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41.
This study was carried out to clarify the role of lymphocyte subpopulations and Babesia-specific antibody on the treatment of clindamycin in dogs infected with B. gibsoni. Ten beagle dogs were divided into two groups: an untreated group (5 dogs) and a clindamycin-treated group (5 dogs), which was administered clindamycin at 25 mg/ kg body weight, per os, q 12 hr from 7 days to 21 days post-infection (PI). On the acute stage of infection, clindamycin treatment resolved anaemia and other clinical findings. There were no significant differences between treated and untreated dogs either in parasitemia levels or Babesial IgG antibody levels. However, morphological changes that indicated degeneration in the majority of parasites were observed. The numbers of CD4(+) showed a significant increase in treated dogs, especially after treatment. On the chronic stage, CD4(+) cells maintained high level both of the treated and untreated dogs. Although parasitemia maintained low level, their relapses were occurred on the 49th day PI in treated dogs and on the 42nd and 63rd PI in untreated dogs. A rapid humoral antibody response was observed in treated dogs, however, lower humoral antibody responses in untreated dogs after relapses. The antibody levels of treated dogs were significantly higher than those of untreated dogs. These results suggested that clindamycin might not eliminate rapidly parasites from peripheral blood, but damage parasites, which might stimulate efficiently humoral and cellular immunity against Babesia infection, and result in an improvement of clinical conditions.  相似文献   
42.
The effects of various concentrations of maleic hydrazide (MH; 2, 4, 6, 8 mg/l) and three light treatments (16-h, 24-h, 0-h) on in vitro rhizome formation and conservation of ginger (Zingiber officinale Rosc. cv. Rio de Janeiro) were studied. In vitro rhizome formation occurred in all the above treatments. Addition of MH (2–8 mg/l) to the control medium (CM) comprising Murashige and Skoog's (1962) salts, 9% sucrose, 0.8% agar-agar, 0.1 mg/l α-naphthaleneacetic acid (NAA), 1 mg/l N6-benzyladenine (BA), did not show any significant positive effects on rhizome formation as well as survival of cultures. A significant effect of light treatments was observed on survival of cultures but not on rhizome formation. More than 50% cultures survived up to 14 months on CM under 16-h and 24-h light conditions as compared to 20% cultures on same medium incubated under dark. A total of 33 genotypes of cultivated and wild species of Zingiber were subsequently tested for conservation through in vitro rhizome formation on CM under 16-h light condition. All genotypes produced rhizomes of varying size with numbers ranging from 3 to 15 per culture and were conserved for at least 12 months; some genotypes could be conserved even up to 16–20 months. Viability of rhizomes was determined by in vitro regeneration of shoots upon subculture and their subsequent establishment in soil. Following the protocol described in the present paper, some 160 genotypes of cultivated and wild species of Zingiber, collected from different geographical regions of India, are being conserved at In Vitro Genebank of National Bureau of Plant Genetic Resources, New Delhi.  相似文献   
43.
White spot syndrome (WSS) is considered as a great threat to commercial farming of the tiger shrimp (Penaeus monodon). The causal agent of WSS is a DNA virus called white spot syndrome virus (WSSV). The prevalence of this dreadful virus infection has been studied in five randomly selected hatcheries located in the Cox’s Bazar district of Bangladesh. Both one-step and nested polymerase chain reaction (PCR) involving two pairs of primers, namely, 146F1/146R1 and 146F2/146R2, amplifying the 1447 bp and 941 bp fragments, respectively, were conducted to detect the WSSV. Out of 60 randomly collected shrimps, 12 (20%) were found to be positive by one-step PCR, while 18 (30%) were found to be positive by nested PCR. The nested PCR was found to be much more sensitive than the one-step PCR. The shrimp specimens showing clinical signs of WSS were positive for WSSV by both one-step and nested PCR. Some of the apparently healthy samples were also found to be positive for WSSV by nested PCR. Among the two primer-pairs, the inner pair amplifying the 941 bp fragment was more sensitive than the outer primer pair amplifying the 1447 bp fragment when used in one-step PCR.  相似文献   
44.
We investigated the feasibility of using several fast-growing tropical or subtropical hardwood species for timber production by measuring key wood qualities in relationship to the high rates of lateral growth. The trees tested were sampled from even-aged plantations of Acacia mangium, A. auriculiformis, hybrid Acacia (A. mangium × A. auriculiformis), Eucalyptus grandis, E. globulus, and Paraserianthes falcataria (Solomon and Java origin) that had already reached commercial harvesting age. The released strain of the surface growth stress (RS), xylem density (XD), microfibril angle (MFA), and fiber length (FL) were measured at the outermost part of the xylem at breast height in each tree. Results were then compared to the lateral growth rate (radius/age) at breast height, which provides a relative indicator of the amount of tree growth per year. Our findings indicated that RS was constant, regardless of lateral growth rate in each species. Similar results were observed for XD, MFA, and FL, with a few exceptions, suggesting that high growth rates do not intrinsically affect the wood properties of fast-growing tropical or subtropical species that have reached harvesting age. However, special attention must be paid to patterns of xylem maturation when developing plantations of such species.  相似文献   
45.
