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151.
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153.
Mesquita F Aguiar JF Oliveira JA Garcia-Cairasco N Varanda WA 《Brain research bulletin》2005,65(2):177-183
The main goal of this work was to analyze the electrophysiological properties of cultured hippocampal neurons from a particular epileptic rat strain, called Wistar Audiogenic Rats (WAR). The whole-cell patch-clamp technique was used to record both active and passive membrane responses in an attempt to detect alterations in their characteristics in relation to controls from Wistar rats. Neurons from WARs show a significant reduction in the magnitude of the inhibitory GABAergic currents ( approximately 45%), in spite of maintaining a normal level of the excitatory glutamatergic currents. In addition, the magnitude of potassium currents, measured at +80 mV, is reduced by about 30% in comparison to controls. Surprisingly, we also found important changes in the passive cellular properties in WAR neurons such as membrane potential (-50.0 mV in WARs and -63.1 mV in controls) and input resistance (647 MOmega in WARs and 408 MOmega in controls). The changes described here, could be the basis of the neurophysiological and behavioral alterations present in these hyperexcitable animals, contributing to a better understanding of epileptogenesis in this particular animal model. 相似文献
154.
Ferreira JE de Mello PA de Magalhães AV Botelho CH Naves LA Nosé V Schmitt F 《Arquivos de neuro-psiquiatria》2005,63(4):1070-1078
Clinically non-functioning pituitary adenomas do not produce clinical signs of hormonal hypersecretion. Therefore, signs and symptoms will depend on the mass effect of these adenomas over the central nervous system. Their etiopathogeny is complex and their development is probably influenced by several factors, such as hypothalamic hormones (GHRH), growth factors (FGF), proliferation factors (PCNA, and KI-67), protein P53 and the proto-oncogene c-erb-B2. OBJECTIVE: 1) Determining the clinical features of a population of 117 patients treated for clinically non-functioning pituitary adenoma (age, sex, tumor size, number of surgical procedures, development of hormonal deficiency and hyperprolactinemia). 2) Identifying, after the patients had been clinically characterized, those with clinically non-functioning adenomas with positive immunohistochemistry for hypophyseal hormones (PRL, LH, FSH, GH, TSH and ACTH). 3) Determining if the immunohistochemistry of this population was positive for the cellular proliferation factor Ki-67, protein P53 and protein C-erb-B2 and establishing a correlation with tumor size and tumor invasiveness. This will help in the evaluation of the prognostic value of these proliferation factors. 4) Confronting the results of immunohistochemistry using a standard block with the results of immunohistochemistry using a tissue micro-array. METHOD: Study of the clinical features of 117 patients with clinically non-functioning pituitary adenoma (age, sex, tumor size, number of surgical procedures, development of hormonal deficiency and hyperprolactinemia). Immunohistochemical study (H&E) of 39 patients for hypophyseal hormones, protein P53, protein C-erb-B2, Ki-67 to establish their correlation to tumor growth. The next step was a tissue micro-array of the 39 previously studied cases, using immunohistochemistry for hypophyseal hormones, protein P 53, protein C-erb-B2, Ki-67 to establish their correlation to tumor growth. RESULTS: There was no statistically significant difference between males and females with regards to age, tumor size and number of surgical procedures (p=0.279, p=813, p=139 respectively). There is a statistically significant correlation between the size of the tumor, the number of surgical procedures and hormonal deficiency (p=0.032, p=0.223 respectively). There was no statistically significant correlation between a positive immunohistochemistry for protein P53, protein C-erb-B2, Ki-67 and tumor size (r=0.182, p=0.396; r=-0.181, p=0.397; r=0.272, p=0.199, respectively). The tissue micro-array also did not demonstrate a correlation between positive immunohistochemistry for Ki-67 and C-erb-B2 and tumor size, but it showed a statistically significant correlation between a positive immunohistochemistry for p53 and tumor size (r=-0.696; p=001). CONCLUSION: The biological behavior of the clinically non-functioning adenoma is similar for both sexes. The larger the tumor the greater the number of surgical procedures needed. Hormonal deficiency also becomes more significant as the size of the tumor increases. This paper suggests that a positive immunohistochemistry for p53 is negatively correlated to tumor size, thus demonstrating that it has a predictor value. However, a positive immunohistochemistry for Ki-67 and protein C-erb-B2 does not seem to be a prognostic factor for clinically non-functioning pituitary adenomas, as is the case with other neoplasias. 相似文献
155.
