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81.
Heart complications are among the serious problems of patients with β-thalassemia intermedia. This study aimed to evaluate myocardial function in these patients. Clinical parameters and both standard Doppler and pulsed Doppler tissue imaging parameters were compared in 51 β-thalassemia intermedia patients (mean age, 17.05 ± 5.8 years) and 20 normal subjects (mean age, 17.81 ± 7.35 years, p = 0.98). In 11 patients (21.5%), pulmonary artery hypertension was detected. M-mode echocardiographic findings such as ejection fraction and fractional shortening did not show statistically significant changes (p > 0.005). Pulsed Doppler showed a significant difference in the early (E) to late diastolic (A) velocity ratio of the tricuspid and mitral valve between the patients and the control subjects (p < 0.05). In the pulsed tissue Doppler study, the peak systolic velocity of the septum (Ss), the peak atrial velocity of the septum (Aas), the peak systolic velocity of the tricuspid annulus (St), the peak early diastolic velocity of the tricuspid annulus (Eat), and the peak late diastolic velocity of the tricuspid annulus (Aat) were increased significantly (p < 0.05). The pulse tissue Doppler of the lateral mitral annulus did not change significantly (p > 0.005). The peak systolic velocity of the posterior wall and the peak late diastolic velocity of the anterior wall changed significantly (p < 0.05). This study showed that β-thalassemia intermedia patients with normal M-mode and two-dimensional echocardiography had statistically significant changes in pulsed Doppler and pulsed tissue Doppler imaging.  相似文献   
82.
This study investigates the effect of the nanostructure of squalene in the form of microemulsion on COVID-19 patients. In this blinded clinical trial, a comparison was made between the efficacy of squalene treatment and controls. A total of 30 COVID-19 patients admitted to the emergency department, and the infection ward was equally allocated to case (n = 15) and control (n = 15) groups according to their age and underlying diseases. The baseline characteristics of subjects, including age, gender, time of treatment onset, underlying condition, white blood cells count, and lymphocyte count were similar (p < 0.05). Baseline laboratory tests and computed tomography (CT) scans were performed for the study groups. The treatment group received 5 mg of intravenous squalene twice a day and standard treatment for 6 days, while controls received only standard treatment. After 6 days of treatment, clinical and CT scan changes were evaluated and compared in intervention and control groups. The need for oxygen therapy (p = 0.020), 2 days of no fever (p = 0.025), cough alleviation (p = 0.010), and lung high-resolution computed tomography improvement (p = 0.033) were significantly different between cases and controls within 7 days of admission. No adverse effects were observed in the treatment group. Our data suggest that squalene could be considered as a potential treatment for COVID-19, and further studies are required to confirm the results.  相似文献   
83.
Repair of large bone defects resulting from trauma, tumors, and osteitis is a current challenge to surgeons. Adipose-derived adult stem cells (ASCs) are multipotent cells that are able to differentiate into osteoblasts in the presence of certain factors. In this study, the role of greater omentum as a scaffold incorporation of ASCs was evaluated in long-bone defect healing in dog model. Sixteen 3-4-year-old, male adult mongrel dogs, weighing 25.2 ± 3.5 kg, were used in this study. In the control group (n = 4), the defect was left empty. In the omental group (n = 4), the defect was filled with harvested omentum. In the omental-ASCs group (n = 4), the defect was filled with omentum and 1 mL of ASCs was injected into the grafted omentum. In the omental-culture medium group (n = 4), 1 mL of culture medium was injected into the grafted omentum. Finally, the injured radial bones were fixed with plate and screw. Radiographs of each forelimb was taken postoperatively on the first day and at the second, fourth, sixth, and eighth weeks postinjury to evaluate bone formation, union, and remodeling of the defect. The operated radii were removed on the 56th postoperative day and were histopathologically evaluated. In this study, both omental-culture medium and omental-ASCs groups demonstrated superior osteogenic potential in healing the radial bone defect. Compared to those of the omental and control groups, more advanced bone healing criteria were present in the omental-culture medium and omental-ASCs groups at radiological and histopathological levels at 8 weeks postsurgery.  相似文献   
84.
Various molecular methods have been used for the rapid identification of mycobacterial species. In this survey, evaluation of antibiotic resistance and PCR-restriction fragment length polymorphism analysis (PRA) of the hsp65 gene was carried out for identification of non-tuberculosis mycobacteria (NTM) isolates from different clinical specimens. Forty-eight different mycobacterial isolates were selected and followed by the conventional and PRA of hsp65 for species identification. The antibiotic susceptibility test was carried out according to standard methods. A 439 bp PCR product of hsp65 in all selected isolates was amplified and digested with the BstEII and HaeIII restriction enzymes. The restriction fragment length polymorphism (RFLP) patterns were analyzed for species identification. Using PRA for 48 mycobacterial selected isolates, including 15 M. tuberculosis, one M. bovis and all 32 isolates of NTM, revealed 11 different species among the NTM isolates. The most frequent NTM isolates were M. kansasii, M. gordonae III, M. marinum, M. chelonae, M. scrofluaceum and M. gastri. In most cases, the PRA results were perfectly in accordance with the classical biochemical method. Combination of resistance to rifampin and isoniazid was present among M. kansasi, M. gordoniae III, M. scrofluaceum, M. chelonae, M. marinum, M. gastri, M. gordoniae II and M. trivale isolates. A high incidence of co-resistance to six, five, four and three anti-TB drugs was observed in 18.5%, 9.1%, 6.6% and 11.7% of all NTM isolates, respectively. Our results showed that PRA, in comparison with classical methods, is rapid and accurate enough for the identification of mycobacterial species from LJ medium. Additionally, we found that in Iran we have a highly diverse population of NTM isolates among patients suspected of having TB.  相似文献   
85.
