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991.
BACKGROUND: Although computer-assisted education has been used to augment education in many areas, there are few studies of programs designed to replace lectures in a medical curriculum. OBJECTIVE: To test whether a thoughtfully designed computer program can replace a standard lecture in a pediatrics curriculum while teaching the subject matter equally well. METHODS: A computer program was developed to teach the Draw-a-Person developmental test using the multimedia-authoring tool Director. One of us (A.E.C.) tested and modified the program several times during its creation after submitting it to several objective evaluators. Thirty-nine students taking the clinical pediatrics rotation were chosen by month to interact with the program or attend the lecture. All students then scored 3 drawings and assigned them a developmental age according to the Draw-a-Person test rules. Students assigned to the computer program also completed a questionnaire evaluating the program in several subjective areas. A t test for 2 samples assuming equal variance was used to analyze the test results. RESULTS: Students receiving the lecture (control group) scored the 3 drawings as 5.43 years (age range, 4.5-8 years), 9.08 years (age range, 7-12 years), and 3.5 years (age range, 2-5 years), respectively. Those using the computer program (study group) scored the 3 drawings as 5.91 years (age range, 5-7 years), 7.68 years (age range, 7-8 years), and 4.34 years (age range, 3-5 years), respectively. The correct answers for the ages were 6, 7.75, and 4.25 years, respectively. A t test for 2 samples assuming equal variance showed that students using the computer program performed better on all 3 drawings (P<.05, P<.02, and P<.002, respectively). CONCLUSIONS: Students using the computer program were more accurate than students attending the lecture when scoring drawings and estimating a developmental age from them. These results support the conclusion that a thoughtfully designed computer program can replace a standard lecture in a pediatrics curriculum.  相似文献   
992.
993.
OBJECTIVES/HYPOTHESIS: Allergic fungal sinusitis and the role of fungi in the pathogenesis of chronic rhinosinusitis are topics of interest and controversy in rhinology. The classification of chronic rhinosinusitis as either a bacterial infection or an allergic (eosinophilic) reaction to fungi has significant implications for treatment of this disease process. We designed a study to determine whether standard isolation techniques, as employed in a university hospital mycology laboratory, could isolate and identify fungi in the intraoperative specimens from patients undergoing functional endoscopic sinus surgery for chronic rhinosinusitis. STUDY DESIGN: Forty-five random patients with a diagnosis of chronic rhinosinusitis by clinical and computed tomography criteria underwent endoscopic sinus surgery during 2001, performed by two senior surgeons (J.B.J., R.A.L.). Specimens of mucin, sinus secretions, and/or tissue were obtained intraoperatively and sent to the New York University Medical Center (New York, NY) mycology laboratory for isolation and identification of fungi. METHODS: Specimens were treated with Sputolysin and chloramphenicol; plated on Sabouraud, ChromAgar/Candida, Mycosel, and Niger seed agar plates; and incubated at 30 degrees C (or 37 degrees C) for up to 1 month. RESULTS: We were able to demonstrate the presence of fungi in 56% of intraoperative specimens obtained from patients undergoing surgery for chronic rhinosinusitis. CONCLUSIONS: Using a standard hospital mycology laboratory protocol, which is relatively inexpensive and readily available, fungus can be isolated from a majority of patients undergoing functional endoscopic sinus surgery for chronic rhinosinusitis. Educational statement: Discuss the possible role of fungus in chronic rhinosinusitis and evaluate the efficacy of documenting the presence of fungus in a routine fashion to encourage clinically relevant directed treatments.)  相似文献   
994.
BACKGROUND: Acute bacterial rhinosinusitis (ABRS) is a common illness that is routinely managed by physicians from several different specialties. However, the actual diagnostic and treatment preferences of physicians from these different specialties are not known. OBJECTIVE: To determine whether the radiographic evaluation and management of community-acquired ABRS differs according to medical specialty. DESIGN, SETTING, AND PARTICIPANTS: Randomized survey of 450 board-certified physicians in the United States from family medicine, general internal medicine, and otolaryngology. MAIN OUTCOME MEASURES: Responding physicians' use of diagnostic radiography as well as choice and duration of antimicrobial and adjunctive treatments of ABRS. RESULTS: Otolaryngologists were more likely to use supportive diagnostic radiography (P =.04). They were also more likely to treat patients with adjunctive therapy, such as topical decongestants (P =.01), guaifenesin (P =.01), and saline nasal irrigation (P =.01), in addition to antibiotics. Otolaryngologists prescribed more medications to treat patients with ABRS than primary care physicians (P =.01). There were no significant differences in diagnosis and management by family physicians and general internists. CONCLUSIONS: Otolaryngologists use more health care resources to diagnose and treat ABRS than primary care physicians despite an absence of evidence that such tests and treatments lead to better outcomes. Otolaryngologists typically treat a patient population with a higher prevalence of ABRS and frequently see referred patients with recurrent acute sinusitis and chronic rhinosinusitis, which may explain their tendency to treat patients more aggressively. Nevertheless, these survey results illustrate a lack of consensus within the medical community regarding the evaluation and management of community-acquired ABRS, suggesting that widely accepted evidence-based practice guidelines need to be developed.  相似文献   
995.