Falbo G Caminha F Aguiar F Albuquerque J de Chacon Lourdes M Miranda S Marques S 《Journal of tropical pediatrics》2004,50(5):292-296
The intergenerational transmission of violence and the tendency for abused and neglected children to become abusers, delinquents, and violent offenders in their adult life is an important field to be understood. It is also important to understand these backgrounds to guide future preventative interventions. Through a cross-sectional study, the occurrence of abuse during childhood and adolescence of adult women incarcerated in a female state prison at Recife in northeast Brazil was investigated. Among 219 prisoners, 190 accepted to join the research; 149 were young women (23-27 years) with severe educational deficiency. Living in poor socioeconomical conditions with problematic and violent familiar relations, 116 (61 per cent) left home at the end of their adolescence and the same number reported having been abused (p < 0.000015). There was a statistical significance between the abuses suffered and witnessed by the subjects and the perpetration of abuse against children and adolescents by themselves (p < 0.0022 and p < 0.0000049). Parents were the most frequent perpetrators (37.4 per cent). Sexual activity and use of legal and illegal drugs occurred early in adolescence. The group also had a family history of violence. Based on the analysed data of this studied group, the authors assumed that the abuse suffered in childhood and adolescence of these women drove them to be abusers in adult life and could have been a predictive marker for their conduct disorders and subsequent criminal behavior. 相似文献
156.
Ventral cardiac denervation reduces the incidence of atrial fibrillation after coronary artery bypass grafting 总被引:5,自引:0,他引:5
Melo J Voigt P Sonmez B Ferreira M Abecasis M Rebocho M Timóteo A Aguiar C Tansal S Arbatli H Dion R 《The Journal of thoracic and cardiovascular surgery》2004,127(2):511-516
OBJECTIVES: Because the autonomic nervous system is an important determinant in the appearance of atrial fibrillation, we have assessed the role of ventral cardiac denervation for its prevention. METHODS: Patients undergoing low-risk coronary artery surgery were enrolled. No routine antiarrhythmic drugs were administered before or after the operation. Ventral cardiac denervation was performed in 207 patients, and 219 patients were used as control subjects. Denervation was performed before cardiopulmonary bypass. The groups were comparable regarding demographic, clinical, and operative variables. RESULTS: The additional time for the denervation was 5 +/- 2 minutes, and there were no associated complications. Postoperative atrial fibrillation was present in 15 (7%) patients undergoing ventral cardiac denervation (95% confidence interval, 4%-12%) and in 56 (27%) control subjects (95% confidence interval, 18%-35%). Patients submitted to ventral cardiac denervation had fewer and less severe episodes of atrial fibrillation, and no patient had atrial fibrillation after discharge. Ventral cardiac denervation was the most significant predictor of postoperative atrial fibrillation (odds ratio, 0.42; confidence interval, 0.23-0.78; P =.006). Age of greater than 65 years (odds ratio, 1.67; confidence interval, 0.96-2.9; P =.067) was a highly suggestive predictor. The analysis of the effect of ventral cardiac denervation correlated with the patient's age showed a more pronounced effect in patients younger than 70 years (odds ratio, 0.43; confidence interval, 0.22-0.86; P =.022) CONCLUSIONS: Ventral cardiac denervation is a fast and low-risk procedure. Its use significantly reduces the incidence and severity of atrial fibrillation after routine coronary artery bypass surgery. Patients younger than 70 years of age are expected to have a higher success rate than those older than 70 years. 相似文献
157.
