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991.
OBJECTIVE: To investigate changes in plasma interleukin (IL)-6, cortisol or noradrenaline concentrations after surgery in elderly patients with postoperative confusion. METHODS: We studied 80 patients aged 70-90 years undergoing abdominal surgery and measured plasma IL-6, cortisol or noradrenaline concentrations before surgery, at the end of surgery, and 24 and 48 h after surgery. RESULTS: Plasma IL-6 concentrations in elderly patients with postoperative confusion were 83.2 +/- 30.5, 49.3 +/- 14.1 and 42.9 +/- 19.4 pg.ml(-1) at the end of surgery, and 24 and 48 h after surgery, respectively, being significantly higher than in elderly patients without postoperative confusion (58.0 +/- 37.5, 36.1 +/- 20.0 and 28.2 +/- 16.7 pg.ml(-1)). Plasma cortisol concentrations in elderly patients with postoperative confusion (42.2 +/- 7.8, 38.3 +/- 8.3 and 33.1 +/- 8.4 microg.dl(-1) at the end of surgery, and 24 and 48 h after surgery, respectively) were significantly higher than in elderly patients without postoperative confusion (32.9 +/- 6.7, 30.4 +/- 8.6 and 25.6 +/- 6.5 microg.dl(-1), respectively). There were no significant differences in plasma norepinephrine concentrations at all sampling points between elderly patients with and without postoperative confusion. However, plasma IL-6 and cortisol concentrations were related in elderly patients with postoperative confusion (at the end of surgery and 24 and 48 h after surgery). However, there was no relationship between plasma IL-6 and cortisol concentrations 24 and 48 h after surgery in elderly patients without postoperative confusion. CONCLUSION: Elderly patients with postoperative confusion had increased plasma IL-6 and cortisol concentrations. The interaction between IL-6 and cortisol after surgery is associated with developing postoperative confusion in the elderly patients.  相似文献   
992.
To estimate the effects of changes in body posture on sudomotor function, sweat rates on the forearm, chest and thigh, tympanic temperature (Tty), and skin temperatures were recorded in an upright sitting and a supine position under a hot environment of 40 degrees C Ta and 40% relative humidity for 60 min. Sweat expulsions were identified on sweat rate curves and their rates (Fsw) were calculated. Tty was higher, and its initial fall was greater, in the supine position than in the sitting position. On the forearm and the chest, the regression line relating sweat rate to mean body temperature (Tmb) had a gentler slope in the supine position, whereas on the thigh, it showed a steeper slope. The regression line relating Fsw to Tmb had a steeper slope in the supine position than in the sitting position, suggesting that the gain in the mechanisms for central integration and rhythm-generation was enhanced in the supine position. The parameter of sweat rate divided by Fsw was lower on the forearm and the chest, whereas it was higher on the thigh in the supine position than in the sitting position, suggesting that sudomotor outflow was modified at the spinal cord in association with skin pressure. It was concluded that body posture affects sudomotor functions through both brain and spinal mechanisms.  相似文献   
993.
Sclerosing mediastinitis is a very rare benign disorder characterised by the development of dense fibrous tissue within the mediastinum. Affected patients are typically young adults with infant cases being uncommon especially in areas without endemic histoplasmosis. We report a Japanese boy with markedly elevated serum inflammatory markers for more than 1 year in the absence of any clinical manifestations. 67Ga-scintigraphy demonstrated an accumulation in the mediastinal region and an open biopsy revealed a hard fibrous mass in the anteriosuperior mediastinum. Thus, a diagnosis of idiopathic sclerosing mediastinitis was made. Conclusion:To the best of our knowledge, this case is the youngest patient reported with this disorder. In patients with mediastinal mass lesions the diagnosis of sclerosing mediastinitis should be considered as well as infectious, autoimmune or neoplastic disease even in children.  相似文献   
994.
OBJECTIVES: We previously reported the presence of periportal hypodensity on CT image in two newborns and an early infant with congenital tuberculosis as an adjunct diagnostic option. The aim of this study was to determine the degree of treatment based on both periportal hypodensity and serum IgM presented in asymptomatic newborns born from tuberculosis mothers. SUBJECTS AND METHODS: Eight newborns born from mothers with untreated tuberculosis between 1996 and 2002 were retrospectively studied. Newborns who presented periportal hypodensity and high serum IgM were treated with anti-tuberculosis medicines, combination of isoniazid and rifampicin for nine to 12 months with streptomycin in the initial two months, and the outcomes of the treatment were followed for at least two years. RESULTS: All eight newborns had gastric aspirates negative for Mycobacterium tuberculosis. Three of eight newborns (38%) demonstrated periportal hypodensity, and they also demonstrate a tendency of high serum IgM. None of these three newborns treated with combination of isoniazid, rifampin, and streptomycin for 9 to 12 months developed tuberculosis during the observation period. CONCLUSIONS: These results suggest that presence of both periportal hypodensity and high serum IgM in asymptomatic newborns born from mothers with untreated tuberculosis may be one of risk factors of developing congenital tuberculosis, and that anti-tuberculosis treatment for nine to 12 months may prevent them from the disease development despite possible criticism of overdiagnosis and overtreatment.  相似文献   
995.
