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991.
Jeroen Hoogland MsC Rob M.A. de Bie MD PhD Caroline H. Williams‐Gray MRCP PhD Dino Muslimović PhD Ben Schmand PhD Bart Post MD PhD 《Movement disorders》2010,25(15):2550-2554
Cognitive dysfunction is one of the most incapacitating non‐motor symptoms of Parkinson's disease (PD). Some cognitive deficits are thought to be related to abnormal dopamine homeostasis. The latter is influenced by catechol‐O‐methyltransferase (COMT), an enzyme that degrades dopamine. Previous research suggests a relationship between the COMT val158met functional polymorphism (SNP) and measures of executive function. We evaluated this hypothesis in a cohort of PD patients with an extensive neuropsychological test battery. Cognitive assessment and COMT genotyping were performed in 153 early PD patients from outpatient clinics general hospitals in the Netherlands. Our results do not support a direct effect of COMT val158met genotype on performance on neuropsychological measures of attention and executive function, but they suggest that genotype may interact with dopaminergic medication use to influence cognitive ability. © 2010 Movement Disorder Society 相似文献
992.
Nataša Jovanov‐Milošević Zdravko Petanjek Davor Petrović Miloš Judaš Ivica Kostović 《The European journal of neuroscience》2010,32(9):1423-1432
The aim of this study was to investigate the morphology, molecular phenotypes, distribution and developmental history of interstitial neurons in the human corpus callosum, here defined as intracallosal neurons. We analysed 26 fetuses, three newborns, five infants and children, and eight adults [age range – 15 weeks postconception (PCW) to 59 years] by means of acetylcholinesterase (AChE) histochemistry and immunohistochemistry for neuron markers (MAP2, NeuN, NPY, calretinin and calbindin). We found a heterogeneous neuron population, positioned within the callosal trunk itself (aside from neurons present in the transient midline structures such as callosal sling, septa or subcallosal zone), which was most numerous during the second half of gestation and early postnatal years. We named these cells intracallosal neurons. At 15 PCW, the intracallosal neuron population consisted of poorly differentiated, small fusiform or bipolar, migratory‐like MAP2‐ or calretinin‐positive neurons which could be observed until mid‐gestation. Later the population comprised morphologically diverse, predominantly well‐differentiated MAP2‐, NPY‐, calbindin‐ and AChE‐positive neurons. The morphological differentiation of intracallosal neurons culminated in the newborns and remained pronounced in infants and children. In the adult brain, the intracallosal neurons were found only sporadically, with small somata and poorly stained dendrites. Thus, intracallosal neurons form part of a transitory neuron population with a developmental peak contemporaneous to the critical period of callosal formation. Therefore, they may be involved in processes such as axon guiding or elongation, withdrawal of exuberant axons, fasciculation, or functional tuning, which occur at that time. 相似文献
993.
Rudić JS Culafić DM Mirković DS Ješić RS Krstić MN 《World journal of gastroenterology : WJG》2010,16(48):6135-6138
AIM:To determine the effect of free serotonin concentrations in plasma on development of esophageal and gastric fundal varices. METHODS:This prospective study included 33 patients with liver cirrhosis and 24 healthy controls. Ultrasonography and measurement of serotonin concentration in plasma were carried out in both groups of subjects. The upper fiber panendoscopy was performed only in patients with liver cirrhosis. RESULTS:The mean plasma free serotonin levels were much higher in liver cirrhosis patients than in healthy controls (219.0 ± 24.2 nmol/L vs 65.4 ± 18.7 nmol/L,P < 0.0001). There was no significant correlation be-tween serotonin concentration in plasma and the size of the esophageal varices according to Spearman coefficient of correlation (rs =-0.217,P > 0.05). However,the correlation of plasma serotonin concentration and gastric fundal varices was highly significant (rs =-0.601,P < 0.01). CONCLUSION:Free serotonin is significant in pathogenesis of portal hypertension especially in development of fundal varices,indicating the clinical value of serotonergic receptor blockers in these patients. 相似文献
994.
995.
