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We aimed to explore the association between blood pressure, intracranial atherosclerotic stenosis (ICAS) risks and ICAS burden in the Chinese population.A retrospective hospital-based multi-center case-control study with large sample size was conducted. 1055 ICAS patients and 1296 non-ICAS subjects with complete clinical information and intracranial artery evaluation were identified between 2014 and 2019. Cerebral arteries were evaluated by magnetic resonance angiography, and/or computed tomography, and/or digital subtraction angiography. Two or more neurologists were involved in reading and assessment of images. The association between ICAS and burden of ICAS with blood pressure was evaluated with univariate logistic models and multivariate logistic models.With every increase of 10 mmHg in systolic blood pressure, diastolic blood pressure and pulse pressure, the odds of ICAS increased by 32%, 28% and 35% in multivariate analysis, respectively (odds ratio = 1.32, 1.28, and 1.35 respectively, all p 0.001). Similarly, every increment of 10 mmHg in systolic blood pressure and pulse pressure was associated with an increased risk of ICAS burden (each odds ratio = 1.08, p 0.05).Systolic blood pressure, diastolic blood pressure, and pulse pressure were associated with the risk of ICAS in a dose-response manner. Moreover, higher systolic blood pressure and pulse pressure could lead to higher ICAS burdens.

With the development of the Internet era, urban logistics distribution increases. At the same time, the state vigorously promotes the development of the new energy automobile industry and the continuous strengthening of people’s awareness of environmental protection, new energy vehicles began to be favored by logistics enterprises. From the analysis of the national support policy for new energy vehicles, the development of new energy vehicles in recent years and the TCO calculation of their cost advantages, this paper clarifies that new energy vehicles will occupy the mainstream position in urban logistics distribution.

A novel topology circuit of active compensation was discussed to be used to manage negative sequence caused by locomotive load in electrified railway. The main circuit used a three-phase two-leg compensator as active elements of shunt hybrid active compensator topology. The number of switch device in this topology was reduced by comparing with three-phase full-bridge active inverter and the cost was lower. The simulation model was developed with SIMULINK. The simulating results indicates that the shunt hybrid active compensator can restrain the problem of negative sequence which generated by locomotive load, and reduces the effect of reactive power, negative sequence, improves electric energy quality and verifies the correctness of the proposed structure and control method.

Background: To study the characters of high-frequency oscillations (HFOs) in the seizure onset zones (SOZ) and the nonseizure onset zones (NSOZ) in the electrocorticography (ECoG) of patients with neocortical epilepsy. Methods: Only patients with neocortical epilepsy who were seizure-free after surgery as determined with ECoG were included. We selected patients with normal magnetic resonance imaging before surgery in order to avoid the influence of HFOs by other lesions. Three minutes preictal and 10 min interictal ECoG as recorded in 39 channels in the SOZ and 256 channels in the NSOZ were analyzed. Ripples and fast ripples (FRs) were analyzed by Advanced Source Analysis software (ASA, The Netherlands). Average duration of HFOs was analyzed in SOZ and NSOZ separately. Results: For ripples, the permillage time occupied by HFOs was 0.83 in NSOZ and 1.17 in SOZ during the interictal period. During preictal period, they were 2.02 in NSOZ and 7.93 in SOZ. For FRs, the permillage time occupied by HFOs was 0.02 in NSOZ and 0.42 in SOZ during the interictal period. During preictal period, they were 0.03 in NSOZ and 2 in SOZ. Conclusions: High-frequency oscillations are linked to SOZ in neocortical epilepsy. Our study demonstrates the prevalent occurrence of HFOs in SOZ. More and more burst of HFOs, especially FRs, means the onset of seizures.

