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91.
We have experienced a case of angiosarcoma of the chest wall in a patient with fibrous dysplasia. The patient was a 64-year-old man and had large bilateral thoracic masses. Each tumor, resected metachronously with the chest wall, was diagnosed as angiosarcoma. One of these tumors had a histological component of fibrous dysplasia. The patient died from brain metastasis 19 months after the first operation. Angiosarcoma associated with fibrous dysplasia of the chest wall is very rare. 相似文献
92.
93.
Laminin-immunoreactive sites are induced by growth-associated triggering factors in injured rabbit optic nerve 总被引:2,自引:0,他引:2
We have previously demonstrated that application of soluble growth-associated triggering factors (GATFs) from regenerating fish optic nerve or neonatal rabbit optic nerve to a non-regenerative crushed adult rabbit optic nerve provokes regeneration-like changes in the adult rabbit. In this study we show that the responses initiated by GATFs also include a change in pattern of appearance of an extracellular matrix component, laminin, known to play a role in neurite outgrowth and elongation. These findings suggest a mechanism whereby GATFs activate the adult rabbit glial cells to produce or to accumulate laminin and thereby allow partial compensation for the low inherent regenerative ability of the adult rabbit optic nerve. 相似文献
94.
R. A. Joachim O. Noga V. Sagach G. Hanf H. Fliege R. D. Kocalevent E. M. Peters B. F. Klapp 《Clinical and experimental allergy》2008,38(2):283-290
Background Asthma is a chronic disease defined by airway inflammation, increased airway hyperresponsiveness and episodes of airway obstruction. Although there are abundant clinical and experimental data showing that stress may worsen asthma, the mechanisms linking stress to asthma are not well understood. By inducing a pro‐inflammatory cytokine milieu, stress might enhance airway inflammation in bronchial asthma. We therefore investigated the correlation of stress perception and the cytokine profile of circulating lymphocytes in humans. Methods Allergic asthmatic patients and healthy controls were evaluated for perceived level of stress, demographic and lung function data. Whole blood cells were obtained and stimulated by mitogen to assess intracellular IL‐4, IFN‐γ and TNF‐α by flow cytometry. Neurotrophins nerve growth factor (NGF) and brain‐derived neurotrophic factor (BDNF) were measured in serum. Results Asthmatic patients showed significantly higher percentages of TNF‐α‐producing T cells than healthy controls. Only in asthmatic patients was stress perception correlated with percentages of TNF‐α‐producing T cells and serum BDNF levels, while forced expiratory volume in 1 s (% predicted) was negatively correlated to BDNF. Conclusion The results of our study support the hypothesis that stress deteriorates bronchial asthma by inducing a pro‐inflammatory cytokine profile in allergic asthmatics. Stress management might provide a supplement therapy of allergic asthma. 相似文献
95.
Contralaterally projecting lamina VIII interneurones in middle lumbar segments in the cat 总被引:5,自引:0,他引:5
Peripheral input to lamina VIII interneurones was investigated by using extracellular and/or intracellular records from them. The interneurones were located in the L4-L5 spinal segments and projected to contralateral motor nuclei in the L7 segment. They constituted a non-homogeneous population but their input from muscle afferents (mainly group II afferents of quadriceps, flexor digitorum longus and pretibial flexors and group I afferents of triceps surae and hamstring nerves) and from cutaneous and joint afferents resembled the input to ipsilaterally projecting laminae V-VII interneurones of the same segments rather than the input to more caudally located lamina VIII interneurones. Since the ipsilaterally projecting laminae V-VII interneurones with such an input might be involved in locomotion, it is proposed that this is also the case for the contralaterally projecting lamina VIII midlumbar interneurones, especially those excited by stimuli applied in the cuneiform nucleus (mesencephalic locomotor region). 相似文献
96.
