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At least 955 records · Page 53Linked to original sources
PubMed1998

[Hepatic focal lesions: role of color Doppler ultrasonography with contrast media].

INTRODUCTION: The differential diagnosis of focal hepatic lesions is still studied by diagnostic imaging operators. A big step forward in the field of ultrasound (US) has come from the color Doppler mode permitting accurate studies of the vascularization of focal hepatic lesions. Echocontrast agents have further improved color Doppler sensitivity to slow flows and have permitted to visualize intralesional vascular signals which were missed at B-mode US. New data have thus been acquired which can be integrated with flowmetric findings to help make the correct differential diagnosis with a fair safety margin. We studied the pathognomonic US pattern for each type of lesion. MATERIAL AND METHODS: We examined 55 patients with single hepatic lesions which had already been typified: they were 10 hepatic angiomas, 3 focal nodular hyperplasias (FNH), 2 hepatic adenomas, 20 hepatocarcinomas and 20 hepatic metastases. Color Doppler investigations were performed on each patient before and after the intravenous (i.v.) administration of an echocontrast agent (Levovist, Schering AG, Berlin, Germany). For each lesion we studied the morphological characteristics, the resistance index (RI) of intralesional arterial vessels, the hepatic perfusion index and the maximum speed in intralesional vessels. RESULTS: Contrast-enhanced US showed no intralesional signals or afferent branches in 8 hepatic angiomas, which however exhibited some peripheral vascularization; weak intralesional vascular signals were demonstrated in 2 cavernous angiomas. Intralesional signals, as well as peripheral vascularization, were detected in the 3 FNH cases, which also exhibited a centripetal afferent branch; the hepatic perfusion index in these lesions never exceeded .25. The two hepatic adenomas had similar color flowmetry to FNH also after i.v. contrast agent administration, except for the contripetal afferent vessel which was not seen. In the 20 hepatocarcinomas, contrast-enhanced images showed numerous intralesional signals and afferent branches which, with the peripheral vascularization, resulted in a basket-like pattern. Flowmetry of intralesional arterial vessels showed an irregular systodiastolic range, with RI = .32 +/- .5 in 12 lesions and high in the remaining 8 lesions (RI = .82 +/- 10). The hepatic perfusion index was .65 +/- 10 in all patients. In 14 of the 20 hepatic metastases, B-mode US showed no intralesional signals except for 6 metastases from colorectal carcinoma, and contrast-enhanced findings were about the same. The hepatic perfusion index at flowmetry ranged .30 to .45 in all patients.

Adult↗
PubMed1989

Where are all the health care workers?

From the Panhandle to the Rio Grande Valley, the Gulf Coast to Big Bend, major health care systems to rural hospitals, the story is the same: There aren't enough qualified health care workers to go around, and the problem is getting worse.

Allied Health Personnel↗
PubMed1993

[Which women experience divorce?].

"This study reports on the determinants of divorce of married Dutch women, born between 1950 and 1969.... The impact of several factors on the divorce process is examined.... The analyses show that the women who have the highest divorce rates grew up in a big city, cohabited before marriage (and are or were religious), married before age 21 in the period 1980-88 and had a child before, or within six months after, the wedding. On the basis of these results, it is estimated that 20% will experience divorce within the first five years of their marriage. The data for the analyses have been derived from The Netherlands Fertility Survey (1988)...." (SUMMARY IN ENG)

Cohort Studies↗
PubMed2005

[Smoking and passive smoking in Chinese, 2002].