OBJECTIVE: The purpose of this pilot study was to document speech perception and localization abilities in patients who use a cochlear implant in one ear and a hearing aid in the other ear. DESIGN: We surveyed a group of 111 cochlear implant patients and asked them whether they used a hearing aid on their unimplanted ear. The first three patients who were available were tested on word and sentence recognition and localization tasks. Speech stimuli were presented from the front in quiet and in noise. In the latter conditions, noise was either from the front, the right, or the left. Localization was tested with noise bursts presented at 45 degrees from the right or left. In addition we asked the patients about their abilities to integrate the information from both devices. RESULTS: Speech perception tests in quiet showed a binaural advantage for only one of the three patients for words and none for sentences. With speech and noise both in front of the patient, two patients performed better with both devices than with either device alone. With speech in front and noise on the hearing aid side, no binaural advantage was seen, but with noise on the cochlear implant side, one patient showed a binaural advantage. Localization ability improved with both devices for two patients. The third patient had above-chance localization ability with his implant alone. CONCLUSIONS: A cochlear implant in one ear and a hearing aid in the other ear can provide binaural advantages. The patient who did not show a clear binaural advantage had the poorest hearing aid alone performance. The absolute and relative levels of performance at each ear are likely to influence the potential for binaural integration.  相似文献   
996.
997.
Limited evidence has suggested that low levels of circulating pyridoxal-5'-phosphate (PLP) may be associated with elevation of the inflammatory marker, C-reactive protein (CRP). We sought to determine whether the reported association of CRP with PLP was specific versus generalizable to other inflammation or hemostasis markers. Among 519 healthy middle aged adults in the Atherosclerosis Risk in Communities (ARIC) Study, we analyzed the cross-sectional relation of homocysteine, plasma and dietary B vitamin levels with multiple markers implicated in inflammation, endothelial dysfunction, or thrombogenesis: CRP, fibrinogen, white blood cell count, intracellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1), E-selectin, factor VIII, and von Willebrand factor. There was no significant association (P>0.05) of von Willebrand factor, I-CAM, or V-CAM with any of the plasma or dietary measures examined, and no marker was associated significantly with serum homocysteine. Contrary to our hypothesis, plasma PLP was not associated with CRP concentration. A higher white blood cell count was associated with lower B vitamin status (lower plasma PLP and folate, lower dietary B6 and B12), though not with use of vitamin supplements. In ostensibly healthy adults, B-vitamin status is not a strong correlate of circulating levels of inflammatory markers, cellular adhesion molecules, or thrombogenic factors.  相似文献   
998.
Oxidative stress is intimately involved in alcoholic cardiomyopathy. Catalase is responsible for detoxification of hydrogen peroxide (H(2)O(2)) and may interfere with ethanol-induced cardiac toxicity. To test this hypothesis, a transgenic mouse line was produced to overexpress catalase (~50-fold) in the heart, ranging from sarcoplasm, the nucleus and peroxisomes within myocytes. Mechanical and intracellular Ca(2+) properties were evaluated in ventricular myocytes from catalase transgenic (CAT) and wild-type FVB mice. Protein abundance of sarco (endo) plasmic reticulum Ca(2+)-ATPase (SERCA), phospholamban (PLB), Na(+)/Ca(2+) exchanger (NCX), dihydropyridine Ca(2+) receptor (DHPR), ryanodine receptor (RyR), Akt and phosphorylated Akt (pAkt) were measured by western blot. CAT itself did not alter body and organ weights, as well as myocyte contractile properties. Acute exposure of ethanol elicited a concentration-dependent depression in cell shortening and intracellular Ca(2+) in FVB mice with maximal inhibitions of 65.4% and 35.8%, respectively. The ethanol-induced cardiac depression was significantly attenuated in myocytes from CAT with maximal inhibitions of 42.4% and 27.3%. CAT also abrogated the ethanol-induced inhibition of maximal velocity of shortening/relengthening, prolongation of relengthening duration and intracellular Ca(2+) clearing time. Cell shortening at different extracellular Ca(2+) revealed stronger myocyte-shortening amplitude under lower (0.5 mM) Ca(2+) in CAT mice. Protein expression of NCX, RyR, Akt and pAkt were elevated in myocytes from CAT mice, while those of SERCA, PLB and DHPR were not affected. In conclusion, our data suggest that catalase overexpression may protect cardiac myocytes from ethanol-induced contractile defect, partially through improved intracellular Ca(2+) handling and Akt signaling.  相似文献   
999.
The brown recluse spider (Loxosceles reclusa) exists in significant populations mainly in the midwestern United States. Although bites can cause significant harm, envenomation is infrequent, and cases are usually clinically insignificant. Proper knowledge of the spider's habitat and lifestyle as well as the signs and symptoms of loxoscelism are needed to assess clinical cases adequately. Loxoscelism can masquerade as many serious pathologies, and vice versa, so it is important for the clinician to explore all possibilities in the differential diagnosis thoroughly. Treatments are controversial, and no conclusive test for envenomation is currently available. This review provides information to help physicians, especially in nonendemic areas, include or exclude brown recluse bite in the clinical diagnosis and provide proper care.  相似文献   
1000.
Many wheelchair users must travel in motor vehicles while seated in their wheelchairs. The safety features of seat assemblies are key to motor vehicle occupant crash protection. Seating system properties such as strength, stiffness, and energy absorbance have been shown to have significant influence on risk of submarining. This study investigated the effects of wheelchair seat stiffness and energy absorption properties on occupant risk of submarining during a frontal motor vehicle 20 g/30 mph impact using a validated computer crash simulation model. The results indicate that wheelchair-seating stiffness and energy absorption characteristics influence occupant kinematics associated with the risk of submarining. Softer seat surfaces and relatively high energy absorption/permanent deformation were found to produce pelvis excursion trajectories associated with increased submarining risk. Findings also suggest that the current American National Standards Institute/Rehabilitation Engineering and Assistive Technology Society of North America (ANSI/RESNA) WC-19 seating integrity may not adequately assess submarining risk.  相似文献   
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