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We investigated decays of ^{51,52,53}K at the ISOLDE Decay Station at CERN in order to understand the mechanism of the ß-delayed neutron-emission (ßn) process. The experiment quantified neutron and γ-ray emission paths for each precursor. We used this information to test the hypothesis, first formulated by Bohr in 1939, that neutrons in the ßn process originate from the structureless "compound nucleus." The data are consistent with this postulate for most of the observed decay paths. The agreement, however, is surprising because the compound-nucleus stage should not be achieved in the studied ß decay due to insufficient excitation energy and level densities in the neutron emitter. In the ^{53}K ßn decay, we found a preferential population of the first excited state in ^{52}Ca that contradicted Bohr's hypothesis. The latter was interpreted as evidence for direct neutron emission sensitive to the structure of the neutron-unbound state. We propose that the observed nonstatistical neutron emission proceeds through the coupling with nearby doorway states that have large neutron-emission probabilities. The appearance of "compound-nucleus" decay is caused by the aggregated small contributions of multiple doorway states at higher excitation energy.
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Using the fusion-evaporation reaction ^{106}Cd(^{58}Ni,4n)^{160}Os and the gas-filled recoil separator SHANS, two new isotopes _{76}^{160}Os and _{74}^{156}W have been identified. The α decay of ^{160}Os, measured with an α-particle energy of 7080(26) keV and a half-life of 201_{-37}^{+58} µs, is assigned to originate from the ground state. The daughter nucleus ^{156}W is a ß^{+} emitter with a half-life of 291_{-61}^{+86} ms. The newly measured α-decay data allow us to derive α-decay reduced widths (δ^{2}) for the N=84 isotones up to osmium (Z=76), which are found to decrease with increasing atomic number above Z=68. The reduction of δ^{2} is interpreted as evidence for the strengthening of the N=82 shell closure toward the proton drip line, supported by the increase of the neutron-shell gaps predicted in theoretical models.
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In the present work, the Doppler Shift Attenuation method (DSAM) was used to analyze the observed lineshapes of transitions from excited states in 45Sc, populated in the reaction 36Ar + 12C at a beam energy of 145 MeV. The interpretation and comparison of the experimental results have been performed with large-scale shell model calculations, involving different interactions like: GX1A, GX1J, FPD6, KB3 and ZBM2. KB3 and FPD6 (present work) interactions in the negative parity states, and in positive parity states ZBM2 are most pre-eminent in reproducing the results, due to the large configuration space describing strong collective effects. Furthermore, the present work also looks at the details of the shell model helping in improving the understanding for the occupancy of orbitals. The present investigation suggests the observation of stronger collectivity for positive parity states over negative parity states with predicted enhanced collectivity of states in 45Sc nucleus.
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Using a novel method of isochronous mass spectrometry, the masses of ^{62}Ge, ^{64}As, ^{66}Se, and ^{70}Kr are measured for the first time, and the masses of ^{58}Zn, ^{61}Ga, ^{63}Ge, ^{65}As, ^{67}Se, ^{71}Kr, and ^{75}Sr are redetermined with improved accuracy. The new masses allow us to derive residual proton-neutron interactions (δV_{pn}) in the N=Z nuclei, which are found to decrease (increase) with increasing mass A for even-even (odd-odd) nuclei beyond Z=28. This bifurcation of δV_{pn} cannot be reproduced by the available mass models, nor is it consistent with expectations of a pseudo-SU(4) symmetry restoration in the fp shell. We performed ab initio calculations with a chiral three-nucleon force (3NF) included, which indicate the enhancement of the T=1 pn pairing over the T=0 pn pairing in this mass region, leading to the opposite evolving trends of δV_{pn} in even-even and odd-odd nuclei.
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The pursuit of minimally invasive biopsy and targeted treatment as well as technical progress have boosted the extensive clinical usages of fine needle puncture cell/tissue acquisition technology in recent years. How to rationally use the limited fine needle puncture materials which are usually minimal and fragmented, while making pathological diagnosis, accomplish the auxiliary tests of immune phenotype, molecular features and other tests required by the clinician, and comprehensively improve the diagnostic benefits of fine needle puncture material is a big challenge facing the pathology community. Up to now, there has been no successful experience that can be learned from abroad. Some suggestions for the further improvement of diagnostic efficacy of fine needle puncture specimens from the aspects of sub-specialty cooperation and comprehensive utilization of the materials are put forward based on the progress trend in pathology and the current situation in China.
