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91.
Regional left ventricular wall motion from first-pass radionuclide angiocardiography using an Anger camera. Experimental and clinical study. 下载免费PDF全文
S Walton E A Donaldson D J Rowlands R A Shields H J Testa C Wrigley 《Heart (British Cardiac Society)》1980,44(5):518-523
Experimental studies with a balloon phantom, and clinical studies were performed to evaluate first-pass radionuclide angiocardiography using a gamma camera in the assessment of regional wall motion. The phantom studies showed that choice of isocount contour was not critical in edge detection. Adequate count densities could be achieved, but only at the expense of temporal resolution. The clinical studies disclosed a good correlation with radiography in normal subjects and those with diffuse ventricular disease but a poor correlation in subjects with localised abnormalities of wall motion. 相似文献
92.
Zaman Vandana Shields Donald C. Shams Ramsha Drasites Kelsey P. Matzelle Denise Haque Azizul Banik Narendra L. 《Metabolic brain disease》2021,36(5):815-827
Metabolic Brain Disease - Parkinson’s disease (PD) is a neurodegenerative disorder etiologically linked to the loss of substantia nigra (SN) dopaminergic neurons in the mid-brain. The... 相似文献
93.
Peter S. Bernstein MD MPH James N. Martin MD Jr John R. Barton MD MS Laurence E. Shields MD Maurice L. Druzin MD Barbara M. Scavone MD Jennifer Frost MD Christine H. Morton PhD Catherine Ruhl CNM MS Joan Slager CNM DNP Eleni Z. Tsigas Sara Jaffer MPH M. Kathryn Menard MD MPH 《Journal of Midwifery & Women's Health》2017,62(4):493-501
Complications arising from hypertensive disorders of pregnancy are among the leading causes of preventable severe maternal morbidity and mortality. Timely and appropriate treatment has the potential to significantly reduce hypertension‐related complications. To assist health care providers in achieving this goal, this patient safety bundle provides guidance to coordinate and standardize the care provided to women with severe hypertension during pregnancy and the postpartum period. This is one of several patient safety bundles developed by multidisciplinary work groups of the National Partnership for Maternal Safety under the guidance of the Council on Patient Safety in Women's Health Care. These safety bundles outline critical clinical practices that should be implemented in every maternity care setting. Similar to other bundles that have been developed and promoted by the Partnership, the hypertension safety bundle is organized into four domains: Readiness, Recognition and Prevention, Response, and Reporting and Systems Learning. Although the bundle components may be adapted to meet the resources available in individual facilities, standardization within an institution is strongly encouraged. This commentary provides information to assist with bundle implementation. 相似文献
94.
Use of a commercial reagent leads to reduced germ tube production by Candida dubliniensis 总被引:3,自引:0,他引:3 下载免费PDF全文
The goal of this study was to determine the factor(s) explaining our inability to detect Candida dubliniensis. When germ tube-positive yeasts were tested for C. dubliniensis, no C. dubliniensis was detected; however, 58 C. dubliniensis strains were detected when germ tube-negative Candida albicans strains were tested further. Since all 58 C. dubliniensis strains detected were germ tube negative, these data implied that false-negative germ tube tests occurred with germ tube solution (GTS; Remel, Lenexa, KS). All 41 known C. dubliniensis strains tested were negative with GTS, whereas 40 were positive with rabbit serum (RS; Sigma-Aldrich, St. Louis, MO). Results for C. albicans were equivalent in GTS and RS. In conclusion, GTS cannot be used for the detection of C. dubliniensis, and switching from yeast to hyphae in C. dubliniensis is more restricted than in C. albicans. 相似文献
95.
96.