B. Filipović B. Šošić-Jurjević V. Ajdžanović D. Brkić M. Manojlović-Stojanoski V. Milošević M. Sekulić 《Osteoporosis international》2010,21(9):1609-1616
Summary
Thyroid C cells hormone, calcitonine, inhibits bone resorption. We have demonstrated that daidzein treatment of orchidectomized rats (model for osteoporosis) stimulated C cells and increased trabecular bone mass. These results suggest that, besides direct action, daidzein may also affect bone structure indirectly through enhancement of thyroid C cell activity.Introduction
Thyroid C cells produce calcitonin (CT) which acts as an inhibitor of bone resorption. In this study, the influence of daidzein treatment on thyroid C cells, bone structure, and bone function in orchidectomized (Orx) middle-aged rats was investigated.Methods
Sixteen-month-old Wistar rats were divided into Orx and sham-operated (SO) groups. Half the Orx rats were given subcutaneous injections of daidzein (30 mg/kg b.w./day) for 3 weeks. CT-immunopositive thyroid C cells were morphometrically analyzed. The metaphyseal region of the proximal tibia was measured histomorphometrically, and cancellous bone area (B.Ar), trabecular thickness (Tb.Th), trabecular number (Tb.N), and trabecular separation (Tb.Sp) were calculated. Serum samples were analyzed for CT and osteocalcin (OC), calcium (Ca) and phosphorus concentrations, and urine samples for Ca levels.Results
Treatment of Orx animals with daidzein significantly increased volume of C cells compared to the Orx rats. Daidzein also enhanced B.Ar, Tb.Th, and Tb.N and reduced Tb.Sp. The serum OC and urinary Ca concentrations decreased significantly in comparison with the Orx group.Conclusions
These findings indicate that daidzein treatment stimulates thyroid C cells, increase trabecular bone mass, and decrease bone turnover in Orx middle-aged rats, which is the model of male osteoporosis. 相似文献996.
Arnol M Knap B Oblak M Buturović-Ponikvar J Bren AF Kandus A 《Transplantation proceedings》2010,42(10):4064-4068
Cardiovascular events (CVE) are the leading cause of mortality in kidney transplant recipients. Increased left ventricular mass (LVM) is a risk factor for CVE. This study investigated the associations of LVM with impaired kidney graft function expressed as lower glomerular filtration rate (GFR) at 1 year after transplantation and future CVE beyond 1 year. The prospective study cohort included 68 nondiabetic recipients of a kidney transplant between January 2004 and December 2005 who underwent a transthoracic echocardiographic investigation at 1 year after transplantation. LVM and left ventricular hypertrophy (LVH) were assessed using 2-dimensional M-mode echocardiography. GFR was estimated (eGFR) by the 4-variable Modification of Diet in Renal Disease formula. Cox proportional hazards analysis was used to estimate cardiac CVE (angina pectoris, acute myocardial infarct, coronary angioplasty or bypass surgery, or sudden cardiac death) hazard ratios (HRs) for patients with LVH versus control subjects with no LVH at 1 year after transplantation. All patients had normal systolic function (ejection fraction >50%) with no symptoms or signs of heart failure. LVH was present in 44 patients (65%). LVM and incidence of LVH were increased in 28 patients with eGFR <60 mL/min/1.73 m2 compared with 40 patients with eGFR ≥60 mL/min/1.73 m2 (248 ± 61 g and 86% vs 210 ± 46 g and 50%, respectively; P < .01). After a median follow-up of 4.5 years, there were 18 (26.5%) cardiac CVE. The incidence of CVE was higher in patients with LVH than in patients with no LVH at 1 year after transplantation (36.4% vs 8.3%; P = .020). In adjusted analyses, LVH was associated with an increased risk for future CVE (HR, 4.69; 95% confidence interval, 1.02–21.5; P = .037). In kidney transplant recipients, a lower eGFR at 1 year after transplantation was associated with greater LVM and higher incidence of LVH. Presence of LVH was associated with an increased risk for future CVE. 相似文献
997.
Silvana Jukić Krmek Ivana Bogdan Paris Simeon Goranka Prpić Mehičić Davor Katanec Ivica Anić 《Lasers in medical science》2010,25(6):823-828
The aim of this study was to evaluate microleakage along resin restoration in cavities prepared with an erbium:yttrium–aluminium–garnet
(Er:YAG) laser, with and without acid etching, and to compare it with that in diamond-drilled cavities. Thirty intact molars
were divided into three equal groups. In the teeth in group I, class V cavities were prepared with a diamond drill. Cavities
in groups II and III were prepared with an Er:YAG laser (400 mJ/15 Hz for enamel and 250 mJ/10 Hz for dentine). The cavities
in groups I and II were acid-etched and adhesive and flowable composite were applied to all cavities. The specimens were first
immersed in dye for 24 h and then in 5% nitric acid for 72 h for softening. The fillings were extracted and photographed through
a dissecting microscope. The leakage area was measured with specially designed software. The Kruskal–Wallis test showed that
the best ranking was group II [mean range (m.r.) = 27.46], followed by group I (m.r. = 33.48) and, lastly, group III (m.r. = 45.15).
