[Objective]The research aimed to test and identify the physicochemical characters and antiviral activity in vitro of semi-finished product of the recombinant porcine rPoIFN-α. [Method]HEp-2/VSV system was used to tes...[Objective]The research aimed to test and identify the physicochemical characters and antiviral activity in vitro of semi-finished product of the recombinant porcine rPoIFN-α. [Method]HEp-2/VSV system was used to test the antiviral activity of three batches of rPoIFN-α. Using recombinant human IFN-α as reference,the titer of interferon was measured. The semi-finished product of rPoIFN-α with the known titer were treated with 0.25% trypsin,HCl and mouse anti-porcine IFN-α monoclonal antibody. And the anti-viral activity of each batch of rPoIFN-α was detected. The physicochemical characters of rPoIFN-α were evaluated. The inhibition of induced cytopathic effect of rPoIFN-α on PPV (Porcine parvovirus) and PRV (Porcine pseudorabies) on swine kidney cell (PK-15) was determined. And the antiviral activity of rPoIFN-α in vitro was observed. [Result]The titers of semi-finished products of rPoIFN-α titrated by HEp-2/VSV system could reach 1.5×105 IU/ml,with the specific activity of 1.1×106 IU/mg. The residual rate of the tier of rPoIFN-α treated by 0.25% trypsin at 37 ℃ for 1 h was less than 1%. And that treated with HCl (pH of 2.0) for 72 h was up to 95%. And that treated at 56 ℃ for 30 min and that treated by mouse anti-porcine IFN-α monoclonal antibody at 37 ℃ for 1 h were higher than 47% and about 1% respectively. The antiviral test in vitro showed that 50 and 500 IU/ml rPoIFN-α could inhibit the induced cytopathic effect of PRV and PPV on PK-15 cell lines. [Conclusion]rPoIFN-α had the basic physicochemical characters of IFN-α. And it could inhibit the induced cytopathic effect of PRV and PPV on PK-15 cell lines,but there was dosage difference.展开更多
Crohn's disease and ulcerative colitis can be grouped as the inflammatory bowel diseases (IBD). These conditions have become increasingly common in recent years, including in children and young people. Although muc...Crohn's disease and ulcerative colitis can be grouped as the inflammatory bowel diseases (IBD). These conditions have become increasingly common in recent years, including in children and young people. Although much is known about aspects of the pathogenesis of these diseases, the precise aetiology is not yet understood, and there remains no cure. Recent data has illustrated the importance of a number of genes-several of these are important in the onset of IBD in early life, including in infancy. Pain, diarrhoea and weight loss are typical symptoms of paediatric Crohn's disease whereas bloody diarrhoea is more typical of colitis in children. However, atypical symptoms may occur in both conditions: these include isolated impairment of linear growth or presentation with extra-intestinal manifestations such as erythma nodosum. Growth and nutrition are commonly compromised at diagnosis in both Crohn's disease and colitis. Consideration of possible IBD and completion of appropriate investigations are essential to ensure prompt diagnosis, the- reby avoiding the consequences of diagnostic delay. Patterns of disease including location and progression of IBD in childhood differ substantially from adult- onset disease. Various treatment options are available for children and adolescents with IBD. Exclusive enteral nutrition plays a central role in the induction of remission of active Crohn's disease. Medical and surgical therapies need to considered within the context of a growing and developing child. The overall management of these chronic conditions in children should include multi-disciplinary expertise, with focus upon maintaining control of gut inflammation, optimising nutrition, growth and quality of life, whilst preventing disease or treatment-related complications.展开更多
AIM: To report the clinicopathological features and magnetic resonance imaging (MRI) findings of solid and pseudopapillary tumor (SPT) of pancreas.METHODS: From 1981 to 2005, 26 surgically treated cases of SPT were re...AIM: To report the clinicopathological features and magnetic resonance imaging (MRI) findings of solid and pseudopapillary tumor (SPT) of pancreas.METHODS: From 1981 to 2005, 26 surgically treated cases of SPT were retrospectively reviewed. MRI findings of the latest 11 consecutive SPT cases were investigated.RESULTS: There were 25 women and one man having SPT (median age: 23 year) with a median tumor size of 7.5 cm. Among them, nine patients developed solid pseudopapillary carcinoma. During the median follow-up period of 66 mo, the 5-year survival rate of the 26 SPT patients was 96.2%. Three MRI features were proposed including Type 1 image, displaying SPT with completely solid part. All SPT patients with type 1 image were detected incidentally. Type 2 image displays of SPT with solid mass hemorrhage and type 3 image with massive hemorrhage. All the eight SPT patients with type 2 and 3 images suffered abdominal pain due to hemorrhage from SPT.CONCLUSION: SPT had a favorable survival rate irrespective of surgical procedures, malignancy, and MRI findings, however, MRI could reliably correlate with its clinicopathological features.展开更多