Lovell D Shields D Beck B Cuneo R McLellan C 《European journal of applied physiology》2012,112(9):3431-3437
The purpose of this study was to compare the cardiorespiratory response and mechanical efficiency (ME) of highly trained spinal cord injured (SCI) handcyclists with untrained SCI men. Ten trained handcyclists (≥ 2 years training) and ten untrained but physically active SCI men completed an incremental exercise test to exhaustion and a sub-maximal test (50 and 80 W) on an electromagnetically braked arm ergometer. The trained participants completed a questionnaire on their training and race performance over the past year, including average training volume (in kilometers), number of training sessions per week and best 20-km time trial. The trained SCI men had higher VO2 peak, peak power (p ≤ 0.001) and peak heart rate (p = 0.021) compared to the untrained SCI men. The trained men had higher (p ≤ 0.001) ME at 50 W (14.1 ± 2.0%) and 80 W (17.2 ± 2.6) compared to the untrained men (50 W; 12.5 ± 1.8 and 80 W; 15.7 ± 2.1). Peak power (r = -0.87, p = 0.001), VO2 peak (r = -0.67, p = 0.033) and ME (r = -0.58, p = 0.041) were negatively correlated with the participants best 20-km time trial. Multiple linear regression indicated peak power (p < 0.001) and VO2 peak (p = 0.021) were the best predictors (87%) of 20-km time trial performance. Highly trained SCI handcyclists have a greater aerobic capacity and ME compared to untrained SCI, and are able to reach their maximum age-predicted heart rate during an incremental exercise test. The best predictor of 20 km race performance in highly trained SCI handcyclists is peak power attained during an incremental exercise test. 相似文献
97.
Gysland SM Mihalik JP Register-Mihalik JK Trulock SC Shields EW Guskiewicz KM 《Annals of biomedical engineering》2012,40(1):14-22
Concussions sustained during college and professional football careers have been associated with both acute and chronic neurologic
impairment. The contribution of subconcussive impacts to this impairment has not been adequately studied. Therefore, we investigated
the relationship between subconcussive impacts and concussion history on clinical measures of neurologic function. Forty-six
collegiate football players completed five clinical measures of neurologic function commonly employed in the evaluation of
concussion before and after a single season. These tests included the Automated Neuropsychological Assessment Metrics, Sensory
Organization Test, Standardized Assessment of Concussion, Balance Error Scoring System, and Graded Symptom Checklist. The
Head Impact Telemetry (HIT) System recorded head impact data including the frequency, magnitude, and location of impacts.
College football players sustain approximately 1,000 subconcussive impacts to the head over the course of a season, but for
the most part, do not demonstrate any clinically meaningful changes from preseason to postseason on measures of neurologic
function. Changes in performance were mostly independent of prior concussion history, and the total number, magnitude and
location of sustained impacts over one season as observed R
2 values ranged between 0.30 and 0.35. Repetitive subconcussive head impacts over a single season do not appear to result in
short-term neurologic impairment, but these relationships should be further investigated for a potential dose–response over
a player’s career. 相似文献
98.
Iguchi M Littmann AE Chang SH Wester LA Knipper JS Shields RK 《Journal of Athletic Training》2012,47(2):184-190
Context:
Conditions such as osteoarthritis, obesity, and spinal cord injury limit the ability of patients to exercise, preventing them from experiencing many well-documented physiologic stressors. Recent evidence indicates that some of these stressors might derive from exercise-induced body temperature increases.Objective:
To determine whether whole-body heat stress without exercise triggers cardiovascular, hormonal, and extra-cellular protein responses of exercise.Design:
Randomized controlled trial.Setting:
University research laboratory.Patients or Other Participants:
Twenty-five young, healthy adults (13 men, 12 women; age = 22.1 ± 2.4 years, height = 175.2 ± 11.6 cm, mass = 69.4 ± 14.8 kg, body mass index = 22.6 ± 4.0) volunteered.Intervention(s):
Participants sat in a heat stress chamber with heat (73°C) and without heat (26°C) stress for 30 minutes on separate days. We obtained blood samples from a subset of 13 participants (7 men, 6 women) before and after exposure to heat stress.Main Outcome Measure(s):
Extracellular heat shock protein (HSP72) and catecholamine plasma concentration, heart rate, blood pressure, and heat perception.Results:
After 30 minutes of heat stress, body temperature measured via rectal sensor increased by 0.8°C. Heart rate increased linearly to 131.4 ± 22.4 beats per minute (F6,24 = 186, P < .001) and systolic and diastolic blood pressure decreased by 16 mm Hg (F6,24 = 10.1, P < .001) and 5 mm Hg (F6,24 = 5.4, P < .001), respectively. Norepinephrine (F1,12 = 12.1, P = .004) and prolactin (F1,12 = 30.2, P < .001) increased in the plasma (58% and 285%, respectively) (P < .05). The HSP72 (F1,12 = 44.7, P < .001) level increased with heat stress by 48.7% ± 53.9%. No cardiovascular or blood variables showed changes during the control trials (quiet sitting in the heat chamber with no heat stress), resulting in differences between heat and control trials.Conclusions:
We found that whole-body heat stress triggers some of the physiologic responses observed with exercise. Future studies are necessary to investigate whether carefully prescribed heat stress constitutes a method to augment or supplement exercise. 相似文献99.