In this paper, the observability analysis method based on meter placement was employed. Each consumer is classified, and the Distributed Generation (DG) is considered as a special negative load with constant power, which contains two types: photovoltaic (PV) power and wind turbine generation (WTG). The load variation is represented using typical load patterns. An efficient graph partitioning method is adopted to partition the weighted tree in the performing meter placement to achieve the network observability. Then an algorithm of optimization meter placement based on observability degree is presented to improve the state estimation accuracy. Finally, the validity of the proposed method has been tested in the IEEE 33-bus distribution network.

To achieve an accurate channel impulse response (CIR) during channel equalization and coherent detection, the channel estimation plays an important role to the performance of system, especially the receiver. In this paper, we investigated two main kinds of channel estimation methods for MB-OFDM based UWB system. The performances are compared using MATLAB simulation. The simulation shows the NBIDCE algorithm has better performance for WBAN-based healthcare systems.

The vibration of the fifth frame mill of 1450 Cold Tandem Rolling Mill in the rolling process was studied using finite element software ANSYS. The dynamic analysis of one-piece frame and two-piece frame on the fifth frame mill were carried on. The natural frequency and mode of vibration were calculated. Through analyzing, we obtained that two-piece frame performed better.

In this paper, iron ladle stress and deformation has been accurately calculated using finite element analysis software ANSYS based on 260t iron ladle in standing, lifting, tipping working conditions. Distribution of stress field was obtained. The stiffness and strength of the iron ladle has been evaluated. The results show that the iron ladle in the standing, lifting and tipping working conditions, structural deformation is small, the strength and stiffness meet the requirements. This research extends the working life of 260t iron ladle. It provides theoretical basis for producing and using of the iron ladle and further optimal designing.

Completed solid model of hydraulic mechanical power split CVT using Pro/E software basing on the transmission principle, achieved the whole transmission without interference assemble by the interference analysis and checking the gap. Carried on dynamics simulation analysis using ADAMS software, obtained the variation of plungers’ centroid and the bearing force in the rear end cover, it laid the theoretical foundation for subsequent experimental analysis.

In order to adapt to the needs of China's "Excellence Project", training the outstanding senior engineering talents to adapt to the era of development, we propose a new dynamic mode of course vertical integration. Using the method of organically connecting fundamental course and specialized course, the students' interests in learning will be improved. It will lay a solid foundation for students’ future work. Exploratory reform and practice on curriculum system, teaching contents, teaching method, teaching means, etc., we obtained effective methods and means. It will lay a solid foundation for the future teaching work.

Aiming at the vibration problems in Anshan Iron 5500mm heavy plate mill production line, the mill frame vibration in the main parts is researched by using the computer aided design method and the analytical method. Using SolidWorks 3D design software for frame modeling, the model is imported into the ANSYS finite element software, then 5500mm heavy plate mill stand 12 order natural frequencies and natural vibration type is calculated; applying analytical method of the 12th band of vertical vibration the natural frequency is calculated, and the finite element results is analysed comparatively. This paper lays the foundation for the study of the vibration of the mill stand in the future, provides a theoretical basis for the dynamic design of the mill stand.

In drainage and mining of the coal bed methane(CBM),pump valve jams caused by the settlement of pulverized coal particles directly affect the normal production of the coal bed methane(CBM).From the study of the pulverized coal particle size,this paper summarizes the law of the pulverized coal particle size change in various stages of the coal bed methane(CBM) production well drainage and ming.By analyzing the pulverized coal particle velocity distribution along the pump cylinder,the viewpoint that the pulverized coal particle has a higher axial velocity in the central part of the settlement and has a lower velocity near the wall surface is put forward to.Based on the theory,the motion track equation of the pulverized coal particle can be got by calculation.Under the condition of considering buoyancy,fluid resistance and pressure drag,instant drop speed of the pulverized coal in water is calculated.

Modeling the radio channel has historically been one of the most difficult parts of mobile radio system design. Channel modeling is the basis for the high-level network planning process (antennae heights, frequency assignment, base station subsystem parameter set, network architecture, etc... ). In this contribution, we will compare two of the most important outdoor macro-cell models, COST 231-WI model and ECC-33 model with simulation and measurement. The measurement is taken in urban areas.

