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11.
The influence of a low-dose combined oral contraceptive (ethinyl estradiol 30 micrograms + desogestrel 0.15 mg) on menstrual blood loss (MBL) was evaluated in 20 healthy, young women. MBL prior to commencing oral contraception was 60.2 +/- 5.6 ml (range 22-116 ml), and decreased (p < 0.001) to 36.5 +/- 5.2 ml (range 7-80 ml) and 33.7 +/- 4.1 ml (range 5-70 ml) after 3 and 6 months' oral contraceptive medication, respectively. The reduction in MBL during oral contraception was most apparent during the first two days of menstruation. Five women had an MBL > 80 ml prior to commencing oral contraceptive medication. In all of these women, MBL during the 6th menstrual period after commencing oral contraception was < 80 ml. All the women included in this study had a normal blood hemoglobin concentration, hematocrit and erythrocyte indices and there were no significant changes in these variables during the course of the study. Serum ferritin concentration prior to commencing oral contraception was 44.2 +/- 9.0 micrograms/l and was largely unchanged after 6 months' oral contraception (39.7 +/- 6.3 micrograms/l). On admission to the study, two women had a serum ferritin < 10 micrograms/l, indicative of low iron stores. Both these women had an MBL > 80 ml at the baseline assessment. Serum ferritin concentration increased during oral contraceptive medication in both women (from 8.5 micrograms/l to 12.0 micrograms/l and from 5.4 micrograms/l to 6.8 micrograms/l, respectively). The duration of menstruation (p < 0.01) and the number of women suffering from dysmenorrhea (p < 0.05) was reduced during oral contraception. 相似文献
12.
S. Lindgren S. Larsson M. Holgerssonr B. Bake 《Clinical physiology and functional imaging》1994,14(2):169-179
Summary. To investigate the ability of various lung-function tests to demonstrate dilatation of peripheral airways, ten asthmatics inhaled increasing doses of a f2-agonist by two different and controlled techniques. Low inspiratory flow with a long post-inspi-ratory pause favoured peripheral deposition, and a high inspiratory flow with a short post-inspiratory pause favoured central deposition of drug in the airways. Ordinary spirometry, maximum expiratory flow rates after breathing air as well as a helium-oxygen mixture, a single breath N2-test and resistance of the respiratory system were obtained before and after each of five terbutaline doses with both inhalation techniques. By using a double-dummy technique, the study could be performed double blinded. Effects were compared at doses giving equal effects on PEF, assumed to represent equal deposition of bronchodilator and effects on central airways. At such ‘iso A PEF doses’, particularly FVC and the slope of phase III of the N2-test improved more following the slow inhalation technique. It is concluded that changes in those tests reflect dilatation in peripheral airways in asthmatics., 相似文献
13.
Straight leg raising test versus radiologic size, shape, and position of lumbar disc hernias. 总被引:3,自引:0,他引:3
In 30 patients with a computed tomography-verified lumbar disc herniation, the relation between the straight leg raising test and the size, shape, and position of the hernia was evaluated before, 3, and 24 months after inception of nonoperative treatment. Hernia size was expressed as an index relating it to the size of the spinal canal. The limitation of the straight leg raising test was not related to size or position of the hernia. Before treatment, straight leg raising was equally restricted in patients with sharply pointed or blunt hernias, but after 3 months straight leg raising was less limited in patients with sharply pointed hernias, whereas after 24 months straight leg raising was regularly normalized. Size index was lower for sharply pointed hernias at all three computed tomography scans. A decrease in hernia size over time, irrespective of shape, was not correlated to a concomitant improvement in straight leg raising. It must be presumed that additional factors, such as inflammatory reactions affecting the nerve roots, are of importance for the magnitude of straight leg raising. 相似文献
14.
