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991.
Sunlight, cholesterol and coronary heart disease 总被引:9,自引:5,他引:4
Grimes DS; Hindle E; Dyer T 《QJM : monthly journal of the Association of Physicians》1996,89(8):579-589
We investigated the relationship between geography and incidence of
coronary heart disease, looking at deficiency of sunlight and thus of
vitamin D as a factor that might influence susceptibility and thus disease
incidence. Sunlight deficiency could increase blood cholesterol by allowing
squalene metabolism to progress to cholesterol synthesis rather than to
vitamin D synthesis as would occur with greater amounts of sunlight
exposure, and the increased concentration of blood cholesterol during the
winter months, confirmed in this study, may well be due to reduced sunlight
exposure. We show evidence that outdoor activity (gardening) is associated
with a lower concentration of blood cholesterol in summer but not in the
winter. We suggest that the geographical variation of coronary heart
disease is not specific, but is seen in other diseases and sunlight
influences susceptibility to a number of chronic diseases, of which
coronary heart disease is one.
相似文献
992.
993.
Barrier disruption in the major cerebral arteries after experimental subarachnoid hemorrhage in spontaneously hypertensive and normotensive rats 总被引:1,自引:0,他引:1
The effects of experimental subarachnoid hemorrhage (SAH) on the blood-arterial wall barrier in the major cerebral arteries were studied in 24 spontaneously hypertensive rats (SHR) and 13 Sprague-Dawley rats (SDR). Horseradish peroxidase (HRP) was given intravenously before killing the animals to assess the integrity of the barrier. In the acute experimental group, transient elevation of intracranial pressure (ICP) and systemic arterial pressure produced by cisternal injection of whole blood, saline solution, or Elliott's B solution resulted in extensive disturbance of the blood-arterial wall barrier. In the chronic group, only the cisternal injection of whole blood in SHR brought about an extensive and marked disturbance of the arterial permeability. These results suggest that: (a) early breakdown of the blood-arterial wall barrier seems to be due to a sudden rise in the ICP or arterial pressure; (b) in the chronic experiments, the subarachnoid clot is the most important factor responsible for the permeability changes; and (c) in the chronic SAH experiments, the blood-arterial wall barrier seems to be more vulnerable in SHR than in Sprague-Dawley rats. Due to the well-known similarities between SHRs and hypertensive human beings, patients with chronic hypertension should be considered at high risk after SAH for extensive blood-arterial wall barrier disturbances. 相似文献
994.
Underuse of screening mammography by family physicians 总被引:3,自引:0,他引:3
Although the American College of Radiology, the National Cancer Institute, and the American Cancer Society recommend screening mammography for women more than 40 years old, there is little compliance with these recommendations. Primary-care physicians are often reluctant to refer patients for the procedure, whereas the patients are usually willing to undergo the procedure. This survey documents the underuse of screening mammography by family physicians who are members of the Michigan Academy of Family Physicians. The underuse of mammography by this physician sample was due to two main factors: The physicians perceived far more disadvantages than advantages with mammography and perceived problems (with, e.g., equipment, effectiveness, and patient acceptance) as pervasive. To change the attitudes and referral behavior of family physicians, one must take into account the specific, negative perceptions of the procedure and place an emphasis on the initial referral, since subsequent referrals are easier to implement. 相似文献
995.
996.
The benefits of two dosing methods, patient-controlled analgesia (PCA) with morphine sulfate (MS) alone and PCA plus continuous infusion of morphine sulfate (PCA + CI) were clinically evaluated in a randomized, single-blinded study of 30 adult abdominal surgery patients. Doses were adjusted based on pain and sedation ratings. Respirations, pulse, blood pressure, pain and sedation ratings were assessed. Subjects rated their pain twice daily using a visual analog scale for 72 hr postoperatively. The subjects reported pain relief with both dosing regimens. No statistically significant differences between the groups were found in pain and sedation ratings, or length of time using the device, with the exception of a higher amount of MS used on postoperative day two by the infusion group (p less than 0.003). There seems to be a trend for the PCA + CI group to have less fluctuation in sedation between days and better pain control (as demonstrated by verbal and visual analog pain scores) on the third postoperative day. Statistical significance was not found, however. PCA plus continuous infusion of MS may be a beneficial approach to the management of postoperative pain in selected patients; studies to identify these patients need to be done. 相似文献
997.
The percutaneous absorption of 1% sulconazole nitrate in a cream formulation containing 3H-labeled drug has been studied in seven human subjects. Two applications of 4.5 g each were made to 450 cm2 of abdominal skin at 0 and 12 h, and the site was washed at 24 h. The application site was subsequently washed at 24-h intervals for 3 consecutive days, and 6.7% of the dose was recovered in the urine and 2.0% in the feces following a 7-d collection period. Radioactivity was detectable in the plasma from 8-96 h, with a peak occurring at 24 h, and could also be recovered in the skin wash up to 96 h after application. Total percutaneous absorption of sulconazole was estimated to be 8.7-11.3% of the applied dose, considerably more than that previously reported for other imidazole drugs. 相似文献
998.
W Y Cheng D N Ridinger C M Lehman R L Puryear L A Dethlefsen 《International journal of radiation biology》1989,56(4):463-483
The oxic radiation response (cytotoxicity) of two heterogeneous murine tumor-cell lines cultured in vitro was studied as a function of the cell's physiological state at the time of X-irradiation. The proliferating (P) 66 and 67 cells displayed equal radiosensitivities; however, the quiescent (Q) cells were considerably more radiosensitive than the P cells, and the 66Q cells were even more radiosensitive than the 67Q cells. Also, the 66Q cells continued to proliferate slowly with about 85 per cent in the G1 phase and 10 per cent in the S phase, while the 67 Q cells displayed a more complete G1 arrest (92-95 per cent). A detailed analysis of the metabolic status vs cell-cycle age (i.e. G1 vs S phase) indicated that the cell-cycle age was the predominant factor influencing radiation-induced cytotoxicity in 67 cells. The data also showed that in the plateau phase Q-cell cultures, pH and cell contact were not influencing factors and that the increased radiosensitivity of the Q cells could not be explained on the basis of energy deprivation. Moreover, the 66Q, but not the 67Q cells displayed an increased sensitivity in addition to that caused by the predominant cell-cycle age shift. This extra increase in radiosensitivity is of unknown metabolic origin, but could be related to cellular membrane fragility in the stressed 66Q cells since this extra component of Q-cell radiosensitivity was reduced both by refeeding (metabolic activation) 4 h before X-irradiation and by delayed plating while incubating the cells in Q medium at 37 degrees C after X-irradiation. 相似文献
999.
1000.
Revision surgery in clubfeet. 总被引:4,自引:0,他引:4
D Atar W B Lehman A D Grant A M Strongwater 《Clinical orthopaedics and related research》1992,(283):223-230
The reoperated clubfeet of 29 children aged one to 12 years were reviewed. The surgical procedure most often used in revision surgery was recomplete soft-tissue release alone or combined with plantar release, calcaneocuboid fusion, and capsulotomies of the navicular-first cuneiform-first metatarsal joint. In 27 of 29 feet, acceptable results were achieved. Nineteen were excellent and good results. An algorithm that suggests surgical solutions to a variety of clubfoot deformities in different age groups has been developed, as well as an objective rating system, to evaluate the long-term results of revision surgery of clubfeet. 相似文献