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The proton is one of the main building blocks of all visible matter in the Universe1. Among its intrinsic properties are its electric charge, mass and spin2. These properties emerge from the complex dynamics of its fundamental constituents-quarks and gluons-described by the theory of quantum chromodynamics3-5. The electric charge and spin of protons, which are shared among the quarks, have been investigated previously using electron scattering2. An example is the highly precise measurement of the electric charge radius of the proton6. By contrast, little is known about the inner mass density of the proton, which is dominated by the energy carried by gluons. Gluons are hard to access using electron scattering because they do not carry an electromagnetic charge. Here we investigated the gravitational density of gluons using a small colour dipole, through the threshold photoproduction of the J/ψ particle. We determined the gluonic gravitational form factors of the proton7,8 from our measurement. We used a variety of models9-11 and determined, in all cases, a mass radius that is notably smaller than the electric charge radius. In some, but not all cases, depending on the model, the determined radius agrees well with first-principle predictions from lattice quantum chromodynamics12. This work paves the way for a deeper understanding of the salient role of gluons in providing gravitational mass to visible matter.
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The visible world is founded on the proton, the only composite building block of matter that is stable in nature. Consequently, understanding the formation of matter relies on explaining the dynamics and the properties of the proton's bound state. A fundamental property of the proton involves the response of the system to an external electromagnetic field. It is characterized by the electromagnetic polarizabilities1 that describe how easily the charge and magnetization distributions inside the system are distorted by the electromagnetic field. Moreover, the generalized polarizabilities2 map out the resulting deformation of the densities in a proton subject to an electromagnetic field. They disclose essential information about the underlying system dynamics and provide a key for decoding the proton structure in terms of the theory of the strong interaction that binds its elementary quark and gluon constituents. Of particular interest is a puzzle in the electric generalized polarizability of the proton that remains unresolved for two decades2. Here we report measurements of the proton's electromagnetic generalized polarizabilities at low four-momentum transfer squared. We show evidence of an anomaly to the behaviour of the proton's electric generalized polarizability that contradicts the predictions of nuclear theory and derive its signature in the spatial distribution of the induced polarization in the proton. The reported measurements suggest the presence of a new, not-yet-understood dynamical mechanism in the proton and present notable challenges to the nuclear theory.
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When protons and neutrons (nucleons) are bound into atomic nuclei, they are close enough to feel significant attraction, or repulsion, from the strong, short-distance part of the nucleon-nucleon interaction. These strong interactions lead to hard collisions between nucleons, generating pairs of highly energetic nucleons referred to as short-range correlations (SRCs). SRCs are an important but relatively poorly understood part of nuclear structure1-3, and mapping out the strength and the isospin structure (neutron-proton (np) versus proton-proton (pp) pairs) of these virtual excitations is thus critical input for modelling a range of nuclear, particle and astrophysics measurements3-5. Two-nucleon knockout or 'triple coincidence' reactions have been used to measure the relative contribution of np-SRCs and pp-SRCs by knocking out a proton from the SRC and detecting its partner nucleon (proton or neutron). These measurements6-8 have shown that SRCs are almost exclusively np pairs, but they had limited statistics and required large model-dependent final-state interaction corrections. Here we report on measurements using inclusive scattering from the mirror nuclei hydrogen-3 and helium-3 to extract the np/pp ratio of SRCs in systems with a mass number of three. We obtain a measure of the np/pp SRC ratio that is an order of magnitude more precise than previous experiments, and find a marked deviation from the near-total np dominance observed in heavy nuclei. This result implies an unexpected structure in the high-momentum wavefunction for hydrogen-3 and helium-3. Understanding these results will improve our understanding of the short-range part of the nucleon-nucleon interaction.
