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101.
Spaced training is generally more effective than massed training for learning and memory, but the molecular mechanisms underlying this trial spacing effect remain poorly characterized. One potential molecular basis for the trial spacing effect is the differential modulation, by distinct temporal patterns of neuronal activity, of protein synthesis-dependent processes that contribute to the expression of specific forms of synaptic plasticity in the mammalian brain. Long-term potentiation (LTP) is a type of synaptic modification that may be important for certain forms of memory storage in the mammalian brain. To explore the role of protein synthesis in the trial spacing effect, we assessed the protein synthesis dependence of hippocampal LTP induced by 100-Hz tetraburst stimulation delivered to mouse hippocampal slices in either a temporally massed (20-s interburst interval) or spaced (5-min interburst interval) fashion. To extend our studies to the behavioral level, we trained mice in fear conditioning using either a massed or spaced training protocol and examined the sensitivity of long-term memory to protein synthesis inhibition. Larger LTP was induced by spaced stimulation in hippocampal slices. This improvement of synaptic potentiation following temporally spaced synaptic stimulation in slices was attenuated by bath application of an inhibitor of protein synthesis. Further, the maintenance of LTP induced by spaced synaptic stimulation was more sensitive to disruption by anisomycin than the maintenance of LTP elicited following massed stimulation. Temporally spaced behavioral training improved long-term memory for contextual but not for cued fear conditioning, and this enhancement of memory for contextual fear was also protein synthesis dependent. Our data reveal that altering the temporal spacing of synaptic stimulation and behavioral training improved hippocampal LTP and enhanced contextual long-term memory. From a broad perspective, these results suggest that the recruitment of protein synthesis-dependent processes important for long-term memory and for long-lasting forms of LTP can be modulated by the temporal profiles of behavioral training and synaptic stimulation.  相似文献   
102.
Determining an individual's "ideal" body weight is fundamental in nutritional therapy. A simulation of the human body to a cylindrical volumetric model permits the calculation of the ideal body weight from the measured height, interacromioclavicular distance, and humeral length. A group of 189 healthy normal volunteers were assessed. The calculated "Pitt" ideal body weight correlated closely (r = 0.88 for males, r = 0.72 for women) with values obtained from the Metropolitan tables. The technique provides an estimate of ideal body weight based upon reproducible, easily obtained measurements of fixed bony landmarks.  相似文献   
103.
Activities of glucose 6-phosphate dehydrogenase and 6-phosphogluconate dehydrogenase of calf trabecular meshwork were measured and found to be 0.23 and 0.47 mumole/min/g tissue, respectively. Glucose 6-phosphate dehydrogenase was purified 450-fold with a yield of 91% by anion exchange chromatography and 2',5'-ADP agarose affinity chromatography. It was activated by Ca2+, Mg2+, and Mn2+. It was deactivated by p-chloromecuribenzoate, p-chloromercuribenzene sulfonate, and iodoacetamide, but this deactivation could be prevented by pretreatment with cysteine or glutathione. Its rate was regulated by the NADPH/NADP+ ratio, being maximal at a ratio of 0, and negligible at a ratio of 10. At the physiological ratio of 5, its rate was approximately half maximal. On disc gel electrophoresis of both the crude and purified enzyme, seven bands of glucose 6-phosphate dehydrogenase activity could be seen. The isozyme pattern was similar to that of calf retina, but different from that of calf liver. These data suggest that trabecular meshwork is well supplied with the capacity to generate NADPH. Typical demands for NADPH may be to detoxify H2O2 and/or organic peroxides through the glutathione peroxidase/glutathione reductase system, and both generating and removing products of the "killing reaction" during phagocytosis.  相似文献   
104.
Survival is an objective criteria, reliable, easy to measure and easy to analyse. But this criteria, the most important in almost all therapeutic trials, is a very rough one and not all fitted to many questions raised in cancer treatment decision making. We suggest a new criteria, combining quality and quantity of survival, which is equivalent in years of survival at a maximal quality level to the time of survival at a varying level of a cancer patient. This criteria could be usefull in the majority of "palliative" clinical trials (advanced cancers, recurrences, metastatic evolution...).  相似文献   
105.
