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101.
Seyed Hamidreza Monavari Mostafa Salehi vaziri Mohammadali Khalili Mahmoud Shamsi-Shahrabadi Hossein Keyvani Hamidreza Mollaei Mehdi Fazlalipour 《生物医学研究杂志》2013,27(1):56-61
In more than half of infertile men,the cause of their infertility is unknown.Several studies revealed the role of viral infections in male infertility.The aim of the present study was to determine the prevalence of herpes simplex virus-1 (HSV-1) and HSV-2 in semen from asymptomatic infertile male patients,and its association with altered semen parameters.A total of 70 semen samples were collected from infertile men who attended the Research and Clinical Center for Infertility in Yazd,Iran.Semen analysis and diagnostic real-time PCR using specific primers and probes for HSV-1 and HSV-2 DNA were performed.Comparison of semen parameters between virally infected and non-infected samples were performed with independent t-test and Mann-Whitney test.Semen analysis showed that infertile men fell into two groups,the male factor group and the unexplained group.HSV-1 and HSV-2 DNA was detected in 16 (22.9%) and 10 (14.3%) of 70 semen samples,respectively.All HSV-positive samples had abnormal semen parameters (the male factor group).Although HSV infection was not associated with sperm motility and morphological defects,it was correlated with lower sperm count in the seminal fluid.The findings suggest that asymptomatic seminal infection of HSV plays an important role in male infertility by adversely affecting sperm count. 相似文献
102.
Rania M. Nada Bram van Loon Thomas J.J. Maal Stefaan J. Bergé Yehya A. Mostafa Anne Marie Kuijpers-Jagtman Jan GJH Schols 《Clinical oral investigations》2013,17(9):2017-2024
Objectives
This study seeks to three-dimensionally assess soft tissue changes in the orofacial region following tooth-borne and bone-borne surgically assisted rapid maxillary expansion (SARME).Materials and methods
This prospective cohort study included 40 skeletally mature patients with transverse maxillary hypoplasia. A tooth-borne distractor (Hyrax) was used for expansion in 25 patients. In the remaining 15, a bone-borne distractor (transpalatal distractor, TPD) was used. Cone beam computed tomography (CBCT) scans were acquired before treatment (T0) and 22 months later (T1). 3D models were constructed from CBCT data and superimposed using voxel-based matching. Distance maps between the superimposed 3D models were computed to evaluate the degree of skeletal and soft tissue changes in the maxillary region.Results
Distance maps showed negative distances (mean ?1.25 (±1.5) mm) in the middle of the upper lip, indicating posterior repositioning of this area. The cheek region showed positive changes (mean 1.66 (±1.1) mm), reflecting the underlying increase in maxillary width. There was no significant difference between the two groups in all measured distances (p?>?0.05). Retro-positioning of the upper lip accompanied skeletal remodeling in the anterior alveolar region at a mean ratio of 88 %, while the cheek region followed 32 % of the alveolar expansion.Conclusion
Soft tissue changes following SARME include posterior repositioning of the upper lip and increased projection of the cheek area. These changes were comparable between bone-borne and tooth-borne appliances.Clinical relevance
This study provides clinicians with more information over the expected orofacial soft tissue changes following SARME 相似文献103.
104.
105.
Developments in the fields of lab-on-a-chip and microfluidic technology have benefited nanomaterial production processes due to fluid miniaturization. The ability to acquire, manage, create, and modify structures on a nanoscale is of great interest in scientific and technological fields. Recently, more attention has been paid to the production of core–shell nanomaterials because of their use in various fields, such as drug delivery. Heterostructured nanomaterials have more reliable performance than the individual core or shell materials. Nanoparticle synthesis is a complex process; therefore, various techniques exist for the production of different types of nanoparticles. Among these techniques, microfluidic methods are unique and reliable routes, which can be used to produce nanoparticles for drug delivery applications.Developments in the fields of lab-on-a-chip and microfluidic technology have benefited nanomaterial production processes due to fluid miniaturization. 相似文献
106.
Background
Neglected femoral neck fracture in young adults is an intriguing problem. This retrospective study tried to solve that challenge through open reduction, cannulated screw internal fixation, autogenous iliac bone and bone marrow grafting.Methods
Thirty-six cases were studied; they were classified according to Sandhu et al.'s classification. Twenty cases were type I and 16 cases were type II fractures; the mean age was 26.8 years; fracture neglect averaged 44.6 days. Twenty cases had posterior comminution and 16 cases had anterior comminution. All cases had open reduction, cannulated screw internal fixation, autogenous iliac bone and bone marrow grafting. The Harris hip score and Matta et al. grading system were applied for functional and radiological evaluation, respectively.Results
The average postoperative follow-up was 25.3 months; 94.4 % of the cases had solid union in a mean of 19.6 weeks. Functionally, the Harris hip score averaged 87.8 points. Nonunion, avascular necrosis and coxa vara complicated two, two and four cases, respectively. Fair and poor radiological results were related to coxa vara and avascular necrosis, respectively. Nonunion was significantly related to posterior comminution, type II neglected fracture, and a neglect of more than 45 days. Age groups more than 30 years old and postoperative neck-shaft angles <140° were significantly associated with late-onset radiological healing and nonunion.Conclusions
Cannulated screw osteosynthesis augmented by autogenous bone and bone marrow grafting is a simple, easy-to-perform surgical procedure with encouraging clinical outcomes for selected patients complaining of that difficult problem. 相似文献107.
