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61.
M S Levine 《Radiologic clinics of North America》1987,25(1):79-91
Involvement of the upper gastrointestinal tract by Crohn's disease is being recognized with increasing frequency. Gastroduodenal disease is more common, although esophageal disease is now noted infrequently as well. There is nearly always concomitant involvement of the small bowel or colon. Initial phases of the disease are manifested as superficial inflammatory changes of the mucosa but can progress to scarring and stenosis. Optimum double-contrast technique is necessary to detect these early lesions. 相似文献
62.
Dr Robert M. Lynd-Stevenson Stuart Byrne Sue Dolman Michael Harrison Brian Williams 《Clinical Psychologist》2007,11(2):45-49
The present paper outlines the development and evaluation of an allocation committee to distribute community placements on an equitable basis between universities. Although based on our experience in South Australia with the University Placement Allocation Committee (UPAC), the primary goal is to outline the steps that would be useful if placement coordinators at other universities in Australia decided to establish and maintain an allocation committee. A survey of field supervisors was also conducted and field supervisors endorsed UPAC as a constructive mechanism for allocating community placements. 相似文献
63.
Mark A Klebanoff Richard J Levine John D Clemens Diana G Wilkins 《American journal of epidemiology》2002,155(1):32-37
To determine whether the third-trimester maternal serum concentration of paraxanthine, caffeine's primary metabolite, is associated with delivery of a small-for-gestational age infant (birth weight less than the 10th percentile for gestational age, gender, and ethnicity) and whether this association differs by smoking, the authors studied 2,515 women who participated in the Collaborative Perinatal Project from 1959 to 1966. The women provided a third-trimester serum sample and had been controls for a nested case-control study of spontaneous abortion. The mean serum paraxanthine concentration was greater in women who gave birth to small-for-gestational age infants (754 ng/ml) than to appropriately grown infants (653 ng/ml, p = 0.02). However, the linear trend for increasing serum paraxanthine concentration to be associated with increasing risk of small-for-gestational age birth was confined to women who also smoked (p = 0.03). There was no association between paraxanthine and fetal growth in nonsmokers (p = 0.48). Adjustment for maternal age, pre-pregnant weight, education, parity, ethnicity, and the number of cigarettes smoked per day did not alter the results substantially, although the p value for trend among smokers increased to 0.07. The authors conclude that maternal third-trimester serum paraxanthine concentration, which reflects caffeine consumption, was associated with a higher risk of reduced fetal growth, particularly among women who smoked. 相似文献
64.
The effects of captopril, methyldopa, and propranolol were assessed for sense of well-being and vitality among 626 men with mild to moderate hypertension in a multicenter, randomized, double-blind clinical trial. After a 24-week treatment period, patients taking captopril, compared with patients taking methyldopa and propranolol, scored significantly higher on measures of well-being and vitality. In addition, patients on captopril had more favorable results in being able to keep up with their work and in not feeling tired or sleepy at work. The effects of each of the drugs manifested themselves at different periods. For example, the negative effects of methyldopa on vitality were evident by week 8, whereas the negative effects did not become manifest for propranolol until week 24. On the other hand, a steady progressive improvement in vitality scores was evident at week 8 and at week 24 for patients on captopril. The findings of the study also suggest that the effects of the treatment drugs were most marked in patients who had had previous antihypertensive medications and who were on single-drug therapy during the course of the clinical trial. Further, the differences between patients taking captopril and those on methyldopa and propranolol appear to be obscured by the addition of a diuretic. The findings of the study may guide the physician in orienting his or her patient and in planning and implementing a therapeutic regimen. 相似文献
65.
