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991.
Udassi JP Udassi S Shih A Lamb MA Porvasnik SL Zaritsky AL Haque IU 《Resuscitation》2012,83(6):750-754
Objective
ACD-CPR improves coronary and cerebral perfusion. We developed an adhesive glove device (AGD) and hypothesized that ACD-CPR using an AGD provides better chest decompression resulting in improved carotid blood flow as compared to standard (S)-CPR.Design
Prospective, randomized and controlled animal study.Methods
Sixteen anesthetized and ventilated piglets were randomized after 3 min of untreated VF to receive either S-CPR or AGD-ACD-CPR by a PALS certified single rescuer with compressions of 100 min−1 and C:V ratio of 30:2. AGD consisted of a modified leather glove exposing the fingers and thumb. A wide Velcro patch was sewn to the palmer aspect of the glove and the counter Velcro patch was adhered to the pig's chest wall. Carotid blood flow was measured using ultrasound. Data (mean ± SD) was analyzed using one way ANOVA and unpaired t-test; p-value ≤ 0.05 was considered statistically significant.Results
Right atrial pressure (mm Hg) during the decompression phase was lower during AGD-ACD-CPR (−3.32 ± 2.0) when compared to S-CPR (0.86 ± 1.8, p = 0.0007). Mean carotid blood flow was 53.2 ± 27.1 (% of baseline blood flow in ml/min) in AGD vs. 19.1 ± 12.5% in S-CPR, p = 0.006. Coronary perfusion pressure (CPP, mm Hg) was 29.9 ± 5.8 in AGD vs. 22.7 ± 6.9 in S-CPR, p = 0.04. There was no significant difference in time to ROSC and number of epinephrine doses.Conclusion
Active chest decompression during CPR using this simple and inexpensive adhesive glove device resulted in significantly better carotid blood flow during the first 2 min of CPR. 相似文献992.
993.
Chen CH Liao WC Liu YH Chen WC Hsia TC Hsu WH Shih CM Tu CY 《The American journal of emergency medicine》2012,30(1):45-50
Objective
The study aimed to assess the clinical efficacy of pigtail catheter drainage for patients with a first episode of secondary spontaneous pneumothorax (SSP) and different associated conditions.Methods
We retrospectively reviewed the records of patients with SSP who received pigtail catheter drainage as their initial management between July 2002 and October 2009. A total of 168 patients were included in the analysis; 144 (86%) males and 24 (14%) females with a mean age of 60.3 ± 18.3 years (range, 17-91 years). Data regarding demographic characteristics, pneumothorax size, complications, treatments, length of hospital stay, and associated conditions were analyzed.Results
In total, 118 (70%) patients were successfully treated with pigtail catheter drainage, and 50 (30%) patients required further management. Chronic obstructive lung disease was the most common underlying disease (57% of cases). Secondary spontaneous pneumothorax associated with infectious diseases had a higher rate of treatment failure than SSP associated with obstructive lung conditions (19/38 [50%] successful vs 78/104 [75%] successful, P = .004) and malignancy (19/38 [50%] successful vs 13/16 [81%] successful, P = .021). Moreover, patients with SSP associated with infectious diseases had a longer length of hospital stay than those with obstructive lung conditions (23.8 vs 14.5 days, P = .003) and malignancy (23.8 vs 12.1 days, P = .017). No complications were associated with pigtail catheter drainage.Conclusions
A higher rate of treatment failure was noted in SSP patients with infectious diseases; thus, pigtail catheter drainage is appropriate as an initial management for patients with SSPs associated with obstructive lung conditions and malignancy. 相似文献994.
Gerard DeMers William J. Meurer Richard Shih Steve Rosenbaum Gary M. Vilke 《The Journal of emergency medicine》2012
Background
Alteplase (tPA) is a United States (US) Food and Drug Administration-approved treatment for acute ischemic stroke, though there are significant barriers to thrombolytic use, including Emergency Physicians' (EPs') concern for level of supporting evidence.Study Objectives
To review the medical literature on the topic of acute cerebrovascular accident (CVA) management and to offer EPs evidence-based recommendations for patients who present to the Emergency Department with an acute CVA.Methods
A MEDLINE literature search from 1990 to 2011 and limited to human studies written in English for articles with keywords of: CVA AND (thromboly* OR alteplase). Guideline statements and non-systematic reviews were excluded. Studies targeting differences between specific populations (males vs. females) were excluded. Studies identified then underwent a structured review from which results could be evaluated.Results
There were 407 papers on thrombolytic use screened, and 15 appropriate articles were rigorously reviewed and recommendations given. Conclusions: tPA is an effective treatment for stroke when given in prepared stroke centers; EPs and hospitals treating stroke patients with tPA need to have the necessary resources in place and a specific plan for timely care of patients with acute stroke. 相似文献995.
