[Spanish scientific production in the cardiovascular area through Science Citation Index (1990-1996)]. / La producción científica española en el área cardiovascular a través del Science Citation Index (1990-1996).

INTRODUCTION AND OBJECTIVES: A bibliometric analysis of the Spanish scientific production in the Cardiovascular research area constitutes a useful approach to the study of the scientific activity conducted in the field. The most relevant aspects of the research and their evolution over time are analysed. MATERIAL AND METHODS: Publications covered by the Science Citation Index database under the heading "cardiovascular system" during the years 1990-1996 and signed by at least one Spanish address were studied. The distribution of the scientific production by geographic areas and institutional sectors was analysed and the most productive centers were identified. RESULTS: During these years, the scientific production in Cardiovascular research showed a growing rate of 83%, slightly lower than that of Biomedicine in Spain. A total of 1,434 documents were analysed (3% of the biomedical production), with 24% of meeting-abstracts. Although the production was concentrated in Madrid (33%) and Cataluña (30%), Cantabria and Navarra emerged when the values were normalised according to either R&D expenditures or population data. The most productive institutional sectors were Hospitals (86%) and Universities (22%). The most productive centres were identified, as well as their growth rate, their activity index and the average impact factor of the journals used. More than 50% of the documents were performed in collaboration among different centres. International collaboration showed an upward trend (from 16% to 21%). CONCLUSIONS: Spanish Cardiovascular research showed an increasing international visibility over the studied period, as shown by the growing number of publications in the Science Citation Index database, the up-rising trend towards high-impact-factor journals, and the ever-growing collaboration of Spanish authors with foreign partners.

[Evaluation of the scientific activity through bibliometric indices]. / Evaluación de la actividad científica a través de indicadores bibliométricos.

The scope of bibliometric studies is the treatment and quantitative analysis of scientific publications. They belong to the so-called "social studies of science", and science policy constitutes one of its main applied fields. These studies efficiently complement the opinions and judgements of experts, thus providing objective and useful tools for evaluating the results of scientific activity. Nevertheless, given the impact that these evaluations have on the assignment of funding for research and even on the professional career of investigators, it becomes essential to know in detail the characteristics of bibliometric indicators and the limitations of their use. The Science Citation Index database is one of the most employed. In the case of biomedical research it is useful to analyze the most internationally visible scientific production, since it satisfactorily covers biomedical journals; however, clinical research with local interest published in Spanish journals is not included in that database. Widely employed bibliometric indicators are those measuring scientific activity through the number of publications, those based on the citations received by published studies and, in between them, the impact of journals. The impact factor is an indicator very used in bibliometric studies; though occasionally a high impact factor is assumed to reflect high quality, this indicator specifically measures visibility and diffusion of the works published by these journals rather than their scientific quality.

[Scientific activity of the most productive Spanish research teams in pharmacology and pharmacy during the period 1986-1993 as covered by the Science Citation Index (SCI)]. / Actividad científica de los grupos españoles más productivos en farmacología y farmacia durante el período 1986-1993 a través del Science Citation Index (SCI).

BACKGROUND: Bibliometric analyses at the research team level in the pharmacology and pharmacy (F&F) subfield allow in-depth analysis of the findings obtained at higher aggregation levels. MATERIAL AND METHODS: Publications of Spanish authors in pharmacological journals covered by the Science Citation Index (SCI) are studied and the most productive Spanish teams during 1986-1989 and 1990-1993 are identified through in-house programmes based on co-authorship analysis. Team composition is defined and team size, scientific output, productivity, expected impact factor and collaboration pattern of the most productive teams are analysed as well as its evolution over time. RESULTS: The observed annual increasing rate in the number of publications and authors in the field (11%) was similar to that of the number of researchers in the Spanish scientific system (8%). The number of highly productive teams doubled from the first to the second period (28 and 61 teams, respectively). The average team size was 8 researchers, showing an average scientific output of 3 documents/year and an average, productivity of 1.7 publications per author and team in each period. Over the years, an increase in the expected impact factor (EIF) of the publication journals and significant changes in the team composition were observed. A total of 13 stable teams were identified, with a greater size and output than the rest of the groups, and showing an upward trend in their expected impact factor and international collaboration rate. Stable teams did not show the negative correlation between team size and productivity observed for the total of the highly productive teams. CONCLUSIONS: The F&F subfield is in a very dynamic stage, with a great increase in the number of researchers, starting of new teams and consolidation of others. A trend was observed towards the concentration of activity in the most productive teams, that are the most visible internationally both in number of publications in the SCI and in the impact factor of the publication journals.

[Spanish scientific production in biomedicine and health sciences during the period 1990-1993 (Science Citation Index and Social Science Citation Index) and comparison to period 1986-1989]. / Producción científica española en biomedicina y ciencias de la salud durante el período 1990-1993 (Science Citation Index y Social Science Citation Index) y comparación con el período 1986-1989.