The differences between groups I and III (P = 0.023) and between groups II and III were statistically significant (P = 0.080). The least microleakage was found in those cavities prepared by Er:YAG laser and subsequently acid-etched, whereas
the most leakage was in the lased cavities that had not been etched; the traditional diamond-drilled acid-etched cavities
produced medium leakage. 相似文献
998.
999.
Zorica Cvetković Vesna Vučić Bora Cvetković Milan Petrović Danijela Ristić-Medić Jasna Tepšić Maria Glibetić 《Annals of hematology》2010,89(8):775-782
The data about the fatty acid (FA) status of non-Hodgkin lymphoma (NHL) patients are poor. Therefore, the aim of this study was to investigate the FA profile of serum phospholipids in NHL patients related to the aggressiveness and clinical stage of NHL. We analyzed the FA profile of serum phospholipids in 47 newly diagnosed, untreated NHL patients and in 29 healthy subjects. Significantly higher (p?<?0.001) levels of palmitic (16:0), oleic (18:1 n-9) and arachidonic acids (20:4 n-6), saturated and monounsaturated FA were found in NHL patients, while linoleic acid (18:2 n-6) and the levels of total polyunsaturated FA (PUFA), n-3 PUFA, eicosapentaenoic (20:5 n-3) and docosahexaenoic (DHA, 22:6 n-3) were significantly reduced (p?<?0.01). The level of oleic acid in patients with indolent NHL was significantly lower (p?<?0.05) than in more aggressive types of disease. Contents of palmitoleic acid, docosatetraenoic (22:4 n-6), and PUFA was lower in very aggressive NHL. According to clinical stage (CS), patients with CS I had significantly higher SFA and lower n-6 FA than other three groups, and group with CS IV showed significantly decreased DHA and n-3 PUFA. Our results showed an abnormal FA profile in serum phospholipids in NHL patients. 相似文献
1000.
G. Leposavić V. Pešić Z. Stojić-Vukanić K. Radojević N. Arsenović-Ranin D. Kosec M. Perišić I. Pilipović 《Experimental gerontology》2010
Alpha1-adrenoceptors (α1-ARs) are involved in neuro-thymic and thymic intercellular communications, and consequently modulation of T-cell development. Ageing is associated with a number of changes in noradrenergic neuro-effector transmission, and possibly intercellular noradrenaline (NA)-mediated communication resulting in altered responses of target cells to NA. Thus, in old animals an altered NA modulation of thymopoiesis via α1-ARs may be expected. To test this hypothesis, in old and young adult Wistar rats we examined: 1) thymic NA levels, density of noradrenergic innervation and NA synthesizing cells, as well as α1-AR expression, and 2) then the effects of 14-day-long treatment with the α1-AR blocker, urapidil, on thymocyte development. Overall, the first part of study suggested augmented NA signalling to thymic cells via α1-ARs due to increased NA availability and α1-AR thymocyte surface density in old rats. The second part of study supported this assumption. Namely, although in rats of both ages urapidil affected the same thymocyte developmental steps ultimately leading to changes in the relative number of the most mature single positive TCRαβhigh thymocytes, its effects were generally more prominent in old animals. Following urapidil treatment, the percentages of CD4 + CD8− cells, including those showing a regulatory CD4 + CD25 + RT6.1− phenotype, were increased, while CD4 − CD8+ cells decreased. In old rats, an augmented thymic escape of immature CD4 + CD8+ cells was also registered. In rats of both ages the thymic changes were accompanied by alterations in the proportions of major cell populations in the T-lymphocyte compartment of both peripheral blood and spleen, leading to an increase in the CD4+/CD8+ T-cell ratio. These alterations were also more pronounced in old rats. Moreover, in old rats following urapidil treatment the proportion of TCRαβ + cells in the periphery was slightly greater reflecting, most likely, partly enhanced thymic production of regulatory CD161 + TCRαβ + cells. Thus, the study indirectly suggests an age-associated increase in the basal α1-AR-mediated inhibitory influence of NA on thymopoiesis. 相似文献