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21.
Cardoso AA; Schultze JL; Boussiotis VA; Freeman GJ; Seamon MJ; Laszlo S; Billet A; Sallan SE; Gribben JG; Nadler LM 《Blood》1996,88(1):41-48
Even if neoplastic cells express tumor associated antigens they still may fail to function as antigen presenting cells (APC) if they lack expression of one or more molecules critical for the induction of productive immunity. These cellular defects can be repaired by physiologic activation, transfection, or fusion of tumor cells with professional APC. Although such defects can be repaired, antitumor specific T cells may still fail to respond in vivo if they may have been tolerized. Here, human pre-B cell acute lymphoblastic leukemia (pre-B ALL) was used as a model to determine if primary human tumor cells can function as alloantigen presenting cells (alloAPC) or alternatively whether they induce anergy. In the present report, we show that pre-B cell ALL express alloantigen and adhesion molecules but uniformly lack B7-1 (CD80) and only a subset express B7-2 (CD86). Pre-B ALL cells are inefficient or ineffective alloAPC and those cases that lack expression of B7-1 and B7-2 also induce alloantigen specific T- cell unresponsiveness. Under these circumstances, T-cell unresponsiveness could be prevented by physiologic activation of tumor cells via CD40, cross-linking CD28, or signaling through the common gamma chain of the interleukin-2 receptor on T cells. Taken together, these results suggest that pre-B ALL may be incapable of inducing clinically significant T-cell-mediated antileukemia responses. This defect may be not only due to their inability to function as APC, but also due to their potential to induce tolerance. Attempts to induce clinically significant antitumor immune responses may then require not only mechanisms to repair the antigen presenting capacity of the tumor cells, but also reversal of tolerance. 相似文献
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Airborne allergic contact dermatitis caused by isothiazolinones in water‐based paints: a retrospective study of 44 cases 下载免费PDF全文
Emmanuelle Amsler Olivier Aerts Nadia Raison‐Peyron Michèle Debons Brigitte Milpied Fran?oise Giordano‐Labadie Julie Waton Marie C. Ferrier‐Le Bou?dec Isabelle Lartigau Catherine Pecquet Haudrey Assier Martine Avenel‐Audran Claire Bernier Florence Castelain Evelyne Collet Marie‐No?lle Crépy Nathalie Genillier Pascal Girardin Pauline Pralong Florence Tetart Dominique Vital‐Durand Angele Soria Annick Barbaud 《Contact dermatitis》2017,77(3):163-170
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目的:探讨如达溃疡散对大鼠乙酸性胃溃疡的作用及对其血清促胃液素(gastrin)含量的影响.方法:采用乙酸法复制胃溃疡模型,将大鼠随机分为对照组、如达溃疡散组、雷尼替丁组,观察如达溃疡散对大鼠胃溃疡的作用,并检测其对大鼠血清中促胃液素含量的影响.结果:与对照组相比,如达溃疡散能明显抑制溃疡的发生,抑制血清促胃液素含量.结论:如达溃疡散具有抗胃溃疡的作用,其作用机理可能是通过抑制促胃液素释放,进一步减少胃酸分泌来实现的. 相似文献
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Background: Adolescent females are the most frequent victims of sexual assault, but studies to document the presence of genital findings in patients examined within 72 hours, using magnification and dye, have not been published. This study was designed to document the frequency and types of genital injuries in adolescent women following acute sexual assault, using chart and photograph review.Methods: A retrospective chart review was done of examination records of all female patients age 14 to 19 years of age who were evaluated at a Sexual Assault Response Team program over a 5 year period. Data was abstracted from charts by the nurse examiners, and photographs were evaluated by the physician reviewer. Analysis was done to determine the frequency, location, and severity of genital and anal injuries, and any historical factors correlating with injury, using Pearson correlation and two-tailed t tests.Results: Charts of 214 female subjects (mean age 16.3 years) were reviewed. The most common findings recorded by the nurse examiner were posterior fourchette tear (36%), erythema of the labia minora, hymen, cervix or posterior fourchette (18% to 32%), and swelling of the hymen (19%). Uptake of Toluidine dye was noted in 66% of patients in whom it was applied. Overall, 21% of patients were found to have no findings, and 40% had tears of the posterior fourchette or fossa. Time to examination was highly correlated with the degree of injury noted (p =.000). The incidence of hymenal tears in self-described virgins was higher than in non-virgins (19% vs. 3%, p =.008), however the total number or severity of other injuries was not significantly higher in virgins. Reported anal penetration was associated with a high frequency of anal bruising, abrasions or tears (14/23, 61%), while only 2/150 victims who denied anal penetration had tears (1%, p =.000). Victims who reported multiple physical symptoms such as pain, nausea, or vomiting were significantly more likely to be older (p =.034) and to have an increased number of non-genital injuries such as bruising, abrasions, and bite marks (p =.001). A higher number of non-genital injuries was also correlated with a higher number of total genital injuries (p =.003).Conclusions: Adolescent victims of sexual assault who were examined within 72 hours, using a magnification and dye were found to have tears of the posterior fourchette or fossa in 40% of cases. Hymenal tears were rare, even in self-described virginal girls. Timely examination of adolescent victims is important to document injuries, however, many victims will still have non-specific examination findings. 相似文献
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To standardize industrial implant production and make comparisons between different experimental results, we have to be able to quantify the crystallinity of hydroxyapatite. Methods of measuring crystallinity ratio were developed for various HA samples before and after plasma spraying. The first series of methods uses X-ray diffraction. The advantage of these methods is that X-ray diffraction equipment is used widely in science and industry. In the second series, a neutron diffraction method is developed and the results recorded are similar to those obtained by the modified X-ray diffraction methods. The advantage of neutron diffraction is the ability to obtain measurements deep inside a component. It is a nondestructive method, owing to the very low absorption of neutrons in most materials. 相似文献
29.
Use of calcium excretion values to distinguish two forms of primary renal tubular hypokalemic alkalosis: Bartter and Gitelman syndromes. 总被引:18,自引:0,他引:18
A Bettinelli M G Bianchetti E Girardin A Caringella M Cecconi A C Appiani L Pavanello R Gastaldi C Isimbaldi G Lama 《The Journal of pediatrics》1992,120(1):38-43
Clinical or biochemical findings were reevaluated in 34 pediatric patients with primary renal tubular hypokalemic metabolic alkalosis. The patients were subdivided into two groups. Bartter syndrome (primary renal tubular hypokalemic metabolic alkalosis with normocalciuria or hypercalciuria) was diagnosed in 18 patients with molar urinary calcium/creatinine ratios greater than 0.20, and Gitelman syndrome (primary renal tubular hypokalemic metabolic alkalosis with magnesium deficiency and hypocalciuria) was diagnosed in 16 patients with molar urinary calcium/creatinine ratios less than or equal to 0.20 and plasma magnesium levels less than 0.75 mmol/L. Some clinically important differences between the groups were observed. Patients with Bartter syndrome were often born after pregnancies complicated by polyhydramnios (8/18) or premature delivery (7/18) and had short stature (11/18) or polyuria, polydipsia, and a tendency to dehydration (16/18) during infancy (12/18) or before school age (18/18). Patients with Gitelman syndrome had tetanic episodes (12/16) or short stature (3/16) at school age (14/16). We conclude that the Bartter and Gitelman syndromes represent two distinct variants of primary renal tubular hypokalemic metabolic alkalosis and are easily distinguished on the basis of urinary calcium levels. 相似文献
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