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71.
72.
J. Keith Smith M.D. Ph.D. Gordon C. Carson III M.D. Jay D. Johnson B.S. John H. Harris Jr. M.D. D.Sc. F.A.C.R. 《Emergency radiology》1994,1(2):78-80
Purpose: To describe an educational computer aided instruction program dealing with diagnosis and classification of facial
fractures.
Methods: A program was created for use on Macintosh computers using a graphic presentation package. This program allows for
the display of high resolution digitized radiographic images and illustrations, along with integrated voice and text information.
Users can interact with the program to review complex concepts or study additional cases. Case material was obtained from
selected high quality plain radiographs and computed tomography (CT) scans obtained in the trauma center of one institution,
and was scanned on a high resolution digital scanner with image parameters optimized for viewing on the Macintosh high resolution
color monitor.
Results: The program has been installed in the computer aided instructional laboratories or trauma centers at The University
of Texas Health Science Center, Houston; The University of Alabama, Birmingham; Emory University School of Medicine, Atlanta,
Georgia; and The University of North Carolina, Chapel Hill. The program is available to radiology residents and medical students
rotating on the trauma radiology services at these institutions. Completion of the program requires 30–45 minutes.
Conclusion: Based on our initial experience, the program has been used by residents in the training programs of all institutions
with favorable results. 相似文献
73.
A. D. Craig Jr J. O. Dostrovsky 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1991,85(2):470-474
Summary The technique of antidromic mapping with a roving array of electrodes was used to demonstrate that lamina I trigeminothalamic cells responsive specifically to skin temperature project to the n. submedius (Sm) in the medial thalamus of the cat. This finding indicates that Sm receives thermoreceptive in addition to nociceptive information. 相似文献
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J. Steven Poceta MD Thomas P. Strandjord MD Richard J. Badura Jr MD Jerrold M. Milstein MD 《Pediatric neurology》1987,3(6):370-372
Two newborns, 1 male and 1 female, had both Ondine curse, also known as congenital, central hypoventilation syndrome, and Hirschsprung disease. Both infants demonstrated insufficient respiration while asleep and normal respiration when awake. The lesser affected child had an otherwise normal neurologic examination, but suffered from seizures. He died at 18 months of age; neuropathologic examination of the brain was unremarkable. The girl had a severe and ultimately fatal form of this disorder and manifested a variety of neurologic abnormalities indicative of developmental failure of the neural crest-derived tissues. These abnormalities included unreactive pupils and deafness. She died at 40 days of age; autopsy permission was denied. The etiology of sleep apnea is not known. Mechanisms of central integration may be abnormal but the association with neural crest maldevelopment implicates the peripheral nervous system. 相似文献
76.
Human Aldehyde Dehydrogenase: Kinetic Identification of the Isozyme for Which Biogenic Aldehydes and Acetaldehyde Compete 总被引:1,自引:0,他引:1
Alexander D. MacKerell Jr PhD Erich E. Blatter BS Regina Pietruszko PhD 《Alcoholism, clinical and experimental research》1986,10(3):266-270
Michaelis constants and maximal velocities for phenylacetaldehyde (a metabolite of phenylethylamine), 3,4-dihydroxyphenylacetaldehyde (a metabolite of dopamine), 5-hydroxyindole acetaldehyde (a metabolite of serotonin), and 3,4-dihydroxyphenylglycolaldehyde (a metabolite of epinephrine and norepinephrine) have been determined for both cytoplasmic (E1) and mitochondrial (E2) isozymes of human liver aldehyde dehydrogenase (EC 1.2.1.3). Kinetic constants with biogenic aldehydes have never been previously determined for individual homogeneous isozymes of aldehyde dehydrogenase from any species. Mathematical treatment of these constants suggests that competition with acetaldehyde during alcohol metabolism would severely inhibit dehydrogenation of biogenic aldehydes with the mitochondrial and not the cytoplasmic isozyme of human liver aldehyde dehydrogenase. 相似文献
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Steven R. Alexander Gerald S. Arbus Khalid M. H. Butt Susan Conley Richard N. Fine Ira Greifer Alan B. Gruskin William E. Harmon Paul T. McEnery Thomas E. Nevins Nadia Nogueira Oscar Salvatierra Jr Amir Tejani 《Pediatric nephrology (Berlin, Germany)》1990,4(5):542-553
