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1.
Gerald T Voelbel Marsha E Bates Jennifer F Buckman Gahan Pandina Robert L Hendren 《Neuropsychopharmacology》2006,60(9):942-950
BACKGROUND: Impaired neuropsychological test performance, especially on tests of executive function and attention, is often seen in children diagnosed with autism spectrum disorders (ASD). Structures involved in fronto-striatal circuitry, such as the caudate nucleus, may support these cognitive abilities. However, few studies have examined caudate volumes specifically in children with ASD, or correlated caudate volumes to cognitive ability. METHODS: Neuropsychological test scores and caudate volumes of children with ASD were compared to those of children with bipolar disorder (BD) and of typically developing (TD) children. The relationship between test performance and caudate volumes was analyzed. RESULTS: The ASD group displayed larger right and left caudate volumes, and modest executive deficits, compared to TD controls. While caudate volume inversely predicted performance on the Wisconsin Card Sorting Test in all participants, it differentially predicted performance on measures of attention across the ASD, BD and TD groups. CONCLUSIONS: Larger caudate volumes were related to impaired problem solving. On a test of attention, larger left caudate volumes predicted increased impulsivity and more omission errors in the ASD group as compared to the TD group, however smaller volume predicted poorer discriminant responding as compared to the BD group. 相似文献
2.
Use of sonography to evaluate carotid atherosclerosis in the elderly. The Cardiovascular Health Study. CHS Collaborative Research Group 总被引:10,自引:0,他引:10
D H O'Leary J F Polak S K Wolfson M G Bond W Bommer S Sheth B M Psaty A R Sharrett T A Manolio 《Stroke; a journal of cerebral circulation》1991,22(9):1155-1163
Carotid sonography is being performed on more than 5,000 participants in the Cardiovascular Health Study, a prospective, multicenter study of cardiovascular disease in men and women aged 65 years and older. The sonographic methods used to examine and measure the extracranial carotid arteries are described. Initial validation studies were performed on 61 subjects with a mean age of 68.6 years. Analysis of within- and between-sonographer differences and between-reader differences were performed for selected variables. In general, the mean absolute differences for within- and between-sonographer comparisons were small, with even less variability between readers. Variability was less for the common carotid artery than for the internal carotid artery. These data suggest that carotid sonography is a reliable and reproducible method for use in the study of carotid atherosclerosis in population studies. 相似文献
3.
4.
Specific factors have limited the interpretation of studies regarding the efficacy, effectiveness and efficiency of technology in anaesthesia. Some of these problems are reviewed, including the lack of specific outcomes necessitating the use of intermediate measures (e.g., hypoxaemia, myocardial ischaemia), which are not necessarily related to ultimate patient outcomes. This emphasizes the need for anaesthesia investigators to define fundamental issues specifically and design studies accordingly. With respect to anaesthesia monitors, the “lead time” or early warning provided by a monitor relative to that required to alter therapy effectively needs to be defined better and compared with the “lead time” without the monitor. After defining the benefit of a monitor, investigators should analyze the cost relative to alternatives (cost-benefit and cost-effectiveness). A hierarchical model to guide technology assessment is presented that addresses in order, the scientific basis of the technology, and the influence on the patient followed by societal issues. Anaesthetists have relied on traditional methods of technology assessment adopted from other disciplines. These methodologies do not address specific issues related to anaesthesia practice (such as “lead time”). In defining problems specific to the specialty of anaesthesia, new outcome measures that focus on the human factors related to decision-making in the operating room need to be developed. Future evaluations of anaesthesia technology require innovative approaches that address specific anaesthesia-related problems. One such approach is the use of simulation-based studies of response patterns to critical incidents. 相似文献
5.
6.
Mechanisms of quinolone resistance in Escherichia coli: characterization of nfxB and cfxB, two mutant resistance loci decreasing norfloxacin accumulation. 总被引:29,自引:23,他引:6 下载免费PDF全文
D C Hooper J S Wolfson K S Souza E Y Ng G L McHugh M N Swartz 《Antimicrobial agents and chemotherapy》1989,33(3):283-290
7.
N Wolfson R D Galpin T C Hearn R B Willis 《Bulletin of the Hospital for Joint Diseases》1992,52(1):36-38
Growth of the regenerate is affected by various factors during the course of Ilizarov distractional osteogenesis. One of the chief biomechanical factors that influences the quality and rate of bone formation is fixator stiffness. A four-ring Ilizarov apparatus was configured around a synthetic tibia. In a series of trials involving a uniform axial load, different transfixing wire tensions, and the separation of paired proximal and distal rings, fragment displacement was measured. Preliminary results suggest that the effect produced by the distraction of ring pairs on interfragmentary micromotion is as significant as pretensioning of the wires. 相似文献
8.