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ChinaAsunto(s)
Citodiagnóstico , Patología Clínica , Humanos , Biopsia con Aguja Fina , Biopsia Guiada por ImagenRESUMEN
Dyslipidemia is an important risk factor of atherosclerotic cardiovascular disease (ASCVD). Statins delay the occurrence and development of ASCVD, and reduce the risk of cardiovascular events and death. Due to safety concerns, there exist insufficient use of lipid-lowering agents and a high withdrawal rate of the agents in the elderly. To promote the prevention and treatment of ASCVD, this expert consensus is issued and focuses on the management of dyslipidemia of Chinese elderly basing on the clinical evidence of the use of lipid-lowering drugs by the elderly, and the lipid management guidelines and expert consensus recommendations at home and abroad.
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Aterosclerosis , Enfermedades Cardiovasculares , Dislipidemias , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Anciano , Enfermedades Cardiovasculares/prevención & control , China , LDL-Colesterol , Consenso , Dislipidemias/tratamiento farmacológico , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéuticoRESUMEN
Objective: To explore the effectiveness, safety and cost between urinary follicle stimulating hormone (uFSH) and recombinant follicle stimulating hormone (rFSH) in controlled ovarian stimulation (COS) in China. Methods: Data were collected from 16 reproductive centers in China covering oocytes collection time from May 1, 2015 to June 30, 2018. Eligible patients were over 18 years old, adopting COS with uFSH (uFSH group) or rFSH (rFSH group) as start gonadotropins (Gn), and using in vitro fertilization (IVF) and (or) intracytoplasmic sperm injection for fertilisation, excluding frozen embryo recovery cycle. Generalised estimating equation was used to address the violation of independency assumption between cycles due to multiple IVF cycles for one person and clustering nature of cycles carried out within one center. Controlling variables included age, body mass index, anti-Müllerian hormone level, cause of infertility, ovulation protocol, type of fertilisation, number of embryos transferred, number of days of Gn use. Results: Totally 102 061 cycles met eligibility criteria and were included in the analyses. In terms of effectiveness, after controlling relevant unbalanced baseline characteristics, compared with rFSH group, the high oocyte retrieval (>15 oocytes was considered high retrieval) rate of uFSH group significantly decreased in gonadotropin-releasing hormone agonist protocol (OR=0.642, P<0.01) and in gonadotropin-releasing hormone antagonist protocol (OR=0.556, P=0.001), but the clinical pregnancy rate per transfer cycle and the live birth rate per transfer cycle significantly increased (OR=1.179, OR=1.169, both P<0.01) in both agonist and antagonist protocols. For safety, multiple analysis result demonstrated that in the agonist protocol, compared with rFSH group, the incidence of moderate to severe ovarian hyperstimulation syndrome of uFSH group significantly decreased (OR=0.644, P=0.002). The differences in ectopic pregnancy rate and multiple pregnancy rate between the uFSH and rFSH groups were not significant (P=0.890, P=0.470) in all patients. In terms of cost, compared with rFSH group, the uFSH group had lower total Gn costs for each patient (P<0.01). Conclusion: For patients who underwent COS, uFSH has better safety, and economic profiles over rFSH in China.
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Hormona Folículo Estimulante , Inducción de la Ovulación , Femenino , Fertilización In Vitro/métodos , Hormona Liberadora de Gonadotropina , Gonadotropinas , Humanos , Masculino , Inducción de la Ovulación/métodos , Embarazo , Índice de Embarazo , Estudios Retrospectivos , SemenRESUMEN
The isomer depletion of ^{93m}Mo was recently reported [Chiara et al., Nature (London) 554, 216 (2018)NATUAS0028-083610.1038/nature25483] as the first direct observation of nuclear excitation by electron capture (NEEC). However, the measured excitation probability of 1.0(3)% is far beyond the theoretical expectation. In order to understand the inconsistency between theory and experiment, we produce the ^{93m}Mo nuclei using the ^{12}C(^{86}Kr,5n) reaction at a beam energy of 559 MeV and transport the reaction residues to a detection station far away from the target area employing a secondary beam line. The isomer depletion is expected to occur during the slowdown process of the ions in the stopping material. In such a low γ-ray background environment, the signature of isomer depletion is not observed, and an upper limit of 2×10^{-5} is estimated for the excitation probability. This is consistent with the theoretical expectation. Our findings shed doubt on the previously reported NEEC phenomenon and highlight the necessity and feasibility of further experimental investigations for reexamining the isomer depletion under low γ-ray background.
