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61.
According to different studies, between 5% and 10% of people suffer a single isolated seizure episode at some time in their life. However, little is known about the effects of a single seizure episode on cognitive function, and clinical investigations of this issue are not easy to perform. In this situation, animal models may be a reasonable choice. The aim of our study was to follow the time course of delayed effects of generalized clonic-tonic convulsions on learning and memory functions in rats. A clonic-tonic seizure episode was induced by a single i.p. injection of pentylenetetrazole (70 mg/kg). Different behavioral tests were performed between days 10 and 100 after the convulsant administration. A single seizure episode resulted in a gradual decline in short-term memory function as assessed by novel object recognition and social recognition tests. The seizure episode induced a quick increase in hippocampal cell proliferation; however, the excessive newly generated cells seemed to be eliminated by the time of obvious cognitive impairment. These observations are indicative of a slowly developing and long-lasting influence of a single seizure episode on cognitive function. A rather long time period between the seizure episode and the manifestations of cognitive decline provides a window for a possible therapeutic intervention, and an elaboration of such “post-conditioning” treatments may be a promising opportunity to prevent subsequent mental impairments in patients.  相似文献   
62.

Introduction

Breaking bad news may be affected not only by insufficient knowledge of a physician, but also by his attitude, religious beliefs, fears, lack of experience, etc. This survey was aimed to test the relation between physicians’ fear of own death and philosophy of life and their inclination to break bad news.

Material and methods

One hundred seventy students of the last year of medical faculty filled in a 4-item questionnaire created by the authors. The participants were asked on their opinion on whether to inform patients on upcoming death, as well as fear of their own death and willingness to receive bad news. The last question was aimed to distinguish the respondents based on their determination in philosophy of life.

Results

Ninety-three percent of respondents think that patients should be informed about unfavorable prognosis but only 86% would like to be informed about their own upcoming death. There is a negative correlation between determination of philosophy of life and fear of own death (p = 0.024), but no correlation between fear of own death and the degree of religiousness (Fisher’s accurate p = 0.18). Persons determined to receive information on their own upcoming death are more prone to inform patients about their upcoming death (ρ = 0.31; p < 0.0001).

Conclusions

Personal fear of own death and low level of determination of philosophy of life may restrain medical professionals from breaking bad news to patients. Not only knowledge of the principles, but also personal attitude should be addressed in the curriculum of physician-patient communication education.  相似文献   
63.

Introduction

The aim of this study was to evaluate changes in expression of soluble biomarkers tumor factor growth-β1 (TGF-β1), CCL5/RANTES, and sFas/Apo-1 in the urine of patients undergoing ureteropyeloplasty for ureteropelvic junction (UPJ) obstruction. These factors are connected with different processes ongoing in the obstructive uropathy. If their urine concentrations correlate with AP diameter of the renal pelvis and differential function of the affected kidney, they can be helpful in making a decision on corrective surgery.

Material and methods

Creatinine, TGF-β1, CCL5/RANTES, and sFas/Apo-1 levels were measured in the urine from the bladder and renal pelvis of 45 patients undergoing ureteropyeloplasty and from bladders of 25 patients undergoing inguinal herniorrhaphy.

Results

Levels of examined biomarkers were higher in the renal pelvis and bladder of children with UPJ obstruction as compared to controls: TGF-β1 in older children and adolescents (p < 0.05), CCL5/RANTES in the youngest and older children (p < 0.05), and sFas/Apo-1 in all patients (p < 0.05). Twelve months after surgery their levels in the bladder decreased: TGF-β1 in younger and older children (p < 0.05), CCL5/RANTES in the youngest patients and adolescents (p < 0.05), and sFas/Apo-1 in the youngest and older children (p < 0.05). A significant decrease in the AP diameter of the renal pelvis post-operatively (32.09 mm vs. 18.72 mm) (p < 0.01) and significant improvement in renal function (36.94% vs. 42.76%) (p < 0.05) were observed in the examined group.

