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101.
Purpose: The aim of this study was to evaluate phospholipid metabolism in patients with malformations of cortical development (MCDs). Methods: Thirty‐seven patients with MCDs and 31 control subjects were studied using three‐dimensional phosphorus magnetic resonance spectroscopy (31P‐MRS) at 3.0 T. The voxels in the lesions and in the frontoparietal cortex of the control subjects were compared (the effective volumes were 12.5 cm3). Robust quantification methods were applied to fit the time‐domain data to the following resonances: phosphoethanolamine (PE); phosphocholine (PC); inorganic phosphate (Pi); glycerophosphoethanolamine (GPE); glycerophosphocholine (GPC); phosphocreatine (PCr); and α‐, β‐, and γ‐adenosine triphosphate (ATP). We also estimated the total ATP (ATPt = α‐+β‐+γ‐ATP), phosphodiesters (PDE = GPC+GPE), phosphomonoesters (PME = PE+PC), and the PME/PDE, PCr/ATPt and PCr/Pi ratios. The magnesium (Mg2+) levels and pH values were calculated based on PCr, Pi, and β‐ATP chemical shifts. Key Findings: Compared to controls and assuming that a p‐value < 0.05 indicates statistical significance, the patients with MCDs exhibited significantly lower pH values and higher Mg2+ levels. In addition, the patients with MCDs had lower GPC and PDE and an increased PME/PDE ratio. Significance: Mg2+ and pH are important in the regulation of bioenergetics and are involved in many electrical activity pathways in the brain. Our data support the idea that neurometabolic impairments occur during seizure onset and propagation. The GPC, PDE, and PME/PDE abnormalities also demonstrate that there are membrane turnover disturbances in patients with MCDs.  相似文献   
102.
Bauer M, Glenn T, Alda M, Andreassen OA, Ardau R, Bellivier F, Berk M, Bjella TD, Bossini L, Del Zompo M, Dodd S, Fagiolini A, Frye MA, Gonzalez‐Pinto A, Henry C, Kapczinski F, Kliwicki S, König B, Kunz M, Lafer B, Lopez‐Jaramillo C, Manchia M, Marsh W, Martinez‐Cengotitabengoa M, Melle I, Morken G, Munoz R, Nery FG, O’Donovan C, Pfennig A, Quiroz D, Rasgon N, Reif A, Rybakowski J, Sagduyu K, Simhandl C, Torrent C, Vieta E, Zetin M, Whybrow PC. Impact of sunlight on the age of onset of bipolar disorder. Bipolar Disord 2012: 14: 654–663. © 2012 The Authors. Journal compilation © 2012 John Wiley & Sons A/S. Objective: Although bipolar disorder has high heritability, the onset occurs during several decades of life, suggesting that social and environmental factors may have considerable influence on disease onset. This study examined the association between the age of onset and sunlight at the location of onset. Method: Data were obtained from 2414 patients with a diagnosis of bipolar I disorder, according to DSM‐IV criteria. Data were collected at 24 sites in 13 countries spanning latitudes 6.3 to 63.4 degrees from the equator, including data from both hemispheres. The age of onset and location of onset were obtained retrospectively, from patient records and/or direct interviews. Solar insolation data, or the amount of electromagnetic energy striking the surface of the earth, were obtained from the NASA Surface Meteorology and Solar Energy (SSE) database for each location of onset. Results: The larger the maximum monthly increase in solar insolation at the location of onset, the younger the age of onset (coefficient= ?4.724, 95% CI: ?8.124 to ?1.323, p = 0.006), controlling for each country’s median age. The maximum monthly increase in solar insolation occurred in springtime. No relationships were found between the age of onset and latitude, yearly total solar insolation, and the maximum monthly decrease in solar insolation. The largest maximum monthly increases in solar insolation occurred in diverse environments, including Norway, arid areas in California, and Chile. Conclusion: The large maximum monthly increase in sunlight in springtime may have an important influence on the onset of bipolar disorder.  相似文献   
103.
