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51.
Background: One of the most challenging problems in clinical surgery is management of an extensive duodenal injury. In its management, there are limitations in using jejunal serosal patch and other conventional methods in specific conditions. This study was performed to compare treatment of large duodenal defects by a gallbladder serosal patch and the gallbladder mucosal patch in a dog as an animal model. Methods: A duodenal defect (2 cm, about 50% of the total circumference) was created in the second portion of the duodenum in eight dogs. The animals were divided into two equal groups, with group 1 undergoing serosal patch repair and group 2 undergoing mucosal patch repair. The macroscopic and microscopic healing features of the gallbladder serosal and mucosal patch were compared. Results: None of the dogs died due to surgical complications. The whole grafted area was covered by neomucosa at the end of the third week in all animals with the gallbladder serosal patch (group 1). In this group, the scar was small; no significant narrowing of lumen was noted and serosal healing was uniformly complete. In histological examination, a complete coverage of the gallbladder serosal patch by neomucosa consisting of columnar epithelium with short villous formations was observed. In mucosal patch models (group 2), complete epitheliazation, mild fibrosis, and incomplete repair were visible. In histological examination, severe inflammation was noticed too. Conclusion: In patients with multiple trauma affecting upper gastrointestinal tracts, use of the gallbladder serosal patch method is easy and reliable. So it may be considered in the surgical management of large duodenal defects, which cannot be repaired by available conventional methods.  相似文献   
52.
The alpha-synuclein–caveolin 1 axis is suggested to be of role in the pathogenesis of Parkinson’s disease in cell line models. The objective of this study was to analyze the homozygous haplotype compartment of the human caveolin 1 gene upstream purine complex in patients afflicted with Parkinson’s disease. This complex was screened in patients with Parkinson’s disease (n?=?141) and compared with a group of controls (n?=?760) using polymerase chain reaction and sequencing. The expression activity of the homozygous haplotypes was then examined using luciferase Dual-Glo system in human neuronal cell line, LAN-5. Six haplotypes were found to be homozygous in the patients, and not in the control pool (Fisher exact p?<?1?×?10?6). Three of those haplotypes were specific to Parkinson’s disease (Fisher exact p?<?0.002), and the remaining three overlapped with homozygous haplotypes in Alzheimer’s disease and multiple sclerosis (Fisher exact p?<?0.002). The disease haplotypes contained motif lengths that were nonexistent in the control homozygous haplotype pool and significantly increased gene expression (p?<?9?×?10—6). We conclude that skew in the caveolin 1 purine complex homozygous haplotype compartment and an additive effect of those haplotypes may be linked with Parkinson’s disease.  相似文献   
53.
Although poly (ionic liquids) (PILs) have attracted great research interest owing to their various applications, the performance of nanoporous PILs has been rarely developed in the catalysis field. To this end, a micro–mesoporous PIL with acid–base bifunctional active sites was designed and fabricated by two different polymerization protocols including hydrothermal and classical precipitation polymerization in this paper. Based on our observations, hydrothermal conditions (high temperature and pressure) enabled the proposed sonocatalyst to possess a great porous structure with a high specific surface area (SBET: 315 m2 g−1) and thermal stability (around 450 °C for 45% weight loss) through strengthening cross-linking. In a comparative study, the preferred nanoporous PIL was selected and utilized as the sonocatalyst in a multicomponent reaction of isatins, primary amines, and thioglycolic acid. In the following, a variety of new and known pharmaceutical spiro-4-thiazolidinone derivatives were synthesized at room temperature and obtained excellent yields (>90%) within short reaction times (4–12 min) owing to the substantial synergistic effect between ultrasound irradiation and magnetically separable catalyst.