Conclusions

Mean TGF-β1, CCL5/RANTES, and sFas/Apo-1 urine levels are significantly increased in patients with UPJ and decreased 1 year after ureteropyeloplasty. Bladder concentrations of examined factors may be clinically useful markers of obstruction.  相似文献   
64.
AIM:Тo examine the effects of nitroglycerine on portal vein haemodynamics and oxidative stress in patients with portal hypertension.METHODS:Thirty healthy controls and 39 patients with clinically verified portal hypertension and increasedvascular resistance participated in the study.Liver di-ameters,portal diameters and portal flow velocities were recorded using color flow imaging/pulsed Doppler detection.Cross-section area,portal flow and index of vascular resistance were calculated.In collected blood samples,superoxide anion radical (O 2-),hydrogen per-oxide (H 2 O 2),index of lipid peroxidation (measured as TBARS) and nitric oxide (NO) as a marker of endothelial response (measured as nitrite-NO 2-) were determined.Time-dependent analysis was performed at basal state and in 10th and 15th min after nitroglycerine (sublingual 0.5 mg) administration.RESULTS:Oxidative stress parameters changed sig-nificantly during the study.H 2 O 2 decreased at the end of study,probably via O 2-mediated disassembling in Haber Weiss and Fenton reaction;O 2-increased signifi-cantly probably due to increased diameter and tension and decreased shear rate level.Consequently O 2-and H 2 O 2 degradation products,like hydroxyl radical,initi-ated lipid peroxidation.Increased blood flow was to some extent lower in patients than in controls due to double paradoxes,flow velocity decreased,shear rate decreased significantly indicating non Newtonian char-acteristics of portal blood flow.CONCLUSION:This pilot study could be a starting point for further investigation and possible implemen-tation of some antioxidants in the treatment of portal hypertension.  相似文献   
65.
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67.

Aim

The aim of this study was to examine attention and recognition memory for faces and patterns in Rett syndrome, a severely disabling neurodevelopmental disorder caused by mutations in the X‐linked MECP2 gene.

Method

Because Rett syndrome impairs speech and hand use, precluding most neuropsychological testing, the visual paired‐comparison paradigm (VPC) was used, together with eye tracking. In the VPC, two identical stimuli are presented for familiarization. On test, the familiar stimulus and a new one are paired, and recognition inferred from preferential looking to the novel target. Attention is measured by looking time, gaze dispersion, and number/length of fixations. Twenty‐seven female patients with Rett syndrome (mean age 10y 6mo; SD 6y 8mo, age range 2–22y) from the Rett clinic at a children's hospital were assessed in this study, along with 30 age‐ and sex‐matched typically developing participants (outpatients from the same hospital).

Results

Although patients with Rett syndrome showed recognition of both faces and patterns, with novelty scores greater than chance (50%), their performance was significantly poorer than that of the typically developing comparison group. Their attention to both was less mature and marked by a more narrowly focused gaze, with fewer and longer fixations. When inspecting faces, attention to the eyes was similar in both groups; however, patients with Rett syndrome tended to ignore the nose and mouth.

Interpretation

This is one of the first studies to characterize attention and memory in individuals with Rett syndrome. Visually based techniques, such as the VPC, open a new avenue for quantifying the cognitive phenotype associated with this syndrome.  相似文献   
68.
The symptoms of Parkinson’s disease (PD) worsen over time affecting performance and causing disability. The purpose of this study was to translate the Self-Assessment Disability Scale in patients with Parkinson's disease (SADS-PD) into the Serbian language and assess its validity and reliability. From January to July 2012, 114 consecutive PD patients were recruited at the Neurology Clinic in Belgrade. The inclusion criteria were: ability to walk independently for at least 10 m, ability to stand for at least 90 s. The exclusion criteria were: cognitive impairment, the presence of other major neurologic, psychiatric, visual, audio-vestibular, and orthopedic disturbances. The 25-item SADS-PD was translated according to internationally-accepted methodology. The internal consistency of the scale was evaluated using Cronbach’s alpha coefficient. Test–retest reliability was evaluated using Kendall’s concordance coefficient for total scores. To evaluate construct validity, an exploratory factor analysis (principal component analysis, varimax rotation) was performed. Cronbach’s alpha coefficient was 0.984. Kendall’s concordance coefficient was 0.994. Duration of the disease, Hoehn & Yahr (H&Y) stage, Unified Parkinson’s Disease Rating Scale (UPDRS) motor score, history of falls, Hamilton’s Depression and Anxiety Rating Scales (HDRS and HARS) scores were significantly correlated with the total SADS-PD score. On factor analysis 25 items in the SADS-PD questionnaire were separated in two clusters with total matrix variance of 79.7 %. The psychometric properties of the cross-culturally adapted SADS-PD questionnaire (Serbian version) have outstanding validity and reliability as an instrument for evaluation of the extent of disability in patients with PD.  相似文献   
69.
70.
Arteriopathy is the leading cause of childhood arterial ischemic stroke, but its mechanisms are poorly understood. This review explores the possible role of inflammatory mechanisms and evidence for inflammatory pathophysiology in specific pediatric cerebral arteriopathies. Pathologically proven small-vessel central nervous system vasculitis provides a definitive inflammatory model where available treatments are likely improving outcomes. In contrast, a common large-vessel arteriopathy presents many features suggestive of inflammation, but definitive proof remains elusive. Recent advances and future research directions, including biomarker, neuroimaging, and pathologic approaches and how they might address these important clinical questions, are discussed.  相似文献   
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