OBJECTIVE: To describe the prevalence of smoking, quitting smoke, and passive smoking in different populations by education status, occupation and geographic distribution. METHODS: Surveillance on risk behaviors in 145 disease surveillance points (DSP) was carried out in 2002 by multi-steps random sampling through questionnaires. 16,407 records had been completed with 16 056 used for analysis. Indicators as smoking, current smoking, average cigarettes smoked and the cost per day, etc., were calculated by weight on age proportions from the 2000 census. RESULTS: Ever-smoking rates in males and females aged 15 and over were 66.0% and 3.1%, respectively with ever-smoking rate dropped 1.8% in whole population, but increased in people aged 15-24. The number of total smokers was about 350 million, 30 million more than that in 1996. There were no obvious geographic differences seen among male, but big difference was seen in female smokers. Higher smoking rates were seen in the northeast and northern parts of the country. Rate of quitting smoking was increasing, from 9.42% in 1996 to 11.5% in 2002, referring to an increase of 10 million quitters. However, the rate of no intention to quit among smokers was still very high--74%. The average cigarettes consumption per person-day was the same as that in 1996--14.8 cigarettes/day, which cost 2.73 RBM/day. The cost was various in different groups of population with a 15 times difference. The level of exposure for passive smokers was not improved. The prevalence of passive smoking in nonsmokers were 53% in 1996 and 52% in 2002. Knowledge on smoking and health condition in population had been greatly improved, but still poor in the western areas. 60% of the people claimed in supporting banning of smoking in public places, 45% supporting the banning of all cigarettes ads, but big difference was seen in different geographic areas. CONCLUSION: The prevalence of smoking in Chinese males had reached its peak, leveling but had not yet obvious dropped. Communication on the knowledge of harm in smoking remained weak since people did not understand or support the strategies on tobacco control, especially in the western areas. Data indicated that the prevalence of tobacco use would not decrease over in short period and the disease burden caused by tobacco use would still be heavy in the next 30-50 years. The government and public health authorities should develop effective tobacco control in no time to decrease disease burden caused by smoking and passive smoking.

Adolescent↗
PubMed2005

[Phylogenetic analysis for H3A1 strain of all human influenza A virus].

OBJECTIVE: Influenza A virus remains an important pathogen which threatens humans. With the help of latest developed bioinformatics tools, all available human Influenza A virus H3A1 strains were explored to deeply understanding its evolution and variation rules. METHODS: All data of H3A1 sequence in NCBI Genbank and Influenza sequence database were downloaded and aligned in ClustalX with two step cluster method used to split the data and Bayesian phylogenetic tree analysis method applied to precisely construct phylogenetic tree for each clusters. RESULTS: Tree topology indicated that H3 strains evolved along a single evolution trunk and tree pattern and model parameter showed obvious variety tendency with time period. However, no geographic distribution features were found for key variation strains and big branch in trees. CONCLUSION: The evolution of human H3 strains were mainly driven by the interaction of human immune barriers and antigenic drift of virus. Since the influenza subtype had already been spread in human population, south China should not be considered as the originated areas of new strains, hence it should be treated as equally as other places in the world.

Antigens↗
PubMed1993

Structural description of agrammatic comprehension.

The trace-deletion hypothesis (Grodzinsky, 1990) holds that the comprehension deficit apparent in most agrammatic aphasics results from the absence of traces at the level of S-structure. This paper reports a test of this hypothesis in a case study of an agrammatic aphasic. Two experiments--one using a sentence-picture matching task, one using the truth-value judgment task-examined the comprehension of the matrix clause in center-embedded relatives such as, The tiger that chased the lion is big. These structures provide a crucial test of the trace-deletion hypothesis because comprehension of the matrix clause (i.e., knowing that the tiger is big and not the lion) is predicted to be unimpaired. Contrary to this prediction, however, the results of the present work show that comprehension of the matrix clause in such sentences is significantly impaired. We argue that a revised version of the trace-deletion hypothesis proposed by Hickok (1992a,b) can explain the present data and other previously unaccountable findings.

Aged↗
PubMed2006

Comparison of computing capability and information system abilities of state hospitals owned by Ministry of Labor and Social Security and Ministry of Health.

