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排序方式: 共有610条查询结果,搜索用时 15 毫秒
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L B Jensen P Vestergaard A P Hermann J Gram P Eiken B Abrahamsen C Brot N Kolthoff O H S?rensen H Beck-Nielsen S Pors Nielsen P Charles L Mosekilde 《Journal of bone and mineral research》2003,18(2):333-342
The aim of this study was to study the influence of hormone replacement therapy (HRT) on weight changes, body composition, and bone mass in early postmenopausal women in a partly randomized comprehensive cohort study design. A total of 2016 women ages 45-58 years from 3 months to 2 years past last menstrual bleeding were included. One thousand were randomly assigned to HRT or no HRT in an open trial, whereas the others were allocated according to their preferences. All were followed for 5 years for body weight, bone mass, and body composition measurements. Body weight increased less over the 5 years in women randomized to HRT (1.94 +/- 4.86 kg) than in women randomized to no HRT (2.57 +/- 4.63, p = 0.046). A similar pattern was seen in the group receiving HRT or not by their own choice. The smaller weight gain in women on HRT was almost entirely caused by a lesser gain in fat. The main determinant of the weight gain was a decline in physical fitness. Women opting for HRT had a significantly lower body weight at inclusion than the other participants, but the results in the self-selected part of the study followed the pattern found in the randomized part. The change in fat mass was the strongest predictor of bone changes in untreated women, whereas the change in lean body mass was the strongest predictor when HRT was given. Body weight increases after the menopause. The gain in weight is related to a decrease in working capacity. HRT is associated with a smaller increase in fat mass after menopause. Fat gain protects against bone loss in untreated women but not in HRT-treated women. The data suggest that women's attitudes to HRT are more positive if they have low body weight, but there is no evidence that the conclusions in this study are skewed by selection bias. 相似文献
3.
Diabetic rats display changes in opioid pharmacology and brain regional levels of opioid peptides and prodynorphin mRNA. Previous investigations of opioid receptor binding, carried out in whole-brain homogenates, have, however, failed to detect changes. In the present study, quantitative autoradiography was used to measure μ and κ opioid receptor binding in discrete brain regions of streptozotocin-treated diabetic rats. Measurement was limited to regions that previously displayed opioid binding changes in chronically food-restricted rats, since our primary aim is to identify brain mechanisms that mediate adaptive responses to persistent metabolic need and adipose depletion. Diabetics displayed strong trends or statistically significant changes which matched seven of the thirteen binding changes observed in food-restricted rats. In no case did diabetics display changes in the opposite direction. The two statistically significant changes common to food-restricted and diabetic rats are increased κ binding in the medial preoptic area and decreased μ binding in the lateral habenula. The possible functional significance of these changes is discussed. 相似文献
4.
Jan Abrahamsen Ove A. Nedergaard 《Naunyn-Schmiedeberg's archives of pharmacology》1989,339(3):281-287
Summary The purpose of this investigation was to study the effect of adrenaline on presynaptic adrenoceptors by recording the release of 3H-noradrenaline evoked by electrical-field stimulation. Adrenaline (10–10–3 × 10–9 mol/l) had no effect on the 3H-overflow evoked by stimulation of aorta preloaded with 3H-noradrenaline. At 10–8 and 3 × 10–8 mol/l, the 3H-overflow was decreased by up to 47%. The maximum decrease was more marked in the presence of either cocaine (3 × 10–5 mol/l) plus corticosterone (4 × 10–5 mol/l), cocaine (3.3 × 10–6 mol/l) plus normetanephrine (4 × 10–5 mol/l), or desipramine (10–6 mol/l) plus normetanephrine (10–5 mol/l). The relationship between adrenaline-induced decrease and stimulation-frequency was dependent on the experimental design: either the decrease was the same at all frequencies (1–16 Hz) or it was more marked, the lower the frequency (1 > 3 > 8 Hz). Phentolamine and rauwolscine (both 10–6 mol/l) antagonized the inhibitory effect of adrenaline (10 – 8–10–6 mol/l). Phenoxybenzamine (10–6 mol/l), prevented the inhibitory effect. No enhancing effect of adrenaline (10–9–10–6 mol/l) was observed in the presence of these three -adrenoceptor antagonists. Our results suggest that adrenaline activates inhibitory 2-adrenoceptors, but not facilitatory -adrenoceptors on postganglionic sympathetic nerve terminals in rabbit aorta.
