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Purpose:The proportion of axial length (AL) occupied by vitreous chamber depth (VCD), or VCD:AL, consistently correlates to ocular biometry in the general population. Relation of VCD:AL to ocular biometry in high myopia is not known. The purpose of this study is to evaluate the relation of VCD and VCD:AL to ocular biometry of highly myopic eyes.Methods:This was a cross-sectional retrospective study of records of 214 myopic eyes (<−1 D SE, aged 20–40 years) attending the refractive surgery services. High axial myopia was defined as AL >26.5 mm. Eyes with posterior staphyloma and myopic maculopathy were excluded. Records were assessed for measurements of AL, central corneal thickness (CCT), anterior chamber depth (ACD), lens thickness (LT), white to white diameter (WTW), and vitreous chamber depth (VCD). Groups were formed based on increasing AL, while the sum of CCT, ACD, and LT was recorded as anterior segment depth (AS). The main outcome measure was the correlation of VCD and VCD:AL to ocular biometry. A comparison was also performed based on of degree of axial myopia.Results:Mean age of the patients was 27.0 ± 5.2 years. VCD showed a very strong correlation with AL (R = 0.98, P < 0.001) but did not correlate to any anterior parameter. VCD:AL showed moderate negative relation with AS (R = −0.43, P < 0.001) and ACD (R = −0.3, P < 0.001), while it had a weakly negative relation with LT (R = −0.18, P = 0.006). VCD:AL showed strong negative relation (R > ~0.7) with AS in all individual groups of AL. Among anterior parameters, WTW showed the most consistent relation with ocular biometry.Conclusion:VCD:AL is a better correlate of ocular biometry in high myopia as compared to VCD. However, the correlation is weaker than that noted by previous studies done on the general population. Longitudinal studies of VCD:AL in the younger age group is recommended.  相似文献   
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Progesterone has been implicated in the process of spermatogenesis. This study aimed to investigate the association of progesterone receptor (PR) expression with spermatogenesis in the testis of infertile men. PR mRNA and protein were assessed by in-situ hybridization and immunohistochemistry in testicular biopsies obtained from 18 infertile men. The extent of spermatogenesis was assessed by Johnsen scoring. None of the patients included in the study had Yq microdeletions. PR expression was almost undetectable in all the testicular sections displaying Sertoli cell only (SCO) or arrest at spermatogonia. Weak cytoplasmic expression was observed in biopsies showing arrest at different stages of meiosis. In biopsies displaying spermatogenesis up to the round spermatid stages, PR expression was observed in both nucleus and cytoplasm of different cell types at intensity lower than that detected in normal biopsies. Normal PR expression was observed in biopsies demonstrating hypospermatogenesis. In biopsies showing mixed phenotypes, the tubules with SCO or spermatogonia arrest showed absence of PR expression; normal PR expression was observed in adjacent tubules showing complete spermatogenesis. Semi-quantitative assessment of PR expression and Johnsen scores in the testicular biopsies of infertile men demonstrating different phenotypes indicated a direct relationship between PR expression and extent of spermatogenesis.  相似文献   
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ObjectiveThe objective of this study is to assess the utility of a nucleic acid amplification test‐based approach to shorten isolation of healthcare workers (HCWs) with COVID‐19 in the setting of the highly transmissible omicron variant.MethodsBetween December 24, 2021, and January 5, 2022, HCWs who tested positive for SARS‐CoV‐2 were retested with PCR at least 5 days since onset of symptoms.ResultsForty‐six sequential fully COVID‐19 vaccinated HCWs who had tested positive for SARS‐CoV‐2 underwent follow‐up testing. All the samples were confirmed as omicron variants and only four (8.7%) were negative in the follow‐up test performed at a median of 6 (range 5–12) since onset of symptoms.ConclusionsImplementation of a test‐based strategy is logistically challenging, increases costs, and did not lead to shorter isolation in our institution.  相似文献   
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A case of monkeypox was diagnosed in a returning traveler from Nigeria to Maryland, USA. Prompt infection control measures led to no secondary cases in 40 exposed healthcare workers. Given the global health implications, public health systems should be aware of effective strategies to mitigate the potential spread of monkeypox.  相似文献   
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Pre-cervical inflammation is rarely seen in a newborn. Those swellings that are seen are usually congenital, such as vascular malformations, teratoma, dermoid cyst, thyroglossal cyst, cystic hygroma (abnormal lymphatic tissue), and very rarely, inflammation secondary to infection. Being able to differentiate between each condition is important because the course, treatment and prognosis for each condition are different. This case of a neck abscess in a newborn is reported due to its resemblance to cystic hygroma and highlights the similarities between the two conditions.  相似文献   
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