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The electromagnetic form factors of the proton and neutron encode information on the spatial structure of their charge and magnetization distributions. While measurements of the proton are relatively straightforward, the lack of a free neutron target makes measurements of the neutron's electromagnetic structure more challenging and more sensitive to experimental or model-dependent uncertainties. Various experiments have attempted to extract the neutron form factors from scattering from the neutron in deuterium, with different techniques providing different, and sometimes large, systematic uncertainties. We present results from a novel measurement of the neutron magnetic form factor using quasielastic scattering from the mirror nuclei ^{3}H and ^{3}He, where the nuclear effects are larger than for deuterium but expected to largely cancel in the cross-section ratios. We extracted values of the neutron magnetic form factor for low-to-modest momentum transfer, 0.6
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With the accumulation of research evidence and clinical experience, an increasing number of patients benefit from vascular recanalization therapies. Although successful recanalization of the occluded artery has been achieved, neurological deficits persist after endovascular treatment, which defined as"futile reperfusion". Compared with the successful recanalization, successful reperfusion predicts final infarct size and clinical outcome more accurately. At present, the known influencing factors of futile reperfusion include older age, female, high baseline National Institute of Health stroke scale (NIHSS) score, hypertension, diabetes, atrial fibrillation, reperfusion treatment strategy, large infarction core volume, and collateral circulation status. The incidence of futile reperfusion in China is significantly higher than that in western population. However, few studies focused on its mechanism and influencing factors. To date, many clinical studies have attempted to reduce the occurrence of futile recanalization regarding antiplatelet therapy, blood pressure management and treatment process improvement. However, only one effective measure has been achieved in blood pressure management: systolic blood pressure control below 120 mmHg (1 mmHg=0.133 kPa) should be avoided after successful recanalization. Therefore, future studies are warranted to promote the establishment and maintenance of collateral circulation, as well as neuroprotective therapy.
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Isquemia Encefálica , Procedimientos Endovasculares , Accidente Cerebrovascular Isquémico , Accidente Cerebrovascular , Humanos , Femenino , Accidente Cerebrovascular/terapia , Atención , China , Resultado del Tratamiento , Isquemia Encefálica/terapia , Estudios RetrospectivosRESUMEN
Bromadiolone is still often used in life as a poisonous rodent agent. Bromadiolone poisoning is often manifested as coagulation dysfunction, resulting in organ bleeding, including cerebral hemorrhage, intestinal bleeding, abdominal hemorrhage, etc. At present, no case of intestinal necrosis caused by bromadiolone poisoning have been reported. This article reviewed one case of intestinal necrosis and severe coagulation dysfunction, and finally confirmed bromadiolone poisoning by poison detection. The patient recovered and was discharged after surgery, vitamin K injection, plasma transfusion and other treatment methods.
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4-Hidroxicumarinas , Trastornos de la Coagulación Sanguínea , Intoxicación , Rodenticidas , Humanos , Trastornos de la Coagulación Sanguínea/inducido químicamente , Transfusión de Componentes Sanguíneos , Hemorragia , Necrosis , PlasmaRESUMEN
Freon is widely used in daily life, which is usually absorbed through the respiratory tract and causes clinical manifestations mainly in the cardiovascular system and neurological damage. Now, we analyze the clinical data, diagnosis, treatment and prognosis of two cases of freon poisoning in Affiliated Dongyang People's Hospital of Wenzhou Medical University to improve the clinicians' understanding of freon poisoning and to avoid missed diagnosis and misdiagnosis.
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Clorofluorocarburos , Intoxicación , Humanos , PronósticoRESUMEN
The ratio of the nucleon F_{2} structure functions, F_{2}^{n}/F_{2}^{p}, is determined by the MARATHON experiment from measurements of deep inelastic scattering of electrons from ^{3}H and ^{3}He nuclei. The experiment was performed in the Hall A Facility of Jefferson Lab using two high-resolution spectrometers for electron detection, and a cryogenic target system which included a low-activity tritium cell. The data analysis used a novel technique exploiting the mirror symmetry of the two nuclei, which essentially eliminates many theoretical uncertainties in the extraction of the ratio. The results, which cover the Bjorken scaling variable range 0.19
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We report high-precision measurements of the deeply virtual Compton scattering (DVCS) cross section at high values of the Bjorken variable x_{B}. DVCS is sensitive to the generalized parton distributions of the nucleon, which provide a three-dimensional description of its internal constituents. Using the exact analytic expression of the DVCS cross section for all possible polarization states of the initial and final electron and nucleon, and final state photon, we present the first experimental extraction of all four helicity-conserving Compton form factors (CFFs) of the nucleon as a function of x_{B}, while systematically including helicity flip amplitudes. In particular, the high accuracy of the present data demonstrates sensitivity to some very poorly known CFFs.