The diagnosis of cystadenoma is rare, even more so when located in the extrahepatic bile duct. Unspecific clinical signs may lead this pathology to be misdiagnosed. The need for pathological anatomy in order to distin...The diagnosis of cystadenoma is rare, even more so when located in the extrahepatic bile duct. Unspecific clinical signs may lead this pathology to be misdiagnosed. The need for pathological anatomy in order to distinguish cystadenomas from simple biliary cysts is crucial. The most usual treatment nowadays is resection of the bile duct, together with cholecystectomy and Roux-en-Y reconstruction.展开更多
AIM: To compare the effects of He/icobacter py/ori (Hpylon) infection on gastropathy between Indonesian and Japanese patients. METHODS: Biopsy specimens were obtained during upper gastrointestinal endoscopy from 1...AIM: To compare the effects of He/icobacter py/ori (Hpylon) infection on gastropathy between Indonesian and Japanese patients. METHODS: Biopsy specimens were obtained during upper gastrointestinal endoscopy from 167 subjects (125 Indonesians and 42 Japanese) with uninvestigated symptoms of dyspepsia. The specimens were analyzed for the presence of H pylori using urease analysis, histopathology, and cell culture. The grade and activity of gastritis was assessed using the updated Sydney system. RESULTS: The percentages of Indonesian and Japanese patients who were H py/ori-positive at the antrum or body of the stomach were similar (68% and 59.5%, respectively; P = 0.316). Of those who were Hpylori-positive, more Japanese patients than Indonesian patients had high levels of polymorphonuclear cells (P = 0.001), mononuclear cells (P = 0.013), glandular atrophy (P = 0.000), and intestinal metaplasia (P = 0.011) in both the antrum and body of the stomach. CONCLUSION: The grade of gastritis and prevalence of mucosal atrophy and intestinal metaplasia were higher in Japanese patients. The difference between Indonesian and Japanese patients was significant.展开更多
According to clinical and pathological observation in infectious serositis of duck, the main signs of this disease were diarrhoea, breathing with difficulty, head tremble and movement beyond coordination. The patholog...According to clinical and pathological observation in infectious serositis of duck, the main signs of this disease were diarrhoea, breathing with difficulty, head tremble and movement beyond coordination. The pathological changes that had been found in 30 experimental ducks were fibrous pericarditis, hepatitis, and encephalitis. The fibrous serositis, liver fatty degeneration or focus necrosis,nonsuppurative encephalitis and serous-fibrous pneumonia were typical pathological changes of histology.展开更多
The possible causes of condyloma acuminatarecurrence arc summarized: such as patients with cellularimmune denciencies, physical therapy triggering subclinicalinfective foci, sowing of the virus particles, and insuffic...The possible causes of condyloma acuminatarecurrence arc summarized: such as patients with cellularimmune denciencies, physical therapy triggering subclinicalinfective foci, sowing of the virus particles, and insufficienttherapy. Corresponding preventive measures are addressed,including: immunomodulators improving cellular immunity,ensuring the range and depth of physical therapy, and trcatingsexual partners simultaneously.展开更多
Objectives:The purpose of this study was to describe relationships between negative emotions and perceived emotional support in parents of children admitted to the pediatric intensive care unit(PICU).Methods:This cros...Objectives:The purpose of this study was to describe relationships between negative emotions and perceived emotional support in parents of children admitted to the pediatric intensive care unit(PICU).Methods:This cross-sectional descriptive study conducted face-to-face interviews between January 2019 and January 2020.Study variables included depression(PHQ-9 Scale),anxiety(Emotional Distress-Anxiety-Short Form 8a),anger(Emotional Distress-Anger-Short Form 5a),fear(Fear-Affect Computerized Adaptive Test),somatic fear(Fear-Somatic Arousal-Fixed Form),loneliness(Revised 20-item UCLA Loneliness Scale),and perceived emotional