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101.
It is often stated that major biological treatments in psychiatry were discovered by accident or serendipity. Tracing the history of the concept of serendipity, we find that serendipity has been subjected to greatly divergent interpretations. According to the current usage, it is a discovery in which chance was a necessary and/or sufficient condition. With this definition, none of the discoveries of major biological treatments in psychiatry can be labeled serendipitous. The necessary factors common to these discoveries were creative minds that were variably influenced by the zeitgeist and that were persistent in their search for answers. Another important prerequisite was the availability of crucial basic knowledge of many related sciences. We conclude that chance cannot substitute for long-term research and that the latter is the most likely way to lead to valuable discoveries. 相似文献
102.
Irwin M Clark C Kennedy B Christian Gillin J Ziegler M 《Brain, behavior, and immunity》2003,17(5):365-372
Insomnia predicts cardiovascular and non-cardiovascular disease mortality. This study evaluated EEG sleep, nocturnal sympathetic activity, and daytime measures of immune function in subjects with primary insomnia (n = 17) and patients with current major depression (n = 14) as compared to controls (n = 31). Insomniacs showed disordered sleep continuity along with nocturnal increases of average levels of circulating norepinephrine and decreases of natural killer cell responses, whereas depressed patients showed declines of natural killer cell activity, but no differences of EEG sleep or nocturnal catecholamines as compared to controls. Impairments of sleep efficiency correlated with nocturnal elevations of norepinephrine in the insomniacs but not in the depressives or controls. These data indicate that insomnia is associated with nocturnal sympathetic arousal and declines of natural immunity, and further support the role of sleep in the regulation of sympathetic nervous and immune system functioning. 相似文献
103.
OBJECTIVE: To determine whether children's food consumption is increased by the size of the group of children in which they are eating. DESIGN: Crossover study. SETTING: University based preschool. PARTICIPANTS: 54 children, aged 2.5-6.5 years. INTERVENTIONS: Each child ate a standardised snack in a group of three children, and in a group of nine children. MAIN OUTCOME MEASURES: Amount each individual child consumed, in grams. RESULTS: Amount eaten and snack duration were correlated (r = 0.71). The association between group size and amount eaten differed in the short (<11.4 min) versus the long (> or =11.4 min) snacks (p = 0.02 for the interaction between group size and snack duration). During short snacks, there was no effect of group size on amount eaten (16.7 (SD 11) g eaten in small groups vs 15.1 (6.6) g eaten in large groups, p = 0.42). During long snacks, large group size increased the amount eaten (34.5 (16) vs 26.5 (13.8), p = 0.02). The group size effect was partially explained by a shorter latency to begin eating, a faster eating rate and reduced social interaction in larger groups. CONCLUSIONS: Children consumed 30% more food when eating in a group of nine children than when eating in a group of three children during longer snacks. Social facilitation of food consumption operates in preschool-aged children. The group size effect merits consideration in creating eating behaviour interventions. 相似文献
104.
Hennessy A Gillin AG Duggin GG Horvath JS Tiller DJ 《Clinical and experimental pharmacology & physiology》1999,26(11):849-852
1. The purpose of the present study was to examine the effect of nitric oxide (NO) inhibition on mean arterial pressure (MAP), endothelin (ET) and the renin-aldosterone system in pregnancy in the non-human primate (baboon). 2. Twenty pregnant baboons (Papio hamadryas) were examined prospectively after the administration of an oral NO inhibitor in different phases of pregnancy. Haemodynamic responses to NO inhibition, evidence of pre-eclampsia and the renin-aldosterone system were examined under anaesthesia. 3. Oral NL-nitro-L-arginine (NOLA; 5 or 10 mg/kg) was given for 1 week in early (6-8 weeks gestation), middle (14-16 weeks gestation) and late (22-24 weeks gestation) pregnancy and while non-pregnant. Mean arterial pressure, heart rate, haematology, biochemistry, ET, plasma renin activity (PRA) and aldosterone were measured. Foetal effects of NOLA were also examined by ultrasound and neonatal measurements. 4. Nitric oxide inhibition led to an increase in MAP in non-pregnant animals (9 mmHg) and in middle and later pregnancy (6 and 7 mmHg, respectively). Mean arterial pressure in early pregnancy was not affected. A reduction in PRA occurred after NO inhibition in all stages of pregnancy. Significant proteinuria occurred only in late pregnancy. 5. Nitric oxide is involved in the maintenance of lower blood pressure in late pregnancy and inhibition leads to an increase in blood pressure and proteinuria in the baboon. Nitric oxide insufficiency may contribute to the clinical manifestations of human pre-eclampsia. Nitric oxide was not involved in the normal vasodilation of early primate pregnancy. 相似文献
105.