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We present new precision measurements of the elastic electron-proton scattering cross section for momentum transfer (Q^{2}) up to 15.75 (GeV/c)^{2}. Combined with existing data, these provide an improved extraction of the proton magnetic form factor at high Q^{2} and double the range over which a longitudinal or transverse separation of the cross section can be performed. The difference between our results and polarization data agrees with that observed at lower Q^{2} and attributed to hard two-photon exchange (TPE) effects, extending to 8 (GeV/c)^{2} the range of Q^{2} for which a discrepancy is established at >95% confidence. We use the discrepancy to quantify the size of TPE contributions needed to explain the cross section at high Q^{2}.
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In order to investigate developmental coordination disorder (DCD) of kindergarten children in Zhejiang province, 200 ordinary kindergartens were randomly selected by stratified random sampling in 11 prefecture-level cities of Zhejiang Province, and 38 900 children from 1 000 classes in each grade were then randomly selected into the study from June 2019 to December 2019. The Little DCD Questionnaire and a self-designed questionnaire were used to screen the DCD of those children. There were 36 807 valid questionnaires, and 6.50% (2 391/36 807) of them were positive results. The results showed that boy, age ≤5 years, overweight or obesity, left handedness, comorbidity with motor or developmental disorders and premature infants were risk factors of DCD in children. As for parents and families, maternal gestational age<20 years, maternal overweight or obesity before pregnancy, low-middle level education of parents, direct family and low income of family were also associated with DCD in children. Therefore, it is necessary to conduct early prevention and intervention strategies targeting on identified risk factors among relevant population.
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Trastornos de la Destreza Motora , Sobrepeso , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Trastornos de la Destreza Motora/epidemiología , Obesidad , Embarazo , Factores de Riesgo , Instituciones Académicas , Adulto JovenRESUMEN
Brown planthopper (BPH), white-backed planthopper (WBPH) and small brown planthopper (SBPH), are the closely related rice pests that perform differentially on wheat plants. Using fecundity as a fitness measure, we found that SBPH well-adapted on wheat plants, followed by WBPH, while BPH had the worst performance. The transcriptomic responses of SBPH and BPH to wheat plants have been compared previously. To understand the different fitness mechanisms of three planthoppers, this study first investigated the transcriptomic responses of WBPH to rice and wheat plants. Genes involved in detoxification, transportation and proteasome were significantly enriched in WBPH in response to different diets. Moreover, comparative analysis demonstrated that most co-regulated genes in BPH and SBPH showed different expression changes; whereas most co-regulated genes in BPH and WBPH exhibited similar expression changes. Subsequently, this study also investigated the influences of host plants on the bacterial community of three planthoppers. The three planthoppers harboured distant diversity of bacterial communities. However, there was no dramatic change in bacterial diversity or relative abundance in planthoppers colonized on different hosts. This study illustrates generic and species-specific changes of three rice planthoppers in response to different plants, which deepen our understanding towards the host fitness for planthopper species.
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Microbioma Gastrointestinal , Hemípteros/fisiología , Oryza , Transcriptoma , Triticum , Animales , Dieta , Hemípteros/genética , Hemípteros/microbiología , Especificidad de la EspecieRESUMEN
We report measurements of the exclusive neutral pion electroproduction cross section off protons at large values of x_{B} (0.36, 0.48, and 0.60) and Q^{2} (3.1 to 8.4 GeV^{2}) obtained from Jefferson Lab Hall A experiment E12-06-014. The corresponding structure functions dσ_{T}/dt+εdσ_{L}/dt, dσ_{TT}/dt, dσ_{LT}/dt, and dσ_{LT^{'}}/dt are extracted as a function of the proton momentum transfer t-t_{min}. The results suggest the amplitude for transversely polarized virtual photons continues to dominate the cross section throughout this kinematic range. The data are well described by calculations based on transversity generalized parton distributions coupled to a helicity flip distribution amplitude of the pion, thus providing a unique way to probe the structure of the nucleon.
