AIM: To provide scientific evidence for prevention and controlling of cryptosporidiosis, the infection of Cryptosporidium parvum and its epidemiological characteristics were studied in some areas of Anhui Province. ME...AIM: To provide scientific evidence for prevention and controlling of cryptosporidiosis, the infection of Cryptosporidium parvum and its epidemiological characteristics were studied in some areas of Anhui Province. METHODS: The oocyst of Cryptosporidium parvum in 5421 fresh stool samples from eleven areas of Anhui Province was tested by auramine-phenol stain and improved anti-acid stain respectively. The specific antibody of IgG, IgM and T subsets of 41 patients with positive Cryptosporidium parvum in stools were detected by ELISA and biotin-streptavidin (BSA) respectively. RESULTS: The total infective rate of Cryptosporidium parvum was 1.33% (74/5421). Among them, the positive rates of oocyst in the areas of Huaibei (1.82%) and Fuyang (1.80%) were higher. The positive rates of oocyst in stools of infants, pupils, middle school students, college students, adults, patients with diarrhea, and those with immunodeficiency were 3.15%(28/889), 0.82% (9/1098), 0.82%(9/1092), 0.83%(8/969), 0.85% (9/1095), 2.88%(8/278) and 8.33%(3/36)% respectively. The positive rates of oocyst in infants and the patients with diarrhea and immunodeficiency were significantly higher than those in controls (P【0.01). The positive rate of oocyst in males was similar to that in females (P】0.05). The positive rate of oocyst in urban areas (1.13%) was significantly lower than those in rural areas (1.72%, P【0.01). The positive rates of specific IgG, IgM and IgG+IgM in sera of the patients with positive oocyst in stool were 63.4% (26/41), 17.1% (7/41), 19.5% (8/41) respectively. The number fractions of T subsets of CD(3)(+), CD(4)(+), CD(8)(+) and CD(4)(+)/CD(8)(+) of the patients were 0.66+/-0.07, 0.44+/-0.06, 0.28+/-0.04 and 1.58+/-0.32 respectively. The difference between the patients and the controls was significant (P【0.05). The main manifestations of the patients were subclinical infection, in forms of slight abdominal pain, mild diarrhea, and loose stool. CONCLUSION: There are two infection peaks in infection of Cryptosporidium parvum and its infection can be found more often in infants, patients with diarrhea or immunodeficiency, and in rural areas. Subclinical infection is the main manifestation and might be easily misdiagnosed. When the therapeutic effectiveness is low for diarrhea, the infection of Cryptosporidium parvum should be considered, concerning their age and immune function.展开更多
Soil and water loss is now a major environmental problem in many areas of China, especially in the area of the Dabie Mountain, Anhui Province, which results in environmental degradation and does harm to the people's ...Soil and water loss is now a major environmental problem in many areas of China, especially in the area of the Dabie Mountain, Anhui Province, which results in environmental degradation and does harm to the people's life and production there. Based on the observational records from the Dasha River, the authors analyze the character of the variation in flow and sediment in different flood and dry seasons from 1970 to 2000. The result shows that human activities had significantly reduced the sediment discharge and sediment module, and increased the runoff in low-water seasons since the 1980s. The average contribution rate ofhnman activities to decreasing sediment was 65.67%, and at the same period the contribution rate of runoff and rainfall was about 34.33%. Therefore, it is necessary to take the biological and engineering measures to solve the problem of soil and water loss in the Dasha River watershed.展开更多
We generalize a simple model for superlattices to include the effect of differential capacitance. It is shown that the model always has a stable steady-state solution (SSS) if all differential capacitances are posit...We generalize a simple model for superlattices to include the effect of differential capacitance. It is shown that the model always has a stable steady-state solution (SSS) if all differential capacitances are positive. On the other hand, when negative differential capacitance is included, the model can have no stable SSS and be in a self-sustained current oscillation behavior. Therefore, we find a possible minimum toy model with both negative differential resistance and negative differential capacitance which can include the phenomena of both self-sustained current oscillation and I-V oscillation of stable SSSs.展开更多
