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991.
992.
Decisions must be made rapidly in the field when assessing trauma patients. Acronyms, such as ESCAPE, can help you remember important facts and aid your assessment. The important thing to remember about the MAPP system is that a score is assigned only after you evaluate patient and scene circumstances. The next time you meet a shell master, spend some time figuring out his system and beat him at his own game. But don't play guessing games with trauma victims. Use a systematic approach to quickly assess your trauma patients and determine the need to transport them to a trauma center.  相似文献   
993.
Actinomycosis is nowadays a not very common festered chronic infection. Cervicofacial actinomycosis is the most frequent clinical form, and it is due in most cases to Actinomyces israelii. Thyroid actinomycosis has been scarcely described in the literature. The lesions, that are characterized to be notably indurated and to contain multiple abscesses that drain to the surface through sinus tracts, frequently simulate other infective clinical entities and often neoplasms, therefore the diagnosis is delayed in the time. From a case of thyroid actinomycosis diagnosed and treated in our service which was initial diagnosed as a thyroid neoplasm, we revise the cases described in the literature and we make a point in the difficulty to arrive to the diagnosis of this entity.  相似文献   
994.
BACKGROUND: A system was established to examine the extent to which the apheresis donor determines platelet recovery after transfusion, to measure the impact of ABO identity, and to predict outcome by evaluating the donor. STUDY DESIGN AND METHODS: The percentage of platelet recovery was measured after prophylactic transfusion of apheresis units divided from single donors to paired recipients with uncomplicated thrombocytopenia secondary to leukemia chemotherapy. Platelet microaggregation induced by citrate was measured at the time of apheresis. RESULTS: Platelet recoveries in paired recipients correlated strongly when both transfusions were ABO- identical. When one recipient was ABO-identical and the other was ABO-nonidentical, nonidentical transfusions yielded one-third the recovery of ABO-identical transfusions. In ABO-identical transfusions, platelet recovery in donors having microaggregates in the before-apheresis ACD sample was one-third that in donors without microaggregates. This difference was observed at 1 and 24 hours. Expression of P-selectin in the apheresis units at the time of transfusion correlated well with ACD microaggregates in the before-apheresis sample. CONCLUSION: When transfusions of platelets are ABO-identical, donor quality dominates recovery in circulation. Donor quality is predicted by a rapid and simple assay of citrate-induced microaggregation performed at the time of apheresis. When donor quality is factored out, ABO identity prevails.  相似文献   
995.
996.
BACKGROUND: Little information is available on the assessment of changes in body composition as a function of weight change with the use of the fan beam of dual-energy X-ray absorptiometry (DXA). OBJECTIVE: The objective was to determine the accuracy of the fan beam of the QDR 4500A densitometer and the pencil beam of the QDR 2000 densitometer in estimating changes in whole-body lean soft tissue mass (LSTM(DXA)) and fat mass (FM) with weight change. DESIGN: Thirty-seven subjects who lost 5.7 +/- 4.5 kg were measured before and after weight change. Using total body water and computed tomography (CT) of the midthigh, we compared changes in FFM(TBW) and LSTM(CT) with changes in LSTM(DXA). RESULTS: Overall, compared with TBW, the fan beam gave a larger estimate of change (macro x +/- SD) in LSTM (fan beam - TBW: -0.7 +/- 1.6 kg) than did the pencil beam (pencil beam - TBW: -0.1 +/- 1.6 kg). When the change in LSTM obtained with the fan beam and pencil beam was regressed against the change in FFM(TBW), the slope of the line for the fan beam was 0.97 (r(2) = 0.61) and that for the pencil beam was 0.86 (r(2) = 0.61). Regression analysis showed that the results between the 2 units were not interchangeable. For the midthigh region, the change in LSTM(CT) was moderately correlated with the change in LSTM(DXA) with the fan beam and pencil beam. CONCLUSIONS: The measurement of change in LSTM with the fan and pencil beams provides the same relation to changes in FFM assessed by TBW, but the 2 systems are not interchangeable.  相似文献   
997.
DEET and permethrin were implicated in the development of illnesses in some veterans of the Persian Gulf War. This study was designed to investigate the effects of daily dermal application of these chemicals, alone or in combination, on the permeability of the blood-brain barrier (BBB) and blood-testes barrier (BTB) and on sensorimotor performance in male Sprague-Dawley rats. Groups of five rats were treated with a dermal daily dose of 4, 40, or 400 mg/kg DEET in ethanol or 0.013, 0.13, or 1.3 mg/kg permethrin in ethanol for 60 d. A group of 10 rats received a daily dermal dose of ethanol and served as controls. BBB permeability was assessed by injection of an iv dose of the quaternary ammonium compound [3H]hexamethonium iodide. While permethrin produced no effect on BBB permeability, DEET alone caused a decrease in BBB permeability in brainstem. A combination of DEET and permethrin significantly decreased the BBB permeability in the cortex. BTB permeability was decreased by treatment with DEET alone and in combination with permethrin. The same animals underwent a battery of functional behavior tests 30, 45, and 60 d after exposure to evaluate their sensorimotor abilities. All treatments caused a significant decline in sensorimotor performance in a dose- and time-dependent manner. These results show that daily dermal exposure to DEET, alone or in combination with permethrin, decreased BBB permeability in certain brain regions, and impaired sensorimotor performance.  相似文献   
998.
BACKGROUND: In Mexico, scorpion poisoning is a health problem because the poison has beta toxins that affect sodium channel activation. Lidocaine decreases ion permeability across the sodium channel acting in the opposite manner. The aim of this work is to determine whether lidocaine antagonized the toxic effect of the crude poison of Centruroides limpidus limpidus. METHODS: One half the lethal dose of the crude poison was determined alone and in the presence of different doses of lidocaine. Experiments with crude poison at LD(50) and crude poison plus lidocaine were carried out after 30, 90, and 180 min of poison inoculation; lung, heart, and brain were obtained for histopathologic analysis. RESULTS: Lidocaine (7 mg/kg dose) increased LD(50) of crude poison (2.95 +/- 0.22 to 6.68 +/- 0.25, p <0.001). Intraalveolar hemorrhage at 30, 90, and 180 min, myocardial edema, and brain congestion at 90 min were significantly reduced (p <0.05). CONCLUSIONS: Lidocaine exerts a protective effect against toxicity of the crude poison of Centruroides limpidus limpidus, probably by its antagonist activity on the sodium channel.  相似文献   
999.
The authors used the induced exposure method to compare risks of traffic crashes among different types of Spanish drivers under different environmental conditions. The authors analyzed traffic crashes recorded by the Spanish Dirección General de Tráfico for the years 1991 and 1992 to compare proportions of drivers in different age/sex categories who were involved in single-vehicle and multivehicle crashes under different psychological and physical conditions. Crash risk was 1.42- to 2.35-fold greater in men than in women, depending on driver category and environmental factors. Risk was also significantly higher in the 18- to 24-year-old age group (1.75- to 2.87-fold greater than in drivers aged 25-49 years) and under abnormal psychological-physical conditions (1.69- to 4.10-fold greater among drivers under the influence of alcohol). Twilight and night driving, driving in urban areas, and driving on weekends and legal holidays were also associated, though nonsignificantly, with a slightly higher traffic crash risk. These findings are consistent with earlier reports, and they support the usefulness of the induced exposure method as an easy and economical tool with which to analyze data contained in traffic crash records.  相似文献   
1000.
We report the case of a squizoid 45 year old man who presented an acute urinary retention and had several foreign bodies in the urethra and bladder.  相似文献   
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