BACKGROUND: In 1993 a first study on the scientific production of Spain in 1986-1989 on Biomedicine and Health Sciences, through the Science Citation Index (SCI) was published. The analysis attained the level of centres, with special emphasis in those related to the Health Care System. This paper analyses the period 1990-1993, offers a wider coverage including the Social Science Citation Index (SSCI) database, and compares both time periods. MATERIAL AND METHODS: Documents indexed by SCI and SSCI, CD-ROM version, with at least one Spanish address, published in biomedical and medical journals during the years 1990, 1991, 1992 and 1993, have been studied. Quantitative and qualitative bibliometric indicators for the analysis by subject matter, geographic distribution, institutional sector and centre of origin have been used. Global data were also analysed according to economic and human resources. RESULTS: A total of 21,434 documents were studied, of which 67.9% were journal articles. The highest contributors were Universities (48.8% of the documents) and Hospitals (45.3%). The autonomous communities of Madrid (31.9%) and Catalonia (26.9%) concentrate more than half the production-developed principally by hospitals-followed by Andalucía (11.7%) and C. Valenciana (7.8%). The most active disciplines were biochemistry/molecular biology (13%), neurosciences/neurology (8.4%), pharmacology/pharmacy (8.4%) and medicine, general/internal (7.9%). Comparing the results with period 1986-1989, some of the differences observed could be explained by the fact of MEDICINA CLINICA being included in SCI since 1992. An increase in the number of citable items (72.9%), number of journals used (from 1,086 to 1,346) and international cooperation rate (13.5% to 18.3%) was detected. The institutional sectors with the highest growth rate were Hospitals (92.9%) and Consejo Superior de investigaciones Cientificas (CSIC) (119.3%). Scientific production and visibility of publications (measured as impact factor of journals used) grew in most disciplines, being the quantitative increase greater in cancer/oncology, gastroenterology/hepatology, genetics/heredity and cardiovascular system. No substantial changes as to geographic distribution of documents or most active centres were observed. CONCLUSIONS: Spanish scientific activity grew steadily every year and its visibility improved, being the Health sector one of the main actors. When comparing both four-year period. Spain moved up from the seventh to the sixth position in the ranking of EU countries according to its scientific output in biomedicine and health sciences.

Suppressor effect of morphine on the pancreatic polypeptide response to insulin-induced hypoglycemia in man.

The effect of intravenous infusions of morphine and naloxone, alone or in combination, on basal plasma pancreatic polypeptide (PP) levels as well as on the PP response to insulin-induced hypoglycemia in normal subjects was investigated. Morphine infusion (150 micrograms/kg/120 min, intravenously) induced a progressive decrease in the basal plasma PP levels (basal value: 158 +/- 42 pg/mL; nadir, at 120 minutes: 108 +/- 26 pg/mL; P less than 0.05). In control experiments, insulin injection was followed by a 10-fold plasma PP elevation (peak: 1258 +/- 71 pg/mL). During morphine infusion, the PP response to hypoglycemia appeared consistently reduced (peak: 404 +/- 117 pg/mL, P less than 0.05 vs. control). Naloxone pretreatment (4.8 mg, intravenously) partially reversed the blocking effect of morphine on the PP secretion evoked by insulin-induced hypoglycemia (peak: 977 +/- 133 pg/mL, P less than 0.05 vs. control and morphine experiments). Similar degrees of hypoglycemia were achieved with and without morphine or naloxone. The intravenous infusion of naloxone alone failed to significantly modify both basal circulating PP levels and the PP response to hypoglycemia. The observation that morphine reduces PP output, both the basal value and that elicited by a parenteral stimulus, indicates that this effect is independent of its action on the gastrointestinal tract. On the other hand, the lack of effect of naloxone alone on PP secretion argues against the participation of endogenous opiates in the control of this process.

Inhibitory effect of somatostatin-28 on pancreatic polypeptide, glucagon and insulin secretion in normal man.

We have compared the effects of equimolar doses of intravenous somatostatin-28 (SS-28) and somatostatin-14 (SS-14) (250 micrograms and 125 micrograms, respectively) on the secretion of pancreatic polypeptide (PP), glucagon and insulin evoked by a protein-rich meal in normal subjects. Both peptides reduced the fasting plasma levels of these hormones and completely abolished their responses to the alimentary stimulus; in addition, they caused an early decrease of plasma glucose followed by a hyperglycemic phase. As compared to SS-14, SS-28 elicited a longer-lasting inhibition of PP and insulin secretion and displayed greater hypo- and hyperglycemic effects. A somatostatin-like component, similar to SS-28, has been identified in pancreatic extracts as well as in peripheral plasma. Thus, it might be hypothesized that this peptide plays a role in the control of pancreatic hormone release.

Characterization of the pancreatic polypeptide response to hypoglycemia in man.

The human pancreatic polypeptide (hPP) responses to insulin injection (0.05-0.1 U/kg, i.v.) and to endogenous insulin release as provoked by i.v. tolbutamide (1 g) and oral glucose administration (1.75 g/kg) have been examined. The injection of insulin or tolbutamide was followed by a marked elevation of circulating hPP which was abolished by preventing the hypoglycemic effect of these substances by intravenous glucose infusion. Atropine pre-treatment (1 mg, i.v.) also blocked the hPP responses to insulin- or tolbutamide-induced hypoglycemia. Approximately three hours after glucose ingestion, coinciding with the hypoglycemic phase of the test, there was a clear-cut increase in circulating hPP. This hPP response was blunted by impeding the blood sugar fall to sub-baseline values-by means of a glucose infusion-as well as by prior atropinization. It is concluded that: 1) The hPP secretagogue activity of both, insulin and tolbutamide is mediated by their hypoglycemic effect. 2) The elevation of circulating hPP, which occurs during the late hypoglycemic phase of an oral glucose test, is also dependent upon the blood sugar decline to sub-baseline values. 3) Under the above conditions, the hPP response to hypoglycemia can be blocked by atropine, thus indicating that it is due to activation of the cholinergic system and not to the direct effect of glucose lack at the level of the hPP-cell.