Laying hens are very efficient producers of antibodies and provide an interesting alternative for large-scale production of specific antibodies. These antibodies also have biochemical advantages over mammalian antibodies (e.g. rabbit antibodies) that can be used to improve immunoassays where antibodies are used. The concentration of IgY in egg yolk is an important production parameter. The purpose of this study was to investigate the genetic variation of IgY levels in egg yolk. We have compared IgY concentrations in egg yolks from two lines, selected for egg production traits at the Swedish University for Agricultural Sciences (Single Comb White Leghorn and Rhode Island Red) and a cross between the two lines (SLU-1392). Single Comb White Leghorns have the highest mean concentration of yolk IgY, 2.21 mg ml-1 compared to SLU-1392 1.95 mg ml-1 and Rhode Island Red 1.68 mg ml-1. The cross thus had an intermediate IgY concentration in relation two the two other lines. There were great differences between individual animals within each line. Our results indicate that it should be possible to increase yolk antibody production by using a high producing chicken line and by genetic selection within the line. We found three individuals with very low yolk IgY concentrations among the Rhode Island Red hens. Newly hatched chickens with limited amounts of IgY from the hen may be more susceptible to infections. 相似文献
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17.
Mauri J. Marttunen Hillevi M. Aro Markus M. Henriksson Jouko K. Lönnqvist 《European child & adolescent psychiatry》1994,3(2):101-110
Detailed characteristics of adolescent suicides (aged 13–19 years) with adjustment disorders (AD) (N=11) or no psychiatric diagnosis (N=3) in a nationwide adolescent suicide population (N=53) from Finland are presented. The data were collected in a psychological autopsy study of all suicides in Finland (N=1397) during a 12-month period in 1987–1988. Data collection included thorough interviews with the victims' family members and professionals, and information from official records. All the suicides with AD or no diagnosis were males. Most of these victims used highly lethal suicide methods. Previous psychiatric treatment and previous suicide attempts were rare. They were seldom under the influence of alcohol when committing suicide. The process leading to suicide seemed to be of relatively short duration. According to informant reports, withdrawn or narcissistic individual characteristics predominated in many cases. Psychosocial stressors preceding suicide often involved interpersonal losses or conflicts. Talking of suicidal intentions prior to the act was common, indicating the need to take seriously all adolescents' expressions of intended suicide, even in the absence of explicit psychopathology.
Zusammenfassung Es werden detaiilierte Beschreibungen von Selbst-morden im Jugendalter, verbunden mit Anpassungsstörungen (N=11) oder keiner psychiatrischen Diagnose (N=3) vorgestellt. Diese stammten aus der Gesamtheit aller jugendlichen Selbstmörder (N=53) aus Finnland. Die Daten wurden in einer psychologischen Obduktionsstudie aller Selbstmörder Finnlands (N=1397) während eines einjährigen Zeitraumes zwischen 1987 und 1988 gesammelt. Die Datenerhebung umfaßte ausgiebige Interviews mit den Familienmitgliedern, beteiligten Fachkräften und Informationen von offizieller Seite. Die Selbstmörder mit Anpassungstörungen oder keiner Diagnose waren alle männlich. Die meisten dieser Opfer benützten sehr letale Suizidmethoden. Vorangegangene psychiatrische Behandlungen und Selbstmordversuche waren selten. Sie standen nur selten unter dem Enfluß von Alkohol, als der Selbstmord vollzogen wurde. Der Prozeß, der zu dem Suizid führte, schien von relativ kurzer Dauer zu sein. Entsprechend den Angaben der Informanden prädominierten in vielen Fällen zurückgezogene oder narzißtische Persönlichkeitsmerkmale. Psychosoziale Stressoren, die dem Suizid vorangingen, umfaßten interpersonelle Verluste oder Konflikte. Häufig wurde über die Suizidabsichten vor der Tat gesprochen. Dies verdeutlicht die Notwendigkeit, alle Suizidäußerungen von Jugendlichen ernstzunehmen, selbst dann, wenn eine explizite Psychopathologie fehlt.
Résumé Les caractéristiques détaillées de suicides d'adolescents (âgés de 13 à 19 ans) avec troubles avec l'adaptation (AD) (N=11) ou l'absence de diagnostic psychiatrique (N=3) sur une population de suicides d'adolescents s'étendant sur l'ensemble du pays (N=53), la Finlande sont présentées. Les faits ont été collectés dans le cadre d'une étude d'autopsie psychologique de tous les suicides en Finlande (N=1397) pendant une période de 12 mois 1987–1988. Le recueil des faits incluait des interviews avec les membres de la famille des victimes et les professionels ainsi que les informations provenant de documents officiels. Tous les suicides avec un trouble de l'adaptation ou sans diagnostic étaient masculins. La plupart de ces victimes utilisait des méthodes hautement mortelles. Les traitements psychiatriques précédents et les tentatives précédentes de suicides étaient rares. Ils étaient rarement sous l'influence de l'alcool quand ils ont commis les suicides. Le processus conduisant au suicide semblait être de durée relativement brève. Selon les rapports d'information, une attitude de retrait ou des caractéristiques individuelles de retrait prédominaient dans la majorité des cas. Les facteurs de stress psycho-sociaux précédent le suicide impliquaient souvent des pertes inter-personnelles ou des conflits. Parler du désir du suicide devant le passage à l'acte était habituel indiquant la nécessité de prendre au sérieux tous les adolescents exprimant le désir de suicide, même en l'absence d'une psychopathologie explicite.相似文献
18.