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Abdomen , Implantación de Prótesis , Hernia , Humanos , Prótesis e Implantes , Resultado del TratamientoRESUMEN
Cutaneous wound is one of the common clinical diseases. Functional materials can provide targeted wound protection and promote wound healing through the structural adjustment and functional integration. Currently, functional materials have been widely used in the field of wound repair, becoming one of the important tools for clinical wound treatment. This paper summarizes the application of functional materials of following categories including hemostasis, antibacterial, anti-inflammation, vascularization, and regulation of wound microenvironment in wound repair.
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Antiinfecciosos , Traumatismos de los Tejidos Blandos , Antibacterianos , Hemostasis , Humanos , Cicatrización de HeridasRESUMEN
Objective: To analyze the survival benefits and treatment related toxic effects of simultaneous integrated boost intensity-modulated radiotherapy (SIB-RT) for non-operative esophageal squamous cell carcinoma patients. Methods: The data of 2 132 ESCC patients who were not suitable for surgery or rejected operation, and underwent radical radiotherapy from 2002 to 2016 in 10 hospitals of Jing-Jin-Ji Esophageal and Esophagogastric Cancer Radiotherapy Oncology Group (3JECROG) were analyzed. Among them, 518 (24.3%) cases underwent SIB (SIB group) and 1 614 (75.7%) cases did not receive SIB (No-SIB group). The two groups were matched with 1â¶2 according to propensity score matching (PSM) method (caliper value=0.02). After PSM, 515 patients in SIB group and 977 patients in No-SIB group were enrolled. Prognosis and treatment related adverse effects of these two groups were compared and the independent prognostic factor were analyzed. Results: The median follow-up time was 61.7 months. Prior to PSM, the 1-, 3-, and 5-years overall survival (OS) rates of SIB group were 72.2%, 42.8%, 35.5%, while of No-SIB group were 74.3%, 41.4%, 31.9%, respectively (P=0.549). After PSM, the 1-, 3-, and 5-years OS rates of the two groups were 72.5%, 43.4%, 36.4% and 75.3%, 41.7%, 31.6%, respectively (P=0.690). The univariate survival analysis of samples after PSM showed that the lesion location, length, T stage, N stage, TNM stage, simultaneous chemoradiotherapy, gross tumor volume (GTV) and underwent SIB-RT or not were significantly associated with the prognosis of advanced esophageal carcinoma patients who underwent radical radiotherapy (P<0.05). Cox model multivariate regression analysis showed lesion location, TNM stage, GTV and simultaneous chemoradiotherapy were independent prognostic factors of advanced esophageal carcinoma patients who underwent radical radiotherapy (P<0.05). Stratified analysis showed that, in the patients whose GTV volume≤50 cm(3), the median survival time of SIB and No-SIB group was 34.7 and 30.3 months (P=0.155), respectively. In the patients whose GTV volume>50 cm(3), the median survival time of SIB and No-SIB group was 16.1 and 20.1 months (P=0.218). The incidence of radiation esophagitis and radiation pneumonitis above Grade 3 in SIB group were 4.3% and 2.5%, significantly lower than 13.1% and 11% of No-SIB group (P<0.001). Conclusions: The survival benefit of SIB-RT in patients with locally advanced esophageal carcinoma is not inferior to non-SIB-RT, but without more adverse reactions, and shortens the treatment time. SIB-RT can be used as one option of the radical radiotherapy for locally advanced esophageal cancer.
