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1.
Laparoscopic surgery has several advantages over traditional surgery because it has been shown to be less invasive. The next logical step in the evolution of minimally invasive surgery may be to eliminate all abdominal incisions. The natural orifices provide a port of entry via the gastrointestinal tract to the peritoneal cavity. This approach would require the creation of a perforation, which is considered to be a major complication of endoscopy with significant morbidity and mortality. However, there are several recent studies that have described the technical feasibility and safety of a per‐oral transgastric approach to the peritoneal cavity using conventional endoscopes. Theoretically, this approach could reduce postoperative abdominal wall pain, wound infection, hernia formation, and adhesions. This article aims to summarize the current status of transgastric surgery, currently referred to as natural orifice transluminal endoscopic surgery (NOTES), and to address some of its future challenges.  相似文献   
2.
Abstract: The plasma ratio of each neutral amino acid (tryptophan (TRP), tyrosine (TYR), valine, isoleucine, leucine (LEU) or phenylalanine) to the sum of the other neutral amino acids was measured in 16 : manic and 14 : depressed patients. In the manics, there was a correlation between the psychomotor activity and the plasma TRP and LEU ratios. In the depressives, the depressed mood, retardation and global severity were correlated with the TRP ratio. The zotepine responders showed an increase in the TRP ratio after treatment. In the mianserin responders, the TYR ratio, which was high before the treatment, decreased to the normal range after the treatment. But, the plasma amino acid ratios remained unchanged in the patients treated with lithium carbonate or amitriptyhe. These results suggest that, in manic-depressive illness, there might be abnormalities in the metabolism of neutral amino acids, mainly of TRP and TYR, and that the plasma TRP and TYR ratios might be important indicators for determining the efflcacy of some drugs.  相似文献   
3.
The development of more complex and diverse hunting weapons may result in an increase of uncommon forms of penetrating injury to the brain. We present a case of non-fatal transorbital arrow injury to the brain. High velocity projectile injuries merit certain management adaptations from gunshot or low velocity stab wounds. This case highlights the necessity for anterograde removal of the arrow in the direction of its line of trajectory. Early assessment of the patient with cerebral angiography to identify surgically correctable vascular injury is recommended.  相似文献   
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Objective Some conditions, previously managed by general surgeons, may be treated more successfully by colorectal specialists. This argument is well established for rectal cancer but does it also apply to benign conditions? This study compares the treatment strategies and outcomes for fistulae‐in‐ano by general and colorectal surgeons in a district general hospital. Method Patients who had surgery for fistula‐in‐ano from January 1992–October 2003 were identified from theatre records. Case notes were reviewed for data on type of fistula, aetiology, surgery performed and recurrence. All patients were sent a questionnaire requesting details of recurrence and incontinence. The severity of incontinence was assessed using the Faecal Incontinence Quality of Life Scale (FIQOLS) and the Faecal Incontinence Severity Index (FISI). Results Eighty four patients (male = 53) were identified. Colorectal surgeons performed surgery in 34 and general surgeons in 50 patients. These groups were comparable with terms of age, gender, aetiology (colorectal: IBD = 5, cryptoglandular = 21: general IBD = 14, cryptoglandular = 24; P = 0.28; Chi‐squared test), and type of fistulae (colorectal: inter‐sphincteric = 20, trans‐sphincteric = 13: general inter‐sphincteric = 30, trans‐sphincteric = 18: P = 1.0; Fisher's exact test). Colorectal surgeons carried out fewer fistulotomies (47.1%vs 84.0%; P < 0.001; Fisher's exact test), more staged fistulotomies with Setons (44.1%vs 10.0%: P < 0.001; Fisher's exact test), and had fewer recurrences (9.7%vs 30.0%: P < 0.05; Fisher's exact test) when compared with general surgeons. Five patients with recurrence from the general surgery group were subsequently referred to the colorectal surgeons; four patients had further surgery (fistulotomy = 2; staged fistulotomy = 2) with no recurrence to date; one patient required proctectomy. Forty seven (64.4%) patients answered the questionnaire. There was no difference between patients operated on by colorectal or general surgeons with regards the frequency (43.5%vs 62.5%: P = 0.25; Fisher's exact test) or severity [FISI 26 (21–38); median (inter‐quartile range) vs 26 (17–38); median (inter‐quartile range: P = 0.85; Mann–Whitney test) of faecal incontinence. There was no difference between the groups with regards any of the four scales that comprised the FIQOLS. Conclusions The number of included patients is far too low to draw any conclusions but there were some interesting trends. For similar patient samples, colorectal surgeons seem to adopt a more conservative approach and have fewer recurrences than general surgeons. These differences are not reflected in the frequency or severity of postoperative incontinence.  相似文献   
6.
Alloys based on Ni–Ti intermetallics generally exhibit special shape memory and pseudoelastic properties, which make them desirable for use in the dental field as orthodontic wires. The possibility of nickel release from these materials is of high concern, because the allergenicity of this element. The aim of this study was to test pseudoelastic Ni–Ti wires in simulated physiological conditions, investigating the combined effect of strain and fluoridated media: the wires were examined both under strained (5% tensile strain) and unstrained conditions, in fluoridated artificial saliva at 37 °C. Real time electrochemical nickel release testing was performed using a novel application of a radiotracer based method, thin layer activation (TLA). TLA was validated, in unstrained conditions, against adsorptive stripping voltammetry methodology. Control tests were also performed in non-fluoridated artificial saliva. From our research it transpired that the corrosion behaviour of Ni–Ti alloy is highly affected by the fluoride content, showing a release of 4.79 ± 0.10 μg/cm2/day, but, differently from other biomaterials, it does not seem to be affected by elastic tensile strain. The application of the TLA method in the biomedical field appears a suitable technique to monitor in real time the corrosion behaviour of biomedical devices.  相似文献   
7.