A burn patient may require the most complicated treatment regimes encountered among trauma victims. Predicting the outcome of such treatment depends on several factors which have non-linear relationships. Traditional methods in prediction are "logistic regression" and "maximum likelihood". In this study, an artificial neural network (ANN) is used for computing survival among burn patients admitted to the "Motahary Burn Center", during a 1 year period (1996-1997). Fifteen different observations, such as total body surface area (TBSA), rescue time, admission period, surgery, inhalation injuries, etc. were obtained, retrospectively. A normal feed forward ANN was developed by Thinkspro software. It has 15 input-units, two hidden layers, and one output-unit. Survival was higher in males, those in whom early fluid resuscitation had been initiated and in patients in the middle of the age spectrum (P<0.0001). Strong correlations with these factors were noted.In the training phase, the ANNs accuracy reached 90%. In this study, the ANN has been applied for the first time to predict burn victim survival. This study can enable a different view point to help burn center physicians in the prediction of survival of their patients.  相似文献   
86.
Exposure to mercury can cause serious multiorgan damage affecting the central nervous system, kidneys, liver, lungs, spleen, bone marrow, and skin. At the end of the summer of 1999, the accidental leakage of 4 liters of mercury from a container into the waterway canals resulted in mass exposure to elemental mercury among the residents of a building block of a residential area of the city of Shiraz, in the south of Iran. One hundred and eleven individuals who experienced exposure to elemental mercury were investigated. Twenty-four-hour measurement of the urine mercury level-revealed a toxic level of more than 20 microg/L in 6 children and 3 adults (including a pregnant woman). Despite normal physical and laboratory (CBC, renal and liver function tests, and urinalysis) findings, dimercaprol was prescribed. One month later during the course of the follow-up the urine mercury level in 6 patients, including the pregnant woman from the same family, was found to be again at a toxic level. The pregnant mother from the same family aborted her fetus; however, due to the lack of equipment for measuring the serum mercury level, it was not possible to confirm the relation between the mercury toxicity and the abortion. This family had kept mercury in their kitchen against health workers' instructions. The attractive physical and chemical properties of mercury could explain the continuity of exposure and poisoning in these 6 cases. It is concluded that prophylactic therapy in the presence of toxic levels of mercury, despite the presence of an asymptomatic state in exposed residents, is effective in preventing the development of signs and symptoms, though instruction of high-risk cases is the best way to combat it.  相似文献   
87.
88.
Sentinel lymph node (SLN) biopsy is increasingly being used as an accurate and less morbid surrogate for axillary dissection. However, a standardized technique in the biopsy of SLNs is not used. Some authors propose subdermal injection to be as accurate as peritumoral intraparenchymal injection (IPI). Our objective is to determine whether the SLNs identified by subdermal injection truly represent SLNs and match those found with IPI. Specific end points of the study were 1) successful localization of the SLN by the IPI of isosulfan blue or the radiocolloid intradermal injection, 2) successful uptake of radiocolloid and isosulfan blue on individual SLN, and 3) determination of the frequency with which the radiocolloid injection detected the "gold standard" blue SLN. SLNs were found in 71 of 73 cases (success rate = 97%). Blue SLNs were identified in 64 patients (88%). SLNs in 61 patients (84%) were radioactive. A total of 112 SLNs were identified in 71 patients (1.6 nodes/patient). Seventy-six of 87 SLNs found with IPI were also radioactive (concordance of 87%). All SLNs harboring metastatic cancer (16 patients) were found by both techniques, being both blue and radioactive. Our results support the concept of shared lymphatic pathways in the breast with a high degree of communication between the subdermal lymphatics and the intraparenchymal lymphatics. The success in identification of the SLN is made simpler and improved by the addition of subdermal radiocolloid injection.  相似文献   
89.
90.
Spontaneous kidney allograft rupture   总被引:3,自引:0,他引:3  
Spontaneous renal allograft rupture is one of the most dangerous complications of kidney transplantation, which can result in graft loss. This condition needs immediate surgical intervention. Conservative management has dismal results. Its prevalence varies from 0.3% to 3%. Rupture occurs in first few weeks after transplantation. Predisposing factors for graft rupture are acute rejection, acute tubular necrosis, and renal vein thrombosis. There are growing reports about successful results of repairing these ruptured kidneys. In this study, we reviewed the medical records of 1682 patients who received kidney allografts from living donors from 1986 through 2003. There were six (0.35%) cases of renal allograft rupture. All were preceded by acute graft rejection. They were treated with antirejection medications. In first three cases, the kidney allografts were removed because the procedure of choice in this situation is graft nephrectomy; but in three next cases we repaired the ruptured grafts with good results in two of them. In conclusion, the procedure of choice for kidney allograft rupture is graft repair.  相似文献   
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