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71.
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Hyperechogenicity in the breast on ultrasound (US) is usually regarded as a benign feature with only rare hyperechoic malignancies reported to date. In this study, we evaluated the pathologic findings on core needle biopsy of hyperechoic lesions and investigated the histologic features in malignancies that give rise to an echogenic pattern. A total of 163 core needle biopsies (CNB) were performed for “hyperechoic” or “echogenic” lesions between 1/1/05 and 7/31/17. Lesions were classified based on the proportion of hyperechoic areas identified. We found that all lesions with a homogenous hyperechoic pattern (>90% hyperechoic) were benign (n = 17), regardless of the type of margins. Malignancies were found in 21% (7/34, six invasive carcinomas and one lymphoma) of heterogenous lesions with ≥50% hyperechoic areas (all with noncircumscribed margins) and in 31% of lesions with <50% hyperechoic areas (19/61, 14 invasive carcinomas, two lymphomas, and three metastases), including five with circumscribed margins (one invasive carcinoma, one lymphoma, and three metastases). Two major US patterns were identified in malignant lesions, those with a hypoechoic center and hyperechoic rim, corresponding to a central tumor area with dense stroma and tumor cells infiltrating adipose tissue at the periphery (“rim pattern”), and a second “dispersed pattern” with hyperechoic areas distributed throughout the lesion. Hyperechoic malignancies were found to be comprised of a complex intermixture of elements of differing echogenicity including tumor cells, adipose tissue, and fluid (in tubules, stromal clefts, or blood vessels). Our findings support the importance of radiologists specifying the echogenic pattern of hyperechoic lesions, as heterogenous lesions are associated with a higher risk of malignancy and pathologists should be alert to the associated pathologic findings.  相似文献   
73.
The technique of combining stereotactic targeting of breast lesions with an automated spring‐loaded needle biopsy gun reported in 1990 by Steve Parker and colleagues not only ushered in the era of diagnosis almost exclusively by image guided core needle biopsy, but also profoundly changed the practice of pathologists, radiologists, surgeons, and medical oncologists and had major effects on the treatment of women with breast cancer. In this special issue of The Breast Journal celebrating 25 years of publication, it is of value to reflect back on these changes, some expected and some unanticipated, which have occurred over the past three decades and to consider the reasons why core needle biopsies should be considered a milestone in breast pathology.  相似文献   
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75.
目的 探讨超声引导下细针抽吸睾丸组织的诊断价值。 方法 回顾分析2015年1月到2016年12月的睾丸细、粗针穿刺活检病理切片,比较其中生精小管断面数量的差异;除生精小管以外的其他成分(皮肤、血管及纤维软组织)及血肿的差异。 结果 粗针穿刺与细针抽吸睾丸组织病理切片,生精小管断面数量大于20的,粗针穿刺组有8例(8/24,33.3%),细针抽吸组有11例(11/20,55.0%),组间对比(χ2=2.087,P=0.149),两者差异无统计学意义;存在其他成分例数,粗针穿刺组有19例( 19/24,79.2%);细针抽吸组有1例(1/20,0.9%),组间对比(χ2 =24.203,P=0.000),两者差异有统计学意义;穿刺后出现血肿例数,粗针穿刺组有5例(5/24,20.8%),而细针抽吸组20例均未见血肿,组间对比(χ2=4.70,P=0.032),两者差异有统计学意义。 结论 细针抽吸睾丸组织标本满意,几乎无其他成分干扰,具有较大的临床应用价值。  相似文献   
76.
目的研究第1跖骨远端截骨后克氏针和绷带固定对拇外翻的作用效果。方法通过拇外翻的医学影像数据建立完整的三维足部有限元模型,此模型包括足骨、籽骨、软骨、韧带、软组织、跟腱等;分别建立克氏针和绷带固定的模型,分析拇外翻平衡站立时的足部受载特点。结果绷带固定下截骨之间的压应力(14.9 MPa)大于克氏针峰值应力(6.71 MPa)。从背侧、跖侧、内侧、外侧来看,克氏针固定对截骨面的稳定作用都优于绷带固定,更有利于截骨面的稳定。结论绷带固定可减少截骨端的愈合时间,有利于临床上拇外翻术后固定方式的优化选择。  相似文献   
77.
Intraductal proliferations of the breast comprise a heterogeneous group of epithelial proliferations confined to the ductal and lobular system of the breast parenchyma. The correct interpretation and categorization of such lesions can be challenging, especially on core needle biopsy, but are critical for appropriate clinical management as this determines whether surgical excision is or is not required. In this paper we aim to review the histologic criteria and terminology for the spectrum of intraductal proliferative lesions. We will discuss the key morphologic features and diagnostic mimics of usual ductal hyperplasia, atypical ductal hyperplasia, and ductal carcinoma in situ, and provide practical guidelines for interpretation in core needle biopsy specimens.  相似文献   
78.
Alveolar soft part sarcoma is a very rare, slow growing highly angiogenic tumor with poor prognosis. Most common site in children and infants is head and neck region and in adults it most commonly occurs in extremities especially thigh. In our case study, an 8 years old female patient presented with a gradually progressive left shoulder lump. FNAC from the lesion showed cellular smears with polyhedral and spindly cells showing abundant finely vacuolated cytoplasm, nuclear pleomorphism, intranuclear pseudoinclusions, and few bare nuclei. Perivascular arrangement of cells was peculiar in addition to the presence of intracytoplasmic metachromatic PAS positive diastase resistant granules. A presumptive diagnosis of alveolar soft part sarcoma with differentials of granular cell tumor and PEComa was considered and the lesion was excised. Although the histopathological features were not characteristic (ie, showing mainly solid pattern without classic alveolar pattern), immunohistochemistry were diagnostic (negative for S 100, Desmin, Cytokeratin, EMA, and moderate to strong nuclear positivity for TFE3). Thus, the diagnosis of alveolar soft part sarcoma was established. This case is being presented for its rarity and unique cytological and histopathological features.  相似文献   
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80.
Angiosarcomas are rare malignancies arising from cells of endothelial origin and are aggressive sarcomas that can occur in any anatomic site. They are reported to have predilection for the scalp, extremities and breasts. The incidence of these tumors is increasing, which has been suggested to be attributable to the growing use of radiotherapy to treat breast and other malignancies. There is currently limited literature describing the primary cytologic diagnosis of angiosarcoma on fine needle aspirate material. We describe the findings of three cases of angiosarcoma diagnosed by fine needle aspiration. Our three cases offer distinct radiologic, clinical and cytopathologic points‐of‐view: a thyroid angiosarcoma, a mediastinal angiosarcoma and a skin angiosarcoma. The cytomorphology of angiosarcoma is characterized by large highly atypical spindle to epithelioid cells with abundant cytoplasm in dispersed single cells or loose aggregates. The nuclei are large and pleomorphic with vesicular chromatin and prominent nucleoli. Mitoses are readily identified. The background can be bloody and/or necrotic. Occasional intracytoplasmic lumens are a helpful morphologic feature suggesting vascular differentiation. HHV‐8 immunostaining may aid in the differential diagnosis with Kaposi sarcoma while epithelioid hemangioendothelioma can be distinguished based on morphologic features. Given the metastatic potential and high mortality rate associated with these tumors, this entity is an important consideration in the contexts herein described.  相似文献   
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