One hundred forty-three patients with 163 upper extremity vascular injuries were reviewed. Penetrating trauma accounted for 94% of the injuries and blunt trauma for 6%. Absent pulses are not a completely reliable sign of upper extremity arterial injury. The most frequently injured upper extremity vessel is the brachial artery, followed in decreasing frequency by ulnar, radial, and axillary arterial injuries and axillary venous injuries. The most common technique of vascular repair was end-to-end anastomosis, followed by vein graft interposition. No amputations were required. Despite excellent results of vascular reconstruction, functional impairment due to associated nerve injuries was a distressingly predominant finding. 相似文献
66.
Caring for a patient with Alzheimer's disease produces significant stress and morbidity in the caregiver. This article reviews the existing evidence on caregiver burden in Alzheimer's disease and elaborates on the counseling and legal options that can be exercised by them. By availing of existing supports and planning ahead, caregivers can decrease burden levels and deliver more effective care to the patient. 相似文献
67.
A large pediatric residency program conducted an extensive analysis of the reliability and validity of the rating forms used to evaluate the pediatric residents enrolled in the program. Analyses were conducted on groups of residents who took the Pediatric In-Training Program (PITE) from 1977 through 1981. An average of 7.1 faculty members rated each resident on a standard form. The data indicate that although the reliability of individual ratings is very low, several factors achieved acceptable levels of reliability when aggregated. The first-year rating of history-taking ability correlated significantly with the PITE but ratings for more advanced residents did not correlate with PITE scores, mostly because of ceiling effects. 相似文献
68.
Galega officinalis L (goatsrue), a plant introduced from Europe and found in abundance in northern Utah, was tested for toxicity in ewes (Ovis aries). Clinical signs of poisoning induced by doses as small as 0.8 g of dried plant/kg body weight/day included dyspnea, anoxia, and foaming nasal discharge. Pathologic signs in animals that died following overdose of the plant included severe hydrothorax, generalized lung congestion, foamy exudate in bronchioles and trachea, epicardial and endocardial petechiation, and pericardial effusion in severely affected ewes. Microscopic lesions included a severe diffuse alveolar and interlobular edema. No significant alterations in blood constituents were observed in treated animals. Ewes administered the plant on several consecutive days developed an apparent adaptation to the toxin of the plant and were thereby able subsequently to tolerate levels 5-10 times the pre-treatment lethal dose with no discernible adverse clinical or pathological effects. 相似文献
69.
Clinical practice guidelines for the care and treatment of breast cancer: Mastectomy or lumpectomy? The choice of operation for clinical stages I and II breast cancer (summary of the 2002 update) 总被引:1,自引:0,他引:1
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70.
Stuart J. McLachlan John C. Francisco Joseph R. Pernicone Anton N. Hasso 《Journal of magnetic resonance imaging : JMRI》1994,4(3):405-411
A phase III multicenter study was conducted in 89 patients with known intracranial vascular lesions to evaluate an extracellular gadolinium contrast agent, gadoteridol, for intracranial magnetic resonance (MR) angiography. The pre- and postcontrast MR angiograms of 82 patients were evaluated by the unblinded investigators and by two blinded readers (A and B) for visualization of lesions; arterial and venous anatomy; extent, size, and number of lesions; and disease classification. The unblinded readers indicated that lesions were visualized better on postcontrast images in the following categories: venous anatomy, 87 (81%) of 107 lesions; arterial anatomy, 43 lesions (40%); and extent or size of lesions, 38 lesions (36%). In 29 (35%) of 82 patients, the unblinded readers determined that enhanced MR angiography provided more diagnostic information than unenhanced MR angiography. The blinded readers determined that enhanced MR angiography provided more information for visualization of vascular anatomy in more than 60% of cases. The additional information provided with gadoteridol would have changed the diagnosis in nine (8%) of 107 lesions seen by the unblinded readers, 11 (12%) of 90 lesions seen by reader A, and three (3%) of 93 lesions seen by reader B. The results confirm that the use of gadoteridol improves the visualization of intracranial vascular lesions with MR angiography. The authors conclude that development of new postprocessing algorithms will improve the utility of contrast-enhanced MR angiography. 相似文献