According to the characteristics of the low efficiency of drainage equipment for coal bed methane wells, we analyzed and calculated the coefficient of fullness, plunger stroke loss, leakage and volume factor, which affect pump efficiency. After analyzing the displacement loss caused by various factors, we obtained coefficient of fullness of the most influential factor on the pump efficiency. By analyzing the change relationship among the coefficient of fullness and clearance space, gas fluid ratio, compression ratio and pumping speed, we found shrinking clearance space and reducing gas fluid ratio, compression ratio and pumping speed can increase coefficient of fullness, and we presented several improvement measures to improve pump efficiency. These measures will enable coal bed methane wells production more stable and efficient.

There are abundant coal bed methane resources in China, and recovery technology is considered a very important part in the development of coal bed methane. At present, coal bed methane production areas are still adopting the tubing liner pump, but because of the special working environment, in the pumping process, the fine breeze (sand) and other solid particles entering into the pump barrel is likely to cause the pump stuck, pipe string buried by sand and other issues. In view of the above problems, based on the ordinary tubing liner pump, through the increase of the anti-litter bypass style traveling valve housing and fixed valve housing, outside liner jacket, sand reservoir and liquid in tee joint measures we developed a new type of CBM special anti-clogging drainage pump and adopted finite element analysis software ANSYS to complete key parts of strength calculation. The use of this pump will effectively reduces the blocking of fine coal particles (sand) and other solid particles, decreases the pump's checking operation and workload of sand bailing, consequently improves efficiency, reduces overall operating costs.

In this paper a horizontal vibration problem in strip rolling was studied; dynamic model was established; the mechanism of self-excited vibration was analyzed. The main reason of surface quality of strip is self-excited vibration. A vertical natural frequency and vibration mode of the rolling mill are obtained by finite element method. It lays the theoretic foundation for future researches on rolling mill vibraton.

According to the vibration happened in rolling process of 1780 tandem rolling mill. Finite element method and structural dynamic method were used to analysis in this paper. The natural frequencies of the rack were calculated. The comparision between two methods were done. It was helpful for designing and reducing vibration of the rolling process.

Through to the petroleum drilling machine serial design pattern malpractice's analysis, this article proposed petroleum drilling machine's concurrent design uses in the petroleum drilling machine enterprise based on PDM the platform. Elaborated the concurrent design in the petroleum drilling machine production process's application, analyzed PDM and the concurrent design relational model as well as PDM and the petroleum drilling machine's concurrent design key technologies.

Objectives To investigate influences of the functional polymorphisms of Cytochrome P450 isozymes 2A6 (CYP2A6), 2B6 (CYP2B6), and 2C9 (CYP2C9) on pharmacokinetics of VPA in vivo. Patients and methods In the study, we analyzed the genotypes of CYP2A6, CYP2B6, and CYP2C9 and their contribution to the steady-state standardized plasma VPA concentrations in 179 subjects with epilepsy of a Northern Han Chinese population. The genotypes were detected by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results The subjects with one or two variant CYP2A6*4 alleles showed higher mean plasma VPA concentrations compared with non-*4 alleles [(3.4 ± 0.4) μg kg ml−1 mg−1 vs. (3.6 ± 0.4) μg kg ml−1 mg−1, p = 0.0055]. A significant difference [one-way ANOVA (p = 0.0203)] was also found between mean plasma VPA concentrations and the CYP2B6 genotypes. In addition, subjects with the heterozygous genotype CYP2C9*3 had higher mean plasma VPA concentrations than did those subjects with the wild-type genotype [(3.9 ± 0.4) μg kg ml−1 mg−1 vs. (3.4 ± 0.4) μg kg ml−1 mg−1, p = 0.0001]. Conclusion The presently evaluated variant alleles in the CYP2A6, CYP2B6, and CYP2C9 genes may explain part of the substantial variability in VPA pharmacokinetics between different subjects.

