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1.
The Inter-Regional Epidemiological Study of Childhood Cancer (IRESCC) collected interview and medical information relating to the child's past medical experiences from parents of 555 children diagnosed with cancer and parents of 1110 unaffected matched controls. No significant associations emerged overall for ante-natal care, place and mode of delivery, length of gestation, birth weight, condition at birth, special care, neonatal procedures or breast-feeding. Few risk factors relating to previous illnesses and medication were found, although increasing numbers of illnesses appeared to be associated with an increased risk of childhood cancer, particularly acute lymphoblastic leukaemia. A highly significant excess of case children had not been immunised (p = 0.005). In general, these results indicate that past medical experiences have little influence on the development of cancer in children.  相似文献   
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目的 探讨创伤后迟发性脑肿胀的临床特点、发病机制与治疗。方法 回顾性分析1998年1月~2005年6月年收治的17例迟发性脑肿胀患者的临床特点和救治情况。结果 所有颅脑损伤患者采用保守治疗后均有好转,但于伤后5-10d出现恶化,CT复查有脑肿胀,经加强综合脱水等治疗后16例治愈,1例死亡。结论 迟发性脑肿胀好发于对冲性额、颞叶挫裂伤伴明显蛛网膜下腔出血、硬膜下薄层血肿及早期CT有脑肿胀者。其发病机制可能与创伤后的迟发性脑血管痉挛、微循环障碍、静脉回流障碍及甘露醇作用下降等因素有关。此类患者病情隐蔽性强,应加强观察、积极行CT复查,如能早期明确诊断,保守治疗多数效果良好。  相似文献   
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Retrorenal colon: implications for percutaneous diskectomy   总被引:1,自引:0,他引:1  
Helms  CA; Munk  PL; Witt  WS; Davis  GW; Morris  J; Onik  G 《Radiology》1989,171(3):864-865
It has been recommended that computed tomography (CT) with the patient prone be performed in every patient undergoing percutaneous diskectomy; this would enable detection of a retrorenal location of the colon, which could interfere with the percutaneous procedure. In this evaluation of 346 prone CT studies, only one patient (0.29%) was found to have retrorenal or retropsoas bowel that would have been perforated at diskectomy. Because of this extremely low prevalence, the performance of prone CT in every patient undergoing percutaneous lumbar diskectomy is not believed to be necessary.  相似文献   
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The present study has been based on a detailed, computer-assisted, analysis of 112 astrocytomas from patients of all ages seen at The Radcliffe Infirmary between 1938 and 1984. There have been only six studies larger than the present one. From the results obtained in the present study, and the review of the literature, the following conclusions have been reached.Between 70 and 80010 of cerebellar astrocytomas are found in children. Few patients are less than 1 year of age or older than 40 at the time of diagnosis. There appear to be no age peaks. Prognosis is poorest at the extremes of life, children less than 5 years old tending to suffer an early recurrence and patients in the oldest age groups having not only a very rapid recurrence but also a very low overall survival rate.In the present study, there was a slight predominance of males although basically, when all studies are considered, the incidence appears to be equal amongst the sexes. Around puberty there appears to be an abrupt drop in the number of tumours in females and a concomitant rise in the number in males. There appears to be no relationship between sex and the length of survival.It would appear that cerebellar astrocytomas can begin either within the vermis or one hemisphere. There appears to be no laterality, the right and left sides of the cerebellum being affected equally. In the present study, the hemispheres were affected three times more frequently than the vermis (34.807o: 12.5010). The rate of recurrence is much faster with tumours of the vermis, whilst the length of survival to death is much longer with tumours of one hemisphere at least up to 10 years after surgery. The most rapid recurrences take place in tumours which involve both hemispheres and the vermis whilst the poorest survival is associated with tumours infiltrating the brain stem. The average length of history is 18.7 months, being under forty-eight months in approximately 60010 of patients, but only greater than 60 months in 6.201o of cases. The length of history was not related to either patient age or survival time.Most patients present with obstructive hydracephalus with or without localising symptoms. The presentation is usually chronic and intermittent but may also be acute. Symptoms generally appear only after much cerebellar tissue has been destroyed. Clinical features can be divided into four groups: those referrable to raised intracranial pressure; altered cerebellar function; visual disturbance; or cranial nerve dysfunction. Headache was found to be the most common symptom due to raised pressure and it was noted more commonly in the older patients. The rate of recurrence was slower in patients with headache, although their survival to death was not altered. Patients with raised pressure were also commonly noted to be drowsy. Drowsiness was more frequent in children than in adults but not associated with survival. Papillodoema was the most common sign referrable to raised pressure. Although it could not be related to survival, it is essential to relieve raised pressure rapidly in order to preserve vision. A substantial number of patients with large heads were noted in the present study. Ataxia was the most common sign referrable to altered cerebellar function, and found in up to 95°70 of all patients. It was more common in patients with tumours of the vermis than in those of the hemispheres, but was not related to survival. Visual disturbances, including nystagmus, diplopia, and reduced visual acuity, were more common in adults. They could not be related to survival. Cranial nerve palsies were not specifically assessed in the present study. Seventh nerve cranial palsies have been said, however, by others, to be the most reliable, localising sign in patients with cerebellar astrocytomas.  相似文献   
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采用间接ELISA检测23名肾移植受者血清巨细胞病毒(CMV)抗体,共检出18名(78%)活动性CMV感染,其中10名(44%)为原发性感染。结果证实CMV-IgE和-IgA具有较好的血清学诊断价值,优于CMV-IgM。  相似文献   
9.
The beta-amyloid (Abeta) precursor protein (APP) is cleaved sequentially by beta-site of APP-cleaving enzyme (BACE) and gamma-secretase to release the Abeta peptides that accumulate in plaques in Alzheimer's disease (AD). GGA1, a member of the Golgi-localized gamma-ear-containing ARF-binding (GGA) protein family, interacts with BACE and influences its subcellular distribution. We now report that overexpression of GGA1 in cells increased the APP C-terminal fragment resulting from beta-cleavage but surprisingly reduced Abeta. GGA1 confined APP to the Golgi, in which fluorescence resonance energy transfer analyses suggest that the proteins come into close proximity. GGA1 blunted only APP but not notch intracellular domain release. These results suggest that GGA1 prevented APP beta-cleavage products from becoming substrates for gamma-secretase. Direct binding of GGA1 to BACE was not required for these effects, but the integrity of the GAT (GGA1 and TOM) domain of GGA1 was. GGA1 may act as a specific spatial switch influencing APP trafficking and processing, so that APP-GGA1 interactions may have pathophysiological relevance in AD.  相似文献   
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The onset, duration, and offset of pemoline action to improve cognitive performance is examined intensively in 25 prepubescent males suffering from attention-deficit disorder with hyperactivity (ADDH). The purpose was to characterize the pharmacodynamics of pemoline in ADDH patients through correlation of plasma pemoline concentration with psychometric measures of memory search efficiency and paired-associates learning, with the physiological effect of pemoline on dopaminergic transmission concurrently measured by analysis of plasma prolactin response. The effect of pemoline on neuroprocessing is apparent within the first 2 hours after administration with an inverse relationship between plasma pemoline and prolactin concentration present at hour one only (r = 0.84; p = 0.005). Pemoline therapy for 3 weeks does not significantly affect area under the curve for pemoline or prolactin nor did the effect on memory search efficiency decrease, suggesting no apparent tolerance.  相似文献   
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