ObjectiveAnalyze technical details and results of laparoscopic treatment of ureterolithiasis.Materials and methodsBetween January 2005 and August 2008 it was performed laparoscopic ureterolithotomy in 22 patients in our service. Two (9%) by retroperitoneal access and 20 (91%) by transperitoneal access. Mean size of the calculi was 15 mm. with a variation from 8 mm to 23 mm. The calculus were in the upper tract in 18 patients (81,8%) and in mid ureter in 4 patients (18,2), any of the calculus were in lower ureter. Most of calculi were obstructive stones for more than 2 months. Eight patients were submited a previous section of extracorporeal shockwave lithotripsy and 2 by extracorporeal shockwave lithotripsy plus ureterolithotripsy as a calculi treatment attempt. Twelve patients had a laparoscopic ureterolithotomy as a primary indication for treatment.ResultsLaparoscopic ureterolithotomy was successful for 20 patients (90,9%), and the fails occurred in the beginning of our experiment. Mean operative time was 145 minutes with range from 70 to 240 minutes. The indwelling ureteral stent was used in 03 cases; 02 preoperative, and 01 postoperative. The ureteral suture was performed with absorbable 4.0 separated stitches in all patients. The global average of permanence in hospital was 3,3 days and the drain permanence was 7,2 days. The global complication rate was 13,6%. The global rate of stone free was 91%, and there were residual stone in 2 patients.ConclusionsThe laparoscopic treatment of ureterolithiasis besides minimally invasive, it is viable, secure and very effective. It should have taken into consideration as a procedure to extracorporeal shockwave lithotripsy and ureteroscopy. But, in cases where there are obstructive stones for a long time, in selected patients and, in special, in patients with just one kidney, it can be considered as a first line treatment. About the access, if retroperitoneal or transperitoneal; it is not still possible to affirm which would be the best one, the option must take into account the surgeon preference and experience.  相似文献   
104.
We investigated how pesticide contamination of water affects the metabolism of the silver catfish, Rhamdia quelen, by studying fish maintained at two sites with low and high anthropic activity (Lino Creek, southern Brazil). Several pesticides were found at both stream sites. After 30 days plasma glucose levels were higher in fish exposed to water in the low anthropic activity site than those exposed to water in the high anthropic activity site. Plasma K+ levels, however, were lower after exposure to low anthropic water than after exposure to high anthropic water. Moreover, values of hepatic glycogen, muscle lactate and protein were higher, but glycogen and protein of the kidney were lower in fish exposed to water at the high anthropic activity site. Our results show that these fish can be used as pesticide toxicity indicators in streams near agricultural fields.  相似文献   
105.
OBJECTIVE: Positron emission tomography (PET) was used to compare cerebral metabolic patterns in schizophrenic subjects with predominantly negative symptoms (alogia, affective flattening, avolition, and attentional impairment) and in those with predominantly positive symptoms. METHOD: Fourteen right-handed male subjects with DSM-IV schizophrenia were assigned to groups with predominantly negative or predominantly positive symptoms on the basis of their post-drug-washout scores on the Positive and Negative Syndrome Scale. The patients were compared to seven age- and gender-matched normal volunteers. PET scans with [(18)F]fluorodeoxyglucose were obtained during a degraded Continuous Performance Task to measure absolute glucose metabolic rates. Statistical parametric mapping was used to estimate the regional metabolic differences between groups. RESULTS: The subjects with predominantly negative symptoms had significant differences in glucose metabolic rates, compared to both the subjects with predominantly positive symptoms and the normal subjects. Negative symptom subjects had a lower glucose metabolic rate in the right hemisphere, especially in the temporal and ventral prefrontal cortices, compared to the other groups, and higher metabolic rates in the cerebellar cortex and in the lower deep cerebellar nuclei. Negative symptom subscale scores were negatively correlated with glucose metabolic rates for most of the brain areas that differentiated subjects with predominantly negative symptoms from those with predominantly positive symptoms. CONCLUSIONS: Schizophrenic subjects with predominantly negative symptoms have greater metabolic abnormalities than subjects with predominantly positive symptoms, particularly in frontal, temporal, and cerebellar circuitry. These results are consistent with abnormalities in corticocortical, corticobasal ganglia, mesocortical dopamine, and cerebellar-thalamic-prefrontal circuits, which may underlie the negative symptoms of schizophrenia.  相似文献   
106.
Brain metabolic effects of Neotrofin in patients with Alzheimer's disease   总被引:6,自引:0,他引:6  
Lead (Pb) is a common neurotoxicant of major public health concern. Previous studies revealed that cultured oligodendrocyte progenitor cells (OPCs) are highly vulnerable to Pb toxicity. The present study examines the effect of Pb on the survival, proliferation and differentiation of OPCs in vitro. Dose-response studies showed that> or = l5-10 microM Pb is cytotoxic to OPCs within 24 h. However, 1 microM of Pb was found to inhibit the proliferation and differentiation of OPCs without affecting cell viability. Pb markedly decreased the proliferative capability of OPCs and inhibited cell-intrinsic lineage progression of OPCs at a late progenitor stage. The Pb-induced decrease of proliferation and differentiation was abolished by inhibition of protein kinase C (PKC) with bisindolylmaleimide I, while the effect of the PKC-activating agent phorbol-12,13-didecanoate was potentiated by Pb. Furthermore, Pb exposure of OPCs caused the translocation of PKC from the cytoplasm to membrane without an increase in total cellular PKC enzymic activity. These results indicate that Pb inhibits the proliferation and differentiation of oligodendrocyte lineage cells in vitro through a mechanism requiring PKC activation.  相似文献   
107.