BACKGROUND: Epidemiological evidence of co-use of alcohol and areca nuts suggests a potential central interaction between arecoline, a major alkaloid of areca and a muscarinic receptor agonist, and ethanol. Moreover, the central cholinergic system plays an important role in the depressant action of ethanol and barbiturates. The purpose of this study was to investigate the effects of arecoline on pentobarbital- and ethanol-induced hypnosis in mice. METHODS: Male ICR mice were tested for locomotor activity following acute systemic administration of ethanol alone, arecoline alone, or ethanol plus arecoline. For the loss of the righting reflex (LORR) induced by pentobarbital and ethanol, sleep latency and sleeping duration were evaluated in mice treated with arecoline alone or the combination of arecoline and scopolamine or methscopolamine. RESULTS: Ethanol (1.0 to 3.0 g/kg, i.p.) reduced locomotor activity significantly and a declining trend was observed after treatment with arecoline (0.25 to 1.0 mg/kg, i.p.), but there were no synergistic effects of ethanol and arecoline on locomotor activity. The experiments on LORR demonstrated that arecoline (0.125 to 1.0 mg/kg, s.c.) shortened the duration of sleeping induced by ethanol (4.0 g/kg, i.p.), but not pentobarbital (45 mg/kg, i.p.). In addition, alterations of sleep latency were not obvious in both pentobarbital- and ethanol-induced LORR. Statistical analyses revealed that scopolamine (centrally acting), but not methscopolamine (peripherally acting), could antagonize the effect of arecoline on the duration of ethanol-induced LORR in mice. CONCLUSIONS: These results suggest that central muscarinic receptor is a pharmacological target for the action of arecoline to modulate ethanol-induced hypnosis.

Nonfunctional parathyroid carcinoma (PTC) is one of the rarest malignant diseases and only nine cases have been reported during the last 23 years. We present a case of nonfunctioning PTC and review the literature in an effort to provide a better understanding of this rare disorder. One patient with nonfunctioning PTC was presented, detailing the clinical features, histologic findings, diagnosis, and treatment. Together with data from the other nine cases reported last 23 years, the related literature is also reviewed. The presented case was a 47-year-old man with a 2-month history of an enlarging painless cervical mass followed by a 2-week history of hoarseness. Clinical and laboratory evaluations failed to reveal evidence of hyperparathyroidism. Pathological analysis of the resected tumor disclosed findings consistent with PTC. The nonsecretory state of the tumor was further supported by immunoreactivity for parathyroid hormone in tissue, and normal serum levels of this peptide and calcium preoperatively and postoperatively. Most nonfunctional PTC is detected late due to a paucity of symptoms, of which a palpable neck mass is the most common. Patients with nonfunctioning PTC appear to have a poorer prognosis than do those with functioning parathyroid cancers.

The policy of synchronous vacations of partial servers is considered in an multi-server queuing system with balking and reneging. Some fixed partial idle servers take synchronous multiple vacations when these servers become idle at an instant that a customer leaves the system. In this article, by considering the two cases that the partial servers are on vacation and not on vacation, the distributions of the conditional waiting time for customers who join the system when all the available servers are busy and eventually acquire service are obtained. Based on these, the distribution of the conditional waiting time of customers given that they join the system when all available servers are busy and eventually acquire service is derived.

