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In this prospective study, we investigated the impact of SARS-CoV-2 infection on semen parameters in a cohort of men who had recently recovered from COVID-19. A total of 24 men who had recently recovered from mild COVID-19 were included in the study. Their semen parameters were normal before COVID-19 according to the World Health Organization 2010 reference values. Semen samples were collected from these participants in the recovery phases of COVID-19. To determine the effect of SARS-CoV-2 infection on semen parameters, the patients' pre-COVID-19 and post-COVID-19 semen analyses were compared. The mean age of the participants was 34.7 ± 6.4 years. The median interval between the positive nasopharyngeal swab test and obtaining semen samples was 111.5 (158) days. There was no significant difference in semen parameters before and after COVID-19 in terms of semen volume (p = .56), sperm concentration (p = .06), and progressive motility (p = .14). Total motility (p = .01) and total motile sperm count (p = .02) decreased significantly after SARS-CoV-2 infection compared to the pre-infection values. This study demonstrated that sperm motility and total motile sperm count were the semen parameters which showed a significant reduction in cases with a history of mild COVID-19.  相似文献   
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p53 is a key regulator of apoptosis. p53 upregulated modulator of apoptosis (PUMA) is a critical mediator of p53‐dependent and independent apoptosis. The objective of this study was to evaluate the relationship of p53 and PUMA to the prognosis of MDS. Bone marrow biopsies of MDS patients at the time of diagnosis (n = 76) and at the time of transformation (n = 19) were included in the study group. The expression of p53 and PUMA was evaluated using immunohistochemistry. When compared to the control group, both p53 (p < 0.001) and PUMA (p = 0.012) expression levels were significantly higher in MDS group. In MDS group, there was a moderate positive correlation between p53 and PUMA expressions. PUMA expression was not correlated with event free and overall survival. However, overall survival was significantly lower in cases with p53 expression in more than 50% of the cells. There was an increase in PUMA expression in cases that showed transformation as compared to the initial diagnostic bone marrows but was not statistically significant. The correlation that existed between p53 and PUMA was lost in transformed cases. Our results showed that PUMA and p53 expressions are increased in MDS marrows compared to normal marrows. PUMA expression increases further during transformation while the expression of p53 is not significantly altered which suggests that PUMA alterations might be a late event during the evolution of MDS.  相似文献   
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Background and purpose

Avascular necrosis (AVN) is a major cause of disability after treatment of developmental dysplasia of the hip (DDH), leading to femoral head deformity, acetabular dysplasia, and osteoarthritis in adult life. Type-II AVN is characterized by retarded growth in the lateral aspect of the physis or by premature lateral fusion, which produces a valgus deformity of the head on the neck of the femur. We investigated the effect of medial percutaneous hemi-epiphysiodesis as a novel technique in the treatment of late-diagnosed type-II AVN.

Patients and methods

9 patients (11 hips) with a diagnosis of type-II AVN who underwent medial percutaneous hemi-epiphysiodesis after the surgical treatment for DDH were included in the study. 10 patients (12 hips) with the same diagnosis but who did not undergo hemi-epiphysodesis were chosen as a control group. Preoperative and postoperative articulotrochanteric distances, head-shaft angles, CE (center-edge) angles, and physeal inclination angles were measured. The treatment group underwent medial hemi-epiphysodesis at a mean age of 8 years. The mean ages of the treatment group and the control group at final follow-up were 14 and 12 years respectively. The mean duration of follow-up was 5.7 years in the treatment group and 8.3 years in the control group.

Results

Preoperative articulotrochanteric distance, head-shaft angle, and functional outcome at the final follow-up assessment were similar in the 2 groups. However, preoperative and postoperative CE angles and physeal inclination angles differed significantly in the treatment group (p < 0.05). The final epiphyseal valgus angles were better in the treatment group than in the control group (p = 0.05). The treatment group improved after the operation.

Interpretation

Medial percutaneous epiphysiodesis performed through a mini-incision under fluoroscopic control is a worthwhile modality in terms of changing the valgus tilt of the femoral head.Avascular necrosis (AVN) of the proximal femoral epiphysis is an iatrogenic complication of treatment for developmental dysplasia of the hip (DDH) (Danielsson 2000, Dhar 2003, Domalzki and Synder 2004, Roposch et al.2013). A late abnormality that may be the manifestation of the lateral portion of the capital femoral growth plate in type-II AVN alters the morphology of hip joint (Kalamchi and MacEwen 1980). When a progressive valgus deformity occurs in a patient with type-II AVN, problems associated with hip dysplasia may follow (Siffert 1981, Campbell and Tarlos 1990, Kim et al. 2000, Wu et al. 2010, Herring 2014). Due to inadequate coverage, reduced contact area between acetabulum and femoral head leads to early secondary osteoarthritis (Aronson 1986, Inoue et al. 2000, Herring 2014).The treatment decision for type-II AVN is challenging. Procedures such as varus femoral osteotomy and redirectional acetabular osteotomy have been used with a view to preventing future degenerative disease. However, these procedures are technically difficult and may result in serious complications (Siebenrock et al. 2013). On the other hand, as the main pathology is the growth disturbance at the lateral aspect of the femoral head, some form of arrest of the medial portion of the growth plate may be more logical in the treatment of type-II AVN (Herring 2014). We analyzed the radiographic and clinical outcomes of 11 hips in 9 patients with late-diagnosed type-II AVN who underwent percutaneous hemi-epiphysiodesis of the femoral head.  相似文献   
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Among the potential risks of nasotracheal intubation are nasal bleeding, sinusitis, bacteremia, accidental turbinectomy, and some other structural damages. Retropharyngeal dissection is reported as a very rare complication of nasotracheal intubation, mostly encountered in elective surgery patients. A case with traumatic subcondylar fracture of the mandible is presented here, which is suspected to be the cause of the nasopharyngeal dissection that was observed during attempted nasotracheal intubation.  相似文献   
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