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991.
目的 :比较不同文化背景的精神专科医生在评估多动症儿童各种症状表现时的一致程度 ,探讨文化对儿童多动症诊断可能产生的影响。方法 :使用单独或集体行为观察清单 ,让两地的精神科医生对儿童多动症的各种表现进行症状评估 ;所有的评估者均观察同一录像带上患儿的行为表现 ;对其评定结果进行统计和比较。结果 :儿童独自活动观察量表的 12项中有 11项症状条目评定结果类似 ,有 3项英国医生的评分高于中国医生 ,有 9项中国医生评分高于英国医生 ,其中 1项具有显著性差异。结论 :对行为表现和症状认知的文化差异可能使流行病学的研究出现不同的结果 ,即使使用统一的诊断标准和症状评分量表作为诊断工具 ,不同文化背景的国家 ,儿童多动症的患病率仍然可不一致  相似文献   
992.
The process of luteinization, during which granulosa cells are transformed into luteal cells, is accompanied by dramatic changes in the response of luteal cells to LH. Although luteal cells require LH-cAMP signalling cascade for survival, whether these cells respond to trophic factors through changes in gene expression remains poorly characterized. In an attempt to characterize gonadotrophin (LH)-regulated gene expression in the bonnet monkey corpus luteum (CL), changes in gene expression after GnRH antagonist treatment to inhibit LH secretion, different stages of CL and during hCG-simulated early pregnancy were examined using differential display RT-PCR, Northern blot and semiquantitative RT-PCR analyses. We have identified seven non-redundant cDNA's whose expression were regulated by LH. The results show that inhibition of LH secretion not only leads to down-regulation in the expression of genes, e.g. low density lipoprotein (LDL) receptor and Aldose reductase, but expression of some of the genes was up-regulated, e.g. Humanin, RNA helicase, Lyric protein, Acidic ribosomal phosphoprotein and KIAA1750. mRNA levels of the genes identified as up-regulated after LH inhibition were higher during late compared to the early and mid-luteal phase CL, but treatment with hCG down-regulated their expressions. We conclude that we have identified novel genes (known and unknown) that are up or down-regulated by LH, and the results suggest that LH-mediated activation and repression of expression of many genes is central to the regulation of the structure and function of the CL in the monkey.  相似文献   
993.
994.
Thirty-eight patients of NIDDM, 12 of IDDM and 10 healthy age matched controls were subjected to seven standardised autonomic reflex function tests. A scoring criteria was utilised for diagnosing and grading the severity of dysautonomia. Eight patients of IDDM and 24 of NIDDM had dysautonomia. One-third of the patients in each group had grade IV autonomic dysfunction. Severity of autonomic dysfunction was directly related to the duration of disease in NIDDM whereas in IDDM this relation was not seen. Peripheral neuropathy was almost always associated with dysautonomia in NIDDM. On the contrary, in IDDM dysautonomia was independent of peripheral neuropathy. Charcot's arthopathy, dysphagia, constipation and nocturnal diarrhea were always associated with evidence of dysautonomia. Other symptoms viz. gustatory sweating, postural dizziness and impotence did not necessarily indicate dysautonomia.  相似文献   
995.
Uveitis is an inflammation of the uveal tract and is one of the major causes of visual impairment. Several lines of evidence suggest an important role for activated T lymphocytes in the perpetuation of posterior uveitis. In sequel to our preliminary observations with human S-antigen, we have further investigated the proliferative response of peripheral blood lymphocytes of posterior uveitis patients against 20 linear and 9 overlapping peptides of retinal S-antigen. The expression of surface markers CD4, CD8, CD29, CD45RA in peripheral blood was detected by flow cytometry. We have also assessed the pattern of cytokines present in peripheral blood mononuclear cells (PBMCs) using ribonuclease protection assay (RPA). Nineteen out of 32 patients' lymphocytes showed proliferative response to S-antigen, one or more of its 20 linear and nine overlapping synthetic peptides. Six patients showed significant lymphoproliferative response against various peptides. The maximum response was found to peptides from the 231-270 amino acid region of human S-antigen sequence. The percentage of CD29(+) (memory cells) and CD45RA(+) (naive cells) T-lymphocytes was higher in patients compared to healthy volunteers. There was a demonstrable difference in the percentage of CD4(+) and CD8(+) lymphocytes in the patients (P <== 0.05) as compared to controls. Higher message for interleukin (IL)-5, IL-10, IL-15, IL-9, IL-2, IL-13, and interferon (IFN)-gamma was observed in uveitis patients than in healthy individuals. In brief, our study suggests that a particular region of S-antigen plays an important role in idiopathic uveitis.  相似文献   
996.
