ObjectiveBased on the concept of quality by design（QbD）， the processing process of calcined Pyritum was optimized， and its X-ray diffraction（XRD） fingerprint was established. MethodsThe safety， effectiveness and quality controllability of calcined Pyritum were taken as the quality profile（QTPP）， the color， hardness， metallic luster， phase composition， the contents of heavy metals and hazardous elements were taken as the critical quality attributes（CQAs）， and the calcination temperature， calcination time， paving thickness and particle size were determined as the critical process parameters（CPPs）. Differential thermal analysis， X-ray diffraction（XRD） and inductively coupled plasma mass spectrometry（ICP-MS） were used to analyze the correlation between the calcination temperature and CQAs of calcined Pyritum. Then， based on the criteria importance through intercriteria correlation（CRITIC）-entropy weight method， the optimal processing process of calcined Pyritum was optimized by orthogonal test. Powder XRD was used to analyze the phase of calcined Pyritum samples processed according to the best process， and the mean and median maps of calcined Pyritum were established by the superposition of geometric topological figures， and similarity evaluation and cluster analysis were carried out. ResultsThe results of single factor experiments showed that the physical phase of Pyritum changed from FeS₂ to Fe₇S₈ during the process of temperature increase， the color gradually deepened from dark yellow， and the contents of heavy metals and harmful elements decreased. The optimized processing process of calcined Pyritum was as follows：calcination temperature at 750 ℃， calcination time of 2.5 h， paving thickness of 3 cm， particle size of 0.8-1.2 cm， vinegar quenching 1 time［Pyritum-vinegar（10∶3）］. After calcination， the internal structure of Pyritum was honeycomb-shaped， which was conducive to the dissolution of active ingredients. XRD fingerprints of 13 batches of calcined Pyritum characterized by 10 common peaks were established. The similarities of the relative peak intensities of the XRD fingerprints of the analyzed samples were>0.96， and it could effectively distinguish the raw products and unqualified products. ConclusionTemperature is the main factor affecting the quality of calcined Pyritum. After processing， the dissolution of the effective components in Pyritum increases， and the contents of heavy metals and harmful substances decrease， reflecting the function of processing to increase efficiency and reduce toxicity. The optimized processing process is stable and feasible， and the established XRD fingerprint can be used as one of the quality control standards of calcined Pyritum.

ObjectiveBased on the concept of quality by design（QbD）， the processing process of calcined Pyritum was optimized， and its X-ray diffraction（XRD） fingerprint was established. MethodsThe safety， effectiveness and quality controllability of calcined Pyritum were taken as the quality profile（QTPP）， the color， hardness， metallic luster， phase composition， the contents of heavy metals and hazardous elements were taken as the critical quality attributes（CQAs）， and the calcination temperature， calcination time， paving thickness and particle size were determined as the critical process parameters（CPPs）. Differential thermal analysis， X-ray diffraction（XRD） and inductively coupled plasma mass spectrometry（ICP-MS） were used to analyze the correlation between the calcination temperature and CQAs of calcined Pyritum. Then， based on the criteria importance through intercriteria correlation（CRITIC）-entropy weight method， the optimal processing process of calcined Pyritum was optimized by orthogonal test. Powder XRD was used to analyze the phase of calcined Pyritum samples processed according to the best process， and the mean and median maps of calcined Pyritum were established by the superposition of geometric topological figures， and similarity evaluation and cluster analysis were carried out. ResultsThe results of single factor experiments showed that the physical phase of Pyritum changed from FeS₂ to Fe₇S₈ during the process of temperature increase， the color gradually deepened from dark yellow， and the contents of heavy metals and harmful elements decreased. The optimized processing process of calcined Pyritum was as follows：calcination temperature at 750 ℃， calcination time of 2.5 h， paving thickness of 3 cm， particle size of 0.8-1.2 cm， vinegar quenching 1 time［Pyritum-vinegar（10∶3）］. After calcination， the internal structure of Pyritum was honeycomb-shaped， which was conducive to the dissolution of active ingredients. XRD fingerprints of 13 batches of calcined Pyritum characterized by 10 common peaks were established. The similarities of the relative peak intensities of the XRD fingerprints of the analyzed samples were>0.96， and it could effectively distinguish the raw products and unqualified products. ConclusionTemperature is the main factor affecting the quality of calcined Pyritum. After processing， the dissolution of the effective components in Pyritum increases， and the contents of heavy metals and harmful substances decrease， reflecting the function of processing to increase efficiency and reduce toxicity. The optimized processing process is stable and feasible， and the established XRD fingerprint can be used as one of the quality control standards of calcined Pyritum.