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Quasielastic ^{12}C(e,e^{'}p) scattering was measured at spacelike 4-momentum transfer squared Q^{2}=8, 9.4, 11.4, and 14.2 (GeV/c)^{2}, the highest ever achieved to date. Nuclear transparency for this reaction was extracted by comparing the measured yield to that expected from a plane-wave impulse approximation calculation without any final state interactions. The measured transparency was consistent with no Q^{2} dependence, up to proton momenta of 8.5 GeV/c, ruling out the quantum chromodynamics effect of color transparency at the measured Q^{2} scales in exclusive (e,e^{'}p) reactions. These results impose strict constraints on models of color transparency for protons.
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Fluorine is one of the most interesting elements in nuclear astrophysics, where the ^{19}F(p,α)^{16}O reaction is of crucial importance for Galactic ^{19}F abundances and CNO cycle loss in first generation Population III stars. As a day-one campaign at the Jinping Underground Nuclear Astrophysics experimental facility, we report direct measurements of the essential ^{19}F(p,αγ)^{16}O reaction channel. The γ-ray yields were measured over E_{c.m.}=72.4-344 keV, covering the Gamow window; our energy of 72.4 keV is unprecedentedly low, reported here for the first time. The experiment was performed under the extremely low cosmic-ray-induced background environment of the China JinPing Underground Laboratory, one of the deepest underground laboratories in the world. The present low-energy S factors deviate significantly from previous theoretical predictions, and the uncertainties are significantly reduced. The thermonuclear ^{19}F(p,αγ)^{16}O reaction rate has been determined directly at the relevant astrophysical energies.
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BACKGROUND: The aim of this study was to evaluate whether adjuvant chemotherapy is associated with improved survival in patients with resectable gastric neuroendocrine carcinomas (G-NECs) or mixed adenoneuroendocrine carcinomas (G-MANECs). METHODS: The study included patients with G-NECs or G-MANECs who underwent surgery in one of 21 centres in China between 2004 and 2016. Propensity score matching analysis was used to reduce selection bias, and overall survival (OS) in different treatment groups was estimated by the Kaplan-Meier method. RESULTS: In total, 804 patients with resectable G-NECs or G-MANECs were included, of whom 490 (60·9 per cent) received adjuvant chemotherapy. After propensity score matching, OS in the chemotherapy group was similar to that in the no-chemotherapy group. Among patients with G-NECs, survival in the fluorouracil (5-FU)-based chemotherapy group and the non-5-FU-based chemotherapy group was similar to that in the no-chemotherapy group. Similarly, etoposide plus cisplatin or irinotecan plus cisplatin was not associated with better OS in patients with G-NECs. Among patients with G-MANECs, OS in the non-5-FU-based chemotherapy group was worse than that in the no-chemotherapy group. Patients with G-MANECs did not have better OS when platinum-based chemotherapy was used. CONCLUSION: There was no survival benefit in patients who received adjuvant chemotherapy for G-NECs or G-MANECs.
ANTECEDENTES: El objetivo de este estudio fue evaluar si la quimioterapia adyuvante mejoraba la supervivencia en pacientes con carcinomas gástricos resecables neuroendocrinos (gastric neuroendocrine carcinomas, G-NECs) y carcinomas adenoneuroendocrinos mixtos (mixed adenoneuroendocrine carcinomas, G-MANECs). MÉTODOS: Se incluyeron pacientes con G-NECs y G-MANECs tratados quirúrgicamente en 21 centros en China entre 2004 y 2016. Se utilizó un análisis de emparejamiento por puntaje de propensión para reducir el sesgo de selección y el método de Kaplan-Meier para estimar la supervivencia global (overall survival, OS) de los pacientes en los diferentes grupos de tratamiento. RESULTADOS: En total, se incluyeron en el estudio 804 pacientes con G-NECs y G-MANECs resecables y 490 pacientes (60,9%) recibieron quimioterapia adyuvante. Después del emparejamiento por puntaje de propensión, la OS del grupo con quimioterapia fue similar a la del grupo sin quimioterapia. En los pacientes con G-NECs, la supervivencia en los grupos con quimioterapia basada en 5-FU (fluorouracilo) y de quimioterapia sin 5-FU fue similar a la del grupo sin quimioterapia. Asimismo, la combinación de etopósido y cisplatino o de irinotecán y cisplatino no se asoció con una mejor OS en pacientes con G-NECs. En pacientes con G-MANECs, la OS del grupo con quimioterapia sin 5-FU fue peor que la del grupo sin quimioterapia. Los pacientes con G-MANECs no presentaron una mejor OS cuando se administró quimioterapia basada en platinos. CONCLUSIÓN: La administración de quimioterapia adyuvante en pacientes con G-NECs y G-MANECs no mejoró la supervivencia.