Simultaneous pancreas-kidney transplantation: infectious complications and microbiological aspects 总被引:8,自引:0,他引:8
Linhares MM Gonzalez AM Triviño T Barbosa MM Schraibman V Melaragno C Moura RM Silva MH Sá JR Aguiar WF Rangel EB Serra CB Succi T Pestana JO 《Transplantation proceedings》2004,36(4):980-981
OBJECTIVE: The purpose of this study was to describe the clinical and microbiological characteristics of the infectious complications among simultaneous pancreas-kidney transplantations (SPKT). MATERIALS AND METHODS: Among the first 45 SPKT the mean age was 34 years (range, 21 to 49) and the mean duration of follow-up 13 months (range, 2 to 27 months). RESULTS: Twenty-three patients (51%) presented at least one to three episodes (1.7 mean) of infectious complications that needed hospitalization. The etiology of the infections included 71% bacterial (44% gram-negative rods and 27% gram-positive cocci), 16% viral (12% from CMV and 4% from Herpes sp) and 13% fungal (8% by Candida sp and 4% by others fungus). Wound and urinary infections were most frequent, occurring in 22% and 28% of the patients, respectively. All patients who were submitted to vesical drainage developed infections in contrast a rate of only 44% among patients undergoing enteric drainage. CONCLUSION: Infectious complications are the main cause of morbidity and mortality following simultaneous pancreas-kidney transplantation, especially with vesical drainage. The use of enteric drainage combined with administration of broad spectrum prophylactic antibiotics is recommended. 相似文献
158.
159.
The neotropical freshwater fish matrinx?, Brycon cephalus (Günther, 1869), was exposed to 1/3 of 96 h-LC50 of Folidol 600 (methyl parathion) for 96 h and allowed to recover for 24, 48, 96, and 192 h. Acetylcholinesterase (AChE), alanine aminotransferase (ALAT), aspartate aminotransferase (AAT), lactate dehydrogenase (LDH), malate dehydrogenase (MDH), and glutamate dehydrogenase (GDH) were assayed in brain, liver, muscle, and plasma. Plasma and brain AChE activities were strongly inhibited (64% and 87%, respectively), remaining low in the brain during recovery. Liver ALAT decreased 59.4% and plasma ALAT increased 94.2%. This response, associated with GDH reduction during the recovery period, was attributed to impairment of amino acid metabolism and to liver damage. The increase of heart and plasma AAT suggested tissue injury. Liver and plasma LDH and MDH did not change during the exposure to Folidol, but liver MDH decreased 34% during recovery, indicating a failure of oxidative metabolism in such tissue. Hepatic glycogen and glucose levels decreased 80.4 and 55%, respectively, followed by glucose mobilization to the plasma. The hepatic and muscular profile of lactate after recovery suggested gluconeogenesis without tissue hypoxia. These results revealed that methyl parathion affects the intermediary metabolism of matrinx? and that the assayed enzymes can work as good biomarkers of organophosphorus pesticide contamination. 相似文献
160.
Sotelo Yde O Colugnati FA Taddei JA 《Cadernos de saúde pública / Ministério da Saúde, Funda??o Oswaldo Cruz, Escola Nacional de Saúde Pública》2004,20(1):233-240
To compare the prevalence of child obesity according to three criteria, a cross-sectional study was performed with 6-to-11-year-old children in eight elementary public schools in the city of S?o Paulo. Z scores for weight-for-height (W/H) and body mass index (BMI) were calculated from the weight and height variables. Prevalence rates for overweight in males, according to Must, Cole, and WHO criteria, were 10.92%, 10.29%, and 11.94%, respectively, and for obesity 8.17%, 13.67%, and 10.29%. For females, prevalence rates for overweight according to Must, Cole, and WHO criteria were 13.51%, 13.83%, and 13.67%, respectively, and for obesity 8.25%, 16.50%, and 11.73%. The study analyzes the variations in obesity estimates based on different criteria, highlighting the need for clinical and population studies to support the development of a single criterion. Such studies, in addition to identifying individuals with a higher probability of excess body fat, could also correlate body fat to risk of illness and death (similar to the 25 and 30 BMI cutoff points in adults). 相似文献