Amyloidosis is a rare disease.This paper reports a case of localized secondary hypopharyngeal amyloidosis presenting with pulmonary tuberculosis as the initial symptom.The patient lacked specific clinical manifestations and primarily exhibited symptoms such as cough,sputum production,acid reflux,belching,and abdominal pain.Chest CT indicated bronchiectasis with infection and pulmonary tuberculosis.Digestive endoscopy revealed a white mucosal elevation at the right pyriform sinus of the hypopharynx.Pathological diagnosis confirmed amyloid deposits in the hypopharyngeal mucosal tissue.The patient tested positive for anti-amyloid A antibodies,Congo red staining(+),and periodate Schiff staining(+).Amyloidosis commonly affects the digestive system and may have various etiologies,often presenting with symptoms that overlap with other digestive system diseases,leading to frequent misdiagnosis and missed optimal treatment opportunities.The hypopharynx,a highly folded and narrow chamber that serves as a common passage for the digestive and respiratory tracts,can be effectively evaluated for amyloidosis using digestive endoscopy.

ObjectiveTo investigate the regulatory effects of Xuanfu Daizhetang on a mouse model of allergic asthma induced by ovalbumin （OVA）. MethodSixty female BALB/c mice （6-8 weeks old， SPF） were randomly divided into groups. Ten mice were assigned to the normal group and given 0.2 mL of saline， while the remaining groups received intraperitoneal injections of Al（OH）₃ at 5 g·L^-1 and OVA at 1 g·L^-1. The mice were divided into normal group （10 mL·kg^-1 saline）， OVA model group （10 mL·kg^-1 saline）， dexamethasone group （OVA+DEX， 1 mg·kg^-1）， OVA+ low-dose Xuanfu Daizhetang group （OVA+XL， 7.065 g·kg^-1）， OVA+ medium-dose Xuanfu Daizhetang group （OVA+XM， 14.13 g·kg^-1）， and OVA+ high-dose Xuanfu Daizhetang group （OVA+XH， 28.26 g·kg^-1）. An OVA-induced asthma model was established in mice. Hematoxylin-eosin （HE） and periodic acid-Schiff （PAS） staining methods were used to observe bronchial tissue pathological changes. Enzyme-linked immunosorbent assay （ELISA） was performed to measure the levels of immunoglobulin E （IgE）， interleukin-4 （IL-4）， IL-5， IL-13， IL-17A， and γ interferon （IFN-γ） in bronchoalveolar lavage fluid. Western blot was used to detect the phosphorylation of extracellular signal-regulated kinase （ERK）， p38 mitogen-activated protein kinase （MAPK）， and c-Jun N-terminal kinase （JNK） proteins in lung tissue. ResultCompared with the normal group， the OVA model group showed increased inflammatory cell infiltration in mouse alveoli， elevated levels of IL-4， IL-5， IL-13， IL-17A， IFN-γ in bronchoalveolar lavage fluid， and IgE in serum （P<0.05， P<0.01）， and promoted phosphorylation of MAPK signaling pathway-related proteins. Compared with the model group， the OVA+XL， OVA+XM， and OVA+XH groups showed reduced inflammatory cell infiltration in mouse alveoli， decreased levels of IL-4， IL-5， IL-13， IL-17A， IFN-γ in bronchoalveolar lavage fluid， and IgE in serum （P<0.05， P<0.01）， and inhibited phosphorylation of MAPK signaling pathway-related proteins. ConclusionThe results of this study suggest that Xuanfu Daizhetang has potential anti-allergic asthma activity， providing a theoretical basis for its future clinical application.