The main purpose of this study is to give an idea to the readers about how big and important the computing and information problems that hospital managers as well as policy makers will face with after collecting the Ministry of Labor and Social Security (MoLSS) and Ministry of Health (MoH) hospitals under single structure in Turkey by comparing the current level of computing capability of hospitals owned by two ministries. The data used in this study were obtained from 729 hospitals that belong to both ministries by using a data collection tool. The results indicate that there have been considerable differences among the hospitals owned by the two ministries in terms of human resources and information systems. The hospital managers and decision makers making their decisions based on the data produced by current hospital information system (HIS) would more likely face very important difficulties after merging MoH and MoLSS hospitals in Turkey. It is also possible to claim that the level and adequacy of computing abilities and devices do not allow the managers of public hospitals to use computer technology effectively in their information management practices. Lack of technical information, undeveloped information culture, inappropriate management styles, and being inexperienced are the main reasons of why HIS does not run properly and effectively in Turkish hospitals.

Government Agencies↗
PubMed1992

Clams as pollution bioindicators in Kuwait's marine environment: metal accumulation and depuration.

This study has developed and verified clam transplantation for marine pollution monitoring in Kuwait and has assessed its reliability for monitoring pollution by heavy metals through laboratory and field transplantation experiments. In field experiments, live specimens of the clam Circenita callipyga were transplanted, either suspended in seawater or buried in sand, to 11 coastal sites in Kuwait; subsamples of transplanted clams were recovered at intervals over a 6-month period. In laboratory experiments, heavy metal accumulation for 36 days and depuration (body's release of pollutants) for 60 days in small and big clams were investigated. Clams subsampled in laboratory and field experiments were analyzed for Hg, Cu, V, Cd and Pb. Results showed the ability of clams to survive under the transplantation conditions. Accumulation of biofouling materials was a problem at only two transplantation sites and was overcome by periodic cleaning. Statistical analysis of laboratory experimental data showed significant accumulation of all test metals and significant depuration of Hg, Cu, V and Cd. Rates of metal accumulation and depuration differed in relation to clam size class. Field experiments indicated statistically significant increases in Hg and Cu concentrations in the transplanted clams at most stations, no change in Cd concentrations and an increase or, occasionally, a decrease in V and Pb concentrations.

Analysis of Variance↗
PubMed1978

Sensitivity and accuracy of the visual analogue scale: a psycho-physical classroom experiment.

1 Twenty-seven intelligent volunteers took part in a classroom experiment on two occasions to assess subjectively, ordinally related volumes of sound (offered in random sequence), using the visual analogue scale. 2 It was simple to use and largely acceptable. Big differences were significant by parametric tests but small ones were sometimes significant only with ordinal ones. Within-subject comparisons were more accurate and more sensitive than those between-subjects. The t-test was very robust. 3 Five out of 49 results were erroneously significant; they remained so no matter how the data were handled. It was concluded that this was due to a shift in either perception, cognition or scoring between the two sessions. 4 Arcsine transformations made little difference. The mechanism of these is fully discussed. A conversion to proportional scores resulted in very much improved sensitivity. 5 It is recommended that authors using the visual analogue scale: have valid reason in their own setting for using a transformation; present the distribution, or at least the medians and ranges of their raw scores; also use a simple but different measure so as to demonstrate internal consistency between them.

Adult↗
PubMed1990

[Primary apudomas of the liver].

The literature data on primary liver apudomas with the discussion of their histogenesis, structure, endocrine activity and immunohistochemistry, 36 hepato- and cholangiocarcinomas are studied among which a group of poorly differentiated "atypical" tumours (9 cases) is distinguished. Large areas of endocrine-cell differentiation represented by solid, trabecular and alveolar structures consisting of small lymphocytoid cells or big cells with eosinophil cytoplasm and numerous sinusoid vessels were observed in these tumours. Cytoplasm of these cells contained argyrophylic granules in variable quantity. It is suggested that a certain part of primary liver apudomas is mistaking considered as poorly differentiated "atypical" hepato- or cholangiocarcinomas.

