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1.
目的采用图像融合技术获得T2WI与T2WI-FS的融合图像,评估其在肛瘘及肛周结构显示中的优势。
方法2016年6月至2018年6月,前瞻性选择中山大学附属第一医院29例肛瘘患者进行肛管磁共振(MR)检查,采用图像融合技术获取T2WI与T2WI-FS的融合图像T2WI-Fusion,利用Fisher score算法计算瘘管及肛门括约肌的组织间分辨力Fisher值、脂肪与肛门括约肌间的Fisher值,评估融合图像中瘘管及肛周结构的显示情况。采用改进的双刺激连续质量量表(DSCQS)对T2WI-FS、T2WI、增强3D-VIBE和T2WI-Fusion序列图像进行主观图像质量评价。
结果29例患者均成功获得T2WI与T2WI-FS的融合图像T2WI-Fusion。T2WI-Fusion、T2WI瘘管与括约肌间Fisher均值分别为6.46、3.31,T2WI-Fusion图像对瘘管的显示优于T2WI序列图像(P<0.001)。T2WI-Fusion、T2WI-FS脂肪与括约肌间Fisher均值分别为10.61、2.45,T2WI-Fusion图像对括约肌的显示优于T2WI-FS序列图像(P<0.001)。T2WI-Fusion对瘘管与括约肌的图像质量评价总评分均高于T2WI-FS、T2WI、增强3D-VIBE序列(P<0.001)。
结论MRI图像融合技术同时具备T2WI及T2WI-FS的优势,无需增加扫描序列及扫描时间,且操作简单,花费时间短,显著提高病变及肛周解剖结构的对比度和图像质量。 相似文献
2.
目的 探讨磁共振成像各种方法对脑静脉畸形的诊断价值。方法 收集本院6例脑静脉畸形病例,均进行过磁共振T1WI、T2WI扫描,其中部分病例做过DWI、T2FLAIR、MRA、MRV、T1WI增强扫描及DSA。结果 幕上4例,幕下2例,T1WI、T2WI表现:引流静脉均为流空的低信号,深髓静脉为细条状长T1、长T2信号。其中1例DWI引流静脉及深髓静脉区域低信号;1例T2 FLAIR引流静脉流空的低信号,深髓静脉高信号;2例MRA均阴性,但MRV显示深髓静脉汇入引流静脉;2例T1 WI增强扫描:深髓静脉呈轮辐状汇入引流静脉;1例DSA:动脉期阴性,静脉期见典型的“海蛇头”征。结论 磁共振能明确诊断脑静脉畸形,T1WI增强扫描及MRV均较敏感,DSA为诊断脑静脉畸形金标准。 相似文献
3.
P.M. Freedman Barbara Ault C.R. Zeiss M.W. Treuhaft R.C. Roberts D.A. Emanuel M.C. Baldauf J.J. Marx 《The Journal of allergy and clinical immunology》1981,67(1):51-58
Intradermal skin tests with a culture filtrate antigen of Micropolyspora faeni grown on a synthetic medium were performed on patients with farmers' lung disease (FLD) and well farmers with and without antibodies to a panel of FLD antigens. Seventy-five percent of the FLD patients, 79% of the well farmers with M. faeni antibody, and 5% of well farmers without M. faeni antibody had a 2+ or greater intradermal immediate skin-test reaction. Prausnitz-Küstner (P-K) reactions were positive using serum of M. faeni immediate skin test-positive FLD patients. IgG-rich fractions from a staphylococcal protein A-Sepharose column of such serum contained the sensitizing factor whereas IgG-depleted fractions did not. M. faeni—specific IgE could not be detected in serum by a polystyrene radioimmunoassay. Positive late-onset (6-hr) skin tests occurred only in FLD patients and farmers with precipitating antibody. Biopsy specimens of the 6-hr reactions revealed a generalized dermal and perivascular polymorphonuclear infiltrate with deposits of immunoglobulin and complement about blood vessels. The skin-sensitizing factor noted in FLD patients and well farmers with antibody is not disease specific. This factor appears to be associated with the IgG-rich fraction of serum, and its role in the pathogenesis of FLD is unclear. 相似文献
4.
5.
D M Jacobson 《Ophthalmology》1999,106(10):1994-2004
OBJECTIVE: To characterize the clinical features and course of patients with magnetic resonance imaging (MRI)-defined optic nerve compression by the supraclinoid carotid artery. DESIGN: Retrospective, observational case series. PARTICIPANTS: Eighteen patients with 24 affected eyes were identified by reviewing case records from the author's referral-based neuro-ophthalmology practice. Predetermined inclusion and exclusion criteria were applied to potential participants. MAIN OUTCOME MEASURES: The following variables were abstracted from the medical record: age, gender, presenting symptoms, past medical problems, visual acuity, color vision, visual field, pupillary reactions, optic disc appearance, other neurologic signs, and previously documented and follow-up examinations. RESULTS: There were eight women and ten men ranging in age from 28 to 86 years (median age, 72 years) at the time of diagnosis. Ten (56%) of 18 patients had hypertension. Twelve patients had unilateral optic neuropathy, whereas 6 patients had bilateral optic neuropathy. One patient presented with subacute superior orbital fissure syndrome due to mass effect of a dolichoectatic carotid artery. Another patient had oculomotor nerve palsy with signs of aberrant regeneration due to intracavernous mass effect of a dolichoectatic carotid artery. One patient had a bitemporal hemianopia associated with bilateral compression of the immediate prechiasmatic optic nerves by dolichoectatic carotid arteries. The predominant pattern of visual field loss in most patients reflected nerve fiber bundle injury. A central scotoma or absolute central visual field loss was noted in only 6 (25%) of 24 affected eyes. Most patients demonstrated saucerlike excavation of the optic disc. Progression of visual acuity loss occurred at a relatively slow rate. CONCLUSIONS: Although uncommon, intracranial compression of the optic nerve by the carotid artery should be considered in a patient with unexplained or progressive unilateral or bilateral optic neuropathy. This entity can be diagnosed using clinical skills to exclude more common causes of optic nerve injury and coronal-oriented MRI to confirm anatomic compression of the symptomatic optic nerve. Although many affected patients have excavation of the optic disc and nerve fiber bundle visual field defects, most have additional signs atypical for glaucoma, minimizing the potential for diagnostic confusion between the two disorders. 相似文献
6.