Background Plasminogen activator inhibitor-1 (PAI-1) is reported to be expressed in many cancer cell types and regarded as one of the most informative biochemical markers for poor prognosis. However, no previous study has evaluated whether PAI-1 could serve as a target in antitumor and antimetastasis therapies of colorectal cancer (CRC). Methods The plasma level of PAI-1 in CRC patients was detected and its correlation with the clinicopathologic features was evaluated. PAI-1 protein expression was assessed by Western blot assay and immunohistochemistry. The biologic consequences of PAI-1 silencing in colon cancer cell lines and CRC bearing nude mice were also investigated. Results Plasma PAI-1 level was higher in CRC patients with liver metastasis and correlated with liver metastasis, tumor size, differentiation, serosa infiltration, Duke’s stage, and lymphatic metastasis. PAI-1 protein expression in the CRC tissue of patients with liver metastasis was significantly greater than that in those without liver metastasis. In addition, the abilities of proliferation, invasion, and migration of CRC cells transfected with lentivirus expressing PAI-1 small interfering RNA were reduced significantly. Nude mice inoculated with PAI-1 knockdown cells also had fewer metastatic nodules in the liver and smaller tumor volumes. Conclusion Plasma PAI-1 level was increased in CRC patients with liver metastasis, and PAI-1 silencing may significantly compromise the malignant behaviors of CRC cells in vitro and in vivo. These findings may provide evidence for PAI-1 targeted therapy of CRC.

Finite element method and structural mechanics method are used to study the blast furnace shell modal analysis and the natural frequencies and mode shapes have been calculated. The two methods were compared and validated , and the results provide a theoretical foundation for the anti-vibration capabilities design of blast furnace shell in the future .

Objective To investigate the effects of and mechanisms underlying the activation of the p75 tumor necrosis factor receptor (p75TNFR) signaling pathway in inflammatory responses in mice with traumatic brain injury. Methods We first generated hybridomas that produced antibodies specific for p75TNFR, by inoculating BALB/c mice with antigenic peptides derived from mouse p75TNFR, which is critical to the binding of tumor necrosis factor-alpha (TNF-α) and p75TNFR. The isotype, epitope, titer, specificity, and affinity constant of monoclonal antibodies (mAbs) were determined using commercial kits and enzyme-linked immunosorbent assay. We then screened the agonist antibody via L929 cytotoxicity assay. The levels of inflammatory factors were detected in C57BL/6 mice with traumatic brain injury and then the mice were injected with either saline (control) or p75TNFR agonist mAb. Furthermore, we investigated the effects of p75TNFR agonist mAb on p38MAPK and nuclear factor-κB signals. Results Seven mAbs against p75TNFR were generated. Among them, the mAb D8F2 could markedly enhance the cytotoxicity of TNF-α on L929 cells. In a traumatic brain injury model, D8F2 could inhibit the levels of inflammatory factors and downregulate RNA transcription of these factors by suppressing the activation of p38 mitogen-activated protein kinase and nuclear factor-κB. Conclusion The mAb D8F2 could inhibit posttraumatic inflammatory responses effectively. In this study, we developed an agonist anti-mouse p75TNFR mAb, which may be used in the future to devise new strategies for the clinical treatment of inflammation after trauma.

The pelvic autonomic nerves innervate the pelvic viscera, and carry a high risk of damage during surgery. This high risk has been ascribed to the complex interrelationship of pelvic paravisceral structures and the difficulty in identifying particular structures, despite the fact that the anatomic characteristics of the pelvic autonomic plexus have been well documented. We dissected ten male embalmed adult cadavers with particular attention to the quantitative parameters of the pelvic plexus and its subsidiary plexus. The right inferior hypogastric plexus and its rectal branch were found to be significantly longer and wider than the left one, while the transverse diameter of the vesical and prostatic branches of the left side was significantly larger the right. The inferior mesenteric plexus gave off fibers directly to form the pelvic plexus in four of 20 hemipelves (20%). In the side-by-side comparison, the distance to midpoint of the sacral promontory of the left rectal plexus was significantly longer than that of the right, whereas the maximum length (the length of the longest nerve fiber from origin to corresponding organ) of the left vesical plexus was significantly shorter than that of the right. Additionally, the craniocaudal and dorsoventral diameters of the right pelvic autonomic plexus were significantly shorter those of the left. The quantitative parameters relating to the pelvic autonomic plexuses not only can enhance our understanding of its anatomy and function, but can also be used as references for surgical procedures and robot-assisted surgery.