Radiation is a potent inducer of DNA damage leading to both random DNA loss and mutation. As part of a study focused on the mechanism whereby cells undergo loss of heterozygosity (LOH), a region of common LOH telomeric termination at 11q24 was observed in clones of H292 mucoepidermoid cells established after irradiation (IR). A 10-kbp region including the telomeric extent of LOH termination was analyzed after IR using six sets of ligation-mediated polymerase chain reaction (PCR) primers to detect the presence of DNA breaks. A cluster of DNA breaks was detected that closely mapped to the telomeric extent of LOH and which were observed up to 8 hr after IR. Repeating the experiment in the presence of the inhibitor of apoptosis, zVAD.fmk, did not change the location or amount of cleavage. A similar distribution of breaks was also seen in the MCF-10A breast cancer cell line after IR. Further inspection of the involved region showed that 22/32 and 7/7 DNA breaks found in H292 and MCF-10A cells, respectively, were located either in or immediately adjacent to an AluSx1 sequence, itself ≈ 1 kbp 5' to an AluSq2 that was in an inverted orientation to the AluSx1. The region between the inverted Alu repeats was notable for both DNAse hypersensitivity and an open chromatin conformation inferred from histone modification data. These factors may contribute to genomic instability at this location. 相似文献
996.
Mathews MS Blickenstaff JW Shih EC Zamora G Vo V Sun CH Hirschberg H Madsen SJ 《Journal of biomedical optics》2012,17(5):058001
We study the use of photochemical internalization (PCI) for enhancing chemotherapeutic response to malignant glioma cells in vitro. Two models are studied: monolayers consisting of F98 rat glioma cells and human glioma spheroids established from biopsy-derived glioma cells. In both cases, the cytotoxicity of aluminum phthalocyanine disulfonate (AlPcS2a)-based PCI of bleomycin was compared to AlPcS(2a)-photodynamic therapy (PDT) and chemotherapy alone. Monolayers and spheroids were incubated with AlPcS(2a) (PDT effect), bleomycin (chemotherapy effect), or AlPcS(2a)+bleomycin (PCI effect) and were illuminated (670 nm). Toxicity was evaluated using colony formation assays or spheroid growth kinetics. F98 cells in monolayer/spheroids were not particularly sensitive to the effects of low radiant exposure (1.5 J/cm(2) @ 5 mW/cm(2)) AlPcS(2a)-PDT. Bleomycin was moderately toxic to F98 cells in monolayer at relatively low concentrations-incubation of F98 cells in 0.1 μg/ml for 4 h resulted in 80% survival, but less toxic in human glioma spheroids respectively. In both in vitro systems investigated, a significant PCI effect is seen. PCI using 1.5 J/cm(2) together with 0.25 μg/ml bleomycin resulted in approximately 20% and 18% survival of F98 rat glioma cells and human glioma spheroids, respectively. These results show that AlPcS(2a)-mediated PCI can be used to enhance the efficacy of chemotherapeutic agents such as bleomycin in malignant gliomas. 相似文献
997.
998.
Chueh-Lung Hwang Chong-Jen Yu Jin-Yuan Shih Pan-Chyr Yang Ying-Tai Wu 《Supportive care in cancer》2012,20(12):3169-3177
Purpose
Peak oxygen consumption (VO2peak) is an important predictive factor for long-term prognosis in patients with non-small cell lung cancer (NSCLC). The purpose of this study was to investigate whether 8 weeks of exercise training improves exercise capacity, as assessed by VO2peak, and other related factors in patients with NSCLC receiving targeted therapy.Methods
A total of 24 participants with adenocarcinoma were randomly assigned to either the control group (n?=?11) or the exercise group (n?=?13). Subjects in the exercise group participated in individualized, high-intensity aerobic interval training of exercise. The outcome measures assessed at baseline and after 8?weeks were as follows: VO2peak and the percentage of predicted VO2peak (%predVO2peak), muscle strength and endurance of the right quadriceps, muscle oxygenation during exercise, insulin resistance as calculated by the homeostasis model, high-sensitivity C-reactive protein, and quality of life (QoL) questionnaire inventory.Results
No exercise-related adverse events were reported. After exercise training, VO2peak and %predVO2peak increased by 1.6?mL?kg?1?min?1 and 5.3% (p?<?0.005), respectively; these changes were associated with improvements in circulatory, respiratory, and muscular functions at peak exercise (all p?=?0.001). The exercise group also had less dyspnea (p?=?0.01) and favorably lower fatigue (p?=?0.05) than baseline.Conclusions
Patients with NSCLC receiving targeted therapy have quite a low exercise capacity, even with a relatively high QoL. Exercise training appears to improve exercise capacity and alleviate some cancer-related symptoms. 相似文献999.
1000.
Drew PJ Shih AY Kleinfeld D 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(20):8473-8478
Neural activity in the brain is followed by localized changes in blood flow and volume. We address the relative change in volume for arteriole vs. venous blood within primary vibrissa cortex of awake, head-fixed mice. Two-photon laser-scanning microscopy was used to measure spontaneous and sensory evoked changes in flow and volume at the level of single vessels. We find that arterioles exhibit slow (<1 Hz) spontaneous increases in their diameter, as well as pronounced dilation in response to both punctate and prolonged stimulation of the contralateral vibrissae. In contrast, venules dilate only in response to prolonged stimulation. We conclude that stimulation that occurs on the time scale of natural stimuli leads to a net increase in the reservoir of arteriole blood. Thus, a "bagpipe" model that highlights arteriole dilation should augment the current "balloon" model of venous distension in the interpretation of fMRI images. 相似文献