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41.
目的探讨电视纵隔镜检查术(video-mediastinoscopy,VM)在肺癌术前分期、纵隔肿物诊断和恶性胸腔积液诊治中的价值。方法采用全麻单腔螺纹气管插管,48例行颈部纵隔镜术,33例行胸骨旁纵隔镜检查术,47例行经肋间纵隔镜术。结果125例经电视纵隔镜术后确诊:肺腺癌38例,肺转移性低分化鳞癌33例,结核9例,淋巴结炎症8例,肺小细胞癌7例,胸腺鳞状细胞癌6例,非霍奇金淋巴瘤5例,纵隔神经母细胞瘤4例,胸腺瘤4例,胸膜间皮瘤3例,霍奇金淋巴瘤2例,后纵隔神经鞘瘤2例,结节病1例,胸腺增生1例,类癌1例,中纵隔原始神经外胚叶肿瘤1例。1例电视纵隔镜检查纵隔淋巴结为反应性增生,行左下肺叶切除,病理为鳞癌。2例术前纤维支气管镜病理确诊左下肺鳞癌,电视纵隔镜检查右气管旁淋巴结转移。术中发生气胸1例、出血1例、喉返神经麻痹和切口感染各2例。结论电视纵隔镜术不但是肺癌术前病理分期、纵隔疾病的重要检查方法,而且也是诊治恶性胸腔积液的简便方法。  相似文献   
42.
“C”型曲线的中耳声学特性改变与鼓室积液的关系   总被引:10,自引:2,他引:8  
对40耳声导抗检查为“C”型曲线患耳进行中耳系统共振频率点测试并进行鼓室穿刺抽液,结果表明:共振频率点低于600Hz,患耳鼓室积液阳性率为82.1%,高于600Hz患者鼓室和液阳性率16.7%,提示依据鼓室导抗图和共振频率点测定可初步判断“C”型曲线患耳鼓室积液的可能.  相似文献   
43.
A 4(1/2)-yr-old female presented with right-sided pleural effusion and a retroperitoneal mass. Cytologic analysis of the pleural fluid yielded malignant small round blue cells, which were noncohesive, 3-4 times the size of lymphocytes. The malignant cells had hyperchromatic, pleomorphic nuclei with moderate amounts of vacuolated cytoplasm. A few fiber-shaped cells were also seen. Immunostains for desmin, muscle-specific actin were positive; ultrastructural findings of thick and thin actin-myosin filaments confirmed the diagnosis of embryonal rhabdomyosarcoma. This case illustrates the importance of performing appropriate immunohistochemical stains and ultrastructural studies on cytological material to arrive at a definitive diagnosis.  相似文献   
44.
The pleural space is modeled in two dimensions as a thin layer of fluid separating a deformable membrane and a rigid surface containing a bump. We computed the steady-state membrane configuration and fluid pressure distribution during relative sliding of the two surfaces. For physiologically relevant values of membrane tension, shear flow-induced pressures near the bump and far-field pressure gradients are similar to those measured in vivo within the pleural space (e.g. Lai-Fook et al.) [J. Appl. Physiol.: Respirat. Environ. Exercise Physiol. 56 (1984) 1633-1639]. Deformation of the membrane over the bump suggests that the pressure field generated by the sliding motion promotes an even layer of fluid in the pleural space, preventing asperities from touching. Results also suggest a possible mechanism for pleural fluid redistribution during breathing, whereby irreversible fluid motion is associated with the deformability of the membrane.  相似文献   
45.
探讨铁蛋白ferrztin,Ft在鉴别胸腹液良、恶性质的临界值。用RIA法测定218份由不同病因引起的胸腹液标本铁蛋白(pleuraleffusionferritin,PFt)及其同期血清铁蛋白(SFt)。依据临床确诊资料,将标本进行良、恶性病例分组,比较两组PFt、SFt,计算PFt/SFt比值,用ROC曲线选择PFt用于良、恶性质鉴别的最佳临界值。结果表明,良性组PFt为142.4±38.6μg/L,SFt为89.7±43.5μg/L,PFt/SFt为1.46±0.55;恶性组PFt为576.5±239.1μg/L,SFt为189.6±81.7μg/L,PFt/SFt为3.67±1.48;PFt用于鉴别胸腹液良、恶性质的临界值为400μg/L。以恶性积液PFt≥400μg/L、PFt/SFt≥3,良性积液PFt<400μg/L、PFt/SFt<3为实验诊断标准鉴别胸腹腔积液的良、恶性质,灵敏度为84.5%、特异性为87.5%,准确性为92.8%。  相似文献   
46.
We characterized on immuno- and enzymecytochemical level the lymphoid and non-lymphoid cells in the adenoid of children with upper respiratory tract infections (URI) and otitis media with effusion (OME) and compared these with the adenoid of children with URI without OME and with the adenoid of 'healthy' children and adults. Besides macrophages and dendritic cells we also showed the presence of MHC class II positive, ciliated, epithelial cells. These non-lymphoid cells were present in all adenoids. However, their number was less than 1% of all cells. We found no difference in lymphocyte subsets from children with URI + OME compared with those from children with URI alone. These two groups showed a significant decrease of CD8-positive (suppressor/cytotoxic) cells and a slight increase in CD22-positive B cells in comparison to 'healthy' children. No difference was found in percentages of CD4-positive (helper/inducer) cells. The localization of the lymphoid subsets in adenoids of children with URI and/or OME did not differ from those of 'healthy' children and adults.  相似文献   
47.