Aged↗
PubMed1995

The AIDS epidemic.

AIDS epidemic began about 15 years ago; since then, the number of new cases have increased over time. By the end of 1994, 1,025,073 AIDS cases had been reported to the WHO, with a 20% increase in the number of cases since December 1993. As is now evident that the majority of cases occur in developing countries, under-diagnosis, under-reporting and delays in reporting explain the big difference existing between reported and estimated AIDS cases, giving a 4.5 million cumulative AIDS cases worldwide, as of late 1994. In the industrialized countries, the spread of HIV infection began in the late 1970's or early 1980's among homosexual men and IVDU's. Heterosexual transmission was, at first, very limited, though recent data has shown an increase in its diffusion. On the contrary, in Sub-Saharan Africa and the Caribbean, transmission was almost exclusively heterosexual. High rates of infection among young women led to a corresponding increase of perinatal transmission, infecting more than 1.5 million children since the beginning of the pandemic. The estimated number of HIV infections worldwide, as of late 1994, is of 17 millions. Thus, even if some evidence indicates a possible decline of the pandemic in industrialized countries over the next few years, probably because heterosexual transmission was less common, developing countries appear to present an increasing number of HIV infections in young people and, consequently, in children. The real impact of such an epidemic is stressed by the fact that HIV is becoming the leading cause of death among, young people, both in industrialized and developing countries.(ABSTRACT TRUNCATED AT 250 WORDS)

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

Report of practicing dentists' activities which serve older people residing in Kentucky's nursing homes.

This state-wide study of dental consultants to nursing homes provides a "first ever" profile of this small but important field in dentistry. As the number of older people continues to grow, particularly in the 85+ age group (which is most likely to be housed in nursing home facilities), the dental profession needs to understand and appreciate its professional obligations to this group of "special" patients. While the data is not absolutely clear, it does appear that perhaps 50% of all of the nursing homes in Kentucky do not have regular staff dentists working with them. Surprisingly, no dental hygienists seemed to be working with dentists, even though they could be quite useful for several types of clinical services and could be a big help with family and staff education projects. Nursing home consultants are dedicated individuals in the middle of their careers. Although gerontology in general and nursing home care, in particular, is primarily a women's field, women dentists in Kentucky are not yet very active in this aspect of dental practice. The list of problems and frustrations facing dentists seems long and difficult to resolve. In spite of this, the dentists working with nursing homes have continued their relationship for many years. While some dentists support more than one nursing home facility, the majority of the dental consultants do limit their efforts to a single nursing home.

Aged↗
PubMed2005

Tissue-specific time courses of spontaneous mutation frequency and deviations in mutation pattern are observed in middle to late adulthood in Big Blue mice.

To better define the time course of spontaneous mutation frequency in middle to late adulthood of the mouse, measurements were made at 10, 14, 17, 23, 25, and 30 months of age in samples of adipose tissue, liver, cerebellum (90% neurons), and the male germline (95% germ cells). A total of 46 million plaque-forming units (pfus) were screened at the six time points and 1,450 circular blue plaques were harvested and sequenced. These data improve resolution and confirm the previously observed occurrence of at least two tissue-specific profiles of spontaneous mutation frequency (elevation with age in adipose tissue and liver, and constancy with age in neurons and male germ cells), a low mutation frequency in the male germline, and a mutation pattern unchanged with age within a tissue. These findings appear to extend to very old age (30 months). Additional findings include interanimal variation in spontaneous mutation frequency is larger in adipose tissues and liver compared with neurons and male germ cells, and subtle but significant differences in the mutation pattern among tissues, consistent with a minor effect of tissue-specific metabolism. The presumptive unaltered balance of DNA damage and repair with age in the male germline has evolutionary consequences. It is of particular interest given the controversy over whether or not increasing germline mutation frequency with paternal age underlies the reports associating older males with a higher incidence of some types of genetic disease. These most detailed measurements available to date regarding the time course of spontaneous mutation frequency and pattern in individual tissues help to constrain hypotheses regarding the role of mutational mechanisms in DNA repair and aging.

