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991.
A similar pattern of deficits in executive function and neuroanatomical abnormalities is shared between 22q 11.2 deletion syndrome (22q 11DS) and schizophrenia, suggesting that common cerebral alterations may lead to cognitive dysfunction and promote the appearance of psychotic symptoms in 22q 11DS individuals. Specifically, there is increasing evidence for involvement of the cingulate gyrus (CG) in executive dysfunction and the expression of positive symptoms in schizophrenia. The aim of our study is to examine CG morphology in a 22q 11DS population and its potential role as a cerebral marker of executive dysfunction and the manifestation of psychotic symptoms. Using region of interest (ROI)-based analysis, we compared CG volumes from 58 children and adults affected by 22q 11DS with 64 healthy age- and gender-matched controls. After covarying for total cranium grey matter and age, a bilateral reduced CG grey matter volume, driven by a decrease in anterior CG cortex, was observed among 22q 11DS patients. Further post hoc analyses suggest correlations between right CG cortical reductions, low-executive functioning and the occurrence of psychotic symptoms. The CG structural abnormalities observed in 22q 11DS are consistent with previous reports in schizophrenic patients and are associated with pre-morbid cognitive impairments. The mechanisms by which these changes may modulate executive functioning and the expression of psychosis are discussed. 相似文献
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Wahed M Geoghegan M Powell-Tuck J 《European journal of gastroenterology & hepatology》2007,19(5):365-370
Enteral and parenteral feeds need at least to contain adequate amounts of water, energy, protein, electrolytes, vitamins and trace elements. Ready-manufactured parenteral feeds for example are incomplete because of shelf-life constraints and require the addition of vitamins (especially) and trace elements. Acute vitamin deficiencies, notably thiamine deficiency, can be precipitated if this is not adhered to. An increasing interest, however, exists in the use of feeds containing substrates, which are intended to improve patient outcome in particular clinical circumstances. The purpose of this article is to examine as to what is available and make recommendations on their use. It deals with artificial feeds only - disease-specific diets are outside our remit. 相似文献
996.
X-linked adrenoleukodystrophy (X-ALD) is caused by a defect in the gene ABCD1, which maps to Xq28 and codes for a peroxisomal membrane protein that is a member of the ATP-binding cassette transporter superfamily. X-ALD is panethnic and affects approximately 1:20,000 males. Phenotypes include the rapidly progressive childhood, adolescent, and adult cerebral forms; adrenomyeloneuropathy, which presents as slowly progressive paraparesis in adults; and Addison disease without neurologic manifestations. These phenotypes are frequently misdiagnosed, respectively, as attention-deficit hyperactivity disorder (ADHD), multiple sclerosis, or idiopathic Addison disease. Approximately 50% of female carriers develop a spastic paraparesis secondary to myelopathic changes similar to adrenomyeloneuropathy. Assays of very long chain fatty acids in plasma, cultured chorion villus cells and amniocytes, and mutation analysis permit presymptomatic and prenatal diagnosis, as well as carrier identification. The timely use of these assays is essential for genetic counseling and therapy. Early diagnosis and treatment can prevent overt Addison disease, and significantly reduce the frequency of the severe childhood cerebral phenotype. A promising new method for mass newborn screening has been developed, the implementation of which will have a profound effect on the diagnosis and therapy of X-ALD. 相似文献
997.
Ashrafi MR Shabanian R Abbaskhanian A Nasirian A Ghofrani M Mohammadi M Zamani GR Kayhanidoost Z Ebrahimi S Pourpak Z 《Pediatric neurology》2007,36(1):25-29
Oxidative stress and generation of reactive oxygen species are strongly implicated in a number of neuronal and neuromuscular disorders, including epilepsy. The functions of selenium as an antioxidant trace element are believed to be carried out by selenoproteins that possess antioxidant activities and the ability to promote neuronal cell survival. Because of this protective role of selenium against oxidative damage, a case-control study was designed to compare its serum level between intractable epileptic patients and normal subjects. Eighty patients who met the criteria of intractable epilepsy were compared with a normal control group of the same age, socioeconomic level, and place of living. Serum selenium level was measured with an atomic absorption spectrophotometer. The mean (+/- S.D.) of serum selenium were 68.88 (+/-17.58) ng/mL and 85.93 (+/-13.93) ng/mL in the patient and control groups respectively. Independent sample t test with P < 0.05 indicated a significant lower mean of serum selenium in the patient group compared with that of the normal control group. However, there was no association between serum selenium and some suggested predictive factors of intractable seizures, including age at the onset of seizures, neonatal seizure, neurologic impairment, and etiology of epilepsy. Measurement of serum selenium in patients with intractable epilepsy should be considered. 相似文献
998.
BACKGROUND: Favourable outcomes have been reported for patients with childhood cerebral adrenoleukodystrophy (CCALD) who had received haematopoietic cell transplantation (HCT) at the early stage of cerebral involvement. However, comparative data for non-transplanted CCALD patients are limited. We analysed survival of CCALD patients who had not received HCT and, in a subgroup with early cerebral disease, compared survival in those who underwent HCT with those who did not. METHODS: Retrospective survival analyses were done on 283 CCALD patients identified at the Kennedy Krieger Institute who had not received HCT, focusing on a 30-member early stage cerebral subgroup whose neurological disability and MRI severity scores matched those in a 19-member transplanted subgroup previously reported. A Kaplan-Meier survival curve and log-rank test were used for survival analysis and to estimate the difference between the survival probabilities of the groups with statistical significance set at alpha=0.05. FINDINGS: Mean age at onset of symptoms in the entire 283 non-transplanted group was 7 years (SD 2 years). 131 (46%) patients died during the mean follow-up period of 5.9 years (5.3) at a mean age of 12.3 years (4.9). 5-year survival was 66%. The 5-year survival probability of 54% in the early stage group was significantly poorer (chi(2)=7.47, p=0.006) than the 5-year survival of 95% in the transplanted group with early stage cerebral disease. INTERPRETATION: HCT done in the early and progressive stages of CCALD is beneficial, and our data support the recommendation that transplantation be offered to patients in the early stages of CCALD. 相似文献
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Nadji SA Mahmoodi M Ziaee AA Naghshvar F Torabizadeh J Yahyapour Y Nategh R Mokhtari-Azad T 《Lung cancer (Amsterdam, Netherlands)》2007,56(2):145-151
The TP53 gene has a polymorphism in exon 4 at codon 72 that presents the arginine or proline genotype. The association of TP53 codon 72 polymorphism with lung cancer risk has been studied by several groups, although with inconsistent results. Our previous study showed that the human papillomavirus (HPV) infection is associated with the development of lung cancer in Mazandaran, north part of Iran (cases=25.6% versus controls=9.0%, P=0.002). The frequency of TP53 codon 72 polymorphism was studied in a north part Iranian group of 92 healthy controls and 141 lung cancer patients. The allelic distribution of the three genotypes (ArgArg, ArgPro, ProPro) in healthy normal controls was 46.1, 32.6 and 21.3%, respectively, which differs from that of lung cancer patients showing genotype frequency as 42.6, 49.6 and 7.8%. A relation between the presence of the Arg allele and lung cancer risk was observed. Our study reveals that Arg allele, active smoking and HPV infection are the important risk factors in lung cancer development in the north part of Iran, Mazandaran province. 相似文献