Summary The cytological diagnosis of malignant Lymphoma in serous effusions can be difficult because reactive lymphocytes may be morphologically indistinguishable from malignant cells in lymphocytic and other low grade Non-Hodgkin's lymphomas. As a result of the present study, diagnostic accuracy can be improved by means of B- and T-cell enumeration using an immunoalkaline-phosphatase method (IAP). 30 cytological specimens, including 28 pleural, 1 pericardial and 1 ascitic fluids, were studied with a panel of monoclonal anti B- and anti T-cell antibodies (PAN B, kappa, lambda, T1, T2, OKT4, T8). Reactive lymphocytic effusions were characterized by a predominance of T cells constituting 80% of all lymphocytes with an excess of helper/inducer cells (mean helper to suppressor ratio 3.0) and by a surface kappa to surface lambda ratio of 1.6 on B-cells. Tuberculous effusions showed a similar distribution of lymphocyte-subpopulations whilst most of the carcinomatous fluids showed a lower percentage of T cells (lowest value 67%) and lower Th:Ts ratio (mean 2.0). Lymphoid cells in samples of five B-cell lymphomas were characterized by T-cell depression ( 70%). B-cells in three cases expressed clear cut light chain monoclonality which was at least suggested in the other two cases.Lymphoid cells from two cases of Hodgkin's disease expressed an indistinct immunological pattern. Labelling of cytoplasmic immunoglobulins (heavy and light chains) using the peroxidase antiperoxidase method (PAP) may be important to characterize neoplasms of the plasma cell series.It is concluded that the chosen panel of antibodies in combination with IAP labelling method may be of great value in identifying B-cell lymphomas. The technique can be used in the routine laboratory and storage of unlabelled and labelled slides over long periods is possible.Dedicated to Professor K. Lennert, Kiel, on the occasion of his 65th birthdayThis study was supported by the Krebsliga St. Gallen/Appenzell  相似文献   
48.
Discrepant results in effusion immunocytochemistry are often the result of specimen processing. Smears, cytospins, cell blocks, and monolayer preparations have all been used in various published studies; thus, there is no consistency in the immunostaining process for cytology to compare with the surgical pathology "gold standard" results. We sought to evaluate optimal specimen preparation for the immunostaining of effusion samples. Fourteen reactive and 15 malignant effusion samples (various epithelial/mesothelial neoplasms) were each prepared in three forms: air-dried cytospins (postfixed in ethanol), formalin-fixed, paraffin-embedded cell blocks, and liquid-based thin-layer (ThinPrep, CYTYC, Boxborough, MA) processing. All slides were immunostained with antibodies commonly used in effusion cytology: HBME-1, calretinin, E-cadherin, BerEP4, B72.3, LeuM1, and CA19-9. Cytospin and ThinPrep samples performed in a similar manner: high background staining was encountered in 66% of cases, most evident in three-dimensional clusters of cells. In addition, membrane staining patterns were difficult to interpret. Cell blocks provided the best milieu for morphologic interpretation, with less background staining (only 17% of cases) and results that most closely approximated those reported in the surgical pathology literature. The cost per test for cell block immunocytochemistry was also the most economical for our laboratory.  相似文献   
49.
The human malignant pleural mesothelioma is related to the use of asbestos in the majority of cases. Though the use of asbestos has been prohibited since the 1990s, the incidence of pleural mesothelioma is still increasing because of a latency period of at least 20 years. This study investigated the benefit of single therapy with cyclophosphamide or hyperthermia or the combination of both on cells of a human pleural mesothelioma cell line, xenotransplanted subcutaneously in the paw of mice. A CONTROL group received the same volume of physiological saline. The oxygenation of tumours was measured, tumour growth was followed over 3 weeks, immunohistochemical studies and a light and electron microscopic evaluation were performed. Chemotherapy or hyperthermia alone was only temporarily effective. The greatest benefit was achieved using combined thermochemotherapy consisting of cyclophosphamide plus hyperthermia: 50% of this group had partial remissions, and 67% responded to this therapy. After 3 weeks tumours grew again. Superior effects could be achieved by performing additional cycles of chemotherapy or adding another drug or radiation for instance. This study shows promising results in the treatment of malignant pleural mesothelioma.  相似文献   
50.
Pitfalls in TRAP assay in routine detection of malignancy in effusions   总被引:5,自引:0,他引:5  
Telomerase has been found to be reactivated in a majority of cancers but is inactive in most somatic cells. Our principal goal was to determine the potential use of the telomeric repeat amplification protocol (TRAP) assay as marker for malignancy in cytological effusions. The simple selection criterion was the cytological diagnosis, and routine samples were classified into malignant (58 samples) and nonmalignant (233 samples). Of the malignant samples, 44/58 (76%) were positive by TRAP assay. Of the 14 telomerase-negative cytology-positive samples, RNA integrity was poor in 9, indicating suboptimal sample conservation for molecular analysis. In 3 of the remaining 5 samples with a negative TRAP assay, a high number of malignant cells was observed, and these cells might have been telomerase-negative. Thus, the sensitivity of TRAP assay for the presence of malignant cells was about 76%. In the cytologically nonmalignant effusions, the presence of telomerase activity was observed in 24% (55/233). Of these, 6% were highly suspicious for malignancy, 9% were doubtful, and 9% were cytologically nonmalignant effusions confirmed by a follow-up of 12 mo or more. According to these data, the specificity of the TRAP assay to detect tumor cells in effusions ranged only between 82-91%. Our results indicate that, although the TRAP assay is positive in 6-15% of putative malignant effusions, the relatively high number of TRAP false-negative and false-positive cases renders this test unsuitable for routine diagnostic purposes.  相似文献   
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