Adipose Tissue↗
PubMed1993

Glucose repression of lactose/galactose metabolism in Kluyveromyces lactis is determined by the concentration of the transcriptional activator LAC9 (K1GAL4) [corrected].

In the budding yeast Kluyveromyces lactis glucose repression of genes involved in lactose and galactose metabolism is primarily mediated by LAC9 (or K1GAL4) the homologue of the well-known Saccharomyces cerevisiae transcriptional activator GAL4. Phenotypic difference in glucose repression existing between natural strains are due to differences in the LAC9 gene (Breunig, 1989, Mol.Gen.Genet. 261, 422-427). Comparison between the LAC9 alleles of repressible and non-repressible strains revealed that the phenotype is a result of differences in LAC9 gene expression. A two-basepair alteration in the LAC9 promoter region produces a promoter-down effect resulting in slightly reduced LAC9 protein levels under all growth conditions tested. In glucose/galactose medium any change in LAC9 expression drastically affects expression of LAC9 controlled genes e.g. those encoding beta-galactosidase or galactokinase revealing a strong dependence of the kinetics of induction on the LAC9 concentration. We propose that in tightly repressible strains the activator concentration drops below a critical threshold that is required for induction to occur. A model is presented to explain how small differences in activator levels are amplified to produce big changes in expression levels of metabolic genes.

Base Sequence↗
PubMedDate not supplied

Peptide-based assay for the identification of endothelin-converting enzyme inhibitors.

A simple, solid-phase assay usable for the detection of endothelin-converting enzyme activity and inhibitors has been developed. It uses a multimeric peptide immobilized on microtiter plates that is able to specifically recognize the Big Endothelin fragment 16-32 derivatized with biotin. This fragment is cleaved between residues 21-22 by alpha-chymotrypsin with almost the same proteolysis rate as Big Endothelin, and after enzyme treatment it does not bind to the multimeric peptide adsorbed on the microtiter plates. The amount of uncleaved peptide bound to the plate is detected by subsequent treatment with streptavidin conjugated to peroxidase, followed by a chromogenic reaction. Model inhibitor profiles generated for alpha-chymotrypsin, a protease known to convert Big Endothelin in endothelin, demonstrated the utility of this assay as a rapid high-throughput aid in the study of Big Endothelin enzymatic processing and possibly in the identification of putative enzyme inhibitors.

Amino Acid Sequence↗
PubMed2000

Through a glass, darkly: reflections of mutation from lacI transgenic mice.

The study of mutational frequency (Mf) and specificity in aging Big Blue lacI transgenic mice provides a unique opportunity to determine mutation rates (MR) in vivo in different tissues. We found that MR are not static, but rather, vary with the age or developmental stage of the tissue. Although Mf increase more rapidly early in life, MR are actually lower in younger animals than in older animals. For example, we estimate that the changes in Mf are 4.9x10(-8) and 1.1 x 10(-8) mutations/base pair/month in the livers of younger mice (<1. 5 months old) and older mice (> or =1.5 months old), respectively (a 4-fold decrease), and that the MR are 3.9 x 10(-9) and 1.3 x 10(-7) mutations/base pair/cell division, respectively ( approximately 30-fold increase). These data also permit an estimate of the MR of GC --> AT transitions occurring at 5'-CpG-3' (CpG) dinucleotide sequences. Subsequently, the contribution of these transitions to age-related demethylation of genomic DNA can be evaluated. Finally, to better understand the origin of observed Mf, we consider the contribution of various factors, including DNA damage and repair, by constructing a descriptive mutational model. We then apply this model to estimate the efficiency of repair of deaminated 5-methylcytosine nucleosides occurring at CpG dinucleotide sequences, as well as the influence of the Msh2(-/-) DNA repair defect on overall DNA repair efficiency in Big Blue mice. We conclude that even slight changes in DNA repair efficiency could lead to significant increases in mutation frequencies, potentially contributing significantly to human pathogenesis, including cancer.

