Access block,known as exit block or boarding,is defined as a situation in which patients who are admitted or planned for admission remain in the emergency department(ED)as they are unable to be transferred to an inpat...Access block,known as exit block or boarding,is defined as a situation in which patients who are admitted or planned for admission remain in the emergency department(ED)as they are unable to be transferred to an inpatient unit within a reasonable time frame(no longer than 8 hours).[1,2]Access block often occurs due to insufficient hospital capacity and is a major issue in emergency medicine.[3]展开更多
Recurrence is common among patients undergoing hepatic resection for hepatocellular carcinoma(HCC),which greatly limits long-term survival.We aimed to identify predictors and long-term prognosis of early and late recu...Recurrence is common among patients undergoing hepatic resection for hepatocellular carcinoma(HCC),which greatly limits long-term survival.We aimed to identify predictors and long-term prognosis of early and late recurrence after HCC resection.Methods:Multicenter data of patients who underwent HCC resection between 2002 and 2016 were analyzed.Recurrence was divided into early(≤2 years)and late recurrence(>2 years after surgery).Predictors of early and late recurrence,and prognostic factors of post-recurrence survival(PRS)were identified by univariate and multivariate analyses.Results:Among 1,426 patients,554(38.8%)and 348(24.4%)developed early and late recurrence,respectively.Independent predictors associated with early recurrence included preoperative alpha-fetoprotein level>400μg/L,resection margin<1 cm,and tumor size>5.0 cm,multiplicity,macrovascular and microvascular invasion,and satellites of the initial tumor at the first diagnosis of HCC;independent predictors associated with late recurrence included male,cirrhosis,and tumor size>5.0 cm,multiplicity,macrovascular and microvascular invasion,and satellites of the initial tumor.Patients with early recurrence had a lower likelihood of undergoing potentially curative treatments for recurrence(37.2%vs.48.0%,P<0.001)and a worse median PRS(13.5 vs.36.6 months,P<0.001)vs.patients who had late recurrence.Multivariate analysis revealed that early recurrence and irregular postoperative surveillance were independently associated with worse PRS[hazard ratio(HR)=1.250,95%CI:1.016-1.538,P=0.035;and HR=1.983,95%CI:1.677-2.345,P<0.001].Conclusions:Predictors associated with early and late recurrence after curative resection for patients with HCC were generally same,although several did differ.Patients with late recurrence had better long-term survival than patients with early recurrence.展开更多
Background:A solitary hepatocellular carcinoma(HCC)without macrovascular invasion and distant metastasis,regardless of tumor size,is currently classified as early-stage disease by the latest Barcelona Clinic Liver Can...Background:A solitary hepatocellular carcinoma(HCC)without macrovascular invasion and distant metastasis,regardless of tumor size,is currently classified as early-stage disease by the latest Barcelona Clinic Liver Cancer(BCLC)staging system.While the preferred treatment is surgical resection,the association of tumor morphology with long-term survival outcomes after liver resection for a solitary huge HCC of≥10 cm has not been defined.Methods:Patients who underwent curative liver resection for a solitary huge HCC were identified from a multicenter database.Preoperative imaging findings were used to define spherical-or ellipsoidal-shaped lesions with smooth edges as balloon-shaped HCCs(BS-HCCs);out-of-shape lesions or lesions of any shape with matt edges were defined as non-balloon-shaped HCCs(NBS-HCCs).The two groups of patients with BS-HCCs and NBS-HCCs were matched in a 1:1 ratio using propensity score matching(PSM).Clinicopathologic characteristics,long-term overall survival(OS)and recurrence-free survival(RFS)were assessed.Results:Among patients with a solitary huge HCC,74 pairs of patients with BS-HCC and NBS-HCC were matched.Tumor pathological features including proportions of microvascular invasion,satellite nodules,and incomplete tumor encapsulation in the BS-HCC group were lower than the NBS-HCC group.At a median follow-up of 50.7 months,median OS and RFS of all patients with a solitary huge HCC after PSM were 27.8 and 10.1 months,respectively.The BS-HCC group had better median OS and RFS than the NBS-HCC group(31.9 vs.21.0 months,P=0.01;and 19.7 vs.6.4 months,P=0.015).Multivariate analyses identified BS-HCC as independently associated with better OS(HR=0.592,P=0.009)and RFS(HR=0.633,P=0.013).Conclusions:For a solitary huge HCC,preoperative imaging on tumor morphology was associated with prognosis following resection.In particular,patients with BS-HCCs had better long-term survival following liver resection versus patients with large NBS-HCCs.展开更多
