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91.
92.
The regions of sequence variation in caulimovirus gene VI   总被引:1,自引:0,他引:1  
M Sanger  S Daubert  R M Goodman 《Virology》1991,182(2):830-834
The sequence of gene VI from figwort mosaic virus (FMV) clone x4 was determined and compared with that previously published for FMV clone DxS. Both clones originated from the same virus isolation, but the virus used to clone DxS was propagated extensively in a host of a different family prior to cloning whereas that used to clone x4 was not. Differences in the amino acid sequence inferred from the DNA sequences occurred in two clusters. An N-terminal conserved region preceded two regions of variation separated by a central conserved region. Variation in cauliflower mosaic virus (CaMV) gene VI sequences, all of which were derived from virus isolates from hosts from one host family, was similar to that seen in the FMV comparison, though the extent of variation was less. Alignment of gene VI domains from FMV and CaMV revealed regions of amino acid sequence identical in both viruses within the conserved regions. The similarity in the pattern of conserved and variable domains of these two viruses suggests common host-interactive functions in caulimovirus gene VI homologues, and possibly an analogy between caulimoviruses and certain animal viruses in the influence of the host on sequence variability of viral genes.  相似文献   
93.
1. A pulmonary chemodectoma/glomangiosarcoma that had metastasized from the thigh was studied after removal from a 22 year old Algerian patient with hypertension, high plasma prorenin and signs of secondary aldosteronism. 2. Renin and renin mRNA were localized in sections of the tumour tissue using monoclonal anti-human renin antibody and human renin cDNA probe, respectively. 3. The cells grew prolifically in culture, but, even though their renin content was similar to that of transfected human juxtaglomerular cell tumour cells (approximately 1 pg/microgram DNA), their rate of secretion of renin was much lower (0.05-0.15 cf. 0.5-1.5 pg/h per microgram DNA). 4. Forskolin (10 mumol/l for 24 h) increased secretion of renin from 1.9 +/- 0.36 to 4.1 +/- 0.64 pg/ml per h of culture (P less than 0.001, n = 11), consistent with cAMP being a second messenger in the secretory mechanism. 5. The cells should provide valuable information about intracellular mechanisms for the regulation of renin synthesis and secretion.  相似文献   
94.
Parotid saliva contains a variety of proline-rich proteins. This study found that, among 306 children between the ages of 5 to 15 years, there is a significant increase in the decayed-missing-filled tooth surface (DMFS) score of the permanent teeth with age in children with the specific proline-rich protein phenotypes Pa and Pr. However, the increase in DMFS score of the permanent teeth of children was significantly greater in children with Pa+ and Pr22 than in those with the other phenotypes (Pa- or Pr11 and Pr12). The previously established close correlation between the Pa and Pr phenotypes and the genetic variants of salivary peroxidase (a powerful antibacterial system in the oral cavity) may provide an explanation for the relationship of certain proline-rich protein phenotypes to dental caries.  相似文献   
95.
Summary After orthotopic rat liver transplantation in the fully allogeneic BN (RT-1n) to LEW (RT-11) combination, the phenomenon of spontaneous tolerance of donor antigen occurs. We demonstrate two different immune mechanisms that may account for this process. Using adoptive transfer assays we show the presence of donor-specific T-suppressor lymphocytes in the spleens of long-term surviving liver graft, recipients. These cells prolong - adoptively transferred into irradiated syngeneic hosts — the survival of donor-specific (BN) but not third-party (DA) renal allografts (I00 days vs 1I days in control groups). Secondly, we demonstrate the replacement of Kupffer cells in the graft by recipient macrophages using polymorphic monoclonal antibodies in an immunoperoxidase technique. This may contribute to graft adaptation and thus to long-term graft acceptance.  相似文献   
96.