5-Methylcytosine↗
PubMed2006

A phylogenetic analysis of the major groups of catfishes (Teleostei: Siluriformes) using rag1 and rag2 nuclear gene sequences.

Higher-level relationships among catfishes were investigated by parsimony, maximum likelihood and Bayesian analyses of two nuclear genes across 110 catfish species representing 36 of 37 families and Conorhynchos (family incertae sedis). Analysis of 3660 aligned base pairs from the rag1 and rag2 genes confirms monophyly of Siluriformes, of most siluriform families and of a number of multifamily groups, some recognized, some novel. South American Loricarioidei are recovered as the sistergroup to other catfishes which are divided into Diplomystidae and Siluroidei. This result contrasts with the prevailing hypothesis that Diplomystidae is the sister to all other catfishes. Monophyly of Siluroidei is supported by rag data including a unique three-codon deletion from rag1. Deep within Siluroidei are 12 large, strongly supported groups with poorly resolved interrelationships. Five are single families: Cetopsidae, Plotosidae, Chacidae, Siluridae and Pangasiidae. Four others are monophyletic taxa ranked here as superfamilies: Clarioidea (Clariidae, Heteropneustidae), Arioidea (Ariidae, Anchariidae), Pimelodoidea (Pimelodidae, Pseudopimelodidae, Heptapteridae, Conorhynchos), Ictaluroidea (Ictaluridae, Cranoglanididae). South American Doradoidea (Doradidae, Auchenipteridae) and Aspredinidae are a sistergroup pair. Sisoroidea (without Aspredinidae), Ailia+Laides, Horabagridae, and Bagridae (without Rita) form a large, predominantly Asian clade, "Big Asia." Mochokidae, Malapteruridae, Amphiliidae, Claroteidae, and African schilbids are united as a species-rich African clade, "Big Africa." The three large continental clades, "Big Asia," "Big Africa" and Neotropical Loricarioidei suggest a prevalence of intracontinental diversification of catfishes. South America is the home of the Gymnotiformes, putative sistergroup of catfishes, plus two of the deepest siluriform clades, Loricarioidei and Diplomystidae, thus suggesting an ancient siluriform presence if not origin there. The rag phylogeny does not identify any African-South American catfish clade. The well-known African-Asian relationships within families Clariidae and Bagridae are confirmed, as is the recently found North American-Asian relationship between Ictaluridae and Cranoglanididae.

Africa↗
PubMed1995

Effect of renutrition on the proliferation kinetics of PHA stimulated lymphocytes from malnourished children.

The fraction of lymphocytes that responded to phytohemagglutinin (PHA) stimulation and initiated cellular proliferation (stimulation index or SI) was determined in groups of healthy and severely malnourished children. SI was determined again in the latter group after a period of nutritional recovery. The proportion of interphasic cells showing PHA response was assessed adding bromodeoxyuridine to the culture, so proliferative nuclei appear big and stain light blue, with dispersed granular chromatin and apparent nucleoli, while non-proliferative nuclei look small, stain red, and have compact and homogeneous chromatin. In mitotic nuclei, differential staining of sister chromatids made it possible to distinguish cells that had gone through one, two and three or more proliferation cycles. Based on the data obtained from interphase nuclei and mitosis, the SI was estimated at 48 and 72 h of culture. SI were higher in lymphocytes from healthy children than in those from children with severe malnutrition, even after the period of nutritional recovery. However, the SI was significantly higher in lymphocytes from malnourished children after nutritional recovery. Although in these children more cells are stimulated, there seems to be still damage that causes a cycling delay.

Bromodeoxyuridine↗