support(Emotional Support-Fixed Form).Results:Eighty parents reported symptoms of depression 8.00(4.00,13.75),anxiety(23.43±7.80),anger(13.40±5.46),fear(72.81±27.26),somatic fear 9.00(6.00,12.75),loneliness(39.35±12.00),and low perceived emotional support(32.14±8.06).Parents who were young,single,low-income,and with limited-post secondary education reported greater loneliness and lower perceived emotional support.Fear correlated with depression(r=0.737,P<0.01)and anxiety(r=0.900,P<0.01).Inverse relationships were discovered between perceived emotional support and loneliness(r=-0.767,P<0.01),anger(r=-0.401,P<0.01),and depression(r=-0.334,P<0.01).Conclusions:The cluster of negative emotions identified will serve as potential targets for future interventions designed to enhance support for parents of critically ill children.展开更多
Objective: Infection of human papillomavirus in condylomaacuminatum (CA) was detected by real time fluorescencequantitative PCR (FQ-PCR) technique. Methods: Specimens of CA-DNA quantification from 94cases were examine...Objective: Infection of human papillomavirus in condylomaacuminatum (CA) was detected by real time fluorescencequantitative PCR (FQ-PCR) technique. Methods: Specimens of CA-DNA quantification from 94cases were examined by real time FQ-PCR technique and 32cases were compared with the same method after 10-daystreatment. Results: CA-DNA was found in all patients, with an averageof 4.0×10^6 copies/ul. After 10 days of treatment, the averagewas 2.1×10^5 copies/ul. There was a significant difference inthe average amount of CA-DNA before and after thetreatment. Conclusion: Real time FQ-PCR is a good method forexamining CA-DNA amount and it can direct the treatment of CA.展开更多
Biliary adenoma is uncommon benign neoplasm of the biliary system, of unknown aetiology and account for approximately 0.1%-2% of all gastrointestinal benign tumors. Most of patients are asymptomatic; a few patients ha...Biliary adenoma is uncommon benign neoplasm of the biliary system, of unknown aetiology and account for approximately 0.1%-2% of all gastrointestinal benign tumors. Most of patients are asymptomatic; a few patients have mild jaundice or abdominal discomfort. To our knowledge, there were only a few cases of biliary papillomatosis reported in the previous literatures, which only showed solitary tumor in bile duct. We presented a rare case with multiple biliary adenomas in extrahepatic bile duct confirmed by endoscopic retrograde cholangiopancreatography(ERCP) and histopathology. After 3 months follow-up, the patient remained asymptomatic.展开更多
The Yellow Emperor's Classic of Internal Medicine (黄帝内经素问Huangdi Neijing Suwen), created in the Warring States period (475 to 221 BC) described a phenomenon whereby the eastern, western, northern, southern, ...The Yellow Emperor's Classic of Internal Medicine (黄帝内经素问Huangdi Neijing Suwen), created in the Warring States period (475 to 221 BC) described a phenomenon whereby the eastern, western, northern, southern, and central regions were liable to different diseases. It brought forward the principle of treatment in accordance with local conditions. Lv's Spring and Autumn Annals, Huai Nan Tzu (Huainanzi), and the Regiment of Health (Yangshenglun) in the Qin, Han, Wei, Jin, and Southern and Northern Dynasties all describe regional diseases such as goiter (endemic goiter) and yellowish teeth (dental fluorosis) as being caused by geologic and climatic factors. Zhang (miasma), first mentioned in the Han Dynasty, was considered related to the summer heat and dampness particular to the geographical environment of the south. Zhang was further associated with malaria in the Jin Dynasty. General Treatise on the Etiology and Symptomology of Diseases (Zhubingyuanhou Lun), in the Sui Dynasty, held that as a type of poisonous gas, Zhang was the predisposing cause of malaria, seasonal disease, and barbiers, among other conditions. General Guide (Zhinan Zonglun), in the Southern Song Dynasty, regarded Zhang malaria as a separate disease. Healthy Prescription in the Southern Wuling District (Lingnan Weisheng Fang), in the late Song and early Yuan Dynasties, explicitly put forward the concepts of cold Zhang, hot Zhang, and lockjaw Zhang. Guidelines for Treatment of Zhang Malaria (Zhangnue Zhinan), in the Ming Dynasty, maintained that cold Zhang was equivalent to malaria, while hot Zhang and lockjaw Zhang were equivalent to cold damage, the latter of which can be treated by prescriptions for cold damage. Records on Zhang gas and Zhang disease decreased during the Ming and Qing Dynasties.展开更多