Background Hydrogen has been considered as a novel antioxidant that prevents injuries resulted from ischemia-reperfusion (I/R) injury in various tissues. The study was designed to determine the effect of hydrogen-rich saline on the smooth muscle contractile response to KCl, and on epithelial proliferation and apoptosis of intestine subjected to I/R. Methods Intestinal I/R injury was induced in Sprague-Dawley rats using bulldog clamps in superior mesenteric artery by 45 min ischemia followed by 1 h reperfusion. Rats were divided randomly into four groups: sham-operated, I/R, I/R plus saline treatment, and I/R plus hydrogen-rich saline treatment groups. Hydrogen-rich saline (>0.6 mM, 6 mL/kg) or saline (6 mL/kg) was administered, respectively, via tail vein 30 min prior to reperfusion. Following reperfusion, segments of terminal jejunum were rapidly taken and transferred into isolated organ bath and responses to KCl were recorded. Samples of terminal jejunum were also taken for measuring malondialdehyde and myeloperoxidase. Apoptosis in intestinal epithelium was determined with terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling technique (TUNEL). Expression and distribution of proliferating cell nuclear antigen (PCNA) were detected with immunohistochemistry. Results Hydrogen-rich saline treatment significantly attenuated the severity of intestinal I/R injury, with inhibiting of I/R-induced apoptosis, and promoting enterocytes proliferation. Moreover, Hydrogen-rich saline treatment significantly limited the neutrophil infiltration, lipid oxidation, and ameliorated the decreased contractility response to KCl in the intestine subjected to I/R. Conclusions These results suggest that hydrogen treatment has a protective effect against intestinal contractile dysfunction and damage induced by intestinal I/R. This protective effect is possibly due to its ability to inhibit I/R-induced oxidative stress, apoptosis, and to promote epithelial cell proliferation.

Organ dysfunction or multiple organ dysfunction syndrome caused by developing immunological dysfunction and subsequent sepsis or the systemic inflammatory response syndrome after trauma is the leading cause of death in trauma patient. It is believed that mitogen-activated protein kinase) (p38MAPK) is one of the most important kinases in inflammatory signaling. In this study, the change of p38 MAPK signaling pathway in trauma patient with different severity and its clinical significance in trauma inflammation were investigated.One hundred fifty major trauma patients were included in the study and divided into three groups according to injury severity score (ISS). All data required to calculate ISS and determine organ function were registered on admission and during the ICU-stay. Peripheral blood samples were collected from trauma patients 6 h, 1 d, 3 d, 5 d, and 7 d after injury. RQ-PCR and Western blot was used to examine the changes in gene expression, protein expression, and activation level of leukocyte p38 MAPK. Plasma IL-6 and TNFalpha were assayed by ELISA.Organ dysfunction in 33 trauma patients developed and eight deaths occurred after 24 h in ICU. The causes of death included severe ARDS, MODS, and irreversible brain injury. Incidence of organ dysfunction was related to the increase of injury severity (P0.01). Compared with healthy control, the gene expression of p38 MAPK in trauma patients increased significantly 6 h after injury (P0.05), and reached a maximum in 1 d (P0.01). The expression maintained a high level for 7 d (P0.05). One day after injury, significant elevation was observed in protein expression and activation level of p38 MAPK (P0.05), as well as the plasma TNFalpha and IL-6 level (P0.01). Further investigation found that the gene expression, protein expression, and activation levels of p38 MAPK increased with higher ISS (P0.05), and the elevation of plasma TNFalpha and IL-6 level was associated with the increase of activated p38 MAPK and ISS (P0.05).p38 MAPK signal pathway was activated in trauma patients. The severity of trauma had highly positive correlation with the expression and activation of p38 MAPK, as well as the elevation of plasma TNFalpha and IL-6 expression. These findings indicate that p38 MAPK signaling pathway plays an important role in the pathological mechanism of trauma.

