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131.
The breast cancer resistance protein (BCRP), also known as mitoxantrone resistance protein (MXR) or placenta ABC protein (ABC-P), is the second member of the ABCG subfamily of ABC transport proteins (gene symbol ABCG2). BCRP has been detected in acute myeloid leukaemia and in breast, colon and gastric cancer but there has been no reports regarding BCRP expression in acute lymphoblastic leukaemia (ALL). We report the first results of BCRP expression in childhood ALL. Sixty-seven children (47 initial stage, 20 relapses) with ALL were analysed for BCRP gene expression by TaqMan real-time polymerase chain reaction. The expression of BCRP in mononuclear cells obtained from the bone marrow (BM) and peripheral blood (PB) of healthy donors was also investigated. There was no relationship between BCRP expression and age, sex, initial blast cell count, prednisolone response or BM response on d 15 and 33. Patients with T-lineage ALL showed a lower expression of BCRP (P = 0.044). Kaplan-Meier analysis of the relapse-free interval showed no prognostic significance of BCRP expression when different levels of BCRP expression were used as cut-off points. No significant difference in expression of BCRP mRNA was measured between initial-stage and relapsed-stage ALL or between normal MNC obtained from BM and ALL patients. The results indicate a low expression of BCRP in childhood ALL. Relationships between BCRP and clinical, molecular or in vivo resistance characteristics of the patients were not observed.  相似文献   
132.
Urinary diversion is an essential component of the surgical procedure after cystectomy. Replacement with an orthotopic ileal neobladder should be the first choice if external urethral sphincter sparing surgery is possible, offering good long-term function, quality of life and patient's acceptance with few complications.The possible use of a variety of alternative intestinal segments widen the horizon of the reconstructive surgeon, allowing him or her to be prepared for unusual cases.Contraindications for orthotopic neobladder reconstruction include tumour location, reduced renal, liver, intestinal function, intellectual ability and physical handicaps.It is therefore important to custom tailor the appropriate mode of diversion for individual patients with a variety of options available, including ureterocutaneous stomas, intestinal conduits and continent catheterizable reservoirs and orthotopic neobladders. All these techniques require detailed knowledge of the possible metabolic problems encountered by using gastrointestinal segments and how they react in contact with urine. Modern surgical techniques such as nerve sparing surgery have the ability to preserve postoperative continence with voluntarily micturition as well as sexual function. In addition, preliminary experimental data hold great promise that the “off shelf” bladder substitute may become a technique of choice in the future, avoiding common problems encountered using current technqiues.  相似文献   
133.
GeroScience - Recent studies using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) with gadolinium-based contrast agents (GBCA) have demonstrated subtle blood–brain barrier...  相似文献   
134.
Metabolic Brain Disease - Cholecalciferol deficiency has been associated with stress-related psychiatric disorders, particularly depression. Therefore, the present study investigated the...  相似文献   
135.
Stroke is a rare but severe event after acute coronary syndrome. Relations between both arterial territories are still discussed but prevalence of asymptomatic carotid stenosis potentially implicated in the mechanism of stroke is under-investigated. This study aimed to determine the prevalence of asymptomatic carotid stenosis in that population and review the value of screening in a view to potential surgical correction or other preventive therapies. Systematic carotid Doppler ultrasound screening was implemented on 152 consecutive patients admitted to the intensive care unit due to acute coronary syndrome. Fifty-two percent of patients had at least one carotid artery stenosis determined using the NASCET method. Forty-three percent had at least one carotid stenosis <30%, 6% had mild (30–60%) stenosis, and 2.6% had high-grade (>60%) stenosis. Existence of carotid stenosis was associated with age, diabetes mellitus, hypertension, and with the extent of the coronary atherosclerosis (left main artery stenosis). In multivariate analysis, age and diabetes were independently associated with existence of a carotid stenosis. When ultrasound screening was restricted to patients identified by multivariate analysis, the prevalence of carotid stenosis potentially requiring surgical treatment rose to 4.6%. The frequency of asymptomatic carotid atherosclerosis was high in this population but lesions were mild. While the small number of high-grade lesions indicates that systematic screening is not to be recommended, screening of patients aged >65 years or with diabetes, or both, with a view to surgery may be envisaged, since the role of mild stenosis in the occurrence of stroke remains debatable.  相似文献   
136.

Purpose

This paper presents new quantitative data on a signal-to-noise ratio (SNR) study, distortion study, and targeting accuracy phantom study for our patient-mounted robot (called Arthrobot). Arthrobot was developed as an MRI-guided needle placement device for diagnostic and interventional procedures such as arthrography.

