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81.
Fine-needle aspiration cytology (FNAC) plays a key role in the preoperative diagnosis of breast carcinoma but is less reliable in the diagnosis of in situ lesions. The objective of the present study was to investigate the cytological features of lobular carcinoma in situ (LCIS), regarding which little data is available to date. Cytological features of FNAC of the breast from 21 patients with histology-proven LCIS were described and compared with surgical specimens. Aspirates from 8/21 cases had cell groups diagnostic for or compatible with LCIS. Aspirates from an additional two cases demonstrated hypercellular, dissociated, and more pleomorphic tumor cells, which were originally diagnosed as invasive lobular carcinoma (ILC). The remaining 11 aspirates were diagnosed as benign or nondiagnostic. FNAC from the eight diagnostic specimens were characterized by loosely cohesive cell groups composed of uniform cells with occasional intracytoplasmic lumina, slightly irregular and eccentric nuclei. We conclude that the main difficulty in diagnosing LCIS by FNAC is sampling rather than recognition of the lesions. However, one should be aware of the cytological features of LCIS in order to reach a correct diagnosis. There are no reliable cytological criteria that help in differentiating pleomorphic and dissociated LCIS from ILC. 相似文献
82.
Fine-needle aspiration (FNA) is a reliable, safe, and cost-effective procedure with a well-established role in the diagnosis of various solid tissue neoplasms. The role of FNA in the diagnosis of primary bone tumors, including osteosarcoma (OGS), is controversial and has yet to be established. We reviewed our experience with the use of FNA as a diagnostic technique over the past 8 yr at our institution. Diagnosis was conclusive in 26 (65%) of 40 patients, 18 of whom went to neoadjuvant therapy and/or resection based solely on the FNA interpretation of either "high grade sarcoma" or "osteosarcoma." Of the remaining 14 (25%) patients, 12 had inconclusive diagnosis and two (5%) were false-negatives. An inconclusive diagnosis was most likely to be an inadequate or paucicellular aspirate, seen in six (15%) patients. An additional six patients had variants of osteosarcoma (four chondroid, one "giant cell rich," one parosteal) that made definitive diagnosis impossible. The two that were incorrectly classified were diagnosed as fracture callus and plasmacytoma. FNA is an accurate and cost-effective tool for the initial diagnosis of primary osteosarcoma with a sensitivity of 65% and accuracy of 95%. Inconclusive diagnoses are likely to be due to insufficient sample cellularity or the presence of OGS variant. In our experience, FNA is sufficient to provide the diagnosis of OGS prior to definitive treatment when interpreted in conjunction with imaging studies and clinical findings. In those cases where FNA fails to yield a diagnostic sample, a traditional biopsy can be performed. 相似文献
83.
This article reports the cytodiagnosis of three cases of retinoblastoma in children aged 1.5, 2.5, and 5 yr. Two of them were diagnosed by fine-needle aspiration cytology of the primary tumor and one by aqueous cytology. The tumor cells were usually round to oval, small and uniform, with scanty cytoplasm; they generally occurred in closely packed clusters of variable sizes. We discuss the differential diagnosis of retinoblastoma with other round-cell tumors of childhood involving the orbit. 相似文献
84.
Seven cases of spindle-cell proliferations in which fine-needle aspiration biopsy (FNAB) did not correlate with subsequent histology are presented. Three cases were considered low-grade sarcoma, one a dermatofibrosarcoma protuberans (DFSP), one a spindle-cell tumor with malignancy not excluded, and one a rhab-domyosarcoma vs. a fibrosarcoma. Two of the these three were histologically nodular fasciitis and one an inflammatory pseudotumor. Two cases were diagnosed cytologically as fibromatosis or nodular fasciitis (NF). One of these histologically was an intramuscular hemangioma, the other a DESP. The last two cases were diagnosed by FNAB as spindle-cell lesion, undetermined if benign or malignant, and malignant fibrous histiocytoma (MFH). Histologically both of these case were leiomyosarcoma. The cyto-logic features of each case, differential diagnosis, and potential pitfalls are discussed. In the evaluation of FNAB smears dominated by spindle cells, cellullarity, individual cells and cell patterns,and background stromal features coupled with a precise clinical history may allow a narrow differential diagnosis with a focus on whether the lesion is benign or malignant. Caution is warranted in the exact classification of spindle-cell tumors from FNAB as this may have a major impact on patient management. © 1994 Wiley-Liss, Inc. 相似文献
85.
Walid A. Mourad Nour Sneige Ruth L. Katz Nancy P. Caraway Tina V. Fanning 《Diagnostic cytopathology》1994,11(4):328-332
We report the cytological and clinical findings of 16 fine-needle aspirates (FNAs) performed on recurrent (n = 6) and metastatic (n = 10) mixed mesodermal tumors (MMMTs). The median interval between the primary diagnosis and FNA was 16 mo. Primary sites were the endometrium (n = 11), the ovary (n = 3), the cervix (n = 1), and pelvic soft tissue (n = 1). Primary tumors showed carcinoma with homologous mesenchymal components in 13 cases and focal heterologous elements in three (two chondrosarcomas and one rhabdomyosarcoma). The FNAs showed carcinoma in all 16 cases, with adenocarcinoma differentiation in three, Mesenchymal elements were identified in aspirates of three recurrent and two metastatic lesions. They were all homologous. No heterologous mesenchymal elements were identified in the aspirates. We conclude that mesenchymal components in FNAs of MMMTs are less likely to be seen in metastatic lesions, and that heterologous mesenchymal components are rarely seen in these aspirates even in recurrent disease. These findings confirm that the epithelial component is responsible for the malignant behavior of MMMTs, and suggest that these lesions may need to be classified as sarcomatoid carcinomas rather than true carcinosarcomas. Diagn Cytopathol 1994;11:328–332. © 1994 Wiley-Liss, Inc. 相似文献
86.