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Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Neoplasias de Cabeza y Cuello , Radioterapia de Intensidad Modulada , Neoplasias Gástricas , Quimioradioterapia , Análisis de Datos , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/radioterapia , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Humanos , Estudios RetrospectivosRESUMEN
A new α-emitting isotope ^{214}U, produced by the fusion-evaporation reaction ^{182}W(^{36}Ar,4n)^{214}U, was identified by employing the gas-filled recoil separator SHANS and the recoil-α correlation technique. More precise α-decay properties of even-even nuclei ^{216,218}U were also measured in the reactions of ^{40}Ar, ^{40}Ca beams with ^{180,182,184}W targets. By combining the experimental data, improved α-decay reduced widths δ^{2} for the even-even Po-Pu nuclei in the vicinity of the magic neutron number N=126 are deduced. Their systematic trends are discussed in terms of the N_{p}N_{n} scheme in order to study the influence of proton-neutron interaction on α decay in this region of nuclei. It is strikingly found that the reduced widths of ^{214,216}U are significantly enhanced by a factor of two as compared with the N_{p}N_{n} systematics for the 84≤Z≤90 and N<126 even-even nuclei. The abnormal enhancement is interpreted by the strong monopole interaction between the valence protons and neutrons occupying the π1f_{7/2} and ν1f_{5/2} spin-orbit partner orbits, which is supported by the large-scale shell model calculation.
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Objective: To evaluate the survival and prognostic factors of radiotherapy in patient with â £ stage esophageal squamous carcinoma treated with radiation or chemoradiation. Methods: The medical records of 608 patients with stage â £ esophageal squamous cell carcinoma who met the inclusion criteria in 10 medical centers in China from 2002 to 2016 were retrospectively analyzed. The overall survival and prognostic factors of all patients at 1, 3 and 5 years were analyzed. Results: The 1-, 3-, 5- year overall survival (OS) rates was 66.7%, 29.5% and 24.3% in stage â £A patients, and 58.8%, 29.0% and 23.5% in stage â £B patients. There was no statistical difference between the two groups (P=0.255). Univariate analysis demonstrated that the length of lesion, treatment plan, planned tumor target volume (PGTV) dose, subsequent chemotherapy, and degrees of anemia, radiation esophagitis, radiation pneumonia were related to the prognoses of patients with â £ stage esophageal carcinomas after radiotherapy and chemotherapy (P<0.05). Multivariate analysis demonstrated that PGTV dose (OR=0.693, P=0.004), radiation esophagitis (OR=0.867, P=0.038), and radiation pneumonia (OR=1.181, P=0.004) were independent prognostic factors for OS. Conclusions: For patients with stage â £ esophageal squamous cell carcinoma, chemoradiotherapy followed by sequential chemotherapy is recommended, which can extend the total survival and improve the prognosis of the patients. PGTV dose more than 60 Gy has better efficacy.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioradioterapia/métodos , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/radioterapia , Carcinoma de Células Escamosas de Esófago/tratamiento farmacológico , Carcinoma de Células Escamosas de Esófago/radioterapia , China/epidemiología , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Carcinoma de Células Escamosas de Esófago/mortalidad , Carcinoma de Células Escamosas de Esófago/patología , Humanos , Estadificación de Neoplasias , Radioterapia de Intensidad Modulada/métodos , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Objective: To investigate the clinical and immunological features of cardiac involvement in patients with dermatomyositis (DM). Methods: Data of 271 adult patients with DM diagnosed in the Department of Rheumatology and Immunology, Peking University People's Hospital from 2003 to 2018 were collected retrospectively and analyzed statistically. Results: The occurrence of cardiac involvement in DM was 15.9% (43/271). Main feature of cardiac involvement in DM was elevated cardiac troponin I (cTnI). The most common abnormalities of ECG were T wave abnormality (27.9%, 12/43), sinus tachycardia (16.3%,7/43), ST-T change (14%, 6/43) and right bundle branch block (7%, 3/43). The common manifestations of echocardiography were left ventricular diastolic dysfunction (23.3%, 10/43) and pericardial effusion (23.3%, 10/43). As compared with DM patients without cardiac involvement, DM patients with cardiac damage were more likely to have rapidly progressive interstitial lung disease (ILD), skin damage, anemia, elevated creatine kinase, decreased C3 and serum albumin (P<0.05). Positive anti-Ro-52 antibody and Jo-1 antibody were detected more common in DM with cardiac involvement(P<0.05). Conclusions: Cardiac damage is common complication of DM. Manifestations of cardiac damaging are varied. Rapid progressive ILD and positive Jo-1 and Ro-52 antibodies are more common in this group. Clinicians should improve the awareness of cardiac involvement in DM patients.