Sustainable synthesize of a new mesoporous poly (ionic liquid) as acid–base bifunctional catalyst for environmental being preparation of monospiro derivatives has been developed.  相似文献   
54.
Brucellosis is associated with a high recurrence rate and requires more than one course of standard treatment; therefore, more research is required to find more effective treatments that lead to prompt recovery, and reduce the relapse of disease. This single-blind, randomized study was designed to evaluate the effect of the standard treatment for brucellosis in combination with hydroxychloroquine.A total of 177 patients with acute brucellosis were randomly assigned to one of two treatment groups: doxycycline-streptomycin (DS) and doxycycline-streptomycin-hydroxychloroquine (DSH). Clinical symptoms and signs, serological tests, and side effects of therapy were compared between the two groups during the treatment course and at three and six months after the end of drug therapy. Of the 177 patients, with a mean age of 40.5?±?16.9 years, 66.1% were males. The mean duration of clinical signs prior to admission was 43.4?±?41.1 days. Appropriate clinical responses, relapse, treatment failure, and adverse drug reactions were seen in 98.9%, 1.2%, 0.0%, and 12.6% of patients, respectively, in the DSH group vs. 86.7%, 11.6%, 2.3%, and 19.8% of patients, respectively, in the DS group. There were significant differences in clinical response and relapse rates between the two groups. The addition of hydroxychloroquine to a doxycycline-streptomycin regimen appears to increase the efficacy of treatment, accelerate improvement of clinical symptoms, and significantly reduce the rate of relapse of brucellosis.  相似文献   
55.
Origanum species are mostly distributed around the Mediterranean, Euro‐Siberian, and Iran‐Siberian regions. Since time immemorial, the genus has popularly been used in Southern Europe, as well as on the American continent as a spice now known all over the world under the name “oregano” or “pizza‐spice.” Origanum plants are also employed to prepare bitter tinctures, wines, vermouths, beer, and kvass. The major components of Origanum essential oil are various terpenes, phenols, phenolic acids, and flavonoids with predominant occurrence of carvacrol and thymol (with reasonable amounts of p‐cymen and ‐terpinene) or of terpinene‐4‐ol, linalool, and sabinene hydrate. Many species of Origanum genus are used to treat kidney, digestive, nervous, and respiratory disorders, spasms, sore throat, diabetes, lean menstruation, hypertension, cold, insomnia, toothache, headache, epilepsy, urinary tract infections, etc. Origanum essential oil showed potent bioactivities owing to its major constituents' carvacrol, thymol, and monoterpenes. Several preclinical studies evidenced its pharmacological potential as antiproliferative or anticancer, antidiabetic, antihyperlipidemic, anti‐obesity, renoprotective, antiinflammatory, vasoprotective, cardioprotective, antinociceptive, insecticidal, and hepatoprotective properties. Its nanotechnological applications as a promising pharmaceutical in order to enhance the solubility, physicochemical stability, and the accumulation rate of its essential oils have been investigated. However, Origanum has been reported causing angioedema, perioral dermatitis, allergic reaction, inhibition of platelet aggregation, hypoglycemia, and abortion. Conclusive evidences are still required for its clinical applications against human medical conditions. Toxicity analyses and risk assessment will aid to its safe and efficacious application. In addition, elaborate structure–activity studies are needed to explore the potential use of Origanum‐derived phytochemicals as promising drug candidates.  相似文献   
56.
In this article, we consider the optimal topology design and distributed formation control problem of multiagent systems (MAS) with complex-weighted directed topology. First, a framework is proposed to associate optimal topology of MAS to a constrained optimization problem with a complex Laplacian matrix, which is independent of the agent dynamics. The main contribution of the proposed approach compared with existing results is that the proposed approach does not require the calculation of the stabilizing matrix such that the closed-loop system is asymptotically stable, and a unique set of complex weights that satisfy associated cooperative conditions can be chosen. Then, a distributed formation control protocol is proposed to enable all agents to achieve the control goal. Finally, some numerical example results are provided to demonstrate the effectiveness of the proposed scheme.  相似文献   
57.
This article proposes a Fuzzy Second Order Integral Terminal Sliding Mode (FSOITSM) control approach for DFIG-based wind turbines subject to grid faults and parameter variations. Since traditional terminal sliding mode control (SMC) suffers from singularity, a novel integral terminal sliding manifold is proposed to eliminate chattering and improve the wind turbine's performance in the presence of faults and disturbances. A fuzzy system is proposed to auto-tune the controllers' gains and ensures the invariance of the sliding surfaces even under heavy uncertainties, thus further improving the reliability and performance of the proposed controller. The performance of the proposed approach was assessed under various operating conditions. A comparison analysis with a standard SMC approach as well as the state of the art in voltage sag mitigation was also carried over. Reliability, robustness, and power availability under faulty grid conditions are among the main features of the proposed approach. In addition, the proposed approach exhibited chattering free dynamics and enabled the finite time convergence of the sliding manifold and overcame the singularity problem associated with standard TSMC.  相似文献   
58.
59.

Background and aims

Currently, there is no widely accepted evidence-based pharmacotherapy regime for the treatment of psychostimulant dependence. Yet, different pharmacological approaches have been tried in the treatment of MA addiction. The present study was conducted to compare efficiency of methylphenidate which is relatively easily accessible in our country, with resperidone for this purpose.

Methods

Eighty-six patients with MA dependence according to criteria defined by DSM IV-TR were divided into two groups. Patients in group R were given oral resperidone 1 mg daily for 1 week; then 2 mg daily in a divided dose for 3 weeks. Patients in group M were given oral methylphenidate 10 mg daily for 2 weeks, 7.5 mg daily for 1 week, then 5 mg daily for 1 week. They were evaluated for drug craving, psychological, neurologic and somatic symptoms at the start and end of the study.

Findings

Both drugs were useful for lowering drug craving in patients; however resperidone was more effective (6.31 ± 8.31 vs.19.6 ± 12.45 cravings per week, respectively). The effects of resperidone were more notable in lowering frequency and intensity of psychiatric, neurologic, cardiac and somatic symptoms of the patients after discontinuation of MA abuse; however methylphenidate was effective too; though with a lower potency.

Conclusion

The present study confirmed that both methylphenidate and resperidone can successfully be used for treatment of MA dependence, in order to reduce drug craving and psychological, neurologic, and somatic problems in patients. However, the efficacy of methylphenidate was estimated to be less than that of resperidone for this purpose.  相似文献   
60.
Revision total knee arthroplasty (TKA) in the setting of bone deficiency requires varied levels of constraint to restore knee stability. However, the outcomes between different levels remain controversial. Clinical outcomes for 183 AORI Type I knees, 168 Type II knees and 124 Type III knees utilizing posterior stabilized (PS), unlinked constrained (UC) or hinged prostheses were evaluated with standardized clinical assessment tools and radiographic results over an average of 7.4 years. PS yielded superior knee scores in AORI Type I patients (P < 0.05), UC in Type II and III aseptic patients (P < 0.05), and a hinge was preferred in septic Type II or III knees (P < 0.05). Revision TKA conducted with increased constraint appears effective in the setting of increased bone deficiency.  相似文献   
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