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91.
OBJECTIVES: We investigated the clinical usefulness of soluble dietary fiber (SDF) for the treatment of diarrhea during enteral nutrition in elderly patients. METHODS: This study included 10 men and 10 women (mean age +/- standard deviation: 79.3 +/- 5.1 y) who had diarrhea during long-term nutrition management. When administering SDF, the initial dose was 7 g and thereafter gradually increased at 1-wk intervals. After 4 wk, the administration was discontinued for 2 wk to confirm the effects of SDF. RESULTS: After the administration of SDF, serum diamine oxidase activity significantly increased (P < 0.001): The water content of the feces decreased significantly after the administration of fiber (P < 0.01). The frequency of daily bowel movements also decreased significantly (P < 0.05). Simultaneously, the fecal features improved. Concerning intestinal flora, there were no significant changes in the total number of bacteria or the number of anaerobic bacteria. The fecal pH decreased significantly 4 wk after the administration of fiber (P < 0.05). The total level of short-chain fatty acids increased significantly 4 wk after the administration of fiber (P < 0.05). There were no significant changes in the various nutritional indices. CONCLUSIONS: The administration of SDF is useful for controlling spontaneous, favorable bowel movement by improving symptoms of small intestinal mucosal atrophy and normalizing the intestinal flora.  相似文献   
92.
Tissue plasminogen activator (tPA) is a serine protease that catalyzes the conversion of plasminogen (plg) to plasmin. The tPA-plasmin system plays a role in synaptic plasticity and remodeling. In this review, we focused on the role of tPA-plasmin system in the rewarding effect of morphine. A single morphine treatment induced tPA mRNA and protein expression in a naloxone-sensitive manner, which was associated with an increase in the enzyme activity in the nucleus accumbens (NAc). The acute effect of morphine in inducing tPA expression was diminished after repeated administration. No differences were observed in the morphine-induced antinociceptive effect between wild-type and tPA knockout (tPA-/-) mice. Morphine-induced conditioned place preference and hyperlocomotion were significantly reduced in tPA-/- and pLg-/- mice, being accompanied by a loss of morphine-induced dopamine release in the NAc. Microinjection of either exogenous tPA or plasmin into the NAc significantly potentiated morphine-induced dopamine release in the NAc of ICR mice. In contrast, plasminogen activator inhibitor-1 (PAI-1) dose-dependently reduced morphine-induced dopamine release. Furthermore, the defect of morphine-induced dopamine release and hyperlocomotion in tPA-/- mice was reversed by microinjections of either exogenous tPA or plasmin into the NAc. Our findings demonstrate a novel function of the tPA-plasmin system in regulating dopamine release in the NAc, which is involved in the morphine reward.  相似文献   
93.
The efficacy of a new cervico-thoracic Neck-Chest brace (N-C brace) prepared for post- operative patients of cervical canal expansive laminoplasty was assessed. The orthosis is light in weight (300 g) and easy to fit. The effect of the orthosis to restrict the neck motion was studied in 10 normal young males by using lateral view radiographs in extension and flexion positions. The average range of the neck motion for the N-C brace was 24.4% of the values obtained without the orthosis. The restriction of the motion was significantly better than that without orthosis. Then, the clinical efficacy of the N-C brace was assessed in 40 patients of cervical spondylotic myelopathy who underwent expansive laminoplasty. Alignment changes of the postoperative cervical spine was found only in 10% of the patients who had a straight and kyphotic curvature pattern in the cervical spine before operation. The cervical alignments in the other 90% of patients were not changed post-operatively. These data clearly demonstrated that the N-C brace effectively controls the neck motion and is recommended for patients who have a lordotic curvature pattern in the cervical spine to prevent the post-surgical changes in the alignment after expansive laminoplasty.  相似文献   
94.
(Received for publication on Feb. 10, 1999; accepted on Nov. 11, 1999)  相似文献   
95.