BACKGROUND: Childhood sexual abuse (CSA) seriously influences children's psychological status. This study aimed to investigate the relationship between CSA and the psychiatric disorders. METHODS: An anonymous and retrospective questionnaire survey was carried out in 1307 college students (aged 18-25 years; 701 females, 606 males) to investigate the participants' CSA experience by means of a complete random sampling method. The Symptom Check-List-90 (SCL-90) test was used to study the victims' psychiatric aspects. RESULTS: 22.11% (155/701) of the female students and 14.69% (89/606) of the male students experienced physical and/or non-physical contact CSA before age 18, with a significant difference between female and male (P

An undulation pump is a special rotary blood pump in which rotation of a brushless DC motor is transformed to an undulating motion by a disc in the pump housing attached by means of a special link mechanism. In the blood pump, a closed line between the disc and housing moves from the inlet to the outlet by this undulating disc motion, which sucks and pushes the blood from the inlet to the outlet. Because the same phenomena occurs at both sides of the disc, a continuous flow is obtained when the motor rotational speed is constant. The pump flow pattern can be easily changed from continuous flow to pulsatile flow by controlling the motor drive current pattern. A seal membrane made of segmented polyurethane protects the blood from invading the link mechanism as well as the motor. UPTAH is fabricated with two undulation pumps and two brushless DC motors. Its size is 75 mm in diameter and 80 mm long, and it has one of the great advantage of no compliance chamber required in the system. UPTAHs were implanted under cardiopulmonary bypass (CPB) into the chest cavities of 16 goats, each weighing between 41 and 72 kg. No anticoagulant and antiplatelet agent was used after the surgery. The left atrial pressure was automatically controlled to prevent its elevation and sucking of the atrial wall into the atrial cuff. The following results were obtained: (1) UPTAHs fit well into all the goats; (2) the longest survival was 19.8 days, the cause of death was bleeding from the aortic anastomosis; (3) No thrombus was observed in the blood pump despite no anticoagulant use. Hemolysis depended upon the length of CPB during surgery. When CPB time was within 2 hours, hemolysis level returned to baseline within a few days of the surgery. UPTAH is a promising implantable TAH, because of its small size and easy controllability.

AIM: To investigate the levels of D-dimer (DD) and von Willebrand factor (vWF) and the relationship between DD and vWF in ulcerative colitis (UC) patients. METHODS: A total of 29 plasma specimens were obtained from patients with ulcerative colitis (male 13, female 16), aged 21-47 years (33 ± 11). Disease activity was assessed by Truelove-Writeria. Patients with a score of above 5 were regarded as having active colitis. Twenty healthy people (male 12, female 8), aged 19-53 years (31 ± 14), served as normal controls. Blood samples were taken from an antecubital vein puncture. Blood (1.8 mL) was injected into the tubes containing sodium citrate (0.13 mmol/L). The plasma was obtained by centrifugation at 3000 r·min-1 for 10 min, and stored at -80 °C until assayed by ELISA. RESULTS: The mean plasma levels of DD and vWF in active UC patients were significantly higher than those of the controls (0.69 ± 0.41 vs 0.27 ± 0.11, P < 0.01; 143 ± 46 vs 103 ± 35, P < 0.01). The mean plasma levels of DD in the patients with active disease were higher than those with inactive disease (0.69 ± 0.41 vs 0.48 ± 0.29, P < 0.05). The levels of vWF were not different between active and inactive patients. DD levels were positively related to vWF levels (r = 0.574, P < 0.01). There was no significant difference between levels of DD and vWF and the scope of disease and sex of the patients. CONCLUSION: vWF is an important feature and a good marker of UC; intravascular thrombus and endothelial cell dysfunction were found in UC patients; and the combined test of DD and vWF is helpful to distinguish the activity of the UC patients.