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Dermatomiositis , Adulto , Ecocardiografía , Humanos , Enfermedades Pulmonares Intersticiales , Estudios RetrospectivosRESUMEN
OBJECTIVE: Uric acid is considered a biomarker for cardiovascular risk. Only a few studies have investigated the effect of aspirin on serum uric acid (SUA) levels with contradictory results. The present study evaluated the effect of aspirin on SUA levels in Chinese individuals over 60 years of age. PATIENTS AND METHODS: Subjects over 60 with coronary artery disease or multiple cardiovascular risk factors were enrolled in a multicentre randomized clinical trial. Eligible subjects were randomized to receive 50 mg or 100 mg aspirin daily. Levels of arachidonic acid-induced platelet aggregation performed by light transmission aggregometry (LTA-AA) and SUA were measured at randomization and two weeks thereafter. In this subanalysis, subjects without aspirin use prior to enrolment were chosen. RESULTS: A total of 446 subjects were analysed, of which 151 subjects took 50 mg aspirin, and 295 took 100 mg aspirin. Hyperuricaemia was present in 23.3% (104/446) of subjects at baseline. LTA-AA levels were significantly reduced in subjects after taking aspirin for two weeks (both 50 mg and 100 mg, p < 0.001). SUA levels were decreased after aspirin administration (311 µmol/L vs. 302 µmol/L, p < 0.001). Further analysis showed SUA levels were unchanged in normouricaemic subjects (284 µmol/L vs. 280 µmol/L, p > 0.05), while slightly decreased in hyperuricaemic subjects (429 µmol/L vs. 392 µmol/L, p < 0.001). CONCLUSIONS: Our study showed that both 50 mg and 100 mg aspirin significantly inhibited platelet aggregation. Aspirin treatment for two weeks showed no hyperuricaemic effect in people over 60. SUA levels were unchanged after taking aspirin in normouricaemic subjects but decreased in hyperuricaemic subjects. This trial was registered at www. chictr.org.cn as ChiCTR1800018517.
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Pueblo Asiatico , Aspirina/administración & dosificación , Aspirina/farmacología , Enfermedades Cardiovasculares/sangre , Ácido Úrico/sangre , Administración Oral , Anciano , Aspirina/sangre , Enfermedades Cardiovasculares/tratamiento farmacológico , China , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Agregación Plaquetaria/efectos de los fármacos , Factores de RiesgoRESUMEN
Objective: To evaluate the prognostic factors of T1-2N0M0 esophageal squamous cell carcinoma (ESCC) treated with definitive radiotherapy. Methods: The clinical data of 196 patients with T1-2N0M0 ESCC who were treated with definitive radiotherapy in 10 hospitals were retrospectively analyzed. All sites were members of Jing-Jin-Ji Esophageal and Esophagogastric Cancer Radiotherapy Oncology Group (3JECROG). Radiochemotherapy were applied to 78 patients, while the other 118 patients received radiotherapy only. 96 patients were treated with three-dimensional conformal radiotherapy (3DCRT) and 100 treated with intensity-modulated radiotherapy (IMRT). The median dose of plan target volume(PTV) and gross target volume(GTV) were both 60 Gy. The median follow-up time was 59.2 months. Log rank test and Cox regression analysis were used for univariat and multivariate analysis, respectively. Results: The percentage of normal lung receiving at least 20 Gy (V(20)) was (18.65±7.20)%, with average dose of (10.81±42.05) Gy. The percentage of normal heart receiving at least 30 Gy (V(30)) was (14.21±12.28)%. The maximum dose of exposure in spinal cord was (39.65±8.13) Gy. The incidence of radiation pneumonia and radiation esophagitis were 14.80%(29/196) and 65.82%(129/196), respectively. The adverse events were mostly grade 1-2, without grade 4 toxicity. Median overall survival (OS) and progression-free survival (PFS) were 70.1 months and 62.3 months, respectively. The 1-, 3- and 5-year OS rates of all patients were 75.1%ã57.4% and 53.2%, respectively. The 1-, 3- and 5-year PFS rates were 75.1%ã57.4% and 53.2%, respectively. Multivariate analysis demonstrated that patients'age (HR=1.023, P=0.038) and tumor diameter (HR=1.243, P=0.028)were the independent prognostic factors for OS, while tumor volume were the independent prognostic factor for PFS. Conclusions: Definitive radiotherapy is a promising therapeutic method in patients with T1-2N0M0 ESCC. Patients' age, tumor diameter and tumor volume may impact patients' prognosis.