Marsha Bernard Kuhar 《AAOHN journal》2002,50(8):360-364
1. The Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (ATPIII) will significantly increase the number of Americans treated for hypercholesterolemia. 2. The ATPIII focuses on lowering low density lipoprotein cholesterol as a primary initiative and using exercise, diet, and pharmacotherapy as a means for lowering coronary heart disease and risks. 3. The new guidelines list low density lipoprotein cholesterol levels of less than 100 mg/dL as optimal for all clients. 4. The ATPIII places increased attention on high triglyceride levels (> 200 mg/dL) and on early detection and appropriate aggressive treatment for clients at risk for coronary heart disease and events. 相似文献
9.
Marsha Wolfson 《Seminars in dialysis》1988,1(1):28-32
Little is actually known about the minimum daily requirement for most vitamins in the patient with end-stage renal disease. Many of the studies reviewed suffer from lack of adequate control populations and differing methodologies, making comparisons between these studies difficult. However, patients with renal failure have many restrictions on their dietary intake, frequently suffer from intercurrent illness, and would seem to be at risk for vitamin deficiency. Also, metabolic abnormalities associated with the loss of kidney function may increase the daily requirements for certain vitamins. It is unlikely that dialysis losses of the water-soluble vitamins alone could account for vitamin depletion, and these other factors are likely to play a much more important role. It is of interest to note that the studies which demonstrate little or no vitamin deficiencies are those studies which have been carried out more recently (8, 9, 17). The patients were usually given some vitamin supplementation prior to or during the period of study and thus it is not surprising that most patients failed to demonstrate vitamin deficiency. It is also likely that heightened awareness regarding the propensity for patients with renal failure to develop deficiencies of the water-soluble vitamins has resulted in better dietary instruction and earlier intervention with vitamin supplementation. More efficient dialytic methods have also reduced the restrictions on many foods, and patients are no longer instructed to boil all their fresh vegetables. Although there may be the risk of toxicity when vitamin supplementation is overzealously administered to patients with reduced renal excretory function, it seems prudent to administer some of these water-soluble vitamins to patients with end-stage renal disease who are treated with intermittent dialysis therapy (Table 1). Certainly, this is not a very costly approach. Further studies should be carried out to better evaluate vitamin nutriture in chronically uremic and maintenance dialysis patients and to more rigorously define the minimum dose that would prevent deficiency and avoid toxicity. 相似文献
10.
Julie D Rippeth Robert K Heaton Catherine L Carey Thomas D Marcotte David J Moore Raul Gonzalez Tanya Wolfson Igor Grant 《Journal of the International Neuropsychological Society》2004,10(1):1-14
Both HIV infection and methamphetamine dependence can be associated with brain dysfunction. Little is known, however, about the cognitive effects of concurrent HIV infection and methamphetamine dependence. The present study included 200 participants in 4 groups: HIV infected/methamphetamine dependent (HIV+/METH+), HIV negative/methamphetamine dependent (HIV-/METH+), HIV infected/methamphetamine nondependent (HIV+/METH-), and HIV negative/methamphetamine nondependent (HIV-/METH-). Study groups were comparable for age, education, and ethnicity, although the HIV-/METH- group had significantly more females. A comprehensive, demographically corrected neuropsychological battery was administered yielding a global performance score and scores for seven neurobehavioral domains. Rates of neuropsychological impairment were determined by cutoff scores derived from performances of a separate control group and validated with larger samples of HIV+ and HIV- participants from an independent cohort. Rates of global neuropsychological impairment were higher in the HIV+/METH+ (58%), HIV-/METH+ (40%) and HIV+/METH- (38%) groups compared to the HIV-/METH- (18%) group. Nonparametric analyses revealed a significant monotonic trend for global cognitive status across groups, with least impairment in the control group and highest prevalence of impairment in the group with concurrent HIV infection and methamphetamine dependence. The results indicate that HIV infection and methamphetamine dependence are each associated with neuropsychological deficits, and suggest that these factors in combination are associated with additive deleterious cognitive effects. This additivity may reflect common pathways to neural injury involving both cytotoxic and apoptotic mechanisms. 相似文献