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71.
The prevalence of calcified cysts and the significance of calcification as a sign of cyst inactivity in cystic echinococcosis (CE) was evaluated. Seventy-eight patients (36 females, 42 males, mean age 40.8 +/- 16.9 years) with CE, having a total of 137 abdominal cysts (116 hepatic, three splenic, one renal and 17 peritoneal cysts), were diagnosed and followed-up by ultrasound during and after albendazole treatment or as part of the watch-and-wait approach recording changes in the cyst wall and content. In 48 patients with 94 cysts, computed tomography (CT) imaging was additionally available and was correlated with ultrasound findings. Cyst wall calcification was classified into (1) "sprinkled", (2) "eggshell-like", and (3) "circular". Calcification of the cyst wall and/or cyst content was detected in 67 echinococcal cysts (48.9% of all cysts) in 39 patients (15 females, 24 males, mean age 40.8 +/- 14.8 years). Of the total of 67 calcified cysts, only 23 were compatible with WHO type CE5, 18 with WHO type CE4. Judged by cyst content, the remaining 26 were of WHO type CE1, CE2 and CE3 (n = 1, n = 8, and n = 17, respectively). During a mean period of 34.3 months (+/- 21.3 months) the majority of cysts (n = 32) did not exhibit any change in cyst content and wall properties. Fourteen cysts showed signs of progressive involution, five cysts (all of WHO type CE3) of renewed activity defined by recurring fluid collection. In 16 cysts, no follow-up was available due to surgery or drop out. Calcification of the cyst is not restricted to the inactive WHO cyst types CE4 and CE5, but occurs in all stages and in up to 50% of cysts. The completeness and, most importantly, the stability of consolidation of cyst content over time predicts cyst inactivity more reliably.  相似文献   
72.
HYPOTHESIS: Advances in specialized centers for pancreatic diseases have improved surgical morbidity and outcome. In the past, postoperative local complications (pancreatic fistulae) were causing most of the mortality. Now, more patients experience postoperative complications related to their comorbidity. DESIGN: To report a prospective audit of a single center's experience with pancreatic resection during an 8-year period. SETTING: Tertiary referral center focused on pancreatic diseases. PATIENTS AND INTERVENTIONS: Six hundred seventeen consecutive patients underwent pancreatectomy between November 1, 1993, and August 31, 2001. The series included 468 pancreatic head resections (76%), 25 total pancreatectomies (4%), 88 left-sided resections (14%), and 36 others (6%). MAIN OUTCOME MEASURES: Morbidity after pancreatic resection. RESULTS: Postoperative in-hospital mortality was 1.6%, and the additional operation rate was 4.1%. Four patients died of surgical complications and 6 of systemic complications. Systemic morbidity was 18% and consisted primarily of cardiopulmonary complications (13%). The most frequent postoperative complication was delayed gastric emptying (14%), which caused significant prolongation of the hospital stay. No patients died of a postoperative pancreatic fistula, which occurred in 3.2%, and no completion pancreatectomies were necessary. CONCLUSIONS: Pancreatic resections can be performed with considerable safety and a low rate of pancreatic complications. More patients die of systemic complications than in the past, which increases the demand for precise preoperative patient selection. Completion pancreatectomy should no longer be considered in patients with a pancreatic fistula.  相似文献   
73.

Introduction

In North Africa and the Middle East, studies about dementia prevalence are scarce. A pilot study was conducted in Lebanon to assess dementia prevalence, using the Arabic-validated 10/66 Dementia Research Group (DRG) diagnostic assessment for case ascertainment. The study also examined care arrangement and access to care.

Methods

A random sample of 502 persons older than 65 years and their informant were recruited from Beirut and Mount Lebanon governorates through multistage cluster sampling.

Results

The crude and age-standardized dementia prevalences were 7.4% and 9.0%, respectively. People with dementia were mainly cared for by relatives at home. Access to formal care was very limited.