Send offprint requests to J. Abrahamsen at the above address 相似文献
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D. Hongve O. K. Skogheim A. Hindar H. Abrahamsen 《Bulletin of environmental contamination and toxicology》1980,25(1):594-600
Conclusions The tested heavy metal concentrations: Cd, Cu5·10–8M, Zn, Pb5·10–7M, Hg5·10–9M, and a mixture with the concentrations of each metal ten times more dilute, had inhibitory effects on the photosynthesis of phytoplankton from Lake Tyrifjorden. A moderate increase in the water's turbidity or colour reduced the biological availability of the metals and thus their effect on the photosynthetic rate. The increase in anthropogeneous metal load which has taken place in most watercourses may thus be counteracted by the natural influence of dissolved organic matter and by processes in lakes and rivers causing increased turbidity.NTA led to detoxification of Cd, Zn, Pb, and Cu while Hg and the metal mixture became more toxic. An increase in NTA concentration may be the result if this substance comes into use as a substitute for phosphorus in detergents. In Lake Tyrifjorden this may have some unwanted implications since the sediments in the deeper part of the lake are severely contaminated by mercury (HONGVE and SKOGHEIM unpubl.), and NTA may release this as an NTA-Hg complex to the water (CHAU and SHIOMI 1972). NTA complexations of mercury adsorbed to the sediment may thus give a new and quantitatively important contribution to the internal cycle of mercury in the lake. It will also give directly, without microbiological methylation, a substance which may affect the plankton photosynthesis at a concentration which is only a little higher than the present concentration of mercury in the water. 相似文献
7.
Haemodynamic studies were performed at rest and during exercise in five chronic haemodialysis patients at two different states of hydration, called "normal hydration" and "over-hydration" (mean change in body weight 2.9 kg). Apart from an increase in mean aortic pressure and cardiac index there were no signs of cardiac dysfunction at rest at normal hydration. On exercise the mean pulmonary artery and wedge pressure increased significantly while cardiac output doubled. Overhydration caused considerable increases in right and left sided heart pressures at rest, without any increase in cardiac index. These changes became more pronounced during exercise. Anaemia and arteriovenous shunting make dialysis patients very sensitive to volume load. Extreme anaemia should be avoided, and keeping dialysis patients in a state of low volume load should be given high priority. 相似文献
8.
Jan Abrahamsen Ove A. Nedergaard 《Naunyn-Schmiedeberg's archives of pharmacology》1991,343(2):161-165
Summary The aim of the present investigation was to examine whether or not presynaptic facilitatory -adrenoceptors are detectable on the postganglionic nerves in the rabbit isolated ear artery. Strips of rabbit central ear artery were incubated with 3H-noradrenaline (10–7 mol/l; 30 min or 10–6 mol/l; 60 min). Subsequently, they were washed repeatedly with physiological salt solution. The strips were subjected to electrical-field stimulation (S1–S8) and the resultant 3H-overflow was determined.When the ear artery was stimulated with 150 pulses (0.5 ms; 3 Hz; 225 mA), isoprenaline (10–9–10–6 mol/l) either alone or in the presence of either rauwolscine (10–6 mol/l) or phentolamine (10–6 mol/l) did not alter the stimulation-evoked 3H-overflow. This was also the case in the presence of rauwolscine (10–6 mol/l) plus either the selective phosphodiesterase inhibitor ICI 63 197 (3 × 10–5 mol/l) or forskolin (10–6 mol/l). When the ear artery was stimulated with 300 pulses (1 ms; 5 Hz; 225 mA), isoprenaline had no effect on the stimulation-evoked 3H-overflow. This was also the case when phentolamine (10–6 mol/l) was present. Propranolol (10–7–10–5 mol/l) did not alter the stimulation-evoked 3H-overflow. In some experiments, the stimulation current was reduced to 175 mA in order to obtain similar reference release (S3) values despite the presence of rauwolscine (150 pulses; 0.5 ms; 3 Hz). Even then, isoprenaline (10–9–10–6 mol/l) did not change stimulation-evoked 3H-overflow. The results suggest that postganglionic sympathetic nerves in rabbit central ear artery do not possess presynaptic facilitatory -adrenoceptors.
Send offprint requests to J. Abrahamsen at the above address 相似文献
9.
Summary
Forty-three of fifty-eight (74.1%) female patients with fibromyalgia completed an eight-week treatment period testing the combination of carisoprodol, paracetamol (acetaminophen) and caffeine versus placebo. Twenty-three patients received placebo and twenty active medication. In the placebo group 56.5% of the patients used additional analgesics or nonsteroidal anti-inflammatory drugs compared to only 20% in the active treatment group (p=0.015). Forty-three percent of the patients in the placebo group and none of the patients in the active treatment group used tricyclic antidepressants, anxiolytics or sedatives (p=0.0008). Active treatment gave statistically significant improvement after treatment for pain (p<0.01), for sleep quality (p<0.01) and for the general feeling of sickness (p<0.05). In the active treatment group increased pressure pain threshold after eight weeks was found at 70% of the sites measured, while the pressure pain threshold was increased at only 30% of the sites in the placebo group. In the placebo group improvement was found for the pain and sleep quality (p<0.05). This improvement may in part be due to the large amounts of extra medication in this group. Thus, the combination of carisoprodol and paracetamol (acetaminophen) and caffeine are effective in the treatment of fibromyalgia. 相似文献
10.
Abrahamsen Bjarke Burghle Alaa Hassan Rossing Charlotte 《International journal of clinical pharmacy》2020,42(2):315-320
International Journal of Clinical Pharmacy - In recent years, increased longevity of the Danish population has resulted in a growing segment with age-related and chronic health conditions. This,... 相似文献