Maternal and Child Health Journal - Vietnam’s post-war globalization, economic development, and urbanization have contributed to a nutrition transition from traditional diets to...  相似文献   
106.
Maternal and Child Health Journal - The article “Factor Structure and Equivalence of Maternal Resources for Care in Bangladesh, Vietnam, and Ethiopia”, written by Sulochana Basnet,...  相似文献   
107.
Health Services and Outcomes Research Methodology - An interrupted time series with a parallel control group (ITS-CG) design is a powerful quasi-experimental design commonly used to evaluate the...  相似文献   
108.
ObjectivesTo examine data from Delaware nursing homes to determine prevalence of age-related eye diseases (AREDs), vision impairment, and blindness and to compare the findings with the results of 11 US investigations of vision and eye health in nursing homes.DesignThis is a cross-sectional, retrospective study of nursing home patients.Setting and ParticipantsTwenty nursing homes in Delaware participated in the study, yielding comprehensive eye examination records for 2019 study participants.MethodsSummary statistics and regression analyses.ResultsThe overall prevalence of vision impairment or blindness was 63.8% and was above 60% for each age, sex, and race category. Prevalence of vision impairment or blindness was 68.4% among patients with cataracts, 69.4% among patients with macular degeneration, 70.5% among patients with glaucoma, and 68.4% among patients with diabetic retinopathy. Prevalence of blindness was 14.1%. Among patients with AREDs, prevalence of blindness ranged from 15.0% for patients with cataracts to 22.6% for patients with diabetic retinopathy. When compared with other investigations, we found wide variation in vision and eye factors reported and wide variation in the prevalence of those factors. Only 4 studies diagnosed both AREDs and visual function. Seven studies reported AREDs, and 7 reported vision impairment and/or blindness. Vision impairment or blindness ranged from 29% to 67%; cataract ranged from 32% to 83%; macular degeneration ranged from 4.6% to 70.7%. Glaucoma ranged from 5.3% to 41.4%; diabetic retinopathy ranged from 1.7% to 3.1%.Conclusions and ImplicationsComprehensive eye examinations showed that vision impairment and blindness affected 63.8% of nursing home residents. Compared with other studies, there was a wide range of vision factors reported and wide variation in the prevalence of vision impairment or blindness and AREDs. This investigation suggests the importance of eye care in nursing homes and the importance of reporting standard vision and eye health factors to inform policy and practice.  相似文献   
109.
Lasers in Medical Science - Long-pulsed 1064-nm (LP1064) and 755-nm (LP755) lasers have been demonstrated as effective treatments for leg veins. However, few studies of these treatments on Asian...  相似文献   
110.
BackgroundEstablishing clear risk factors for complications such as urinary tract infection (UTI) after arthroplasty procedures helps guide clinical practice and provides more information to both surgeons and patients. This study aims to assess selected preoperative patient characteristics as risk factors for postoperative UTI after primary total hip and knee arthroplasties (THA and TKA).MethodsThis was a retrospective analysis using current procedural terminology codes to investigate the American College of Surgeons National Surgical Quality Improvement Program (NSQIP) database for patients who underwent THA or TKA from 2010 to 2017. Patients were classified for UTI by NSQIP guidelines. Patient samples with all possible covariates were included for multivariate logistic regression analysis and assessed for independent associations.ResultsIn a cohort of 983 identified patients (983 of 119,096; 0.83%): ages 57+ years, preoperative red blood cell (RBC) transfusion, perioperative RBC transfusion, bleeding disorders, operative time 110+ minutes, preoperative steroid use, diabetes, pulmonary comorbidities, body mass index 30+ kg/m2 were independent risk factors for postoperative UTI after THA. In a cohort of 1503 identified patients (1503 of 189,327; 0.8%): ages 60+ years, preoperative RBC transfusion, perioperative RBC transfusion, anemia, platelets less than 150k, preoperative steroid use, diabetes, and body mass index 30+ kg/m2 were independent risk factors for postoperative UTI after TKA. Male sex was associated with a decreased risk of UTI in both THA and TKA.ConclusionThis study provides novel evidence on risk factors associated with the development of UTI after THA or TKA. Clinicians should be aware of risk factors in the manifestation of postoperative UTI after primary THA or TKA procedures.  相似文献   
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