文摘AIM: To provide scientific evidence for prevention and controlling of cryptosporidiosis, the infection of Cryptosporidium parvum and its epidemiological characteristics were studied in some areas of Anhui Province. METHODS: The oocyst of Cryptosporidium parvum in 5421 fresh stool samples from eleven areas of Anhui Province was tested by auramine-phenol stain and improved anti-acid stain respectively. The specific antibody of IgG, IgM and T subsets of 41 patients with positive Cryptosporidium parvum in stools were detected by ELISA and biotin-streptavidin (BSA) respectively. RESULTS: The total infective rate of Cryptosporidium parvum was 1.33% (74/5421). Among them, the positive rates of oocyst in the areas of Huaibei (1.82%) and Fuyang (1.80%) were higher. The positive rates of oocyst in stools of infants, pupils, middle school students, college students, adults, patients with diarrhea, and those with immunodeficiency were 3.15%(28/889), 0.82% (9/1098), 0.82%(9/1092), 0.83%(8/969), 0.85% (9/1095), 2.88%(8/278) and 8.33%(3/36)% respectively. The positive rates of oocyst in infants and the patients with diarrhea and immunodeficiency were significantly higher than those in controls (P【0.01). The positive rate of oocyst in males was similar to that in females (P】0.05). The positive rate of oocyst in urban areas (1.13%) was significantly lower than those in rural areas (1.72%, P【0.01). The positive rates of specific IgG, IgM and IgG+IgM in sera of the patients with positive oocyst in stool were 63.4% (26/41), 17.1% (7/41), 19.5% (8/41) respectively. The number fractions of T subsets of CD(3)(+), CD(4)(+), CD(8)(+) and CD(4)(+)/CD(8)(+) of the patients were 0.66+/-0.07, 0.44+/-0.06, 0.28+/-0.04 and 1.58+/-0.32 respectively. The difference between the patients and the controls was significant (P【0.05). The main manifestations of the patients were subclinical infection, in forms of slight abdominal pain, mild diarrhea, and loose stool. CONCLUSION: There are two infection peaks in infection of Cryptosporidium parvum and its infection can be found more often in infants, patients with diarrhea or immunodeficiency, and in rural areas. Subclinical infection is the main manifestation and might be easily misdiagnosed. When the therapeutic effectiveness is low for diarrhea, the infection of Cryptosporidium parvum should be considered, concerning their age and immune function.
基金Under the auspices of the Natural Science Foundation of Anhui Education Office (No. 2006KJ161C), Special FundProject of Anhui Provincial Irrigation Office (No. 2001-11)
文摘Soil and water loss is now a major environmental problem in many areas of China, especially in the area of the Dabie Mountain, Anhui Province, which results in environmental degradation and does harm to the people's life and production there. Based on the observational records from the Dasha River, the authors analyze the character of the variation in flow and sediment in different flood and dry seasons from 1970 to 2000. The result shows that human activities had significantly reduced the sediment discharge and sediment module, and increased the runoff in low-water seasons since the 1980s. The average contribution rate ofhnman activities to decreasing sediment was 65.67%, and at the same period the contribution rate of runoff and rainfall was about 34.33%. Therefore, it is necessary to take the biological and engineering measures to solve the problem of soil and water loss in the Dasha River watershed.
基金The project supported by National Natural Science Foundation of China under Grant No. 10347101 and the Grant from Beijing Normal University
文摘We generalize a simple model for superlattices to include the effect of differential capacitance. It is shown that the model always has a stable steady-state solution (SSS) if all differential capacitances are positive. On the other hand, when negative differential capacitance is included, the model can have no stable SSS and be in a self-sustained current oscillation behavior. Therefore, we find a possible minimum toy model with both negative differential resistance and negative differential capacitance which can include the phenomena of both self-sustained current oscillation and I-V oscillation of stable SSSs.