Alpha1-acid glycoprotein (alpha1-AG) was purified from human sera, and its binding properties with respect to psychotropic drugs were examined by equilibrium dialysis methods in order to clarify the specificity of binding. Radioactive imipramine, a tricyclic antidepressant, was used as the primary ligand. Other drugs, representative of different classes, were tested as potential inhibitors of the alpha1-AG-imipramine binding. The K(a) for imipramine was 2.8 x 10(5) (+/- 0.8) M(-10 (mean +/- S.D.). Chlorpromazine, fluphenazine, thioridazine, loxapine and thiothixene, which are antipsychotic drugs, were competitive inhibitors of imipramine binding, and their K(a) values were in the same range. Propranolol, haloperidol and diazepam were also competitive inhibitors but their affinities were lower. Molindone, an indolic antipsychotic, when tested at the same concentrations as the other drugs, did not affect imipramine binding. Trihexyphenidyl, an anti-Parkinson drug, was a potent but noncompetitive inhibitor. These data identify the antidepressant and major tranquilizer drugs that exhibit high affinity for alpha1-AG and indicate that alpha1-AG may account for 40 per cent of total imipramine bound in serum. Since in psychiatric clinical practice two drugs are frequently administered together, possible competitive effects are discussed as well as the potential role of alpha1-AG in psychiatric illness. 相似文献
7.
Serologic studies in a family with heterozygous C2 deficiency 总被引:1,自引:0,他引:1
D J McCarty E M Tan N J Zvaifler S Koethe R J Duquesnoy 《The American journal of medicine》1981,71(6):945-948
Twelve family members of a patient with systemic lupus erythematosus (SLE) and heterozygous deficiency of the second component of complement (C2) were studied. Histocompatibility (HLA) typing was determined for A, B, and DR and MB antigens. Serum samples were tested for a variety of antinuclear antibodies (ANA), lymphocytotoxic antibodies and rheumatoid factors, and C2 levels were determined by hemolytic titration. Inheritance of C2D, the gene coding for C2, was limited to the haplotype HLA-A25, B18, DR2. Low but significant titers of ANA, rheumatoid arthritis nuclear antigen (RANA) and/or rheumatoid factors were found in eight of the nine adult family members without association with HLA haplotype. The sister of the proband had persistently strongly positive LE cell preparations for more than a decade and had joint pains while taking sulfa drugs. The son of the proband had leukemia. All other family members were healthy. We conclude that the increased incidence of rheumatic disease in persons with C2D deficiency is multifactorial and requires environmental factors or other hereditary factors unrelated to the HLA-A25, B18, DR2 haplotype. The C2D gene is clearly not associated with positive ANA tests or immunoprecipitins to RANA. 相似文献
8.
9.
Sheryl L. Coley Jasmine Y. Zapata Rebecca J. Schwei Glen Ellen Mihalovic Maya N. Matabele Elizabeth A. Jacobs Cynthie K. Anderson 《Women's health issues》2018,28(2):158-164
Introduction
African American mothers and other mothers of historically underserved populations consistently have higher rates of adverse birth outcomes than White mothers. Increasing prenatal care use among these mothers may reduce these disparities. Most prenatal care research focuses on prenatal care adequacy rather than concepts of quality. Even less research examines the dual perspectives of African American mothers and prenatal care providers. In this qualitative study, we compared perceptions of prenatal care quality between African American and mixed race mothers and prenatal care providers.Methods
Prenatal care providers (n = 20) and mothers who recently gave birth (n = 19) completed semistructured interviews. Using a thematic analysis approach and Donabedian's conceptual model of health care quality, interviews were analyzed to identify key themes and summarize differences in perspectives between providers and mothers.Findings
Mothers and providers valued the tailoring of care based on individual needs and functional patient–provider relationships as key elements of prenatal care quality. Providers acknowledged the need for knowing the social context of patients, but mothers and providers differed in perspectives of “culturally sensitive” prenatal care. Although most mothers had positive prenatal care experiences, mothers also recalled multiple complications with providers' negative assumptions and disregard for mothers’ options in care.Conclusions
Exploring strategies to strengthen patient–provider interactions and communication during prenatal care visits remains critical to address for facilitating continuity of care for mothers of color. These findings warrant further investigation of dual patient and provider perspectives of culturally sensitive prenatal care to address the service needs of African American and mixed race mothers. 相似文献10.