Volumetric rendering of MR images 总被引:1,自引:0,他引:1
The authors developed new techniques for three-dimensional display of magnetic resonance (MR) images that preserve soft-tissue definition, are fully automatic, and work with routinely used section thicknesses. MR images are segmented, selectively enhanced, and displayed by means of a volumetric rendering algorithm. These techniques were used to illustrate normal anatomy of the brain, knee, and liver. Three-dimensional rendering of balanced spin-echo images shows the ventricles and extracerebral veins and of T1-weighted images, the sulci and gyri. The large hepatic and portal vessels can be seen with these enhancement techniques. Three-dimensional views of the knee reveal articular surfaces of the tibia and clearly depict menisci and posterior and anterior cruciate ligaments. These techniques make it possible to image multiple soft tissues simultaneously while preserving the detail contained in the original images. Three-dimensional presentation of complex, overlapping anatomic regions is helpful in surgical planning and should lead to improved diagnosis. 相似文献
106.
Hasegawa BH; Naimuddin S; Dobbins JT d; Mistretta CA; Peppler WW; Hangiandreou NJ; Cusma JT; McDermott JC; Kudva BV; Melbye KM 《Radiology》1986,159(2):537-543
The feasibility of producing patient-specific beam attenuators for chest radiography has been investigated using an anthropomorphic phantom and a human volunteer. A low-dose test exposure is digitized, processed, and used to print a small cerium filter, which is placed in the x-ray beam near the collimator. The final radiograph is recorded on film. The technique results in relatively uniform film exposure, so that structures in all regions of the chest are simultaneously displayed with optimal film contrast. The equalized exposure improves image quality in the normally underpenetrated regions and reduces the role of cross-scatter from the lungs. The image is analogous to optical or computer-processed unsharp masking techniques, but the processing is accomplished in the x-ray beam and results in an improved exposure distribution, giving advantages that cannot be achieved with image processing techniques alone. 相似文献
107.
JC Szepietowski† J Salomon† P Pacan‡ E Hrehorów† A Zalewska§ 《Journal of the European Academy of Dermatology and Venereology》2008,22(7):795-799
The aim of this study was to determine the frequency of body dysmorphic disorder (BDD) identified by Polish dermatologists and to evaluate the treatment modalities applied by them.
Methods A specially designed questionnaire was distributed to 172 dermatologists. A total of 118 doctors responded (68.6%). The dermatologists were asked regarding demographic data, frequency of BDD in their everyday practice and methods of treatment they used in managing BDD patients.
Results During the whole working period, over the half of dermatologists (64%) had observed at least one BDD patient in their practice. One fifth (20%) of the respondents observed 1 or 2 BDD cases during the past 5 years, 14% observed 3 to 5 such patients, 7% observed 5 to 10 BDD cases, and 5% of the doctors reported seeing more than 10 BDD patients within this period. Almost 18% of dermatologists were currently treating a BDD patient. Our data show that 40.7% of the respondents always ask and 28.8% often ask for a psychiatric opinion. More experienced dermatologists statistically more frequently ( P < 0.05) obtained a psychiatric opinion about their patients. Only a small group of dermatologists (15.3%) use their own pharmacological treatment. If they do so, they first use anxiety-relieving drugs and placebo.
