidities are the main limiting factors for this treatment modality. In the continuous search for biointegrated, clinically durable and minimally invasive treatment options, a possible model of penile prosthesis was sought through the use of intracavernous bacterial cellulose (BC) gel, in an experimental model of orchiectomized rabbits.MethodsThirty adult New Zealand rabbits were equally distributed into three groups: BC; vehicle and control. Each group was then subdivided according to the follow-up time of 3 and 6 months. Bilateral orchiectomy was performed 3 weeks before injection in the BC and vehicle groups. Pachymetry measurements of the penile axis, diameter and length were performed in situ. Histomorphometry analyzes of the corpora cavernosa (CC), thickness of the tunica albuginea, cell density, collagen and elastic fibers post-injection were also performed, in addition to immunohistochemistry for newly formed vessels.ResultsThe implant of BC increased both the length and thickness of the penis three and six months after the last injection, with a consequent increase in the diameter of the CC. On the other hand, the filling effect was not observed in the control and vehicle groups, confirming the degradation of this tissue after orchiectomy and the effectiveness of BC as a filling agent. Histomorphometry analyzes corroborate the mass effect of BC integrated into the tissue, permeated by predominantly lymphomononuclear inflammatory infiltrate, multinucleated giant foreign body cells, fibroblasts, elastic fibers and newly formed vessels, without degradation or loss of volume, even after six months of implantation.ConclusionsBiocompatibility and biointegration to the host tissue make BC a prosperous penile filling material, with local application and minimally invasive.  相似文献   
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