Summary A large dose of 24R,25(OH)2D3 was administered to the vitamin D-repleted rat to examine its effect on the bone. Male Wistar rats were fed a diet containing 0, 0.025, 1.25, 4.0, and 12.5 ppm 24R,25(OH)2D3 for 2 years starting at age 6 weeks. The estimated amounts of daily intake of 24R,25(OH)2D3 were 0, 93, 4640, 14680, and 49580 ng/100 g body weight, respectively. No notable difference was found in either the weight or the death rate of the animal. The long-term administration of massive doses of 24R,25(OH)2D3 did not lead to hypercalcemia nor did it affect the blood phosphorus, alkaline-phosphatase, or creatinine levels. Radiographs revealed a striking increase in the bone density on the bones from the animals treated with 1.25 ppm or more 24R,25(OH)2D3. Direct single photon absorptiometry revealed a dose-dependent increase in total bone minerals of both the femur and coccyx. Histological examination revealed a marked increase in the cortical thickness of the femur as well as in the cancellous bone volume of the coccyx. Polarizing microscopy demonstrated the lamellar structure of the bone, and undecalcified sections confirmed the increase of mineralized bone. Ash weight, calcium, phosphorus, and magnesium contents on the tibia and fibula also indicated the ascending dose-dependent increase up to 150% of the control. The parameters of bone size were not altered in any group. These results clearly suggest that 24R,25(OH)2D3 given in massive doses has the pharmacological action of increasing bone volume in the rat without causing remarkable hypercalcemia.  相似文献   
96.
To investigate the auditory impairment induced by the administration of aminoglycosides in the newborn, the shuttle box method was employed to measure the auditory threshold of rats. Five groups of newborn rats were administered kanamycin sulfate, 250 and 500 mg/kg, streptomycin sulfate, 250 and 500 mg/kg, or 1 ml/kg saline, subcutaneously, from the 10th to the 15th day of birth. The auditory threshold of the control group could be measured by the shuttle box method at the age of 100 days. The auditory threshold of the control group was 52.1 +/- 1.0 dB (N = 14). The auditory thresholds of the animals treated with kanamycin 250 mg/kg and streptomycin 250 mg/kg groups were measured in only 1 (61.0 dB) and 4 (64.8 +/- 4.6 dB), respectively, since the auditory toxicity of these drugs in newborn rats was stronger than adult rats. Auditory threshold of the 250 mg/kg streptomycin group was significantly higher than that of the control group. The animals which could not be measured for the auditory threshold had the ability to acquire conditioned avoidance response when both conditioned stimuli (tone and light) were presented. However, after differentiation of the stimuli, the percent avoidance to tone in these animals was significantly decreased and did not recover by the following trainings, while the percent avoidance to light was similar to that before the differentiation.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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99.
Accumulating evidence indicates that growth hormone (GH) might be effective at preventing the development of Alzheimer's disease. However, exogenous GH treatment has exhibited side effects for clinical application; thus supplementation with amino acids to promote the release of GH could be a possible alternative treatment. In this study, mice that were fed with a diet of GH-releasing supplements had significantly attenuated memory impairments and hippocampal changes in the acetylcholinesterase activity and acetylcholine level induced by amyloid beta protein (Abeta) (1 - 42). Our results suggest that the use of GH-releasing supplement exerts beneficial effects on the memory impairment induced by Abeta (1 - 42).  相似文献   
100.
We studied the effect of pre-injury magnesium (Mg(2+)) treatment on hippocampal extracellular signal- regulated kinase (ERK) activation induced by lateral fluid-percussion (FP) brain injury, and on working and reference memory in the radial-arm maze test in rats subjected to such traumatic brain injury (TBI) (n = 56) or to sham injury (n = 12). In the ipsilateral hippocampus, an increase in the phospho-ERK level was detected at 10 min after injury in rats subjected to FP brain injury of moderate severity (1.9-2.0 atm) as compared to sham-injured controls (p < 0.01), and was maintained for at least 120 min after injury (p < 0.05). In the contralateral hippocampus, the phospho-ERK level was transiently increased at 10 min after injury but fell to nearly its basal level by 30 min. When MgCl(2) solution (150 micromol) was infused intravenously from 20 min to 5 min before injury (n = 4-5), brain injury-induced ERK activation was significantly inhibited in the ipsilateral hippocampus at 60 min but not at 10 min after injury. Mg(2+) treatment also significantly prevented injury- induced neuronal loss in the ipsilateral hippocampus (p < 0.05 vs. vehicle-treated, brain-injured controls). At 2 weeks after injury, Mg2+ treatment was found to have significantly prevented injury-induced impairments in working (p < 0.0001 vs. vehicle-treated, brain-injured controls) and reference memory (p < 0.05) in the radial-arm maze test. The present study demonstrates that pretreatment with Mg(2+) prevents post-traumatic hippocampal ERK activation and neuronal loss, and cognitive dysfunction in the radial-arm maze test.  相似文献   
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