In its pure form, mucinous breast carcinoma (MC) has a much better prognosis than infiltrating ductal carcinoma (IDC). Mixed MC-IDC has the prognosis of IDC. We compared the fine-needle aspiration (FNA) cytology and histology of nine cases of pure MC with 13 cases of mixed MC-IDC. While typical of pure MC, abundant mucin (3+/3+) was noted in smears from three cases of mixed tumor and is thus necessary but not sufficient for a diagnosis of pure MC. Cellular pleomorphism has been said not to be a feature of MC; however, we found occasional large cells markedly different from the typical small uniform cells of MC in four pure and seven mixed tumors. Cytologic features indicative of a mixed tumor include one or more smears totally without mucin, scantly amounts of mucin, or necrosis. A combination of features indicative of pure mucinous carcinoma in FNA included abundant mucin on all smears, no pleomorphism, and no necrosis. Many cases will have smear patterns that are not typical of either profile and should probably be designated as carcinoma with a mucinous component. 相似文献
87.
Adamantinoma of long bones is a rare, primary bone tumor of controversial histogenesis, usually arising in the anterior midshaft of the tibia. This slowly growing, radiolucent, expansile tumor eventually causes thinning or destruction of overlying cortical bone. Fine-needle aspiration biopsy (FNAB) is a rapid, safe, and relatively painless means of obtaining diagnostic material from bone tumors, provided the mass has eroded through or markedly attenuated the overlying cortex. A case is presented of primary adamantinoma of the tibia which was sampled first by FNAB and subsequently by surgical biopsy. 相似文献
88.
Eighty-six fine-needle aspirates (FNAs) of pancreas from 74 patients were reviewed. Histological confirmation or clinical follow-up of the final diagnosis was available in 61 aspirates from 49 patients. Of 42 proven malignant cases, FNAs were diagnosed as positive in 21 (50%), suspicious in 4 (9.5%), negative in 12 (28.6%), and unsatisfactory in 5 (11.9%). Of 19 proven benign cases, FNAs were diagnosed as negative in 15 (78.9%) and unsatisfactory in 4 (21%). This resulted in a 50% sensitivity, a 100% specificity, a diagnostic efficiency of 59%, a predictive value of a positive test of 100%, and a predictive value of a negative test of 55.6%. Thirty-six primary pancreatic adenocarcinomas and six metastatic tumors to the pancreas were encountered. Benign cases were attributed to anatomical pancreatic variants, acute pancreatitis, abscess, chronic pancreatitis, and pseudocysts. Pancreatic FNA was safe, accurate, and relatively inexpensive, but it was relatively insensitive in the diagnosis of malignancy. 相似文献
89.
The cytological evaluation of ovarian cystic fluid using ThinPrep has not been reported. To determine the diagnostic accuracy of ThinPrep cytology in distinguishing between benign and nonbenign ovarian cystic lesions, we examined 65 fluid samples aspirated during intraoperative consultation with subsequent histologic correlation. One ThinPrep slide was prepared from each sample aspirated from surgically removed ovarian cystic masses and reviewed blindly by a panel of three cytopathologists. The parameters used in cytological evaluation were cellularity, cell types, cellular arrangement, and background. Four samples were acellular and excluded from the study. The consensus cytologic diagnoses were compiled for 61 cases which were assigned to one of the following diagnostic categories: negative for malignant cells (40 cases), atypical cytology (13 cases), and suspicious or positive for malignancy (8 cases). Histologic correlation of the cytological benign/negative cases showed that 26/40 (65%) were histologically benign and 14/40 were false-negative (35%, 5 carcinomas and 9 borderline tumors) with 10 of these cases being mucinous tumors. Most false-negative cytologic samples (11/14 or 79%) did not have an epithelial component. Of the 21 cytological nonbenign diagnoses (atypical/suspicious/positive), 15 (71%) were confirmed on histology (10 carcinomas and 5 borderline tumors). However, a nonbenign cytologic diagnosis was rendered in 6 histologically benign cases, including 2 serous cystadenomas, 1 mucinous cystadenoma, 1 serous cystadenofibroma, 1 endometriosis, and 1 corpus luteal cyst. The diagnostic sensitivity by ThinPrep evaluation of ovarian cystic masses is 81% (26/32) for benign and 52% (15/29) for nonbenign lesions. Our results concluded that ThinPrep examination of ovarian cystic fluid is not accurate in distinguishing benign from malignant cysts, given the significant number of false-negative diagnoses. Major contributing factors include sparse cellularity of the fluid samples and mucinous differentiation of the tumors. 相似文献
90.
We report on the cytopathologic findings of a Leydig-cell tumor of the testis in a young adult male with no evidence of endocrine dysfunction. The preoperative diagnosis was based on fine-needle aspiration cytology (FNAC) alone, which was subsequently confirmed on histopathology. The present case was of interest on account of the paucity of literature regarding the cytodiagnosis of this lesion. In addition, the finding of intracytoplasmic lipofuscin pigment and several intracytoplasmic as well as intranuclear Reinke's crystals served to clinch the diagnosis on FNA. Therefore, the use of FNAC, especially in the presence of diagnostic Reinke's crystals, may vitiate the need for more invasive biopsy procedures in the preoperative diagnosis of testicular Leydig-cell tumors. 相似文献