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Carcinoma Neuroendocrino/tratamiento farmacológico , Quimioterapia Adyuvante , Neoplasias Gástricas/tratamiento farmacológico , Anciano , Antimetabolitos Antineoplásicos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma Neuroendocrino/mortalidad , Carcinoma Neuroendocrino/cirugía , Quimioterapia Adyuvante/métodos , Quimioterapia Adyuvante/mortalidad , Cisplatino/administración & dosificación , Cisplatino/uso terapéutico , Etopósido/administración & dosificación , Etopósido/uso terapéutico , Femenino , Fluorouracilo/uso terapéutico , Humanos , Irinotecán/administración & dosificación , Irinotecán/uso terapéutico , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Puntaje de Propensión , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/cirugía , Análisis de SupervivenciaRESUMEN
We measure ^{2}H(e,e^{'}p)n cross sections at 4-momentum transfers of Q^{2}=4.5±0.5 (GeV/c)^{2} over a range of neutron recoil momenta p_{r}, reaching up to â¼1.0 GeV/c. We obtain data at fixed neutron recoil angles θ_{nq}=35°, 45°, and 75° with respect to the 3-momentum transfer q[over â]. The new data agree well with previous data, which reached p_{r}â¼500 MeV/c. At θ_{nq}=35° and 45°, final state interactions, meson exchange currents, and isobar currents are suppressed and the plane wave impulse approximation provides the dominant cross section contribution. We compare the new data to recent theoretical calculations, where we observe a significant discrepancy for recoil momenta p_{r}>700 MeV/c.
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We report the first measurement of the (e,e^{'}p) three-body breakup reaction cross sections in helium-3 (^{3}He) and tritium (^{3}H) at large momentum transfer [⟨Q^{2}⟩≈1.9 (GeV/c)^{2}] and x_{B}>1 kinematics, where the cross section should be sensitive to quasielastic (QE) scattering from single nucleons. The data cover missing momenta 40≤p_{miss}≤500 MeV/c that, in the QE limit with no rescattering, equals the initial momentum of the probed nucleon. The measured cross sections are compared with state-of-the-art ab initio calculations. Overall good agreement, within ±20%, is observed between data and calculations for the full p_{miss} range for ^{3}H and for 100≤p_{miss}≤350 MeV/c for ^{3}He. Including the effects of rescattering of the outgoing nucleon improves agreement with the data at p_{miss}>250 MeV/c and suggests contributions from charge-exchange (SCX) rescattering. The isoscalar sum of ^{3}He plus ^{3}H, which is largely insensitive to SCX, is described by calculations to within the accuracy of the data over the entire p_{miss} range. This validates current models of the ground state of the three-nucleon system up to very high initial nucleon momenta of 500 MeV/c.