In this paper, we investigate the spatiotemporal dynamics of a reactio^diffusion epi- demic model with zero-flux boundary conditions. The value of our study lies in two aspects: mathematically, by using maximum princ...In this paper, we investigate the spatiotemporal dynamics of a reactio^diffusion epi- demic model with zero-flux boundary conditions. The value of our study lies in two aspects: mathematically, by using maximum principle and the linearized stability theory, a priori estimates of the steady state system and the local asymptotic stability of positive constant solution are given. By using the implicit function theorem, the exis- tence and nonexistence of nonconstant positive steady states are shown. Applying the bifurcation theory, the global bifurcation structure of nonconstant positive steady states is established. Epidemiologically, through numerical simulations, under the conditions of the existence of nonconstant positive steady states, we find that the smaller the space, the easier the pattern formation; the bigger the diffusion, the easier the pattern formation. These results are beneficial to disease control, that is, we must do our best to control the diffusion of the infectious to avoid disease outbreak.展开更多
基金Supported by Natural Science Research Project of Anhui Educational Committee (2004kj218 )Major Special Program of Science and Technology Grand Plan of Anhui Province (08010302179)~~
文摘[Objective]The research aimed to test and identify the physicochemical characters and antiviral activity in vitro of semi-finished product of the recombinant porcine rPoIFN-α. [Method]HEp-2/VSV system was used to test the antiviral activity of three batches of rPoIFN-α. Using recombinant human IFN-α as reference,the titer of interferon was measured. The semi-finished product of rPoIFN-α with the known titer were treated with 0.25% trypsin,HCl and mouse anti-porcine IFN-α monoclonal antibody. And the anti-viral activity of each batch of rPoIFN-α was detected. The physicochemical characters of rPoIFN-α were evaluated. The inhibition of induced cytopathic effect of rPoIFN-α on PPV (Porcine parvovirus) and PRV (Porcine pseudorabies) on swine kidney cell (PK-15) was determined. And the antiviral activity of rPoIFN-α in vitro was observed. [Result]The titers of semi-finished products of rPoIFN-α titrated by HEp-2/VSV system could reach 1.5×105 IU/ml,with the specific activity of 1.1×106 IU/mg. The residual rate of the tier of rPoIFN-α treated by 0.25% trypsin at 37 ℃ for 1 h was less than 1%. And that treated with HCl (pH of 2.0) for 72 h was up to 95%. And that treated at 56 ℃ for 30 min and that treated by mouse anti-porcine IFN-α monoclonal antibody at 37 ℃ for 1 h were higher than 47% and about 1% respectively. The antiviral test in vitro showed that 50 and 500 IU/ml rPoIFN-α could inhibit the induced cytopathic effect of PRV and PPV on PK-15 cell lines. [Conclusion]rPoIFN-α had the basic physicochemical characters of IFN-α. And it could inhibit the induced cytopathic effect of PRV and PPV on PK-15 cell lines,but there was dosage difference.
文摘Crohn's disease and ulcerative colitis can be grouped as the inflammatory bowel diseases (IBD). These conditions have become increasingly common in recent years, including in children and young people. Although much is known about aspects of the pathogenesis of these diseases, the precise aetiology is not yet understood, and there remains no cure. Recent data has illustrated the importance of a number of genes-several of these are important in the onset of IBD in early life, including in infancy. Pain, diarrhoea and weight loss are typical symptoms of paediatric Crohn's disease whereas bloody diarrhoea is more typical of colitis in children. However, atypical symptoms may occur in both conditions: these include isolated impairment of linear growth or presentation with extra-intestinal manifestations such as erythma nodosum. Growth and nutrition are commonly compromised at diagnosis in both Crohn's disease and colitis. Consideration of possible IBD and completion of appropriate investigations are essential to ensure prompt diagnosis, the- reby avoiding the consequences of diagnostic delay. Patterns of disease including location and progression of IBD in childhood differ substantially from adult- onset disease. Various treatment options are available for children and adolescents with IBD. Exclusive enteral nutrition plays a central role in the induction of remission of active Crohn's disease. Medical and surgical therapies need to considered within the context of a growing and developing child. The overall management of these chronic conditions in children should include multi-disciplinary expertise, with focus upon maintaining control of gut inflammation, optimising nutrition, growth and quality of life, whilst preventing disease or treatment-related complications.