This report of the North American Pediatric Transplant Cooperative Study summarizes data contributed by 57 participating centers on 754 children with 761 transplants from 1 January 1989 to 16 February 1989. Data collection was initiated in October 1987 and follow-up of all patients is ongoing. Transplant frequency increased with age; 24% of the patients were less than 5 years, with 7% being under 2 years. Common frequent diagnoses were: aplastic/dysplastic kidneys (18%), obstructive uropathy (16%), and focal segmental glomerulosclerosis (12%). Preemptive transplant, i.e., transplantation without prior maintenance dialysis, was performed in 21% of the patients. Dialytic modalities pretransplant were peritoneal dialysis in 42% and hemodialysis in 25%. Bilateral nephrectomy was reported in 29%. Live-donor sources accounted for 42% of the transplants. Among cadaveric donors, 41% of the donors were under 11 years old. During the first post-transplant month, maintenance therapy was used similarly for live-donor and cadaver source transplants, with prednisone, cyclosporine, and azathioprine used in 93%, 83%, and 81%, respectively. Triple therapy with prednisone, cyclosporine, and azathioprine was used in 78%, 75%, and 75% of functioning cadaver source transplants at 6 months, 12 months, and 18 months as opposed to 60%, 63%, and 54% for live-donor procedures, with single-drug therapy being uncommon. Rehospitalization during months 1–5 occurred in 62% of the patients, with treatment of rejection and infection being the main causes. Additionally, 9% were hospitalized for hypertension. During months 6–12 and 12–17, 30% and 28% of the patients with functioning grafts were rehospitalized. Times to first rejection differed significantly for cadaver and live-donor transplants. The median time to the first rejection was 36 days for cadaver transplants and 156 days for live-donor transplants. Overall, 57% of treated rejections were completely reversible although the complete reversal rate decreased to 37% for four or more rejections. One hundred and fifty-two graft failures had occurred at the time of writing, with a 1-year graft survival estimate of 0.88 for live-donor and 0.71 for cadaver source transplants. In addition to donor source, recipient age is a significant prognostic factor for graft survival. Among cadaver donors, decreasing donor age is associated with a decreasing probability of graft survival. Thirty-five deaths have occurred; 16 attributed to infection and 19 to other causes. The current 1-year survival estimate is 0.94. There have been 9 malignancies.A list of all participating centers and the names of the investigators is printed on pages 552–553 相似文献
80.
F. Horak Jr S. Matthews† G. Ihorst‡ S. H. Arshad† T. Frischer J. Kuehr‡ A. Schwieger‡ J. Forster‡ the SPACE study group 《Clinical and experimental allergy》2004,34(8):1220-1225
BACKGROUND: Sensitization to house dust mite (HDM) is an important risk factor for the development of asthma and allergic disease in childhood. Higher levels of HDM allergen are linked to increased sensitization to HDM. OBJECTIVE: To study the effect of mite-impermeable mattress encasings and an educational package on the development of allergies in a newborn cohort. METHODS: Six hundred and ninety-six newborns at high risk of developing allergies were enrolled in three European countries (Germany, Austria, UK) in a prospective, randomized, controlled birth-cohort study. Children were randomly assigned to an intervention and control group. Intervention measures included the use of mite-impermeable mattress encasings for the child's bed and a simple educational package on allergen avoidance. The control group received basic information about allergies. Children were followed up at age 6, 12, 18 and 24 months. RESULTS: 80.9% of the children were followed up to the age of 24 months. No difference in the prevalence of sensitization to HDM (control vs. intervention group: 8.4% vs. 6.1%, P=0.33) or the development of symptoms (recurrent wheezing 10.3% vs. 10.7%, nocturnal cough 12.5% vs. 12.5%) or allergic diseases (asthma 3.5% vs. 5.1%, eczema 20.0% vs. 19.6%, rhinitis 28.9% vs. 25.8%) could be found between the control and intervention group. CONCLUSION: In this study, HDM avoidance did not show a protective effect on the development of sensitization to HDM or symptomatic allergy in children at age 24 months. 相似文献