Context. Masses are a fundamental parameter, but they are not well known for most hot subdwarfs. In general, the mass of a hot subdwarf is derived with asteroseismology or dynamical methods, for which it is often difficult to obtain the necessary data from observations. Aims. We intend to find an approach to deriving the masses of hot subdwarfs from observational data in the literature. Methods. We presented full evolutionary calculations for hot subdwarfs in a wide mass range (0.33 M to 1.4 M ) for a Population I metallicity of Z = 0.02, and obtained a relation between M p and log, where M p , T eff , and g are the most probable mass, effective temperature, and gravity. This relation is used to study the masses of some observed hot subdwarfs. Results. We proposed a method of determining the masses of hot subdwarfs. Using this method, we studied the masses of hot subdwarfs from the ESO supernova Ia progenitor survey and Hamburg quasar survey. The study shows that most of subdwarf B stars have masses between 0.42 and 0.54 M , whilst most sdO stars are in the range 0.40 ∼ 0.55 M . Comparing our study to the theoretical mass distributions of Han et al. (2003, MNRAS, 341, 669), we found that sdO stars with mass less than ∼0.5 M may evolve from sdB stars, whilst most high-mass(>0.5 M ) sdO stars result from mergers directly.
Mass is a fundamental parameter, but the masses are not well known for most hot subdwarfs. We propose a method of determining the masses of hot subdwarfs. Using this method, we studied the masses of hot subdwarfs from the ESO supernova Ia progenitor survey and the Hamburg quasar survey. The study shows that most of the subdwarf B stars have masses between 0.42 and 0.54 M , whilst most sdO stars are in the range 0.40 ∼ 0.55 M . Comparing our study to the theoretical mass distributions of Han et al. (Mon. Not. R. Astron. Soc. 341:669, 2003), we found that sdO stars with mass less than ∼0.5 M may evolve from sdB stars, whilst most high-mass (>0.5 M ) sdO stars result from mergers directly.
Objective: Our study aimed to review the characters of primary diffuse large B-cell lymphoma (DLBCL) of ovary and provide recommendations of management for this rare disease. Methods: We presented 4 cases of primary ovarian DLBCL (PODLBCL) from Beijing Chaoyang Hospital between 2003 and 2021. Furthermore, we searched PubMed and Web of Science database for literature published between 1998 and 2021.A total of 16 articles included 24 cases with histopathologically confirmed PODLBCL and detailed evaluation and follow-up were reviewed. Results: The median age of patients with PODLBCL was 43y (5-73y). The main clinical symptoms were pelvic mass, abdominal pain, followed by irregular vaginal bleeding and urinary incontinence. 25% patients had bilateral ovarian tumors, and 61.1% of unilateral tumors were in the left ovary. Cancer antigen 125 (CA125) and serum lactate dehydrogenase (LDH) were usually elevated to varying degrees. Most cases were diagnosed by surgery and presented in early stage. Treatments included surgery, chemotherapy and monoclonal antibody therapy. There was no evidence of recurrence within a median follow-up time of 20 months (range 5-72 months) in 79.1% (19/21) of patients. Conclusions: PODLBCL had no significantly specific character to distinguish from ovarian epithelial malignant tumors. The prognosis of patients with PODLBCL was usually good. We proposed that chemotherapy combined with monoclonal antibody therapy may be the first-line treatment for PODLBCL, and surgical resection of the tumor may be avoided. The key problem is how to make an early preoperative diagnosis. Therefore, more case reports and institutional studies are needed to confirm these conclusions.
Objective: Our study aimed to observe the dynamic epidemiological characteristics of high-risk human papillomavirus (HR-HPV) infection among women in Beijing, China, between 2015 and 2020. Methods: A retrospective analysis was performed on all collected cervical specimens from women who underwent HR-HPV examination in the outpatient clinic, ward, and physical examination center of Beijing Chao yang Hospital, Capital Medical University, from April to December 2015, and from April to December 2020. Real-time polymerase chain reaction (PCR) was applied to detect 15 HR-HPV genotypes. Results: A total of 26003 patients were enrolled in the study. No statistical difference was detected in the HR-HPV infection rate between the two years (22.1% versus 23.1%, P>0.05). The top five genotypes were HPV52/58, 16, 56 and 51, in descending order in both years. Single HR-HPV infection was the most frequent infection type in both years. The proportion of single infection in 2015 and 2020 were 73.32% (2218/3025) and 76.22% (2167/2843), respectively. There was no significant difference in infection rates across age groups in 2015, but the infection rate curve of 2020 was “bimodal”, with two peaks in young women (≤24 years-old group) group and the 60-64 years-old (y) group, with the trough in the 45-49y group. Conclusions: There was no significant change in the overall HR-HPV infection rate of women in Beijing, and the genotype distribution of HR-HPV seldom changed except for the age-related infection rate during the last 5 years. These findings may provide baseline information for local administrations topromote targeted HPV screening and HPV vaccination.
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