文摘AIM: To report the clinicopathological features and magnetic resonance imaging (MRI) findings of solid and pseudopapillary tumor (SPT) of pancreas.METHODS: From 1981 to 2005, 26 surgically treated cases of SPT were retrospectively reviewed. MRI findings of the latest 11 consecutive SPT cases were investigated.RESULTS: There were 25 women and one man having SPT (median age: 23 year) with a median tumor size of 7.5 cm. Among them, nine patients developed solid pseudopapillary carcinoma. During the median follow-up period of 66 mo, the 5-year survival rate of the 26 SPT patients was 96.2%. Three MRI features were proposed including Type 1 image, displaying SPT with completely solid part. All SPT patients with type 1 image were detected incidentally. Type 2 image displays of SPT with solid mass hemorrhage and type 3 image with massive hemorrhage. All the eight SPT patients with type 2 and 3 images suffered abdominal pain due to hemorrhage from SPT.CONCLUSION: SPT had a favorable survival rate irrespective of surgical procedures, malignancy, and MRI findings, however, MRI could reliably correlate with its clinicopathological features.
文摘The diagnosis of cystadenoma is rare, even more so when located in the extrahepatic bile duct. Unspecific clinical signs may lead this pathology to be misdiagnosed. The need for pathological anatomy in order to distinguish cystadenomas from simple biliary cysts is crucial. The most usual treatment nowadays is resection of the bile duct, together with cholecystectomy and Roux-en-Y reconstruction.
文摘AIM: To compare the effects of He/icobacter py/ori (Hpylon) infection on gastropathy between Indonesian and Japanese patients. METHODS: Biopsy specimens were obtained during upper gastrointestinal endoscopy from 167 subjects (125 Indonesians and 42 Japanese) with uninvestigated symptoms of dyspepsia. The specimens were analyzed for the presence of H pylori using urease analysis, histopathology, and cell culture. The grade and activity of gastritis was assessed using the updated Sydney system. RESULTS: The percentages of Indonesian and Japanese patients who were H py/ori-positive at the antrum or body of the stomach were similar (68% and 59.5%, respectively; P = 0.316). Of those who were Hpylori-positive, more Japanese patients than Indonesian patients had high levels of polymorphonuclear cells (P = 0.001), mononuclear cells (P = 0.013), glandular atrophy (P = 0.000), and intestinal metaplasia (P = 0.011) in both the antrum and body of the stomach. CONCLUSION: The grade of gastritis and prevalence of mucosal atrophy and intestinal metaplasia were higher in Japanese patients. The difference between Indonesian and Japanese patients was significant.
文摘According to clinical and pathological observation in infectious serositis of duck, the main signs of this disease were diarrhoea, breathing with difficulty, head tremble and movement beyond coordination. The pathological changes that had been found in 30 experimental ducks were fibrous pericarditis, hepatitis, and encephalitis. The fibrous serositis, liver fatty degeneration or focus necrosis,nonsuppurative encephalitis and serous-fibrous pneumonia were typical pathological changes of histology.
文摘The possible causes of condyloma acuminatarecurrence arc summarized: such as patients with cellularimmune denciencies, physical therapy triggering subclinicalinfective foci, sowing of the virus particles, and insufficienttherapy. Corresponding preventive measures are addressed,including: immunomodulators improving cellular immunity,ensuring the range and depth of physical therapy, and trcatingsexual partners simultaneously.
基金This work was supported by the West Virginia University School of Nursing Research Investment Fund.
文摘Objectives:The purpose of this study was to describe relationships between negative emotions and perceived emotional support in parents of children admitted to the pediatric intensive care unit(PICU).Methods:This cross-sectional descriptive study conducted face-to-face interviews between January 2019 and January 2020.Study variables included depression(PHQ-9 Scale),anxiety(Emotional Distress-Anxiety-Short Form 8a),anger(Emotional Distress-Anger-Short Form 5a),fear(Fear-Affect Computerized Adaptive Test),somatic fear(Fear-Somatic Arousal-Fixed Form),loneliness(Revised 20-item UCLA Loneliness Scale),and perceived emotional support(Emotional Support-Fixed Form).Results:Eighty parents reported symptoms of depression 8.00(4.00,13.75),anxiety(23.43±7.80),anger(13.40±5.46),fear(72.81±27.26),somatic fear 9.00(6.00,12.75),loneliness(39.35±12.00),and low perceived emotional support(32.14±8.06).Parents who were young,single,low-income,and with limited-post secondary education reported greater loneliness and lower perceived emotional support.Fear correlated with depression(r=0.737,P<0.01)and anxiety(r=0.900,P<0.01).Inverse relationships were discovered between perceived emotional support and loneliness(r=-0.767,P<0.01),anger(r=-0.401,P<0.01),and depression(r=-0.334,P<0.01).Conclusions:The cluster of negative emotions identified will serve as potential targets for future interventions designed to enhance support for parents of critically ill children.