Discussion

Dementia prevalence in Lebanon ranks high within the global range of estimates. These first evidence-based data about disease burden and barriers to care serve to raise awareness and call for social and health care reform to tackle the dementia epidemic in Lebanon and in North Africa and the Middle East.  相似文献   
74.
75.
Abstract:  Renal transplantation is accepted as the preferred treatment for most cases of end-stage renal disease. Postoperative vascular complications include stenosis or thrombosis of the transplant renal artery or arteriovenous fistulas after biopsy. Impaired arterial perfusion of the transplant may be the leading cause for graft dysfunction or refractory hypertension. Therefore, non-invasive imaging modalities are required to detect and locate vascular complications with high accuracy. Doppler ultrasound is suited as a screening method for the detection of impaired graft perfusion. Magnetic resonance imaging (MRI) is used for an accurate diagnosis of vascular complications and to support decision for appropriate surgical or interventional treatment. Minimal invasive techniques like percutaneous transluminal angioplasty and stent placement have evolved as safe procedures with a high technical success rate reducing substantial morbidity. They can be considered as an alternative to surgical treatment of transplant renal artery stenosis (TRAS). Embolization of severe arteriovenous fistulas is the method of choice if the feeding artery can be occluded through a microcatheter. In selected cases, even catheter-guided fibrinolytic treatment of arterial thrombosis might be considered, if instantaneous surgery is considered a high-risk procedure. This article reviews the imaging features of common vascular complications after renal transplantation with focus on MRI. In addition, interventional radiological techniques are described for the treatment of TRAS, acute thrombotic occlusion, and arteriovenous fistulas.  相似文献   
76.
Neurogenic factors in the impaired healing of diabetic foot ulcers   总被引:3,自引:0,他引:3  
BACKGROUND: We hypothesize that the reduced innervation of skin can be observed both in clinically neuropathic and non-neuropathic diabetic foot ulcers and can contribute to low inflammatory cell infiltration. MATERIALS AND METHODS: Twenty patients with type 2 diabetes and active foot ulcers, without clinical evidence of peripheral sensory neuropathy (n = 12) and with sensory neuropathy (n = 8) were involved in this study. Biopsies from ulcer margin were examined immunohistochemically. RESULTS: Studies revealed presence of protein gene product 9.5 (PGP9.5)+ nerve endings only in reticular dermis in 3 of 12 non-neuropathic subjects, however, regenerating GAP-43+ endings were seen in dermis of almost all specimens. Lack of substance P+ nerve endings was characteristic for both groups. The reduced distribution of calcitonin gene-related peptide+ nerves in epidermis and dermis was seen mainly in neuropathic group. In neo-epidermis lack of nerve growth factor expression was observed in both groups, whereas neurotrophin 3 immunostaining was characteristic for neuropathic specimens (P < 0.03). Expression of trkA and trkC receptors did not differ significantly between groups. Low inflammatory cell infiltration and moderate presence of fibroblasts was characteristic for all studied specimens. CONCLUSIONS: The observed reduction of foot skin innervation and neurogenic factors expression can be correlated with low inflammatory cell accumulation and subsequently leads to the observed chronicity of diabetic foot ulcer healing process in both neuropathic and non-neuropathic patients.  相似文献   
77.
Background Procalcitonin (PCT) is regarded as a specific indicator of bacterial infection. Infectious complications in patients after colorectal surgery are a common cause of morbidity and mortality. The aim of this study was to investigate (a) whether PCT could serve as a negative predictive marker for postoperative complications and (b) whether, in patients with elevated PCT levels, a pre-emptive treatment with the third-generation cephalosporin ceftriaxone is superior to an antibiotic treatment starting later on the appearance of clinical signs and symptoms of infection.Patients and methods By screening 250 patients with colorectal surgery, we identified 20 patients with PCT serum levels more than 1.5 ng/ml on at least 2 of the first 3 postoperative days. The remaining 230 patients were followed-up for the occurrence of infectious complications. The 20 patients with elevated PCT were included in a prospective randomised pilot study comparing pre-emptive antibiotic treatment with ceftriaxone vs standard treatment.Results The negative predictive value of PCT for systemic infectious complications was 98.3%. In patients receiving pre-emptive antibiotic treatment (ceftriaxone), both the incidence and the severity of postoperative systemic infections were significantly lower compared to those in a control group (Pearson’s χ 2 test; p=0.001 and p=0.007, respectively). Major differences were also observed with respect to duration of antibiotic treatment and length of hospital stay.Conclusions PCT is an early marker for systemic infectious complications after colorectal surgery with a high negative predictive value. A significant reduction in the rate of postoperative infections in patients with elevated PCT serum concentrations was achieved by means of pre-emptive antibiotic treatment.  相似文献   
78.