Idiopathic dilated cardiomyopathy (IDC) is a distinct disease of the myocardium, of unknown etiology. The disease can occur acutely, or evolve in a subacute fashion. IDC is often associated with a substantial impairment of ventricular function, which may recover over time. Although spontaneous recovery of LV function occurs in 20%-45% of newly diagnosed patients, the majority of patients do not do well. IDC has an average 5-year mortality of 20%. Abnormalities of energetics, perfusion, and adrenergic control of the myocardium are markers of the status of LV dysfunction. As the heart fails, changes occur in the production and catabolism of high-energy substrates, the efficiency of mitochondrial oxidative processes, the distribution of resting perfusion and coronary vasodilating capacity and the adrenergic receptor density and function. This article reviews the information provided by metabolic and receptor imaging in patients with IDC, and the role the data may play in patient management.  相似文献   
108.
This study was conducted to examine the oral condition and the salivary and microbiological parameters associated with dental caries in 62 children with cerebral palsy, who came from households of low socioeconomic status (Study Group). This group had mixed (6 to 11 years old) and permanent (11 to 16 years old) dentition. Dental examinations were performed to measure dental caries, plaque index, salivary levels of mutans streptococci and lactobacilli, salivary flow rate, pH of stimulated saliva, and buffer capacity of saliva. A group of 67 non-handicapped children from similar socioeconomic backgrounds also were examined using these parameters (Control Group). Data were analyzed statistically by non-parametric tests and by correlation. The results showed that children with cerebral palsy who had permanent dentitions had a higher mean decayed, missing and filled surfaces index, as well as a higher plaque index for both sexes. Microbiological examination revealed higher levels of mutans streptococci among Study Group subjects with mixed dentition than in the Control Group. Also, lactobacillus counts were higher in the Study Group, regardless of sex or dentition. With respect to salivary flow rate, pH and buffering capacity, lower mean values were obtained for the Study Group.  相似文献   
109.
Increased (intra)renal activity of the renin-angiotensin system may cause a persistent increase in renovascular resistance and intraglomerular pressure in patients with diabetes, thus contributing to the development of diabetic renal damage. The effect of chronic angiotensin II subtype 1 receptor blockade on (intra)renal hemodynamics in patients with type 2 diabetes was examined in a double-blind parallel group study. Patients were treated with 40 mg of olmesartan (n = 19) or placebo (n = 16), and renal hemodynamics were assessed before and after 12 wk of treatment using inulin and para-aminohippurate clearance techniques. Olmesartan significantly reduced 24-h ambulatory systolic and diastolic BP (both P < 0.05). In parallel, effective renal plasma flow increased significantly from 602 +/- 76 to 628 +/- 87 ml/min per 1.73 m(2), whereas filtration fraction and renovascular resistance decreased significantly (all P < 0.05). With placebo treatment, effective renal plasma flow decreased and filtration fraction increased significantly (both P < 0.05). GFR was not affected by both treatments. Active plasma renin concentration increased considerably (P < 0.05) with olmesartan therapy but remained unchanged with placebo treatment. Nitric oxide metabolism (plasma nitrate and nitrite) and asymmetric dimethylarginine blood levels were not affected by olmesartan and placebo therapy. In contrast, plasma 8-isoprostane 15(S)-8-iso-prostaglandin F(2a) concentration, a biochemical marker of oxidative stress, decreased significantly (P < 0.05) with olmesartan treatment. Chronic angiotensin II subtype 1 receptor blockade decreases (intra)renal vascular resistance and increases renal perfusion despite significant BP reduction. In addition, it significantly reduces oxidative stress. These effects of angiotensin II receptor antagonists may contribute to their beneficial long-term renal effects in patients with type 2 diabetes.  相似文献   
110.
Electrophysiological and metabolic activities in brain tissue preparations maintained in vitro may be influenced by the persistent effect of anesthetic drugs utilized during tissue dissection. In order to clarify this issue, we studied elimination kinetics of the barbiturate thiopental from the brain parenchyma in the isolated guinea pig brain maintained in vitro, arterially perfused with a protein-free saline solution [M. de Curtis, G. Biella, C. Buccellati, G. Folco, Simultaneous investigation of the neuronal and vascular compartments in the guinea pig brain isolated in vitro, Brain Res. Protoc. 3 (1998) 21-28]. At the onset of anesthesia induced by a single i.p. injection of 125 mg/kg thiopental, the brain concentration of the drug, measured by high-performance liquid chromatographic assay, was 44.22+/-5.1 mg/L (mean+/-S.E.; n=7). After 30 min of arterial perfusion in vitro with a thiopental-free solution, the cerebral levels of the barbiturate decreased to 2.03+/-0.56 mg/L (n=3), and reached values close to zero within 1 h. No significant changes in thiopental elimination curve were observed when in vitro perfusion rate was either increased or decreased. The study demonstrates that thiopental is rapidly eliminated from the brain tissue with a mono-exponential kinetic. It can be concluded that barbiturate anesthesia utilized during brain dissection is not likely to influence activities recorded from the in vitro isolated brain preparation.  相似文献   
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