文摘Objective: Infection of human papillomavirus in condylomaacuminatum (CA) was detected by real time fluorescencequantitative PCR (FQ-PCR) technique. Methods: Specimens of CA-DNA quantification from 94cases were examined by real time FQ-PCR technique and 32cases were compared with the same method after 10-daystreatment. Results: CA-DNA was found in all patients, with an averageof 4.0×10^6 copies/ul. After 10 days of treatment, the averagewas 2.1×10^5 copies/ul. There was a significant difference inthe average amount of CA-DNA before and after thetreatment. Conclusion: Real time FQ-PCR is a good method forexamining CA-DNA amount and it can direct the treatment of CA.
文摘Biliary adenoma is uncommon benign neoplasm of the biliary system, of unknown aetiology and account for approximately 0.1%-2% of all gastrointestinal benign tumors. Most of patients are asymptomatic; a few patients have mild jaundice or abdominal discomfort. To our knowledge, there were only a few cases of biliary papillomatosis reported in the previous literatures, which only showed solitary tumor in bile duct. We presented a rare case with multiple biliary adenomas in extrahepatic bile duct confirmed by endoscopic retrograde cholangiopancreatography(ERCP) and histopathology. After 3 months follow-up, the patient remained asymptomatic.
文摘The Yellow Emperor's Classic of Internal Medicine (黄帝内经素问Huangdi Neijing Suwen), created in the Warring States period (475 to 221 BC) described a phenomenon whereby the eastern, western, northern, southern, and central regions were liable to different diseases. It brought forward the principle of treatment in accordance with local conditions. Lv's Spring and Autumn Annals, Huai Nan Tzu (Huainanzi), and the Regiment of Health (Yangshenglun) in the Qin, Han, Wei, Jin, and Southern and Northern Dynasties all describe regional diseases such as goiter (endemic goiter) and yellowish teeth (dental fluorosis) as being caused by geologic and climatic factors. Zhang (miasma), first mentioned in the Han Dynasty, was considered related to the summer heat and dampness particular to the geographical environment of the south. Zhang was further associated with malaria in the Jin Dynasty. General Treatise on the Etiology and Symptomology of Diseases (Zhubingyuanhou Lun), in the Sui Dynasty, held that as a type of poisonous gas, Zhang was the predisposing cause of malaria, seasonal disease, and barbiers, among other conditions. General Guide (Zhinan Zonglun), in the Southern Song Dynasty, regarded Zhang malaria as a separate disease. Healthy Prescription in the Southern Wuling District (Lingnan Weisheng Fang), in the late Song and early Yuan Dynasties, explicitly put forward the concepts of cold Zhang, hot Zhang, and lockjaw Zhang. Guidelines for Treatment of Zhang Malaria (Zhangnue Zhinan), in the Ming Dynasty, maintained that cold Zhang was equivalent to malaria, while hot Zhang and lockjaw Zhang were equivalent to cold damage, the latter of which can be treated by prescriptions for cold damage. Records on Zhang gas and Zhang disease decreased during the Ming and Qing Dynasties.
文摘In this paper, we investigate the spatiotemporal dynamics of a reactio^diffusion epi- demic model with zero-flux boundary conditions. The value of our study lies in two aspects: mathematically, by using maximum principle and the linearized stability theory, a priori estimates of the steady state system and the local asymptotic stability of positive constant solution are given. By using the implicit function theorem, the exis- tence and nonexistence of nonconstant positive steady states are shown. Applying the bifurcation theory, the global bifurcation structure of nonconstant positive steady states is established. Epidemiologically, through numerical simulations, under the conditions of the existence of nonconstant positive steady states, we find that the smaller the space, the easier the pattern formation; the bigger the diffusion, the easier the pattern formation. These results are beneficial to disease control, that is, we must do our best to control the diffusion of the infectious to avoid disease outbreak.