Objective:We investigated the incidence of surgical site infection (SSI) following emergency abdominal surgery (EAS) in China and further explored its risk factors, providing a reference for preventing and controlling SSI after EAS.Methods:This was an observational study. Data of patients who had undergone EAS and been enrolled in the Chinese SSI Surveillance Program during 2018–2021were retrospectively analyzed. All included patients had been followed up for 30 days after surgery. The analyzed data consisted of relevant patient characteristics and perioperative clinical data, including preoperative hemoglobin, albumin, and blood glucose concentrations, American Society of Anesthesiologists (ASA) score, grade of surgical incision, intestinal preparation, skin preparation, location of surgical site, approach, and duration. The primary outcome was the incidence of SSI occurring within 30 days following EAS. SSI was defined as both superficial and deep incisional infections and organ/space infections, diagnoses being supported by results of microbiological culture of secretions and pus. Secondary outcomes included 30-day postoperative mortality rates, length of stay in the intensive care unit (ICU), duration of postoperative hospitalization, and associated costs. The patients were classified into two groups, SSI and non-SSI, based on whether an infection had been diagnosed. Univariate and multivariate logistic regression analyses were performed to identify risk factors associated with SSI following EAS.Results:The study cohort comprised 5491 patients who had undergone EAS, comprising 3169 male and 2322 female patients. SSIs were diagnosed in 168 (3.1%) patients after EAS (SSI group); thus, the non-SSI group consisted of 5323 patients. The SSIs comprised superficial incision infections in 69 (41.1%), deep incision infections in 51 (30.4%), and organ or space infections in 48 (28.6%). Cultures of secretions and pus were positive in 115 (68.5%) cases. The most frequently detected organism was Escherichia coli (47/115; 40.9%). There were no significant differences in sex or body mass index between the SSI and non-SSI groups (both P>0.05). However, the proportion of individuals aged 60 years or older was significantly greater in the SSI than in the non-SSI group (49.4% [83/168] vs. 27.5% [1464/5323), χ 2=38.604, P<0.001). Compared with the non-SSI group, the SSI group had greater proportions of patients with diabetes (11.9% [20/168] vs. 4.8% [258/5323], χ 2=16.878, P<0.001), hypertension (25.6% [43/168] vs. 12.2% [649/5323], χ 2=26.562, P<0.001); hemoglobin <110 g/L (27.4% [46/168] vs. 13.1% [697/5323], χ 2=28.411, P<0.001), and albuminemia <30 g/L (24.4% [41/168] vs. 5.9% [316/5323], χ 2=91.352, P<0.001), and a reduced rate of preoperative skin preparation (66.7% [112/168] vs. 75.9% [4039/5323], χ 2=7.491, P=0.006). Furthermore, fewer patients in the SSI group had preoperative ASA scores of between one and two (56.0% [94/168] vs. 88.7% [4724/5323], χ 2=162.869, P<0.001) in the non-SSI group. The incidences of contaminated and infected incisions were greater in the SSI group (63.1% [106/168] vs. 38.6% [2056/5323], χ 2=40.854, P<0.001). There was a significant difference in surgical site distribution between the SSI and non-SSI groups (small intestine 29.8% [50/168] vs. 10.6% [565/5323], colorectal 26.2% [44/168] vs. 5.6% [298/5 323], and appendix 24.4% [41/168] vs. 65.1% [3465/5323]) χ 2=167.897, P<0.001), respectively. There was a significantly lower proportion of laparoscope or robotic surgery in the non-SSI group (24.4 % [41/168] vs. 74.2% [3949/5323], χ 2=203.199, P<0.001); the percentage of operations of duration less than 2 hours was significantly lower in the SSI than non-SSI group (35.7% [60/168] vs. 77.4% [4119/5323], χ 2=155.487, P<0.001). As to clinical outcomes, there was a higher 30-day postoperative mortality rate (3.0%[5/168] vs. 0.2%[10/5323], χ 2=36.807, P<0.001) and higher postoperative ICU occupancy rate (41.7% [70/168] vs. 19.7% [1046/5323], χ 2=48.748, P<0.001) in the SSI group. The median length of stay in the ICU (0[2] vs. 0[0] days, U=328597.000, P<0.001), median total length of stay after surgery (16[13] vs. 6[5] days, U=128146.000, P<0.001), and median hospitalization cost (ten thousand yuan, 4.7[4.4] vs. 1.7[1.8], U=175965.000, P<0.001) were all significantly greater in the SSI group. Multivariate logistic regression analysis revealed that the absence of skin preparation before surgery (OR=2.435,95%CI: 1.690–3.508, P<0.001), preoperative albuminemia <30 g/L (OR=1.680, 95%CI: 1.081–2.610, P=0.021), contaminated or infected incisions (OR=3.031, 95%CI: 2.151–4.271, P<0.001), and laparotomy (OR=3.436, 95% CI: 2.123–5.564, P<0.001) were independent risk factors of SSI. Operative duration less than 2 hours (OR=0.465, 95%CI: 0.312–0.695, P<0.001) and ASA score of 1–2 (OR=0.416, 95% CI: 0.289–0.601, P<0.001) were identified as independent protective factors for SSI. Conclusions:It is important to consider the nutritional status in the perioperative period of patients undergoing EAS. Preoperative skin preparation should be conducted and, whenever possible, laparoscope or robot-assisted surgery. Duration of surgery should be as short as possible while maintaining surgery quality and improving patient care.