Conserved and variant regions of two blood stage vaccine candidate antigens of Plasmodium falciparum, merozoite surface antigen (MSA-1) and ring-infected erythrocyte surface antigen (Pf155/RESA), have been shown to be immunogenic. However, the relative immunogenicity of these immunogens in different populations has not been studied. The conserved N-terminal region of MSA-1 was investigated for its immunogenicity by studying cellular (T cell) and humoral (B cell) immune responses in P. falciparum-primed individuals, living in malaria-hyperendemic areas (Orissa State, India), where malaria presents an alarming situation. MSA-1-derived synthetic peptides contained sequences that activated T cells to proliferate and release gamma interferon in vitro. There was considerable variation in the responses to different peptides. However, the highest responses (51% [18 of 35] by proliferation and 34% [12 of 35] by gamma interferon release) were obtained with a synthetic hybrid peptide containing sequences from conserved N- and C-terminal repeat regions of MSA-1 and Pf155/RESA, respectively. Antibody reactivities in an enzyme immunoassay of plasma samples from these donors to different peptides used for T-cell activation were heterogeneous. In general, there was poor correlation between DNA synthesis and either gamma interferon release or antibody responses in individual donors, underlining the importance of examining several parameters of T-cell activation to assess the total T-cell responsiveness of a study population to a given antigen. However, the results from our studies suggest that synthetic constructs containing sequences from the N- and C-terminal regions of MSA-1 and Pf155/RESA representing different erythrocytic stages of the P. falciparum parasite are more immunogenic in humans living in malaria-hyperendemic areas of India who have been primed by natural infection.  相似文献   
997.
M. Yadav 《Immunology》1971,21(5):839-851
The transmission of antibodies across the gut of suckling pouch-young was investigated in three species of marsupials (Setonix brachyurus, Macropus eugenii and Trichosurus vulpecula) from Australia.

Mother Setonix, immunized against Salmonella adelaide flagella and Bacteriophage Φ × 174, transmitted the antibodies in milk to their young. In sucrose density gradient runs, the antibody activity in milk whey and in serum of pouch-young, of Setonix and Macropus was found to be in the 7S region only; antibody in the 11S and 19S regions was not detected. Chromatographic preparations of IgM antibodies were fed to pouch-young Setonix which were later bled and their serum titrated for anti-S. adelaide agglutinins and antiphage Φ × 174 activity. The IgM antibodies were not transmitted across the gut in detectable amounts.

Antibodies were present in the blood of pouch-young Setonix within 15–60 minutes of gavage (feeding by stomach tube) of immune serum. In Setonix the capacity to absorb antibodies in the intestine was lost at an age between 170 and 200 days and in Trichosurus it was lost at an age between 98 and 145 days. At these ages the pouch-young were able to leave the marsupium for varying lengths of time. Antibodies did not traverse the rumen wall in a young Setonix whose rumen was isolated from the intestine with ligatures before immune serum was gavaged.

  相似文献   
998.
ABSTRACT

Infectious laryngotracheitis (ILT) is a highly contagious respiratory disease of chickens, pheasants, and peafowl. It is caused by the alpha herpesvirus, infectious laryngotracheitis virus (ILTV). Glycoprotein D (gD) of ILTV is immunogenic and helps in its binding to the susceptible host cell receptor. In the present study, a recombinant gD protein was expressed in a prokaryotic system to develop a single serum dilution ELISA. In addition, two immunogenic peptides, corresponding to regions 77–89 and 317–328, were identified in gD protein. The peptides were synthesized using solid-phase peptide synthesis, purified using reversed-phase HPLC, and characterized using mass spectrometry. The peptides displayed a good titre and were found to be promising antigens to coat the ELISA plate to detect the ILTV antibodies in the serum sample. The developed ELISA showed 96.9% sensitivity, 87.5% specificity, and 95.3% accuracy as compared to OIE referenced standard indirect ILTV ELISA (whole viral coated). The assay may not differentiate vaccinated from infected birds when the flocks are administered with live attenuated vaccines. However, the assay could be useful to detect the disease condition in birds vaccinated with recombinant vaccine expressing glycoproteins other than gD. The developed ILTV single serum dilution ELISA could be an alternative to the existing diagnostics for the detection of ILTV antibodies.  相似文献   
999.