Glycogen synthase (GS) activity was characterized in rat brown adipose tissue (BAT) and the activity was found to be much higher than that in white adipose tissue. Prolonged starvation had no effect on the active form of GS, as found in the liver and muscle. The GS activity was similar in BAT of rats housed in an animal room (21 +/- 1 degree) whether they were fed on high-carbohydrate, high-fat, or stock diets. Acclimatization of rats to cold (4 +/- 1 degree) for 2 weeks significantly increased GS activity. This increase in the cold was fivefold greater when rats were fed on high-carbohydrate diets than in control rats at room temperature fed on an identical diet. The increase was accompanied by a large accumulation of glycogen in BAT. It was concluded that GS may play an important role in BAT and may contribute to the control of blood glucose in a cold environment. Its relevance to thermogenesis requires further elucidation. 相似文献
97.
A healthy intelligent 13.5-year-old boy is reported who presented with paroxysmal kinesigenic choreoathetosis. He had had unilateral tonic spasms for 2 months. In a stressful situation, especially after a period of immobility, a sudden voluntary movement provoked a dystonic-choreoathetoic posturing of the left arm and leg. Attacks were brought on, for instance, by standing up quickly from a sitting position. They lasted only 5–10 s, without loss of consciousness and occurred up to ten times daily. Between the attacks there were no abnormalities. Family history was non-contributory. Neurological examination and laboratory findings, including repeated EEGs, were all negative. The child responded very well to phenytoin treatment and has now been completely free of dystonic attacks for a period of 9 months. The importance of early recognition of this syndrome and the differential diagnosis with reflex epilepsy and other forms of dystonic choreoathetosis is discussed. 相似文献
98.
Substance P induced histamine release from nasal mucosa of subjects with and without allergic rhinitis 总被引:4,自引:0,他引:4
G. Hanf K. Schierhorn T. Brunnée O. Noga D. Verges G. Kunkel 《Inflammation research》2000,49(10):520-523
OBJECTIVE AND DESIGN: There is evidence that substance P (SP) is involved in events related to allergic and nonallergic rhinitis. Furthermore, some effects of SP seem to be greater in subjects suffering from allergic rhinitis than in nonallergic subjects. To investigate if these effects may be partly mediated by histamine release (HR) we studied the influence of SP on HR from nasal mucosa of subjects with and without allergic rhinitis using an in vitro organ culture system. SUBJECTS: Nasal mucosa of the inferior turbinate was obtained from ten patients suffering from allergic rhinitis and eighteen non-allergic subjects receiving surgical therapy for nasal obstruction. METHODS: Tissue samples of nasal mucosa were stimulated with 10(-5) M SP or with 10(-5) M Ca-ionophore A23187 for 120 minutes, and the histamine content was determined in the culture supernatant. RESULTS: Both SP and Ca-ionophore A23187, caused a significantly higher HR from the samples of the non-allergic group (p < 0.01) compared to baseline controls (spontaneous release). The same effect was seen in the allergic group (p < 0.01 and p = 0.036). Comparing the increase in HR from allergic and non-allergic mucosa, in allergics the HR stimulated by SP was significantly higher (p = 0.031), whereas Ca-ionophore A23187 did not show this effect. CONCLUSION: These findings suggest a role of SP in inducing release of histamine from human nasal mucosa, thereby influencing physiologic and pathophysiologic nasal conditions, especially in allergic inflammatory processes. 相似文献
99.
We demonstrate that a carbohydrate polymer, designated GL402, effectively inhibits epidural fibrosis in a rat laminectomy model. A total laminectomy in Lewis rats was performed at lumbar vertebrae 3 and 5. GL402 or phosphate buffer solutions in gelatin sponges were applied to the laminectomy sites. Epidural fibrosis was measured, using a double-blind protocol, 2 weeks postoperatively either by gross anatomical evaluation (blunt dissection) or by histological evaluation. Local application of GL402 produced nearly complete inhibition of epidural fibrosis, whereas extensive scar formation and bone growth occurred after local application of buffer or other purported anti-fibrotics. In laminectomy sites treated with GL402 the dura mater was essentially free of adhering fibrosis and bone growth was dramatically decreased. With reduction of postlaminectomy fibrosis, the spinal nerve roots are more mobile and therefore may be less prone to recurrent nerve root compression. The dramatic reduction of epidural fibrosis by GL402 will make reoperative disc surgery safer due to greater accessibility of the laminectomy site. This compound may be useful in preventing surgical adhesions in other sites as well. 相似文献
100.