The near-Earth(within~100 pc)supernova explosions in the past several million years can cause the global deposition of radioactive elements(e.g.,60Fe)on Earth.The remnants of such supernovae are too old to be easily i...The near-Earth(within~100 pc)supernova explosions in the past several million years can cause the global deposition of radioactive elements(e.g.,60Fe)on Earth.The remnants of such supernovae are too old to be easily identified.It is therefore of great interest to search for million-year-old near-Earth neutron stars or black holes,the products of supernovae.However,neutron stars and black holes are challenging to find even in our Solar neighbourhood if they are not radio pulsars or X-ray/γ-ray emitters.Here we report the discovery of one of the nearest(127.7±0.3 pc)neutron star candidates in a detached single-lined spectroscopic binary LAMOST J235456.73+335625.9(hereafter J2354).Utilizing the time-resolved ground-based spectroscopy and space photometry,we find that J2354 hosts an unseen compact object with M_(inv)being 1.4-1.6 M_(⊙).The follow-up Swift ultraviolet(UV)and X-ray observations suggest that the UV and X-ray emission is produced by the visible star rather than the compact object.Hence,J2354 probably harbours a neutron star rather than a hot ultramassive white dwarf.Two-hour exceptionally sensitive radio follow-up observations with Five-hundred-meter Aperture Spherical radio Telescope fail to reveal any pulsating radio signals at the 6σflux upper limit of 12.5μJy.Therefore,the neutron star candidate in J2354 can only be revealed via our time-resolved observations.Interestingly,the distance between J2354 and our Earth can be as close as~50 pc around 2.5 million years(Myrs)ago,as revealed by the Gaia kinematics.Our discovery demonstrates a promising way to unveil the hidden near-Earth neutron stars in binaries by exploring the optical time domain,thereby facilitating understanding of the metal-enrichment history in our Solar neighbourhood.展开更多
The paper“Compact object candidates with K/M-dwarf com-panions from LAMOST low-resolution survey”[1]was pub-lished in SCIENCE CHINA Physics,Mechanics&Astronomy(65,229711(2022).doi:10.1007/s11433-021-1809-8).Due ...The paper“Compact object candidates with K/M-dwarf com-panions from LAMOST low-resolution survey”[1]was pub-lished in SCIENCE CHINA Physics,Mechanics&Astronomy(65,229711(2022).doi:10.1007/s11433-021-1809-8).Due to an oversight on our part,some errors were made in the originally published paper.We apologize for these errors and offer the corresponding explanations and corrections for the readers.展开更多
Searching for compact objects(black holes,neutron stars,or white dwarfs)in the Milky Way is essential for understanding the stellar evolution history,the physics of compact objects,and the structure of our Galaxy.Comp...Searching for compact objects(black holes,neutron stars,or white dwarfs)in the Milky Way is essential for understanding the stellar evolution history,the physics of compact objects,and the structure of our Galaxy.Compact objects in binaries with a luminous stellar companion are perfect targets for optical observations.Candidate compact objects can be achieved by monitoring the radial velocities of the companion star.However,most of the spectroscopic telescopes usually obtain stellar spectra at a relatively low efficiency,which makes a sky survey for millions of stars practically impossible.The efficiency of a large-scale spectroscopic survey,the Large Sky Area Multi-Object Fiber Spectroscopy Telescope(LAMOST),presents a specific opportunity to search for compact object candidates,i.e.,simply from the spectroscopic observations.Late-type K/M stars are the most abundant populations in our Galaxy.Owing to the relatively large Keplerian velocities in the close binaries with a K/M-dwarf companion,a hidden compact object could be discovered and followed-up more easily.In this study,compact object candidates with K/Mdwarf companions are investigated with the LAMOST low-resolution stellar spectra.Based on the LAMOST Data Release 5,we obtained a sample of 56 binaries,each containing a K/M-dwarf with a large radial velocity variation △VR>150 km s^(-1).Complemented with the photometric information from the Transiting Exoplanet Survey Satellite,we derived a sample of 35 compact object candidates,among which,the orbital periods of 16 sources were revealed by the light curves.Considering two sources as examples,we confirmed that a compact object existed in the two systems by fitting the radial velocity curve.This study demonstrates the principle and the power of searching for compact objects through LAMOST.展开更多
基金supported by the Project of Science and Technology Commission of Jiading,Shanghai(JDKW-2016-W03)the Scientific Research Projects of the Shanghai Municipal Health Commission for Youths(20204Y0016)+1 种基金the National Natural Science Foundation of China(72174041)。
文摘Access block,known as exit block or boarding,is defined as a situation in which patients who are admitted or planned for admission remain in the emergency department(ED)as they are unable to be transferred to an inpatient unit within a reasonable time frame(no longer than 8 hours).[1,2]Access block often occurs due to insufficient hospital capacity and is a major issue in emergency medicine.[3]
基金Funding for the study was provided by the National Natural Science Foundation of China(Nos.81672699 and 81972726,to Dr.T Yang).
