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Varicocele occurs in approximately 15% to 20% of the general male population and it is the most common cause of poor semen production and decreased semen quality. It has been demonstrated that patients with varicocele have a significantly higher DNA fragmentation index (DFI) and spermatozoa with nuclear anomalies than healthy fertile men. Therefore, the aim of this study was to evaluate sperm chromatin integrity in these patients. Sixty men referring to the andrology laboratory were categorised into three different groups: 20 infertile men with varicocele, 20 infertile men with abnormal semen parameters and 20 fertile men who had normal spermatogram were considered as control group. Semen analysis was performed according to WHO criteria. To evaluate sperm chromatin quality and DNA integrity, after fixation of sperm smears, aniline blue, toluidine blue, chromomycin A3 and acridine orange staining were applied in three groups. The slides were analysed by light and fluorescent microscopy and to determine the percentage of mature or immature spermatozoa, 200 spermatozoa were counted in each slide. The results showed that the rates of aniline blue-reacted spermatozoa were significantly higher in infertile and varicocele patients than in the normal group ( P  < 0.001). In addition, with regard to chromomycin A3, acridine orange and toluidine blue staining, there was a significant difference between the three groups ( P  < 0.001). The results showed that the varicocele samples contain a higher proportion of spermatozoa with abnormal DNA and immature chromatin than those from fertile men as well as infertile men without varicocele. Therefore, varicocele results in the production of spermatozoa with less condensed chromatin and this is one of the possible causes of infertility due to varicocele.  相似文献   
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Tumor Biology - The three amino acid loop extension (TALE) class myeloid ecotropic viral integration site 1 (MEIS1) homeobox gene is known to play a crucial role in normal and tumor development. In...  相似文献   
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Methicilin resistance Staphylococcus aureus (MRSA) infections are the major challenges in hospitals, especially in the burn units. The use of molecular typing methods is essential for tracking the spread of S. aureus infection and epidemiological investigations. The aim of this study was to find the profile of the spa types and also the prevalence of each SCCmec type of S. aureus strains in a central burn hospital in southwest of Iran. A total of 81 non‐duplicate S. aureus were isolated from burn patients between April 2011 and February 2012. The susceptibility of the isolates against 13 different antibiotics was tested by disk agar diffusion (DAD) method. MRSA strains were identified by amplification of mecA gene. Multiplex‐polymerase chain reaction (PCR) technique was used to determine the SCCmec types of MRSA strains and all the S. aureus isolates were typed by spa typing method. Detection of mecA gene showed that 70 (86.4%) of the isolates were MRSA. The highest rate of resistance was observed for penicillin (97.5%) and erythromycin (77.8%). None of the isolates were resistant to vancomycin. Sixty‐seven of the 70 MRSA isolates harbored only SCCmec type III and three untypeable isolates. Five different spa types were detected. The most common spa types were t037 (42.5%) and t631 (34.5%) and were only found in MRSA isolates. Only SCCmec type III was found in burn patients which emphasizes the HA‐MRSA origin of these strains. Only five different spa types identified in this study are in accordance with one SCCmec type which indicates that a limited number of bacterial colons are circulated in the burn unit in this hospital.  相似文献   
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The aim of the study was to investigate the impact of supplementation with flaxseed on plasma lipoprotein(a) [Lp(a)] levels through a systematic review and meta‐analysis of eligible randomized placebo‐controlled trials. PubMed, Scopus, Cochrane Library, and ISI Web of Science were searched for randomized controlled trials (RCTs) which have been published up to November 2019. RCTs that investigated the effect of flaxseed supplementation on plasma Lp(a) levels in adults were included for final analysis. The random effects model was used for calculating the overall effects. Meta‐analysis of 7 selected RCTs with 629 individuals showed significant lowering effect of flaxseed supplementation on Lp(a) (MD ?2.06 mg/dl; 95% CI: ?3.846, ?0.274, p = .024), without considerable heterogeneity between studies (p = .986, I2 = 0%). Subgroup analysis also revealed that longer duration only showed significant lowering effect of flaxseed supplementation on Lp(a). This meta‐analysis has shown that flaxseed supplementation might significantly decrease plasma Lp(a) levels. Future well‐designed and long‐term clinical trials are required to confirm these results.  相似文献   