Objective:We investigated the incidence of surgical site infection (SSI) following emergency abdominal surgery (EAS) in China and further explored its risk factors, providing a reference for preventing and controlling SSI after EAS.Methods:This was an observational study. Data of patients who had undergone EAS and been enrolled in the Chinese SSI Surveillance Program during 2018–2021were retrospectively analyzed. All included patients had been followed up for 30 days after surgery. The analyzed data consisted of relevant patient characteristics and perioperative clinical data, including preoperative hemoglobin, albumin, and blood glucose concentrations, American Society of Anesthesiologists (ASA) score, grade of surgical incision, intestinal preparation, skin preparation, location of surgical site, approach, and duration. The primary outcome was the incidence of SSI occurring within 30 days following EAS. SSI was defined as both superficial and deep incisional infections and organ/space infections, diagnoses being supported by results of microbiological culture of secretions and pus. Secondary outcomes included 30-day postoperative mortality rates, length of stay in the intensive care unit (ICU), duration of postoperative hospitalization, and associated costs. The patients were classified into two groups, SSI and non-SSI, based on whether an infection had been diagnosed. Univariate and multivariate logistic regression analyses were performed to identify risk factors associated with SSI following EAS.Results:The study cohort comprised 5491 patients who had undergone EAS, comprising 3169 male and 2322 female patients. SSIs were diagnosed in 168 (3.1%) patients after EAS (SSI group); thus, the non-SSI group consisted of 5323 patients. The SSIs comprised superficial incision infections in 69 (41.1%), deep incision infections in 51 (30.4%), and organ or space infections in 48 (28.6%). Cultures of secretions and pus were positive in 115 (68.5%) cases. The most frequently detected organism was Escherichia coli (47/115; 40.9%). There were no significant differences in sex or body mass index between the SSI and non-SSI groups (both P>0.05). However, the proportion of individuals aged 60 years or older was significantly greater in the SSI than in the non-SSI group (49.4% [83/168] vs. 27.5% [1464/5323), χ 2=38.604, P<0.001). Compared with the non-SSI group, the SSI group had greater proportions of patients with diabetes (11.9% [20/168] vs. 4.8% [258/5323], χ 2=16.878, P<0.001), hypertension (25.6% [43/168] vs. 12.2% [649/5323], χ 2=26.562, P<0.001); hemoglobin <110 g/L (27.4% [46/168] vs. 13.1% [697/5323], χ 2=28.411, P<0.001), and albuminemia <30 g/L (24.4% [41/168] vs. 5.9% [316/5323], χ 2=91.352, P<0.001), and a reduced rate of preoperative skin preparation (66.7% [112/168] vs. 75.9% [4039/5323], χ 2=7.491, P=0.006). Furthermore, fewer patients in the SSI group had preoperative ASA scores of between one and two (56.0% [94/168] vs. 88.7% [4724/5323], χ 2=162.869, P<0.001) in the non-SSI group. The incidences of contaminated and infected incisions were greater in the SSI group (63.1% [106/168] vs. 38.6% [2056/5323], χ 2=40.854, P<0.001). There was a significant difference in surgical site distribution between the SSI and non-SSI groups (small intestine 29.8% [50/168] vs. 10.6% [565/5323], colorectal 26.2% [44/168] vs. 5.6% [298/5 323], and appendix 24.4% [41/168] vs. 65.1% [3465/5323]) χ 2=167.897, P<0.001), respectively. There was a significantly lower proportion of laparoscope or robotic surgery in the non-SSI group (24.4 % [41/168] vs. 74.2% [3949/5323], χ 2=203.199, P<0.001); the percentage of operations of duration less than 2 hours was significantly lower in the SSI than non-SSI group (35.7% [60/168] vs. 77.4% [4119/5323], χ 2=155.487, P<0.001). As to clinical outcomes, there was a higher 30-day postoperative mortality rate (3.0%[5/168] vs. 0.2%[10/5323], χ 2=36.807, P<0.001) and higher postoperative ICU occupancy rate (41.7% [70/168] vs. 19.7% [1046/5323], χ 2=48.748, P<0.001) in the SSI group. The median length of stay in the ICU (0[2] vs. 0[0] days, U=328597.000, P<0.001), median total length of stay after surgery (16[13] vs. 6[5] days, U=128146.000, P<0.001), and median hospitalization cost (ten thousand yuan, 4.7[4.4] vs. 1.7[1.8], U=175965.000, P<0.001) were all significantly greater in the SSI group. Multivariate logistic regression analysis revealed that the absence of skin preparation before surgery (OR=2.435,95%CI: 1.690–3.508, P<0.001), preoperative albuminemia <30 g/L (OR=1.680, 95%CI: 1.081–2.610, P=0.021), contaminated or infected incisions (OR=3.031, 95%CI: 2.151–4.271, P<0.001), and laparotomy (OR=3.436, 95% CI: 2.123–5.564, P<0.001) were independent risk factors of SSI. Operative duration less than 2 hours (OR=0.465, 95%CI: 0.312–0.695, P<0.001) and ASA score of 1–2 (OR=0.416, 95% CI: 0.289–0.601, P<0.001) were identified as independent protective factors for SSI. Conclusions:It is important to consider the nutritional status in the perioperative period of patients undergoing EAS. Preoperative skin preparation should be conducted and, whenever possible, laparoscope or robot-assisted surgery. Duration of surgery should be as short as possible while maintaining surgery quality and improving patient care.