Ketanserin, a recently developed 5-HT2 receptor antagonist, competitively and selectively blocks the vasoconstrictor activity of 5-hydroxytryptamine (serotonin). We explored a possible contribution of serotonin to augmented vascular tone in patients with severe heart failure, using intravenous and oral formulations of ketanserin. When administered intravenously (10 mg bolus, 4 mg/hr infusion for +/- 40 min) to 10 patients with congestive heart failure (NYHA III or IV) secondary to congestive cardiomyopathy (n = 8) or ischemic heart disease (n = 2), the drug produced a significant increase in cardiac output (rest 24%, p less than 0.001; exercise 19%, p less than 0.01) which was accompanied by a fall in systemic arterial pressure (rest 7%, p less than 0.001; exercise 10%, p less than 0.05) and pulmonary wedge (rest 17%, p less than 0.05; exercise 23%, p less than 0.001) pressure. Calculated systemic vascular resistance (SVR, rest 27%, p less than 0.001; exercise 23%, p less than 0.05) decreased significantly. No significant hemodynamic changes were observed when 40 mg of ketanserin was administered orally to the same group of patients. Plasma catecholamines (norepinephrine, NEP:epinephrine, EP:dopamine) were measured before and after ketanserin at rest and during exercise. Baseline NEP levels were markedly elevated at rest and during exercise in all patients (rest: 878 +/- 381 ng/mL, exercise: 1453 +/- 697 ng/mL). Baseline EP levels were within normal limits. Ketanserin did not produce any change in catecholamine concentration.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
97.
Habitat characteristics were examined in two marshes and the littoral zones of two lakes in central Florida to determine their effect on the density and distribution of Coquillettidia perturbans. Larval and water samples were collected and habitat characteristics were recorded at monthly intervals for one year. Several significantly different physicochemical parameters were found between the marshes and lakeshores. Sites with dissolved oxygen less than 1.5 mg/liter (from October through May), pH less than 5.2, total alkalinity less than 6.0 mg CaCO3/liter, and orthophosphate less than 0.25 mg/liter were associated with significantly higher concentrations of Cq. perturbans. Arrow-arum, caric sedge, and maidencane were also associated with higher numbers of Coquillettidia.  相似文献   
98.
The effect of meals on the physiological and physicochemical actions of potassium citrate was examined in 8 patients with nephrolithiasis maintained on a constant metabolic dietary regimen. Potassium citrate (20 mEq. 3 times per day), whether given with food or on an empty stomach, significantly increased urinary pH, citrate and potassium, and decreased urinary calcium and ammonium. Moreover, potassium citrate decreased urinary saturation of calcium oxalate and uric acid, although it slightly increased that of brushite. However, there was no significant difference in these measures when the drug was given with meals from the time when it was given on an empty stomach. Thus, the effect of potassium citrate on urinary risk factors is unaffected by food.  相似文献   
99.
Alzheimer's disease can be accurately diagnosed by clinical methods alone in about 90% of cases. The adoption of uniform diagnostic criteria and assessment procedures, such as those developed by the Consortium to Establish a Registry for Alzheimer's Disease (CERAD), will likely improve the characterization of the disease across a variety of clinical settings. In general, Alzheimer's disease is a relentlessly progressive disorder; however, it also is clinically heterogeneous. This is underscored by its diverse cognitive deficits, neurologic features, behavioral pathology, and rates of progression.  相似文献   
100.
Velo-cardio-facial syndrome (VCFS) is associated with deletions on the long arm of chromosome 22, mild intellectual disability, poor social interaction and a high prevalence of psychosis. However, to date there have been no studies investigating the neuropsychological functioning of adults with VCFS. We compared 19 adults with VCFS with 19 age, gender and IQ matched controls using a comprehensive neuropsychological battery. Compared to controls, adults with VCFS had significant impairments in visuoperceptual ability (Visual Object and Space Perception Battery), problem solving and planning (Tower of London) and abstract and social thinking (Comprehension WAIS-R). It is likely that haploinsufficiency (reduced gene dosage) of a neurodevelopmental gene or genes mapping to chromosome 22q11 underlies the cognitive deficits observed in individuals with VCFS.  相似文献   
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