The neutron capture reaction 10B(1n,4He)7Li produces two energetic particles, 4He2+ and 7Li3+ that are strongly cell toxic. Due to the short range of these nuclear fragments (5-9 microns) mainly those cells that have bound or internalized a 10B-containing substance are growth-inactivated. The most critical and difficult step in an efficient boron neutron capture therapy (BNCT) is the tumour targeting. It is today possible to synthesize a large number of boron compounds and conjugate them to tumour-seeking macromolecules, such as monoclonal antibodies or different polypeptides. The boron-containing substances presently considered for therapy are sulfhydryl boron hydride (BSH) and boron-phenylalanine, (BPA) for the treatment of gliomas and malignant melanomas respectively. Other boronated compounds considered are ligands for receptor-amplified tumour cells, antibodies for tumour cells with specific antigens and thioureas for treatment of melanotic melanomas. The required boron concentration is given by the relative dose due to neutron capture in 10B and that of the competing capture reactions in nitrogen and hydrogen. Capture in nitrogen produces protons with a range of about 10-11 microns and this gives a radiation dose to all cells in the neutron activated area. Calculations show that the local concentration of 10B near the critical radiation target, DNA, must be higher than 10 ppm (10 micrograms/g). Increased emphasis will be put on the development of combinations of treatments that fulfil the requirements for attacking the microscopic spread of the tumour. 相似文献
19.
A. Larsson Ch. Jensen M. Bilting S. Ekholm H. Stephensen C. Wikkelsö 《Acta neurochirurgica》1992,117(1-2):15-22
Summary Thirteen patients with normal pressure hydrocephalus were operated upon with an externally manoeuvrable shunt system (Sophy SU8) in order to investigate its influence on clinical outcome, intracranial pressure and cranial CT parameters. The opening pressure was set at high at surgery and lowered stepwise at intervals of three months to medium and low. The clinical condition, intracranial pressure and cranial CT parameters were examined at the end of the 3 months interval on each pressure level.The patients improved within the first 3 months inspite of an unchanged mean intracranial pressure and remained in a stable clinical condition during the rest of the study period. The intracranial pressure was significantly reduced at 9 months. The ventricular index, Evans index, temporal horn and third ventricle width were reduced 3 months post-operatively and did not change significantly during the rest of the study. The pre-operative third ventricle width was correlated to high psychometric test results after shunt surgery. Reduction in ventricular index, Evans index and third ventricle width after surgery correlated to improvement in psychometric scoring.The clinical improvement after shunt surgery for normal pressure hydrocephalus is seen within 3 months and is independent of the adjusted valve pressure. 相似文献
20.
Evidence has been reported that clozapine may derive part of its therapeutic effects in treatment-resistant schizophrenic patients by interacting with the serotonin system. Among the few behavioural models available to test the hypothesis of an interaction of clozapine with 5-HT2 receptors, male rat sexual behaviour is particularly useful, since in this behaviour 5-HT1A and 5-HT2 receptors have opposite functions. Stimulation of 5-HT1A receptors facilitates ejaculatory behaviour and stimulation of 5-HT2 receptors inhibit ejaculation. In the present study, male rat sexual behaviour was depressed by treatment with DOI (1.0 mg/kg), a selective 5-HT2 receptor agonist. The depressive effect of DOI was attenuated by the administration of clozapine (0.1–1.0 mg/kg) in doses that by themselves did not significantly affect sexual behaviour. It was concluded that clozapine in the male rat sexual behaviour model may be interpreted as serving as a 5-HT2 antagonist. 相似文献