文摘Recurrence is common among patients undergoing hepatic resection for hepatocellular carcinoma(HCC),which greatly limits long-term survival.We aimed to identify predictors and long-term prognosis of early and late recurrence after HCC resection.Methods:Multicenter data of patients who underwent HCC resection between 2002 and 2016 were analyzed.Recurrence was divided into early(≤2 years)and late recurrence(>2 years after surgery).Predictors of early and late recurrence,and prognostic factors of post-recurrence survival(PRS)were identified by univariate and multivariate analyses.Results:Among 1,426 patients,554(38.8%)and 348(24.4%)developed early and late recurrence,respectively.Independent predictors associated with early recurrence included preoperative alpha-fetoprotein level>400μg/L,resection margin<1 cm,and tumor size>5.0 cm,multiplicity,macrovascular and microvascular invasion,and satellites of the initial tumor at the first diagnosis of HCC;independent predictors associated with late recurrence included male,cirrhosis,and tumor size>5.0 cm,multiplicity,macrovascular and microvascular invasion,and satellites of the initial tumor.Patients with early recurrence had a lower likelihood of undergoing potentially curative treatments for recurrence(37.2%vs.48.0%,P<0.001)and a worse median PRS(13.5 vs.36.6 months,P<0.001)vs.patients who had late recurrence.Multivariate analysis revealed that early recurrence and irregular postoperative surveillance were independently associated with worse PRS[hazard ratio(HR)=1.250,95%CI:1.016-1.538,P=0.035;and HR=1.983,95%CI:1.677-2.345,P<0.001].Conclusions:Predictors associated with early and late recurrence after curative resection for patients with HCC were generally same,although several did differ.Patients with late recurrence had better long-term survival than patients with early recurrence.
基金supported by National Natural Science Foundation of China(No.81972726).
文摘Background:A solitary hepatocellular carcinoma(HCC)without macrovascular invasion and distant metastasis,regardless of tumor size,is currently classified as early-stage disease by the latest Barcelona Clinic Liver Cancer(BCLC)staging system.While the preferred treatment is surgical resection,the association of tumor morphology with long-term survival outcomes after liver resection for a solitary huge HCC of≥10 cm has not been defined.Methods:Patients who underwent curative liver resection for a solitary huge HCC were identified from a multicenter database.Preoperative imaging findings were used to define spherical-or ellipsoidal-shaped lesions with smooth edges as balloon-shaped HCCs(BS-HCCs);out-of-shape lesions or lesions of any shape with matt edges were defined as non-balloon-shaped HCCs(NBS-HCCs).The two groups of patients with BS-HCCs and NBS-HCCs were matched in a 1:1 ratio using propensity score matching(PSM).Clinicopathologic characteristics,long-term overall survival(OS)and recurrence-free survival(RFS)were assessed.Results:Among patients with a solitary huge HCC,74 pairs of patients with BS-HCC and NBS-HCC were matched.Tumor pathological features including proportions of microvascular invasion,satellite nodules,and incomplete tumor encapsulation in the BS-HCC group were lower than the NBS-HCC group.At a median follow-up of 50.7 months,median OS and RFS of all patients with a solitary huge HCC after PSM were 27.8 and 10.1 months,respectively.The BS-HCC group had better median OS and RFS than the NBS-HCC group(31.9 vs.21.0 months,P=0.01;and 19.7 vs.6.4 months,P=0.015).Multivariate analyses identified BS-HCC as independently associated with better OS(HR=0.592,P=0.009)and RFS(HR=0.633,P=0.013).Conclusions:For a solitary huge HCC,preoperative imaging on tumor morphology was associated with prognosis following resection.In particular,patients with BS-HCCs had better long-term survival following liver resection versus patients with large NBS-HCCs.