Conclusion BDD is a quite common disorder; however, not all dermatologists are sufficiently prepared to treat it. There is an urgent need for training of dermatologists on the effective approach to psychodermatoses. 相似文献
Methods A specially designed questionnaire was distributed to 172 dermatologists. A total of 118 doctors responded (68.6%). The dermatologists were asked regarding demographic data, frequency of BDD in their everyday practice and methods of treatment they used in managing BDD patients.
Results During the whole working period, over the half of dermatologists (64%) had observed at least one BDD patient in their practice. One fifth (20%) of the respondents observed 1 or 2 BDD cases during the past 5 years, 14% observed 3 to 5 such patients, 7% observed 5 to 10 BDD cases, and 5% of the doctors reported seeing more than 10 BDD patients within this period. Almost 18% of dermatologists were currently treating a BDD patient. Our data show that 40.7% of the respondents always ask and 28.8% often ask for a psychiatric opinion. More experienced dermatologists statistically more frequently ( P < 0.05) obtained a psychiatric opinion about their patients. Only a small group of dermatologists (15.3%) use their own pharmacological treatment. If they do so, they first use anxiety-relieving drugs and placebo.
Conclusion BDD is a quite common disorder; however, not all dermatologists are sufficiently prepared to treat it. There is an urgent need for training of dermatologists on the effective approach to psychodermatoses. 相似文献
108.
直到最近为止,冠心病的内科治疗原则仍是降低心肌需氧量。由于粥样硬化病变一直认为是固定不变的狭窄,不可能增加冠脉血流量,因此认为用药物扩张冠状动脉是徒劳的。在近几年内这些概念有了基本转变。然而仅能引起远端心肌内小动脉扩张的药物却起着相反的作用。当心外膜冠状动脉有粥样硬化时,冠状小动脉扩张可加重血流分布异常,导致心肌缺血。冠状循环由近端大冠状动脉及其分枝小动脉组成的心肌内动脉网构成。近端大冠状 相似文献
109.
Mercado S; Hunter DW; Castaneda-Zuniga WR; Amplatz K; Young AT; Cardella JF; Lange PH; Hulbert JC; Reddy P 《Radiology》1986,158(1):207-209
Percutaneous nephrostolithotomy, which can require a double puncture, is presently the method of choice in our institution for the removal of renal stones. Patients that underwent this procedure were evaluated to identify the possible reasons for the double puncture. Of 200 patients evaluated, 14 needed a second tract. The three variables that determined whether a second puncture was needed, in order of importance, were number and size of the stones, with second tracts needed in patients with multiple stones and staghorn calculi; anatomical variations of the renal collecting system itself, with bifid systems the most significant anatomic variation; and the dexterity of the radiologist in performing the puncture and the ability of the urologist to extract the stone. Second tracts were needed more frequently in patients who presented with stones in both the lower and middle poles of the collecting systems. 相似文献
110.
The preservation of red cell antigens at low ionic strength 总被引:1,自引:0,他引:1
Low-ionic-strength saline (LISS) techniques permit a safe and substantial reduction in incubation time and have therefore become the method of choice for antibody detection and compatibility testing in many transfusion laboratories. Consequently, the supply of reagent red cells (RBCs) in a low-ionic-strength preservative solution would remove the daily need for laboratories to wash and resuspend cells in LISS before use. However, the storage of fresh RBCs at low ionic strength in the presence of aminoglycoside antibiotics can cause a rapid loss of certain antigens, possibly as a result of the release of proteolytic enzymes from contaminating white cells. This article describes a low-ionic-strength solution that achieves preservation of antigens on liquid nitrogen-frozen-thawed RBCs for 21 days' storage at 4 degrees C. 相似文献