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21.
Intestinal schistosomiasis japonica: CT-pathologic correlation 总被引:1,自引:0,他引:1
Lee RC; Chiang JH; Chou YH; Rubesin SE; Wu HP; Jeng WC; Hsu CC; Tiu CM; Chang T 《Radiology》1994,193(2):539
22.
B Betschart H P Rieder K Gautschi D de Savigny A A Degrémont M Tanner 《Acta tropica》1987,44(2):191-211
Total protein concentration, zinc, prealbumin, albumin, alpha-1-, alpha-2-, beta- and gammaglobulin concentrations were measured in serum samples collected in three successive years (1982, 1983 and 1984) from children (1 month-15 years) of Kikwawila village, Tanzania. The analysis of a total of 1590 serum samples provided the baseline data for children living in a rural Tanzanian community. The total protein values and the concentrations of betaglobulin were within the range described for Caucasians. Albumin, prealbumin, alpha-1- and alpha-2-globulin concentrations were below these standard values. On the other hand the gammaglobulin concentration was twice as high. The concentrations of total protein, gammaglobulin and prealbumin correlated with age. From 1982 to 1983 a significant decrease of most of the serum components (incl. zinc) was observed, although in children older than 2 years the alpha-1-globulins increased. All values increased again from 1983 to 1984, except for the zinc concentration, which decreased further. The individual fluctuations were analysed by comparing paired values for the children participating in the period 1982-1983, or 1983-1984. The proportion of children showing large fluctuations, sometimes exceeding the selected limits of tolerance, was larger in the period 1982-1983 than 1983-1984. This was consistent with the overall pattern found for all children. The prealbumin level, which has been postulated to be an indicator for malnutrition or borderline malnutrition, was analysed in detail. The values were far below normal values (200-300 mg/l), reaching a plateau with 130 mg/l among 4-6-year-old children. The individual fluctuations indicated a decrease from 1982 to 1983, which was considerable both in terms of the proportion of children showing a decrease (55%) and in the magnitude of the decrease. There was an increase from 1983 to 1984 but this increase did not compensate for the loss in 1983. Prealbumin concentrations showed a slight trend towards decreased values with stunting and wasting. No direct correlation was found between the other biochemical parameters and the parasite or anthropometric data collected at the same time. It was difficult to establish direct relationships between the biochemical parameters, which mainly indicate the health status of the child at the time-point of the survey, and anthropometric parameters which reflect the history of the individual over a long period. No direct correlation could be established between the biochemical parameters and the parasitological data.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
23.
Lesley Barclay RN CM BA MEd Louise Everitt RN CM Post Grad Dip-Comm Health Frances Rogan RN CM B App S M Com Nurs Virginia Schmied RN CM BA MA Hons Aileen Wyllie RN CM BA MHPEd 《Journal of advanced nursing》1997,25(4):719-728
This paper presents the results of a qualitative study conducted by midwife researchers into women's experience of new motherhood. Data were collected using focus groups involving 55 first-time mothers and analysed using grounded theory method. The analysis produced six categories: 'realizing', 'unready', 'drained', 'aloneness', 'loss' and 'working it out'. The core category, 'becoming a mother', integrates all other categories and encapsulates the process of change experienced by women. Also explained are factors mediating the often distressing experience of becoming a mother. The analysis provides a conceptualization of early motherhood enabling the development of strategies for midwives, nurses and others helping women negotiate this challenge. 相似文献
24.
Summary— Experiments were designed to determine whether or not indapamide, an antihypertensive agent with vasodilator properties, inhibits endothelium-dependent contractions. Rings of aortae with and without endothelium from spontaneously hypertensive rats (SHR) were suspended in conventional organ chambers for the measurement of isometric force. Acetylcholine and adenosine diphosphate-β-S in the presence of a nitric oxide synthase inhibitor, caused endothelium-dependent contractions, which were inhibited by indapamide. The compound (10−4 M) also slightly reduced the contractions of rings without endothelium evoked by U-46,619, which activates thromboxane-endoperoxide receptors. These results demonstrate that indapamide inhibits endothelium-dependent contractions in the SHR aorta, and suggest that the inhibition is due, at least in part, to the action of the drug on the hypertensive vascular smooth muscle. 相似文献
25.
Summary Development of third-stage larvae ofDipetalonema viteae within subcutaneously implanted micropore chambers proceeded in all hosts tested up to the fourth-stage larvae and occasionally to adolescent worms. In the jird the timing of development was comparable to a natural infection. Although the mouse is an insusceptible host, larval development could take place, but was very slow. Two intraperitoneal inoculations of living thirdstage larvae into mice induced the production of antibodies against the larval cuticle and against common antigens. In such immune mice the development of third- and fourth-stage larvae within micropore chambers was significantly inhibited, larval mortality was increased, and the larval motility was impaired. 相似文献
26.
Targeted gene disruption of murine CD7 总被引:2,自引:0,他引:2
CD7 is a 40 kDa type I transmembrane glycoprotein member of the Ig
superfamily. CD7 is a marker of mature human T cells and NK cells, and is
expressed early in their development. Cross-linking CD7 positively
modulates T cell and NK cell activity as measured by calcium fluxes,
expression of adhesion molecules, cytokine secretion and proliferation. CD7
associates directly with phosphoinositol 3'-kinase, and CD7 ligation
induces production of D-3 phosphoinositides and tyrosine phosphorylation.
