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31.
This study assessed the impact of family history of alcoholism and antisocial behavior on problem drinking among male first-time DWI offenders. A sample of 123 men in DWI classes were assessed on demographic factors, antisocial behavior and family history of alcoholism. Also, measures of current and past drinking problems were assessed, including scales of perceived ability to control consumption, degree of physical dependence, occurrence of alcohol-related problems and preoccupation with alcohol. The results indicated that while family history of alcohol and antisocial behavior were not significantly related to quantity/frequency of alcohol consumption or alcohol-related problems, family history was related to drink duration. Main effects of family history and antisocial behavior were found for preoccupation with alcohol and physical dependence. There was a significant interaction with respect to perceived ability to control drinking. Results are discussed with regard to the implication that family history of alcoholism and antisocial behavior may influence the development of important precursors to alcoholism. 相似文献
32.
Elsa Murray Ph.D. Estralita Martin Douglas Burton Leonard J. Deftos 《Journal of bone and mineral research》1989,4(6):831-838
Biochemical and molecular biological studies of osteoblastic cell function and hormonal regulation are frequently confounded by the inherent cellular heterogeneity and phenotypic instability of existing in vitro and in vivo model systems. A new technique (derived from Western blotting or antibody-based detection of protein molecules bound to nitrocellulose paper) is described for identification of individual cells which synthesize osteoblast-specific gene products (bone Gla-protein, type I collagen, and alkaline phosphatase) or produce cAMP in response to parathyroid hormone (PTH) or isoproterenol. Dispersed primary neonatal rat calvariae or osteogenic sarcoma cells were “plated” on Immobilon-P (a hydrophobic transfer membrane with very high protein-binding capacity) for 30 minutes to several hours, followed by agonist treatment, formalin fixation, hematoxylin staining, and immunostaining with a battery of antibodies specific for osteoblastic products. Individual cells and their secretory zones were visualized by light microscopy and counted. Treatment with PTH with or without isoproterenol resulted in increases in the percentages of osteoblastic cells elaborating cAMP, as well as the intensity of immunostaining, but had no effects on MCF-7 cells, a nonosteoblastic breast carcinoma control line. The percentage of cells within each primary osteoblastic cell population isolated or rat osteogenic sarcoma cell clone (G2 or C12) that elaborated bone-specific proteins or that generated cAMP in response to PTH varied with time and the individual cellular preparation, reconfirming the cellular heterogeneity of these systems. This method, in conjunction with techniques such as in vitro hybridization, should prove useful in characterizing discrete osteoblastic bone cell subpopulations and in clarifying mechanisms of hormonal regulation by local and systemic agents. 相似文献
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Edouard J. Trabulsi MD William G. Merriam MD Leonard G. Gomella MD 《Current Prostate Reports》2006,4(2):67-72
Correct staging of prostate cancer at initial diagnosis, as well as accurate staging and tumor localization with biochemical recurrence, remains generally inaccurate with current imaging techniques. Newer modalities are being investigated to accurately identify patients with prostate cancer at different stages of disease. Identification of locally recurrent disease or distant metastasis at the time of biochemical failure after local therapy will help guide treatment options and avoid potentially toxic salvage therapies in patients who will not benefit. A review of prostate cancer imaging literature over the past 12 months was performed to identify emerging imaging modalities that may be beneficial in the management of prostate cancer. Enhanced transrectal ultrasonography modalities, including ultrasound contrast agents, color and power Doppler, and elastrography, have demonstrated incremental benefit when combined with standard grayscale ultrasonography to accurately target and diagnose prostate cancer. Endorectal MRI, with contrast enhancement and spectroscopic imaging, shows promise in the initial staging of prostate cancer prior to local therapy. The use of positron-emission tomography scan for prostate cancer remains to be defined, but may help delineate the site of recurrence with biochemical failure after local therapy. Several new imaging modalities show promise for the evaluation of the patient with prostate cancer. Enhanced ultrasonography techniques may prove to be more accurate in diagnosing prostate cancer over standard gray-scale ultrasonography. Accumulating evidence supports the use of endorectal MRI and spectroscopy to help treatment planning with either surgical or radiotherapeutic approaches. Although intriguing, the available data for positron-emission tomography in prostate cancer remains too shallow to advocate routine use. 相似文献
36.