In an area of India where the main rural malaria vector, Anopheles culicifacies Giles, has developed triple resistance to DDT, HCH, and malathion sprayed indoors in antimalaria program, bifenthrin (10% wettable powder) was evaluated in a randomized house-scale trial between July 1999 and March 2000. Entomological impact of four serial doses of bifenthrin (25, 50, 100, and 200 mg/m2) sprayed in rooms in five villages was compared with malathion (2 g/m2) and unsprayed control. An. culicifacies was 100% susceptible to bifenthrin (0.1%), but only 57% to malathion (5%) test papers. Contact bioassays were carried out on sprayed surfaces for 24 wk, and 24 h mortality in An. culicifacies was recorded. Bifenthrin 100- and 200-mg doses caused > or = 80% mortality until 24 wk. The 50-mg dose caused > or = 80% mortality on tin, wood, and mud surfaces for 24 wk, and on brick walls for 16 wk. Bifenthrin 25-mg dose produced > or = 80% mortality for 24 wk on tin, 20 wk on mud walls, 16 wk on brick walls, and 8 wk on wood surfaces. Persistence of > or = 80% mortality did not differ for 25- and 50-mg doses on any surface except on wood (P < 0.05). Malathion sprayed in three rounds of 6 wk apart caused > or = 80% mortality for 16 wk on the brick and mud walls, and for 20 wk on the tin and wood surfaces. Bifenthrin 25- and 50-mg doses produced a similar impact on the densities of An. culicifacies and other mosquitoes but a superior one to malathion or control. Bifenthrin 25-mg dose caused least excitorepellency. Overall, efficacy of bifenthrin was superior to malathion. Considering the duration of the persistence of significant insecticidal action of bifenthrin on the most common surfaces (mud and brick walls), least excito-repellency and a relative impact on the mosquito densities, the 25-mg dose was the most superior among all the four doses evaluated.  相似文献   
1000.
Hemoglobin mediated cytotoxicity and apoptosis has been evaluated in Tumor necrosis factor-alpha (TNF-alpha) sensitive cell line, U937 and compared with TNF-alpha. Both species of hemoglobin, Hemoglobin A2 and Hemoglobin A0 induced apoptosis and cytotoxicity in U937 cell as measured by flow cytometry and 3-(4,5-dihydro-6-(4-(3,4-dimethoxybenzooyl)-1-piperazinyl)-2(1H)-quinoline (MTT) assay respectively. Different concentration of Hemoglobin A0 (4 ng/mL to 4000 ng/mL) induced apoptosis ranging from 9% to 16% in U937 cells. 4000 ng/mL hemoglobin A0 showed maximal apoptotic cells. TNF-alpha showed 87% apoptotic U937 cells at concentration of 1 pg/mL. HbA0 displayed cytotoxicity in U937 cell line at higher concentration in comparison to TNF-alpha. 4000 ng/mL of hemoglobin A0 showed optimal cytotoxic response in U937 cells. A dose response curve was also observed with varying doses of hemoglobin A0. U937 cells pretreated with serum activated LPS for 1 hr and incubated with different concentration of hemoglobin or human TNF-alpha for 24 h reduced the cytotoxic effect on U937. Dexamethasone treatment of U937 cells helped in protecting the HbA0 and HbA2 mediated cytotoxicity and anti-TNF-alpha antibody neutralized the hemoglobin mediated apoptosis and cytotoxicity. It is therefore apparent that human hemoglobin shares some of the bioactivities previously ascribed to TNF-alpha. Sharing of bioactivities of TNF-alpha by hemoglobin is interesting and suggests that cell free hemoglobin can mimic TNF-alpha functionally.  相似文献   
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