Objective:To assess the value of acoustic radiation force impulse (ARFI) elastography in the diagnosis of children with biliary atresia.Methods:A prospective survey of infants with hepatitis syndrome and hyperbi-lirubinemia in Xinhua Hospital Affiliated to Shanghai Jiaotong University School of Medicine from January 2017 to December 2018 was performed.The children with hepatitis syndrome were divided into the biliary atresia group( n=45) and non- biliary atresia group( n=30). Thirty children with hyperbilirubinemia were selected as the control group.Shear wave speed (SWS) of all infants was collected by ARFI ultrasound and compared among 3 groups.Receiver ope-rating characteristic curve(ROC curve) was used to analyze the optimal threshold value for SWS in the diagnosis of biliary atresia. Results:The mean SWS values in the biliary atresia group, non-biliary atresia group and the control group were (1.79±0.29) m/s, (1.26±0.12) m/s and (1.08±0.06) m/s, respectively.Compared with the control group, the mean SWS values in the biliary atresia group and non-biliary atresia group were significantly higher ( t=165.43, 15.75, all P<0.05). The mean SWS value in the non-biliary atresia group was significantly lower than that in the biliary atresia group ( t=90.27, P<0.05). With the non-biliary atresia group as reference, the area under the ROC curve of SWS for diagnosis of biliary atresia was 0.98(95% CI: 0.95-1.00), the optimal threshold was 1.45 m/s, and the sensitivity and specificity were 88.9% and 96.7%, respectively. Conclusions:Rapid non-invasive ARFI elastography is effective in the diagnosis of biliary atresia, and thus has important value for early diagnosis and treatment in clinical practice.

Objective To investigate the prevalence of iron deficiency(ID)and iron deficiency anemia (IDA) in pregnant women in urban areas of China. Methods The study was a national cross-sectional survey conducted from September 19th, 2016 to November 20th, 2016. According to the classification of the National Bureau of Statistics, all survey sites were set up in 6 regions of the country. Pregnant women were continuously selected using multistage stratified sampling. A total of 12 403 pregnant women were collected and examined for serum ferritin and hemoglobin levels. Results The median serum ferritin level during pregnancy was 20.60 μg/L(11.78-36.98 μg/L), the hemoglobin level was(118±12)g/L. With the progress of pregnancy, the levels of serum ferritin and hemoglobin decreased gradually. The median serum ferritin levels in the first, second trimester and third trimester were 54.30 μg/L(34.48-94.01 μg/L), 28.60 μg/L(16.40-50.52 μg/L), and 16.70 μg/L(10.20-27.00 μg/L)respectively(P<0.01). The mean hemoglobin levels were(127 ± 10)g/L,(119 ± 11)g/L and(117 ± 11)g/L respectively(P<0.01). The prevalence of ID in urban pregnant women was 48.16%(5 973/12 403), and IDA prevalence was 13.87% (1 720/12 403). The prevalence of IDA in the first, second trimester and third trimester were 1.96% (20/1 019), 8.40%(293/3 487)and 17.82%(1 407/7 897), respectively(P<0.01). The prevalence of standardized ID and IDA were significantly different in various regions of China(P<0.01). The standardized prevalence of ID were relatively higher in East China and Northeast China, 57.37% and 53.41% respectively, while it was the lowest in Southwest China, 30.51%. The standardized prevalence of IDA in South Central, Northwest, and East China were relatively high, 21.30%, 16.97% and 17.53% respectively, and the standardized prevalence of IDA in Southwest China was the lowest, 5.44%,the differents in various regions were significant(all P<0.01). Conclusion The current phenomenon of ID and IDA in pregnant women is still very common,and nutrition and health care during pregnancy should be strengthened.

