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151.
INTRODUCTION In addition to the prototypical retroviral Gag, Pol, and Env proteins, HIV-1 produces six additional proteins, i.e., Tat, Rev, Nef, Vif, Vpr and Vpu (Fig. 1, adapted from [1]). While Tat and Rev are required for viral replication, Nef, Vif, V…  相似文献   
152.
China has come a long way in fighting against its HIV/AIDS epidemic. The Chinese government has taken an active role in combating this detrimental disease and such a welcome attitude by the Chinese government will certainly provide a positive spin on its …  相似文献   
153.
DIAGNOSIS OF HIV-1 INFECTION The diagnosis of HIV infection is most commonly ac- complished using tests to detect antibody to HIV using a screening test, followed by a supplemental test for confirmation. However, in many countries, including China, screen…  相似文献   
154.
The new cytoplasmic male sterile (CMS) line Yewei A and its maintainer line Yewei B, with better agronomic characteristics, have been developed from a mutant of V20B (a rice maintainer line) through transformation of genomic DNA of wild rice (Oryza minuta J. S. Presl. ex C. B. Presl.). Analysis of molecular markers, DNA sequences, and Southern blot revealed that high DNA polymorphism exists between the mutant and its receptor, indicating that the special DNA fragment from O. minuta may be integrated into the genome of Yewei B. Therefore, transformation of genomic DNA from distant relatives to the plant of a target receptor may open an avenue for creating a new rice germplasm.  相似文献   
155.
Ovarian cancer is an important gynecological tumor, with the third highest morbidity rate and highest mor-tality rate in gynecological cancers, of which the 5-year survival rate remains at only 19%―38.7%[1]. Tumors occurring in ovary can hardly be diagnosed in the early stages for the dormant start, and approxi-mately 70% patients cannot get the final diagnosis until the advanced stages. Surgical operation and post-operational chemotherapy based on cisplatin have become the primary treatment …  相似文献   
156.
Critical to the implementation and scale-up of successful antiretroviral therapy worldwide is an understanding of theefficacy,toxicities and durability of antiretroviral regimens in the specific populations,which they are utilized.In orderto obtain this i…  相似文献   
157.
Severe fever with thrombocytopenia syndrome(SFTS) is an emerging hemorrhagic fever in rural areas of China and is caused by a new bunyavirus,SFTSV,named after the disease.The transmission vectors and animal hosts of SFTSV are unclear.Ticks are the most likely transmission vectors and domestic animals,including goats,dogs,and cattle,are potential amplifying hosts of SFTSV.The clinical symptoms of SFTS are nonspecific,but major symptoms include fever,gastrointestinal symptoms,myalgia,dizziness,joint pain,chills,and regional lymphadenopathy.The most common abnormalities in laboratory test results are thrombocytopenia(95%),leukocytopenia(86%),and elevated levels of serum alanine aminotransferase,aspartate aminotransferase,creatine kinase,and lactate dehydrogenase.The fatality rate for SFTS is 12% on average,and the annual incidence of the disease is approximately five per 100000 of the rural population.  相似文献   
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159.
Most research on micronutrients in maize has focused on maize grown as a monocrop. The aim of this study was to determine the effects of intercropping on the concentrations of micronutrients in maize grain and their acquisition via the shoot. We conducted field experiments to investigate the effects of intercropping with turnip (Brassica campestris L.), faba bean (Vicia faba L.), chickpea (Cicer arietinum L.), and soybean (Glycine max L.) on the iron (Fe), manganese (Mn), copper (Cu) and zinc (Zn) concentrations in the grain and their acquisition via the above-ground shoots of maize (Zea mays L.). Compared with monocropped maize grain, the grain of maize intercropped with legumes showed lower concentrations of Fe, Mn, Cu, and Zn and lower values of their corresponding harvest indexes. The micronutrient concentrations and harvest indexes in grain of maize intercropped with turnip were the same as those in monocropped maize grain. Intercropping stimulated the above-ground maize shoot acquisition of Fe, Mn, Cu and Zn, when averaged over different phosphorus (P) application rates. To our knowledge, this is the first report on the effects of intercropping on micronutrient concentrations in maize grain and on micronutrients acquisition via maize shoots (straw+grain). The maize grain Fe and Cu concentrations, but not Mn and Zn concentrations, were negatively correlated with maize grain yields. The concentrations of Fe, Mn, Cu, and Zn in maize grain were positively correlated with their corresponding harvest indexes. The decreased Fe, Mn, Cu, and Zn concentrations in grain of maize intercropped with legumes were attributed to reduced translocation of Fe, Mn, Cu, and Zn from vegetative tissues to grains. This may also be related to the delayed senescence of maize plants intercropped with legumes. We conclude that turnip/maize intercropping is beneficial to obtain high maize grain yield without decreased concentrations of Fe, Mn, Cu, and Zn in the grain. Further research is required to clarify the mechanisms underlying the changes in micronutrient concentrations in grain of intercropped maize.  相似文献   
160.
This study compared the accumulation of Zn2+and Cu2+in the ovaries and ova of loaches under different concentrations of Zn2+(1.00, 2.50 and 5.00 mg/L respectively) and Cu2+(0.10, 0.25 and 0.50 mg/L respectively). The results showed that both Zn2+and Cu2+accumulated in the ovaries, and that the relationship between accumulation and time was linear over 20 days of exposure. The accumulation of the metals in ovaries was closely related to the concentration of exposure in the solutions(P<0.05), and was obviously affected by the time and doses. However, the Cu2+concentration was significantly higher than Zn2+(P<0.05). The development level of ova in the ovaries also correlated with the concentration and exposure period in the Zn2+and Cu2+solutions.  相似文献   
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