Phosphorylation of proteins on tyrosine residues during activation was studied in CD3+ CEM T cells. Crosslinking of either CD4 alone or CD3/Ti alone induced weak and transient responses, but the patterns of induced tyrosine-phosphorylated proteins were different. A synergistic but still transient response occurred by the specific interaction of CD4 with CD3/Ti, whereas simultaneous but separate ligation of CD3/Ti and CD4 decreased rather than increased tyrosine phosphorylation of proteins in comparison to CD3/Ti stimulation alone. Stimulation of T cells with immobilized anti-CD3 induced strong and prolonged tyrosine phosphorylation of distinct substrates. CD4 therefore regulates protein tyrosine kinase activation by specific interaction with CD3/Ti, whereas immobilized anti-CD3 may differ from anti-CD3 in solution in the activation of protein tyrosine phosphatase(s) such as CD45.  相似文献   
8.
ObjectivesOn January 1, 2020, the Government of Ontario passed a regulation banning vaping advertisements by retailers, apart from specialty shops. A motivation for this ban was to limit youth exposure to vaping advertisements. The primary goal of this research was to evaluate the impact of this ban on the number and density of vaping advertisements surrounding secondary schools. Additionally, we examined whether the number of vaping advertisements varied by school socio-demographic characteristics.MethodsThis study used a pre-post design. Audits were conducted December 2019 (pre-ban) and again January to February 2020 (post-ban), to identify vaping advertisements within 800 m surrounding secondary schools (n = 18) in London, Ontario.ResultsPrior to the ban, there were 266 vaping advertisements within 800 m of secondary schools. After the ban, this was reduced to 58, a 78.2% reduction. The mean number of vaping advertisements surrounding schools significantly decreased from 18.1 before the ban to 3.6 after the ban (p < 0.001). A significant positive correlation was found, prior to the ban, between the number of vaping advertisements surrounding schools and school-level residential instability (r = 0.42, p = 0.02). After the ban, no significant correlations were found between the number of vaping advertisements and school socio-demographic characteristics.ConclusionThe provincial ban of vaping advertisements in select retail settings significantly reduced the number of vaping advertisements in the areas surrounding secondary schools in London, Ontario. The ban also reduced socio-demographic inequities in youths’ potential exposure to marketing of vaping products. Continued monitoring of the geographic accessibility and promotion of vaping products is warranted.  相似文献   
9.
OBJECTIVE: To determine the effectiveness of a new reflex cough test, using nebulized tartaric acid, in the evaluation of the laryngeal cough reflex and the development of aspiration pneumonia. STUDY DESIGN: In this two-phase study, the cough test assessed the cough reflex in 161 stroke subjects. Phase 1 was a double-blinded prospective study of 40 subjects scheduled to have both modified barium swallow and the reflex cough test. Phase 1 subjects with an abnormal cough test showed an increased pneumonia incidence, and therefore, phase 2 was not blinded. In phase 2, 121 subjects were evaluated using the cough test; 38 received a modified barium swallow. Test results were compared using the Fisher exact test. RESULTS: A total of 131 subjects from both phases had a normal reflex cough test; none developed pneumonia (p < .01). Thirty subjects from both phases had abnormal reflex cough test results; 5 developed pneumonia. Modified barium swallow findings did not reliably indicate the risk for developing pneumonia. Specificity of a normal reflex cough test was 100%. CONCLUSION: The reflex cough test reliably evaluated the laryngeal cough reflex and the associated risk of developing aspiration pneumonia in stroke patients. Testing the laryngeal cough reflex may significantly reduce morbidity, mortality, and costs in stroke patients.  相似文献   
10.
The effect of β( 2)-adrenoceptor antagonism in acute anxiety neurosis was investigated by comparing the effects of ICI 118,551, a specific β(2)-adrenoceptor antagonist, diazepam and placebo in a double-blind, parallel group study. Sixty-three patients, who fulfilled criteria for Anxiety Disorder (DSM III) and were psychotropic drug- free (apart from six using hypnotics), were entered. Anxiety symptoms were rated using the Hamilton Anxiety Scale (HAS) and Spielberger State Anxiety Scale. Assessments were made at entry and following a 7-day single-blind placebo treatment phase, at the end of which only 51 wished to continue and had sufficient symptoms (HAS score >16 or reduction <25% on placebo) for entry to the next phase. Following a double- blind, random allocation they then received ICI 118,551 (50 mg), diazepam (2 mg) or placebo thrice daily for 4 weeks. Symptoms were assessed after 2 and 4 weeks in this active treatment phase (i.e. at weeks 3 and 5 of the study). Thirty-five patients completed the study. A statistically significant improvement in HAS score was seen for all patients but there were no significant differences between treatments. Treatments did not differ in their effects on blood pressure or heart rate. β(2)-Adrenoceptor antagonism does not seem to have important effects on anxiety symptoms in anxiety neurosis.  相似文献   
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