Objective To study the clinical features and risk factors of acute pulmonary reperfusion injury after operation in neonates with severe pulmonary stenosis or pulmonary atresia.Method From February 2014 to February 2018,a retrospective analysis was performed in patients with critical pulmonary stenosis or pulmonary atresia who received percutaneous balloon pulmonary valvuloplasty (PBPV) in the neonatal intensive care unit of our hospital.Clinical characteristics,perioperative cardiac structure,hemodynamic data and biochemical results were collected.The neonates were assigned into injury group if they had acute lung reperfusion injury,and non-injury group if not.The risk factors of acute lung reperfusion injury were analyzed using multi-variate Logistic regression model.Result A total of 32 patients (24 prenatal diagnosis and 8 postnatal diagnosis) with severe pulmonary stenosis or pulmonary atresia with intact ventricular septum were enrolled.The main manifestations were dyspnea and cyanosis.Intravenous prostaglandin E was administered to keep the ductus arteriosus open.The age of operation ranged from 1 to 52 days and the median age was 7.5 days.Postoperative acute lung reperfusion injury occurred in 7 cases (21.9％).Preoperative and intraoperative pulmonary valve annulus diameter,balloon diameter,preoperative hemoglobin,hematocrit and blood albumin were significantly lower in the injury group.The operation duration,total length of hospital stay and postoperative duration were longer than in the non-injury group,the differences were statistically significant (P ＜ 0.05).Multi-variate Logistic regression analysis showed that the diameter of pulmonary valve annulus (OR =5.814,95％CI 1.106 ～30.568),preoperative blood albumin (OR =1.361,95％ CI 1.063 ～ 1.742),and hematocrit (OR =1.173,95％ CI 1.010 ～ 1.363) were risk factors of acute lung reperfusion injury,with statistically significant differences (P ＜ 0.05).Conclusion Acute lung reperfusion injury is one of the common complications after the operation of severe pulmonary stenosis or pulmonary atresia.The severity of pulmonary valve annulus stenosis,preoperative hematocrit and blood albumin level may be the risk factors of postoperative acute lung reperfusion injury.

BACKGROUND: Micro-nano-sized modification of the material surface provides an effective way to enhance the endothelialization of cardiovascular implants. Shear stress plays an important role in the endothelialization of cardiovascular implants.OBJECTIVE: To review the effects of flow shear stress on endothelial cell cytoskeleton alignment, migration, adhesion and apoptosis on the micropatterned substrates.METHODS: The author performed a retrieval of PubMed and CNKI databases from 2002 to 2017 to search literatures about the effects of shear stress on endothelial cells on the micropatterned substrates. The keywords were micrometer topology, micropattern, flow shear stress, endothelial cells in English and Chinese, respectively.RESULTS AND CONCLUSION: The shear stress parallel to the long axis of the micropattern which is applied to the endothelial cells on micropatterned substrates promotes endothelial cell microfilaments alignment along the long axis direction of micropattern, strengthens endothelial cell migration along the flow direction, increases the level of FAK phosphorylation, enhances endothelial cell adhesion, and improves endothelial cell activity. However, there are some controversies on the effects of parallel shear stress on the microtubule arrangement of endothelial cells on micropatterned substrates. Some studies have reported that parallel shear stress promotes endothelial cell microtubules alignment along the long axis of micropatterns. But others have found that parallel shear stress has no effect on endothelial cell microtubule arrangement. There are different conclusions about the effects of shear stress perpendicular to the long axis of the micropattern on endothelial cells on the micropatterned substrates. Some literatures have found vertical shear stress destroys the structure of endothelial cell microfilaments and microtubules,weakens the degree of microfilaments and microtubules arranged along the long axis of micropatterns, and attenuates endothelial cell adhesion and cell activity. But some have found vertical shear stress does not destroy the structure and alignment of endothelial cell microfilaments and microtubules, and still can promote endothelial cell migration along the flow direction. The magnitude of shear force affects endothelial cell migration, and the number of endothelial cells on the micropatterned substrates migrating along the flow direction increases with the increasing intensity of shear stress.