Methyl parathion is an organophosphate insecticide that has been used in agriculture and domestic for several years. Vitamin C (200 mg/kg bw per day) + vitamin E (200 mg/kg bw per day), methyl parathion (0.28 mg/kg bw per day) and vitamin C (200 mg/kg bw per day) + vitamin E (200 mg/kg bw per day) + methyl parathion (0.28 mg/kg bw per day) combination were given to rats orally via gavage for 7 weeks. Body and kidney weights, malondialdehyde (MDA) levels and histopathological changes were investigated at the end of 4th and 7th weeks comparatively with control group. When methyl parathion-treated group and vitamins C and E + methyl parathion-treated group were compared to control group body and kidney weights decreased significantly at the end of 4th and 7th weeks. MDA levels increased in kidney tissues of the methyl parathion- and vitamins C and E + methyl parathion-treated groups compared to control group. MDA levels decreased significantly in vitamins C and E + methyl parathion treated group compared with methyl parathion treated group at the end of 4th and 7th weeks. In our light microscopic investigations, after 4 weeks of methyl parathion exposure, glomerular atrophy and vascular dilatation, and after 7 weeks, necrosis and edema were observed in the kidney tissues. After 4 weeks of vitamins C and E + methyl parathion exposure, mononuclear cell infiltrations, and after 7 weeks, calcification were detected in the kidney tissues.  相似文献   
46.
In order to identify the alternative effective chemotherapeutic agents for murine babesiosis, some selected drugs were examined for their efficacy against protozoan infection in the mouse-Babesia rodhaini (B. rodhaini) model. Clindamycin was not completely effective for elimination of parasites in a dose of 50 mg or 100 mg/kg BW/day b.i.d. but effective to prolong the life span of hosts, while it completely cured B. rodhaini infections in a dose of 200 mg. On the other hand, a double therapy consisting of 2 treatments with 100 mg clindamycin and 100 mg clindamycin and with 100 mg clindamycin and 100 mg tetracycline; respectively, and a single therapy with 100 mg tetracycline or 200 mg clindamycin, had a possibility to clear away B. rodhaini organisms from hosts. However, almost all the treatment groups, had a relapse of the infection within 10 days post treatment or re-treatment. Cured mice by treatment with clindamycin and clindamycin, or clindamycin and tetracycline showed complete resistance against challenge with B. rodhaini, while mice cured by administration of clindamycin at 200 mg or tetracycline at 100 mg showed incomplete resistance to challenge infection. The present data suggest that the two former chemotherapies can induce effective protective immunity (premunization), but the latter two chemotherapies induce incomplete premunization.  相似文献   
47.
A major limitation to chickpea grown on residual soil moisture after the harvest of rice in the High Barind Tract (HBT) of Bangladesh is acidic surface soil. A diagnostic trial conducted in the 2001/02 season showed that Mo was limiting growth and yield of chickpea. Multilocational on‐farm trials in the 2002/03 season established that Mo applied to the soil at 500 g ha–1 improved nodulation and plant growth and resulted in grain‐yield responses of 58%–173%. In addition, we tested an application method suitable for resource‐poor farmers where Mo and Rhizobium were added in the seed‐priming process. Multilocational trials in farmers' fields in 2003/04 confirmed that this was as effective as soil application of Mo, giving yield responses of 37%–90%. In each of 2004/05 and 2005/06 seasons, 50 farmers implemented on‐farm evaluations of adding Mo + Rhizobium in the priming solution in operational scale plots (666 m2) across the HBT. Mean responses of up to 50%, compared to priming in water only, were obtained. These results suggest that the severe N deficiency of chickpea commonly observed in the HBT can be effectively alleviated by applying Mo and Rhizobium inoculum through a simple low‐cost technology within the scope of resource‐poor farmers.  相似文献   
48.
The objectives of this study were first to show adrenocortical response to a long‐acting adrenocorticotropic hormone preparation (tetracosactide acetate zinc suspension) (ACTH‐Z) and its effect on adrenocortical function in beef cows ( Experiment 1 ) and second to apply the ACTH‐Z challenge in dairy cows based on cortisol concentrations in milk collected at routine milking ( Experiment 2 ). In Experiment 1 , four beef cows in luteal phase were challenged with ACTH‐Z, and plasma cortisol concentrations were determined for 48 h after the injection at 30‐min to 2‐h intervals. A rapid ACTH test was conducted 3 days before and 2 h after the completion of ACTH‐Z injection for 48 h to investigate the effect on adrenocortical function. Plasma cortisol concentrations increased significantly 30 min after ACTH‐Z injection (p < 0.001), and the high cortisol levels were maintained for approximately 10 h after the injection. In Experiment 2 , eight dairy cows were subjected to ACTH‐Z challenge 1–2 weeks and 4–5 weeks post‐partum. Blood and milk samples were taken at morning and afternoon milking. All the cows showed a significant increase in cortisol concentrations in plasma as well as in skim milk 8 h after ACTH‐Z injection 1–2 weeks and 4–5 weeks post‐partum (p < 0.001). There was a significant correlation between plasma and skim milk cortisol concentrations 8 h after ACTH‐Z challenge (r = 0.74, p < 0.001). The results obtained in this study suggest that elevated levels of plasma cortisol are maintained for approximately 10 h after ACTH‐Z treatment without adverse effect on adrenocortical function and a long‐acting ACTH‐Z challenge based on cortisol concentrations in milk, which were collected at the morning and the afternoon milking, can be a useful tool to monitor adrenocortical function in cows.  相似文献   
49.
Precision Agriculture - Profitability analyses of site-specific nitrogen (N) management strategies have often failed to provide satisfying reasons for adoption of precision farming technologies....  相似文献   
50.
Journal of Crop Science and Biotechnology - Cowpea as a low-input crop has a potential to significantly ameliorate poor nutrition and food insecurity in sub-Sahara Africa if problem of poor seed...  相似文献   
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