Background

Hard pancreas is welcome by surgeons performing resective pancreatic surgery, because it is believed to offer better suture holding capacity (SHC), thus decreasing the risk for a postoperative leak. However, neither the actual SHC of pancreatic tissue in humans nor its determinants have been studied.

Methods

We directly measured SHC for polydioxanone 5–0 suture and tissue hardness at the pancreatic isthmus in 53 human pancreata using a dynamometer and a durometer. A histologic score based on fibrosis grade, fat content, pancreatic duct size, and signs of chronic pancreatitis was calculated for every sample. We tested the hypothesis that SHC of the pancreas was proportional to tissue hardness, and evaluated the role of different possible histomorphologic determinants of SHC.

Results

Suture-holding capacity correlated perfectly with tissue hardness (r = 0.98; P < 0.001; 95% confidence interval, 0.96–0.99). The histologic score showed a stronger correlation with both parameters than any single histologic parameter. The SHC of transductal sutures was significantly higher than that of pure transparenchymal sutures. The SHC and hardness were significantly lower in patients who developed a clinically relevant pancreatic fistula postoperatively.

Conclusions

A mixture of histomorphologic features of human pancreas determines its tissue hardness and SHC. Involvement of the main pancreatic duct in the suture line appears to increase the mechanical strength of the pancreatic anastomosis.  相似文献   
79.
Clinical Oral Investigations - Nucleotide excision repair protein expression has been claimed to be responsible for platinum-based chemotherapy resistance. ERCC1, XPF and XPA, core proteins in DNA...  相似文献   
80.

Purpose

To investigate the value of 4 different protocols for prospectively triggered 256-slice coronary computed tomography angiography (coronary CTA).

Methods

Two hundred and ten patients underwent prospectively triggered coronary CTA for suspected or known coronary artery disease (CAD). Patients with heart rate >75 bps before the scan despite ß-blocker administration and with arrhythmia were excluded. From January to September 2010, 60 patients underwent coronary CTA using a non-tailored protocol (120 kV; 200 mAs) and served as our ‘control’ group. From September 2010 to April 2012, based on the body mass index (BMI) of the examined patients (BMI subgroups of < 25; 25–28; 28–30, and ≥ 30 kg/m2) current tube voltage and tube current were: (1) slightly, (2) moderately or (3) strongly reduced, resulting into the 3 following BMI-adapted acquisition groups: (1) a ‘standard’ (100/120 kV; 100–200 mAs; n = 50), 2) a ‘low dose’ (100/120 kV; 75–150 mAs; n = 50), and 3) an ‘ultra-low dose’ (100/120 kV; 50–100 mAs; n = 50) protocol.

Results

Patients examined using the non-tailored protocol exhibited the highest radiation exposure (3.2 ± 0.4 mSv), followed by the standard (1.6 ± 0.7 mSv), low-dose (1.2 ± 0.6 mSv) and ultra-low dose protocol (0.7 ± 0.3 mSv) (radiation savings of 50%, 63% and 78% respectively). Overall image quality was similar with standard dose (1.9 ± 0.6) and low-dose (2.0 ± 0.5) compared to the non-tailored group (1.9 ± 0.5) (p = NS for all). In the ultra-low dose group however, image quality was significant reduced (2.7 ± 0.6), p < 0.05 versus all other groups).

Conclusion

Using BMI-adapted low dose acquisitions image quality can be maintained with simultaneous radiation savings of ∼65% (dose of ∼1 mSv). This appears to be the lower limit for diagnostic coronary CTA, whereas ultra-low dose acquisitions result in significant image degradation.  相似文献   
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