To review long-term respiratory effects of mustard gas on Iranian veterans having undergone Iraq-Iran war. Electronic databases of Scopus, Medline, ISI, IranMedex, and Irandoc sites were searched. We accepted articles published in scientific journals as a quality criterion. The main pathogenic factors are free radical mediators. Prevalence of pulmonary involvement is approximately 42.5%. The most common complaints are cough and dyspnea. Major respiratory complications are chronic obstructive pulmonary disease, bronchiectasis, and asthma. Spirometry results can reveal restrictive and obstructive pulmonary disease. Plain chest X-ray does not help in about 50% of lung diseases. High-resolution CT of the lung is the best modality for diagnostic assessment of parenchymal lung and bronchi. There is no definite curative treatment for mustard lung. The effective treatment regimens consist of oxygen administration, use of vaporized moist air, respiratory physiotherapy, administration of mucolytic agents, bronchodilators, corticosteroids, and long-acting beta-2 agonists, antioxidants, surfactant, magnesium ions, therapeutic bronchoscopy, laser therapy, placement of respiratory stents, early tracheostomy in laryngospasm, and ultimately lung transplantation. High-resolution CT of the lung is the most accurate modality for the evaluation of the lung parenchyma and bronchi. The treatment efficacy of patients exposed to mustard gas depends on patient conditions (acute or chronic, upper or lower respiratory tract involvement). There are various treatment protocols, but unfortunately none of them is definitely curable. 相似文献
108.
This study aimed to assess the cavernous antioxidant effect of green tea (GT), epigallocatechin‐3‐gallate (EGCG) with/without sildenafil citrate intake in aged diabetic rats. One hundred and four aged male white albino rat were divided into controls that received ordinary chow, streptozotocin (STZ)‐induced aged diabetic rats, STZ‐induced diabetic rats on infused green tea, induced diabetic rats on epigallocatechin‐3‐gallate and STZ‐induced diabetic rats on sildenafil citrate added to EGCG. After 8 weeks, dissected cavernous tissues were assessed for gene expression of eNOS, cavernous malondialdehyde (MDA), glutathione peroxidase (GPx), cyclic guanosine monophosphate (cGMP), and serum testosterone (T). STZ‐induced diabetic rats on GT demonstrated significant increase in cavernous eNOS, cGMP, GPx and significant decrease in cavernous MDA compared with diabetic rats. Diabetic rats on EGCG demonstrated significant increase in cavernous eNOS, cGMP, GPx and significant decrease in cavernous MDA compared with diabetic rats or diabetic rats on GT. Diabetic rats on EGCG added to sildenafil showed significant increase in cavernous eNOS, cGMP and significant decrease in cavernous MDA compared with other groups. Serum T demonstrated nonsignificant difference between the investigated groups. It is concluded that GT and EGCG have significant cavernous antioxidant effects that are increased if sildenafil is added. 相似文献
109.
Mostafa Abdelkhalek Ayman M. Ali Mohamed Abdelwahab 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》2013,23(4):443-448
Aim
The purpose of this study is to evaluate the clinical and radiological outcomes of cemented bipolar arthroplasty as a primary treatment for unstable intertrochanteric fracture in the elderly patients.Methods
Twenty hips with unstable intertrochanteric fractures were followed for more than 2 years after cemented bipolar hemiarthroplasty. The mean age was 69 years, and the mean follow-up period was 30.5 months. We evaluated the results by Harris hip score, complications, and radiologic findings.Results
At the last follow-up, the mean Harris hip score was 83.3 points. Radiologically, there was no case of osteolysis. All stems were stable without significant changes in alignment or progressive subsidence.Conclusions
Bipolar hemiarthroplasty with calcar reconstruction is a good option for unstable intertrochanteric fractures in elderly patients with severe osteoporosis with strict indication selection. Longer-term studies with larger numbers of patients are required to address the issues of late complications. 相似文献110.
Ahmed Shafik Ismail Ahmed Olfat El Sibai Ali Shafik Randa Mostafa 《The journal of spinal cord medicine》2013,36(1):64-68
AbstractBackground/Objective: One of the causes of fecal incontinence is uninhibited rectal detrusor syndrome (URDS). Patients with this condition either perceived the first rectal sensation after the onset of involuntary rectal contraction or not at all. We investigated the hypothesis that the abnormal rectal contractility in URDS may be caused by deranged rectal electric activity.Methods: Twenty-five patients with URD (14 women and 11 men; age, 44.7 ± 10.3 years) and 10 healthy volunteers (6 women and 4 men; age, 42.8 ± 8.7 years) were studied. URDS was diagnosed by rectometry and provocative test. A transcutaneous EMG was performed with one electrode placed lateral to each sacroiliac joint and the third one midway between the greater trochanter and the ischial tuberosity. Two 20- minute recording sessions were performed for each subject.Results: Slow waves (SWs) with regular rhythm and similar parameters (frequency, amplitude, conduction velocity) from the 3 electrodes were recorded from the healthy volunteers. They showed a significant increase in the parameters on saline filling of the rectum. The SWs of patients with URDS exhibited a “dysrhythmic” pattern with irregular parameters, which were different in the 3 electrodes and inconsistent during recording. They showed areas of tachyrhythmia, bradyrhythmia, and arrhythmia. On provoking rectal overactivity, the SWs showed an increased dysrhythmic activity.Conclusions: The patients with URD exhibited a “dysrhythmic” electric pattern with areas of variable electric activity. The tachyrhythmic areas seem to initiate the urgency and fecal incontinence of URDS. It is suggested that a disordered rectosigmoid pacemaker causes the dysrhythmic waves. 相似文献