基金supported by the National Key R&D Program of China(Grant No.2021YFA1600401)the National Natural Science Foundation of China(NSFC)(Grant Nos.11925301+10 种基金12033006)supported by the NSFC(Grant Nos.11973002,and 12322303)supported by the NSFC(Grant No.12103041)supported by the NSFC(Grant Nos.11988101,and 11933004)supported by the NSFC(Grant No.U2031117)supported by the NSFC(Grant No.12033004)supported by the NSFC(Grant No.12273029)supported by the NSFC(Grant No.12221003)supported by the NSFC(Grant No.11933008)supported by the NSFC(Grant No.12090044)supported by the NSFC(Grant Nos.12041301,and 12121003)。
文摘The near-Earth(within~100 pc)supernova explosions in the past several million years can cause the global deposition of radioactive elements(e.g.,60Fe)on Earth.The remnants of such supernovae are too old to be easily identified.It is therefore of great interest to search for million-year-old near-Earth neutron stars or black holes,the products of supernovae.However,neutron stars and black holes are challenging to find even in our Solar neighbourhood if they are not radio pulsars or X-ray/γ-ray emitters.Here we report the discovery of one of the nearest(127.7±0.3 pc)neutron star candidates in a detached single-lined spectroscopic binary LAMOST J235456.73+335625.9(hereafter J2354).Utilizing the time-resolved ground-based spectroscopy and space photometry,we find that J2354 hosts an unseen compact object with M_(inv)being 1.4-1.6 M_(⊙).The follow-up Swift ultraviolet(UV)and X-ray observations suggest that the UV and X-ray emission is produced by the visible star rather than the compact object.Hence,J2354 probably harbours a neutron star rather than a hot ultramassive white dwarf.Two-hour exceptionally sensitive radio follow-up observations with Five-hundred-meter Aperture Spherical radio Telescope fail to reveal any pulsating radio signals at the 6σflux upper limit of 12.5μJy.Therefore,the neutron star candidate in J2354 can only be revealed via our time-resolved observations.Interestingly,the distance between J2354 and our Earth can be as close as~50 pc around 2.5 million years(Myrs)ago,as revealed by the Gaia kinematics.Our discovery demonstrates a promising way to unveil the hidden near-Earth neutron stars in binaries by exploring the optical time domain,thereby facilitating understanding of the metal-enrichment history in our Solar neighbourhood.
文摘The paper“Compact object candidates with K/M-dwarf com-panions from LAMOST low-resolution survey”[1]was pub-lished in SCIENCE CHINA Physics,Mechanics&Astronomy(65,229711(2022).doi:10.1007/s11433-021-1809-8).Due to an oversight on our part,some errors were made in the originally published paper.We apologize for these errors and offer the corresponding explanations and corrections for the readers.
基金supported by the National Natural Science Foundation of China(Grant Nos.12103047,11925301,12033006,12005192)the National Key Research and Development Program of China(Grant No.2019YFA0405000)+2 种基金the China Manned Space Project(Grant No.CMS-CSST-2021-B07)the China Postdoctoral Science Foundation(Grant Nos.2019TQ0288,2020TQ0287,2020M672255,2021M702742)the Natural Science Foundation of Henan Province of China(Grant No.212300410290)。
文摘Searching for compact objects(black holes,neutron stars,or white dwarfs)in the Milky Way is essential for understanding the stellar evolution history,the physics of compact objects,and the structure of our Galaxy.Compact objects in binaries with a luminous stellar companion are perfect targets for optical observations.Candidate compact objects can be achieved by monitoring the radial velocities of the companion star.However,most of the spectroscopic telescopes usually obtain stellar spectra at a relatively low efficiency,which makes a sky survey for millions of stars practically impossible.The efficiency of a large-scale spectroscopic survey,the Large Sky Area Multi-Object Fiber Spectroscopy Telescope(LAMOST),presents a specific opportunity to search for compact object candidates,i.e.,simply from the spectroscopic observations.Late-type K/M stars are the most abundant populations in our Galaxy.Owing to the relatively large Keplerian velocities in the close binaries with a K/M-dwarf companion,a hidden compact object could be discovered and followed-up more easily.In this study,compact object candidates with K/Mdwarf companions are investigated with the LAMOST low-resolution stellar spectra.Based on the LAMOST Data Release 5,we obtained a sample of 56 binaries,each containing a K/M-dwarf with a large radial velocity variation △VR>150 km s^(-1).Complemented with the photometric information from the Transiting Exoplanet Survey Satellite,we derived a sample of 35 compact object candidates,among which,the orbital periods of 16 sources were revealed by the light curves.Considering two sources as examples,we confirmed that a compact object existed in the two systems by fitting the radial velocity curve.This study demonstrates the principle and the power of searching for compact objects through LAMOST.