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James B. Derr John A. Clark Maryann Morales Eli M. Espinoza Sandra Vadhin Valentine I. Vullev 《RSC advances》2020,10(41):24419
This article reports two discoveries. (1) 2-Methoxyethanol induces unprecedented selectivity for etherification of 5-hydroxy-2-nitrobenzic acids without forming undesired esters. (2) Such compounds are precursors for amides showing unusual robustness against oxidative degradation, essential for molecular electrets that transfer strongly oxidizing holes at about −6.4 eV vs. vacuum.Selective etherification produces precursors for amides resistant to oxidative degradation, i.e., showing reversible oxidation at 1.5 to 1.7 V vs. SCE. 相似文献
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We have benefited from using a simple, time-saving radiographic procedure for more than 5 years which may establish a correct diagnosis in most patients with clinically suspected, but initially occult, hip fractures. 相似文献
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Mari Eli Leonelli de Moraes Luiz Cesar de Moraes Mayra Cardoso Weber Ursi Sergio Lucio Pereira de Castro Lopes 《Research in developmental disabilities》2013,34(11):4274-4279
It is important to estimate both chronological age (CA) and maturational age of an individual, in order to perform orthopedic treatment or surgery, and in cases of lost documentation. Use of dental age (DA) for these purposes has been widely studied; however, the literature is scarce with regard to individuals with Down syndrome (DS), a prevalent condition worldwide. In this study the chronology of dental maturation was evaluated by analyzing the DA of individuals with DS based on the Chronological Mineralization Table proposed by Nolla (1960). Thus, second molars were evaluated in 57 panoramic radiographs of male and female individuals with DS, between 5 and 16 years-old. These data were compared with a control group of 191 nonsyndromic individuals of the same age group. Correlation between CA and DA was ascertained using Pearson's correlation coefficient (r), and the difference between these variables was measured using Student's t-test for paired samples and the method proposed by Bland and Altman. The difference between DA and CA was compared between the control and DS groups using Student's t-test for independent samples (α = 0.05). DA was slightly lower than the CA; however, this difference was only significant for females. The difference between DA and CA was not significant between individuals with DS and control group (both genders, p = 0.945; males, p = 0.542; females, p = 0.381). We concluded that dental maturation in individuals with DS occurs similarly to that of nonsyndromic individuals. 相似文献
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Royce W. Woodroffe Eli A. Perez Scott C. Seaman Brian J. Park Russ P. Nockels Matthew A. Howard Saul Wilson 《Neuromodulation》2022,25(5):775-782
ObjectiveSpinal cord stimulation (SCS) has become a popular nonopioid pain intervention. However, the treatment failure rate for SCS remains significantly high and many of these patients have poor sagittal spinopelvic balance, which has been found to correlate with increased pain and decreased quality of life. The purpose of this study was to determine if poor sagittal alignment is correlated with SCS treatment failure.Materials and MethodsComparative retrospective analysis was performed between two cohorts of patients who had undergone SCS placement, those who had either subsequent removal of their SCS system (representing a treatment failure cohort) and those that underwent generator replacement (representing a successful treatment cohort). The electronic medical record was used to collect demographic and surgical characteristics, which included radiographic measurements of lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), and sacral slope (SS). Also included were data on pain medication usage including opioid and nonopioid therapies.ResultsEighty-one patients met inclusion criteria, 31 had complete removal, and 50 had generator replacements. Measurement of sagittal balance parameters demonstrated that many patients had poor alignment, with 34 outside normal range for LL (10 vs 24 in removal and replacement cohorts, respectively), 30 for PI (12 [38.7%] vs 18 [36.0%]), 46 for PT (18 [58.1%] vs 28 [56.0%]), 38 for SS (18 [58.1%] vs 20 [40.0%]), and 39 for PI-LL mismatch (14 [45.2%] vs 25 [50.0%]). There were no significant differences in sagittal alignment parameters between the two cohorts.ConclusionsThis retrospective cohort analysis of SCS patients did not demonstrate any relationship between poor sagittal alignment and failure of SCS therapy. Further studies of larger databases should be performed to determine how many patients ultimately go on to have additional structural spinal surgery after failure of SCS and whether or not those patients go on to have positive outcomes. 相似文献
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Anaphylaxis in the pediatric population is both serious and potentially lethal. The incidence of allergic and anaphylactic reactions has been increasing and the need for life saving intervention with epinephrine must remain an important part of Emergency Medical Services (EMS) provider training. Our aim was to characterize dosing and timing of epinephrine, diphenhydramine, and albuterol in the pediatric patient with anaphylaxis. In this retrospective chart review, we studied prehospital medication administration in pediatric patients ages 1 month up to 14 years old classified as having a severe allergic reaction or anaphylaxis. We compared rates of epinephrine, diphenhydramine, and albuterol given to patients with allergic conditions including anaphylaxis. In addition, we calculated the rate of epinephrine administration in cases of anaphylaxis and determined what percentage of time the epinephrine was given by EMS or prior to their arrival. Of the pediatric patient contacts, 205 were treated for allergic complaints. Of those with allergic complaints, 98 of 205 (48%; 95% CI 41%, 55%) had symptoms consistent with anaphylaxis and indications for epinephrine. Of these 98, 53 (54%, 95% CI 44%, 64%) were given epinephrine by EMS or prior to EMS arrival. Among the patients in anaphylaxis not given epinephrine prior to EMS arrival, 6 (12%; 95% CI 3%, 21%) received epinephrine from EMS, 10 (20%; 95% CI 9%, 30%) received diphenhydramine only, 9 (18%, 95% CI 7%–28%) received only albuterol and 17 (33%, 95% CI 20%–46%) received both albuterol and diphenhydramine. 9 patients in anaphylaxis received no treatment prior to arriving to the emergency department (18%, 95% CI 7%–28%). In pediatric patients who met criteria for anaphylaxis and the use of epinephrine, only 54% received epinephrine and the overwhelming majority received it prior to EMS arrival. EMS personnel may not be treating anaphylaxis appropriately with epinephrine. 相似文献
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