J D Brust B J Leonard A Pheley W O Roberts 《American journal of diseases of children (1960)》1992,146(6):741-747
OBJECTIVE--To determine the rate, type, and severity of injuries to child hockey players as well as assessing coaches', parents', and players' attitudes and knowledge of hockey. DESIGN--A prospective observation of a population's injuries using injury-reporting forms and surveys. SETTING--A community-organized hockey program in Minnesota. PARTICIPANTS: One hundred fifty boys, aged 9 through 15 years, who played ice hockey during the 1990-1991 winter season. MEASUREMENTS AND MAIN RESULTS--Injuries were reported by multiple observers, including coaches, managers, and trained independent observers at the time an injury occurred; coaches, parents, and players were surveyed regarding hockey injuries, knowledge, and attitudes. One in three players experienced an injury during the season. The most common injuries were contusions. Six of 100 players experienced injuries severe enough to require cessation of physical activities for 8 to 25 days or longer. Weight differences of 53 kg and height differences of 55 cm were reported between Bantam-aged players (13 through 15 years), and body contact, including legal checks, accounted for 86% of injuries during games. Illegal checks and violations were associated with 66% of injuries during games, yet only four penalties (14%) were assessed. In addition, one in three games in which an injury resulted was described as hostile and 15% of the injuries were considered intentional. CONCLUSIONS--Eliminating violence and body checking for prepubertal boys while emphasizing rule enforcement and good sportsmanship are recommended. 相似文献
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38.
Semipermeable Hollow Fiber Membranes in Hepatocyte Bioreactors: A Prerequisite for a Successful Bioartificial Liver? 总被引:10,自引:0,他引:10
Leonard M. Flendrig Anje A. te Velde Robert A.F.M. Chamuleau 《Artificial organs》1997,21(11):1177-1181
Abstract: Recent studies have shown that liver support systems based on viable hepatocytes can prolong life in animal models of acute liver failure. Now the time has come to elucidate the design characteristics that are essential to construct an efficient bioreactor. The gold standard remains the intact liver. Despite the very high cell density in this organ, individual cell perfusion is guaranteed resulting in low diffusional gradients which are essential for optimal mass transfer. These conditions are not met in bioreactors based on hollow fiber membranes. Moreover, the semipermeable membranes can foul and act as a diffusional barrier between the hepatocytes and the blood or plasma of the recipient. We devised a novel bioreactor for use as a bioartificial liver that does not include hollow fiber membranes for blood or plasma perfusion. The device is based on an integral oxygenator and a nonwoven polyester matrix material for hepatocyte culture as small aggregates. The efficacy of this original design was tested in rats with liver ischemia. Preliminary results show statistically significantly improved survival; life was prolonged 100% compared to the control experiments. 相似文献
39.
Reardon O. Olubayo Steve Mihok Eli Munyoki Leonard H. Otieno 《Parasitology research》1994,80(3):177-181
The pattern of infection inGlossina morsitans morsitans andG. m. centralis membrane-fed on eland, buffalo or goat blood mixed withTrypanosoma congolense orT. brucei was studied from day 1 to day 10. Tsetse were initially permissive vectors, with most flies harbouring infections of 104–105 parasites on day 3. However, after a second blood meal on day 3, flies cleared many infections withG. m. morsitans clearing more infections thanG. m. centralis. Infective feeds of goat blood consistently increased final infection rates by limiting the number of infections lost between days 3 and 6. In further experiments withG. m. morsitans only, this effect was replicated by feeding flies on erythrocytes but not on serum. These results suggest that compounds from some mammalian erythrocytes match the target specificity ofG. m. morsitans midgut lectins and, hence, have a protective effect on trypanosome establishment in the fly. 相似文献
40.
Subject case marking and verb morphology in normally developing and specifically language-impaired children 总被引:1,自引:0,他引:1
Recent theories of language development propose a direct relationship between children's use of verb morphology and their use of subject case pronouns. Such proposals might contribute to an understanding of specifically language-impaired (SLI) children's difficulties. These children's extraordinary problems with verb morphology are well documented, and preliminary evidence indicates frequent pronoun case errors (e.g., her for she) in their speech. Thus, it is possible that a collection of difficulties may be linked to a common source in these children. The objectives of this study were to determine: (a) whether subject case marking, as well as verb morphology was more limited in the speech of a group of SLI children than in the speech of a younger group of normally developing (ND) children matched for mean utterance length; (b) whether a relationship between the use of subject case marking and the use of verb morphology existed in the speech of the ND children; and, if so, (c) whether this relationship is evident in the SLI children as well, in spite of their more limited use of these features. The results revealed that the SLI children were more limited than the ND children in the use of both subject case marking and verb morphology. However, a relationship between the two types of usage was found in both groups of children. 相似文献