Methods

We present the robot design and inverse kinematics. Quantitative assessment results for SNR and distortion study are also reported. A respiratory motion study was conducted to evaluate the shoulder mounting method. A phantom study was conducted to investigate end-to-end targeting accuracy. Combined error considering targeting accuracy, respiratory motion, and structure deformation is also reported.

Results

The SNR study showed that the SNR changes only 2% when the unpowered robot was placed on top of a standard water phantom. The distortion study showed that the maximum distortion from the ground truth was 2.57%. The average error associated with respiratory motion was 1.32 mm with standard deviation of 1.38 mm. Results of gel phantom targeting studies indicate average needle placement error of 1.64 mm, with a standard deviation of 0.90 mm.

Conclusions

Noise and distortion of the MR images were not significant, and image quality in the presence of the robot was satisfactory for MRI-guided targeting. Combined average total error, adding mounting stability errors and structure deformation errors to targeting error, is estimated to be 3.4 mm with a standard deviation of 1.65 mm. In clinical practice, needle placement accuracy under 5 mm is considered sufficient for successful joint injection during shoulder arthrography. Therefore, for the intended clinical procedure, these results indicate that Arthrobot has sufficient positioning accuracy.
  相似文献   
137.

Background

Preoperative anemia and allogeneic blood transfusions (ABTs) may affect outcomes in cancer surgery. The prevalence of anemia, the use of ABTs, the risks of transfusions, lengths of stay and mortality of oncological patients undergoing radical cystectomy were investigated in three University Hospitals in Germany.

Patients and Methods

Hospital records of 220 consecutive patients undergoing radical cystectomy from 2010 to 2012 were retrospectively analyzed for independent risk factors of ABT and unfavorable outcomes (readmission, increased length of stay (LOS) or death) using multivariate regression analysis.

Results

Preoperative anemia was present in 40%. 70% of patients received blood transfusions. Low preoperative and intraoperative nadir hemoglobin levels were associated with receipt of ABT (OR 1.33, P?=?0.04 and OR 2.94, P?<?0.001 respectively). Transfusion of ten or more red blood cell units (RBCs) during the entire hospital stay was a predictor of an increased LOS (P?<?0.001) and death (OR 52, 95%CI [5.9, 461.3], P?<?0.001), compared to non-transfused patients. Preoperative ABT and ASA scores were associated with ≥10RBCs.

Conclusion

Anemic patients undergoing radical cystectomy had a high risk to receive ABTs. Preoperative transfusions and transfusion of ≥10RBCs during the entire hospital stay may increase patient`s mortality.Prospective, randomized controlled studies have to follow this study.  相似文献   
138.
Background: Use of new psychoactive substances (NPS) has increased over the last decade. During this period, variability of both clinical presentations and chemical compositions of these compounds has increased. Synthetic cannabinoids (SCs) are the most commonly used NPS and there are more than 100 documented unique molecules in this class. “Black Mamba”, often associated to ADB-FUBINACA, is the most commonly used SC in Colorado. It has been linked to kidney injury, myocardial toxicity, seizures, and death.

Objectives: We aim to identify the chemical constituents and quantification of eight cases of reported “Black Mamba” use in order to further understand the clinical variability in patients presenting for emergency stabilization.

Methods: We report data from eight cases of reported “Black Mamba” use prospectively captured through the Colorado site of the Psychoactive Surveilance Consortium and Analysis Network (P SCAN). P SCAN is a geographically representative group of academic hospitals that capture clinical presentation, outcome, and biologic samples from patients that present for emergency stabilization following NPS use. Serum and urine samples were analyzed and quantified by liquid chromatography-quadrupole time-of-flight mass spectrometry after a qualitative screen for over 600 unique NPS compounds.

Results: In the reported eight cases, the median age was 28 years old. There were four male and four females. Four patients had agitation/delirium and four patients had chest pain. Normal saline, benzodiazepines and ondansetron were the common treatment provided in the emergency department (ED). Two patients were discharged from the ED and six patients being admitted for emergency observation with a median length of stay (LOS) of six hours. No deaths were reported. Confirmatory testing revealed that only five patients (62.5%) had SCs found in blood or urine samples. Cocaine, NRG-3, 3-methoxyphencyclidine hydrochloride (MeO-PCP), and methamfetamine were identified in other presentations.

Conclusions: The wide range of clinical presentations from “Black Mamba” use may be explained by the wide variability of chemical constituents found by laboratory analysis.  相似文献   

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