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PurposeTo prepare for future possible communicable disease epidemics/pandemics, health care providers should know how the COVID-19 pandemic influenced injured patients. This study aimed to compare epidemiologic features, outcomes, and diagnostic and therapeutic procedures of trauma patients admitted to a university-affiliated hospital before and during the pandemic.MethodsThis retrospective study was performed on data from the National Trauma Registry of Iran. All injured patients admitted to the hospital from July 25, 2016 to March 10, 2021 were included in the study. The patients were excluded if they had hospital length of stay less than 24 h. The injury outcomes, trauma mechanisms, and therapeutic and diagnostic procedures of the 2 periods: before (from July 25, 2016 to February 18, 2020) and during (from February 19, 2020 to March 10, 2021) COVID-19 pandemic were compared. All analyses were performed using STATA version 14.0 software (Stata Corporation, College Station, TX).ResultsTotally, 5014 patients were included in the registry. Of them, 773 (15.4%) were registered after the beginning of the COVID-19 pandemic on February 19, 2020, while 4241 were registered before that. Gender, education level, and cause of injury were significantly different among the patients before and after the beginning of the pandemic (p < 0.001). In the ≤ 15 years and ≥ 65 years age groups, injuries decreased significantly during the COVID-19 pandemic (p < 0.001). The frequency of intensive care unit (ICU) admission decreased from 694 (16.4%) to 88 (11.4%) (p < 0.001). The mean length of stay at the hospital (days) and at the ICU (days) declined as follow: 8.3 (SD = 17.2) vs. 5.5 (SD = 6.1), p < 0.001 and 7.5 (SD = 11.5) vs. 4.5 (SD = 6.3), p < 0.022. The frequency of diagnostic and therapeutic procedures before and during the pandemic was as follows, respectively: ultrasonography 905 (21.3%) vs. 417 (53.9%) (p < 0.001), echocardiography 313 (7.4%) vs. 107 (13.8%) (p < 0.001), angiography 1597 (37.7%) vs. 534 (69.1%) (p < 0.001), MRI 166 (3.9%) vs. 51 (6.6%) (p < 0.001), surgery 3407 (80.3%) vs. 654 (84.6%) (p < 0.001), and internal/external fixation 1215 (28.6%) vs. 336 (43.5%) (p < 0.001).ConclusionThe pandemic affected the epidemiology of traumatic patients in terms of gender, age, educational level, and trauma mechanism. It changed the outcomes of injured patients: ICU admission, length of stay at the hospital and ICU decreased. The patients received more diagnostic and therapeutic procedures during the pandemic. To be more precise, more research is needed on the details.  相似文献   
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Simultaneous visualization of the teeth and periodontium is of significant clinical interest for image-based monitoring of periodontal health. We recently reported the application of a dual-modality photoacoustic-ultrasound (PA-US) imaging system for resolving periodontal anatomy and periodontal pocket depths in humans. This work utilized a linear array transducer attached to a stepper motor to generate 3D images via maximum intensity projection. This prior work also used a medical head immobilizer to reduce artifacts during volume rendering caused by motion from the subject (e.g., breathing, minor head movements). However, this solution does not completely eliminate motion artifacts while also complicating the imaging procedure and causing patient discomfort. To address this issue, we report the implementation of an image registration technique to correctly align B-mode PA-US images and generate artifact-free 2D cross-sections. Application of the deshaking technique to PA phantoms revealed 80% similarity to the ground truth when shaking was intentionally applied during stepper motor scans. Images from handheld sweeps could also be deshaken using an LED PA-US scanner. In ex vivo porcine mandibles, pigmentation of the enamel was well-estimated within 0.1 mm error. The pocket depth measured in a healthy human subject was also in good agreement with our prior study. This report demonstrates that a modality-independent registration technique can be applied to clinically relevant PA-US scans of the periodontium to reduce operator burden of skill and subject discomfort while showing potential for handheld clinical periodontal imaging.  相似文献   
100.
A fluororeceptor assay (FRA) has been developed for the determination of antibodies against acetylcholine receptor (AChR), employing an antifluorescein serum and fluorescein-labeled AChR. Antiserum raised against rat muscle AChR in rabbit and the labeled AChR are incubated with antifluorescein serum at room temperature. At high levels of anti-AChR, binding of the labeled AChR prevented subsequent binding of the fluorescein groups by antifluorescein, resulting in little change in the signals of the label. Conversely, at low levels of anti-AChR, the free fraction of the labeled AChR is available to be bound by antifluorescein, which markedly reduced fluorescence intensity of the label. Thus, the fluorescence intensity of the assay mixture directly reflects the amount of anti-AChR antibodies in the serum. It is concluded that the availability of fluorescein-labeled AChR and the antibody directed against it permit measurement of anti-AChR antibodies in human myasthenia. The quality of the assay and its preliminary clinical application have been evaluated.  相似文献   
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