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The aim of the study was to explore the effect of lipoxin A4 (LXA4) on lung injury in sepsis rats through the p38/mitogen-activated protein kinase (MAPK) signaling pathway. Sprague-Dawley rats were used for the study. The rat model of sepsis-induced acute lung injury was established via cecal ligation (Sepsis group, n=20). LXA4 (0.1 mg/kg) was injected at 6 h after modeling (Treatment group, n=20), and a The Control group (n=20) was also set up. The 7-day survival rate was 100% in The Control group, and LXA4 raised the survival rate of rats in the Sepsis group from 40% to 60% (P<0.01). Alveolar fluid clearance (AFC) significantly declined and the wet/dry weight (W/D) ratio of lung tissues rose remarkably in the Sepsis group compared with those in the Control group, while LXA4 restored AFC and reduced the W/D ratio of lung tissues (P<0.05), suggesting that LXA4 treatment reduces lung fluids and partially enhances AFC, thus lowering the W/D ratio of lung. The total cell count, polymorphonuclear neutrophils (PMN) percentage and concentration of tumor necrosis factor-α (TNF-α) and interleukin (IL)-6 in bronchoalveolar lavage fluid (BALF) were obviously increased in the Sepsis group compared with those in the Control group, while they were markedly decreased in the Treatment group (P<0.05). The activity of myeloperoxidase (MPO) in lung tissue homogenate was evidently higher in the Sepsis group than that in The Control group, while it was notably lower in the Treatment group than that in the Sepsis group after LXA4 treatment (P<0.05). Moreover, it was observed microscopically that the morphology of lung tissues was intact in the Control group. Finally, the results of Western blotting manifested that the p-p38/ MAPK protein expression was remarkably increased in the Sepsis group, indicating the activation of the p38/MAPK pathway, while it was remarkably decreased in the Treatment group, indicating the inhibited activity of the pathway (P<0.05). LXA4 has an anti-inflammatory effect on sepsis rats with lung injury, and such effect is related to the p38/MAPK signaling pathway.
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Sepsis , Animales , Lipoxinas , Pulmón , Ratas , Ratas Sprague-Dawley , Sepsis/tratamiento farmacológico , Transducción de SeñalRESUMEN
Objectve: To evaluate the relationship of Parkinson's disease(PD) patients' sleep quality and depression with burden, quality of life, and depression of their caregivers. Methods: A total of 120 PD patients (68 males and 52 females) and their caregivers (48 males and 72 females) from Changshu Hospital Affiliated to Nanjing University of Chinese Medicine between January 2017 and June 2019 were recruited. Patients' sleep quality, depression and quality of life was evaluated. Burden, quality of life, quality of sleep, and depression of caregivers were assessed by the Caregivers Burden Questionnaire (CBI), Health Survey Brief (SF-36), Pittsburgh Sleep Quality Index (PQS1) and Hamilton Depression Scale (HAMD), meanwhile, the correlation between relevant factors was analyzed. Results: The CBI of caregivers was positively correlated with the unified Parkinson's disease rating scale (UPDRS)-â ¢ scores of PD patients (r=0.436, P<0.05). The CBI, SF-36GH, SF-36MH, HAMD and PSQI scores of caregivers were positively correlated with Parkinson's disease sleep scale (PDSS) scores of PD patients (r=0.546, 0.762, 0.528, 0.562 and 0.522, respectively, all P<0.01). The caregiver's CBI score was positively correlated with PD patients' Epworth sleepiness score (ESS) score (r=0.442, P<0.05), and caregiver's CBI, SF-36GH, SF-36MH, HAMD, PSQI scores were positively correlated with PD patients' HAMD scores (r=0.765, 0.813, 0.635, 0.884 and 0.601, respectively, all P<0.01). The caregiver's CBI score was positively correlated with the PDQ-39 score of PD patients (r=0.834, 0.452, 0.463, 0.421 and 0.387, respectively, all P<0.05). Multiple regression analysis indicated that the caregiver's CBI score was significantly correlated with the patient's PDQ-39, PDSS and HAMD scores (r=0.512, 0.645 and 0.635, respectively, all P<0.01), and the caregiver's SF-36GH score was significantly correlated with the patient's PDQ-39, PDSS and HAMD scores (r=0.452, 0.682 and 0.506, respectively, all P<0.01). The caregiver's SF-36MH score was significantly correlated with the patient's PDQ-39, PDSS and HAMD scores (r=0.426, 0.608 and 0.598, respectively, all P<0.01). There was significant correlations between the caregiver's HAMD score and the patient's PDSS and HAMD scores (r=0.568 and 0.496, both P<0.01), and the PSQI score of the caregiver was significantly correlated with the PDSS and HAMD scores of the patient (r=0.532 and 0.461, both P<0.01). Conclusions: This current study underscores the presence of a significant relationship of patient's sleep quality with caregiver's burden, quality of life, depression and sleep quality. Specifically, sleep quality and depression of the patients are independent predictors for burden, quality of life and sleep quality of the caregivers.