Severe combined immunodeficiency has been associated with a lack of
lymphocyte surface CD7. The CD7 ligand is unknown. The murine CD7 homolog
is encoded by a single gene on chromosome 11. In order to characterize the
role of CD7 in lymphocyte development and function we have eliminated the
CD7 gene by targeted disruption. CD7- deficient mice display normal
histology of thymus and spleen, normal lymphocyte populations in primary
and secondary lymphoid tissues, and normal serum Ig levels. Specific
antibody responses after immunization with T-dependent and T-independent
antigens are equivalent in wild-type and CD7 knockout mice. CD7-deficient
lymphocytes respond normally to T cell mitogenic and allogeneic stimuli,
and display normal NK cell cytotoxicity.
相似文献
27.
28.
The effects of antioxidant supplementation during Percoll preparation on human sperm DNA integrity 总被引:20,自引:6,他引:20
Hughes CM; Lewis SE; McKelvey-Martin VJ; Thompson W 《Human reproduction (Oxford, England)》1998,13(5):1240-1247
The integrity of sperm DNA is crucial for the maintenance of genetic
health. A major source of damage is reactive oxygen species (ROS)
generation; therefore, antioxidants may afford protection to sperm DNA. The
objectives of the study were, first, to measure the effects of antioxidant
supplementation in vitro on endogenous DNA damage in spermatozoa using the
single cell gel electrophoresis (comet) assay and, second, to assess the
effect of antioxidant supplementation given prior to X-ray irradiation on
induced DNA damage. Spermatozoa from 150 patients were prepared by Percoll
centrifugation in the presence of ascorbic acid (300, 600 microM), alpha
tocopherol (30, 60 microM), urate (200, 400 microM), or acetyl cysteine (5,
10 microM). DNA damage was induced by 30 Gy X-irradiation. DNA strand
breakage was measured using the comet assay. Sperm DNA was protected from
DNA damage by ascorbic acid (600 microM), alpha tocopherol (30 and 60
microM) and urate (400 microM). These antioxidants provided protection from
subsequent DNA damage by X-ray irradiation. In contrast, acetyl cysteine or
ascorbate and alpha tocopherol together induced further DNA damage.
Supplementation in vitro with the antioxidants ascorbate, urate and alpha
tocopherol separately has beneficial effects for sperm DNA integrity.
相似文献
29.
Cellular fatty acid composition of Actinobacillus actinomycetemcomitans and Haemophilus aphrophilus. 总被引:3,自引:3,他引:3 下载免费PDF全文
S D Braunthal S C Holt A C Tanner S S Socransky 《Journal of clinical microbiology》1980,11(6):625-630
Strains of Actinobacillus actinomycetemcomitans isolated from deep pockets of patients with juvenile periodontitis were analyzed for their content of cellular fatty acids. Oral Haemophilus strains, morphologically and biochemically similar to Haemophilus aphrophilus, were also examined for their content of cellular fatty acids. The extractable lipids of the actinobacilli represented approximately 10% of the cell dry weight, with the bound lipids representing 2 to 5%. The major fatty acids consisted of myristic (C14:0) and palmitic (C16:0) acids and a C16:1 acid, possibly palmitoleic acid, accounting for 21, 35, and 31% of the total extractable fatty acids, respectively. Haemophilus strains had a similar cellular fatty acid content. 相似文献
30.
Optimization of plasmid maintenance in the attenuated live vector vaccine strain Salmonella typhi CVD 908-htrA 总被引:4,自引:0,他引:4 下载免费PDF全文
Galen JE Nair J Wang JY Wasserman SS Tanner MK Sztein MB Levine MM 《Infection and immunity》1999,67(12):6424-6433
The broad objective of the research presented here is to develop a noncatalytic plasmid maintenance system for the stabilization of multicopy expression plasmids encoding foreign antigens in a Salmonella typhi live-vector vaccine strain such as CVD 908-htrA. We have enhanced the maintenance of expression plasmids at two independent levels. First, we removed dependence upon balanced-lethal maintenance systems that involve catalytic enzymes expressed from multicopy plasmids; we accomplished this through incorporation into expression plasmids of a postsegregational killing system based on the noncatalytic hok-sok plasmid addiction system from the antibiotic resistance factor pR1. We also included at least one naturally occurring plasmid partition function in our expression plasmids, which eliminates random segregation of these plasmids, thereby enhancing their inheritance and stability; to accomplish this, we incorporated either the par locus from pSC101, the parA locus from pR1, or both. We monitored the stability of optimized expression plasmids within CVD 908-htrA by quantitating expression of a variant of green fluorescent protein (GFPuv) by using flow cytometry. In this report, we demonstrate the utility of this novel plasmid maintenance system in enhancing the stability of our expression plasmids and go on to show that as the copy number of stabilized plasmids increases, the toxicity of GFPuv synthesis also increases. The implications of these observations for the rational design of immunogenic and protective bacterial live vector vaccines are discussed. 相似文献