In the early development of the central nervous system, neural progenitor cells divide in an asymmetric manner and migrate along the radial glia cells. The radial migration is an important process for the proper lamination of the cerebral cortex. Recently, a new mode of the radial migration was found at the intermediate zone where the neural progenitor cells become multipolar and reduce the migration rate. However, the regulatory signals for the radial migration are unknown. Using the migration assay in vitro, we examined how neural progenitor cell migration is regulated. Neural progenitor cells derived from embryonic mouse telencephalon migrated on laminin-coated dishes. Endothelin (ET)-1 inhibited the neural progenitor cell migration. This ET-1 effect was blocked by BQ788, a specific inhibitor of the ETB receptor, and by the expression of a carboxyl-terminal peptide of Galpha q but not Galpha i. The expression of constitutively active mutant of Galpha q, Galpha qR183C, inhibited the migration of neural progenitor cells. Moreover, the inhibitory effect of ET-1 was suppressed by the c-Jun N-terminal kinase (JNK) inhibitor SP600125 and the expression of the JNK-binding domain of JNK-interacting protein-1, a specific inhibitor of the JNK pathway. Using the slice culture system of embryonic brain, we demonstrated that ET-1 and the constitutively active mutant of Galpha q caused the retention of the neural progenitor cells in the intermediate zone and JNK-binding domain of JNK-interacting protein-1 abrogated the effect of ET-1. These results indicated that G protein-coupled receptor signaling negatively regulates neural progenitor cell migration through Gq and JNK.  相似文献   
996.
Our previous study indicated that taste information via the chorda tympani (CT) activates the central histaminergic system in anesthetized rats. However, the physiological roles of taste-induced histamine release remain unknown, thus to further investigate the relationship between histamine release and gustatory information, in the present study we investigated the effect of taste stimuli infused intraorally on histamine release using in vivo microdialysis in free moving rats. Consistent with findings from our previous study, application of NaCl and HCl caused significant increases in histamine levels further supporting the suggestion that this phenomenon is attributed to the excitation of the CT. When rats were intraorally infused with quinine HCl (QHCl) solution, a significant increase in hypothalamic histamine release was observed. On the other hand, histamine release was decreased by sucrose and saccharin solutions. When rats were conditioned to acquire taste aversion to sucrose solution or saccharin solution, instead of the histamine decrease seen by the palatable solutions, the pattern of histamine release was similar to that seen by QHCl solution. From these observations, it is concluded that the histamine release by the infusion of these tastants may be explained by two mechanisms-by causing a transient increase after taste stimulation and by causing a decrease relative to the tastant's palatability.  相似文献   
997.
Background One of the cardinal features in multiple system atrophy (MSA) is the white matter pathology: loss of myelin, astrocytosis, and glial cytoplasmic inclusions. The pathological changes of tissue microstructure can modify the diffusion behavior of water molecules, which can be assessed by diffusion tensor imaging (DTI). Objectives To explore the hypothesis of white matter degeneration in MSA. Methods We studied 11 patients with clinically probable MSA and 10 age–matched controls. DTI was performed in both groups to measure fractional anisotropy (FA) in various regions of interest: the inferior cerebellar peduncle (ICP), middle cerebellar peduncle (MCP), superior cerebellar peduncle (SCP), basis pontis, internal capsule, and corpus callosum. Results FA values in SCP and corpus callosum showed no significant difference between the MSA group and controls. By contrast, FA values decreased in the MSA group in the MCP, basis pontis and internal capsule. In addition, FA values in the MCP were negatively correlated with ataxia severity in the MSA group. Conclusion The areas showing decreased tissue anisotropy in DTI corresponded well with pathologically vulnerable areas in MSA. In addition, the local tissue anisotropy of MCP decreased in accordance with functional disability. These observations implied that DTI is a feasible method for in vivo evaluation of the white matter pathology in MSA.This work was supported by funds from the Japanese Ministry of Education, Science and Technology (Grant number 14770295).  相似文献   
998.
999.
We report a case of dermatophytosis in a Judo wrestler caused by Trichophyton tonsurans (T. tonsurans) with clinical features that mimicked the concentric rings of tinea imbricata. Tinea imbricata is a unique dermatophytosis caused by Trichophyton concentricum (T. concentricum), observed endemically in subtropical to torrid zones and characterized by impressive concentric rings. We found three similar cases of the dermatophytosis in the literature that were reported as tinea pseudoimbricata or tinea indecisiva. All of these cases were associated with systemic or local immunosuppression, perhaps simulating the mechanism of tinea imbricata, which is known to involve the lack of delayed type hypersensitivity to T. concentricum. These cases imply that iatrogenic immunosuppression may perhaps play an important role in the development of the unique clinical features mimicking tinea imbricata. Furthermore, three of the four cases, including the presented case, were caused by T. tonsurans. It may be necessary to consider T. tonsurans infection when multiple concentric erythemas are encountered.  相似文献   
1000.
Most children who go through adolescence manage to overcome the "storm of adolescence," but some children are not so fortunate and have difficulty in coping. They may feel that their inability to cope is unique or that they will forever be handicapped or diseased as a result. In reality, the trials of adolescence, combined with a sub optimal personal life often result in setbacks. Adolescence, by definition is a time of development. And this development is extensive; physical, mental, sexual and self-awareness. Personality change is inevitable. Over a relatively short period, young children evolve into adults. Every one experiences these drastic changes, but to each child, it seems that he/she is going through the experience alone, for the first time. We must convey to these children that this situation is normal, and is inevitably stressful. If we can succeed in even a small way to do this, I believe we can find a way to help adolescent children.  相似文献   
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