Shields Brown Stevenson Fitch Schock Turner Taylor & Ennis 《Clinical and experimental allergy》1999,29(10):1382-1389
BACKGROUND: Serum eosinophilic cationic protein (ECP) concentrations may be useful noninvasive markers of airways inflammation in atopic asthma. However, the usefulness of serum ECP measurement for the prediction of airways inflammation in children with a history of wheezing is unknown. OBJECTIVE: To determine the test accuracy of serum ECP and blood eosinophil percentage as noninvasive markers of eosinophilic airways inflammation. METHODS: Bronchoalveolar lavage (BAL) fluid and peripheral blood samples for eosinophil percentages and serum ECP were obtained from children undergoing elective surgery and who gave a history of wheezing in the previous year. Sensitivity, specificity and likelihood ratios (LH) and the area under the curve (AUC) for the receiver operator characteristic (ROC) curve were calculated for each blood marker for the prediction of airways inflammation defined by a BAL eosinophil percentage > 0.86. Data were analysed on the basis of how recently symptoms had occurred. RESULTS: Seventy-seven children (median age 6.75 years) were studied. An AUC of 0.75 (log serum ECP concentration) and 0.76 (log blood eosinophil percentage) was obtained for predicting airways inflammation. A serum ECP > 13 microg/L yielded a LH of 4.4, whereas using a cutoff blood eosinophils > 4% yielded a LH of 1.9, for the prediction of elevated eosinophils in BAL. Serum ECP and eosinophil percentages in BAL and blood were lowest (not statistically significant) when last symptoms had occurred more than 12 weeks previously. CONCLUSIONS: Serum ECP and blood eosinophil percentages are useful markers for predicting eosinophilic airways inflammation in wheezing children. 相似文献
100.
Although telomere dysfunction is a characteristic of breast cancer cells, the relationship between deficiency on individual chromosomal telomeres in normal somatic cells and breast cancer risk has not been characterized. A case-control study was conducted to examine the associations between individual lengths of 92 telomeres in the human genome and the risk of breast cancer in 204 newly diagnosed breast cancer patients and 236 healthy controls. Chromosome arm-specific telomere lengths were measured by telomere quantitative fluorescent in situ hybridization. Unconditional logistic regression was used to estimate the risk associations. This genome-wide screen identified that shorter telomere lengths on chromosomes Xp and 15p were associated with breast cancer risk in pre-menopausal women, with adjusted odds ratios (aORs) of 2.5 (95% CI = 1.3, 4.8) and 2.6 (1.3, 5.0), respectively. The study also revealed that greater length differences between homologous telomeres on chromosomes 9p, 15p and 15q were associated with breast cancer risk in pre-menopausal women, with aORs of 4.6 (2.3, 9.2), 3.1 (1.6, 6.0) and 2.8 (1.4, 5.4), respectively. When the subjects were categorized into quartiles, a dose-response relationship was observed for all of the above telomeres (P-for-trend ≤ 0.005). This study revealed that telomere deficiencies on chromosomes 9p, 15p, 15q and Xp were associated with breast cancer risk in pre-menopausal women. If confirmed in future studies, chromosomal arm-specific telomeres are likely to be a useful panel of blood-based biomarkers for breast cancer risk assessment, given their strong associations with breast cancer risk. 相似文献