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51.
An inhibitory mechanism toward gastrin hypersecretion is significantly different between G‐cell hyperplasia and gastrinoma despite the common clinical manifestations; hypergastrinemia and its related persistent gastric ulcers. We recenlty studied the G‐cell, d ‐cell and ECL‐cell density in a case of G‐cell hyperplasia. The 70‐year‐old patient has been treated for persistent gastric ulcers with a markedly increased plasma gastrin (5600 pg/mL). The stomach was surgically resected because of the obstruction associated with ulcer scars. The number of G‐cells in the pyloric glands was quantified on the surgical specimens and G‐cell hyperplasia was histolopathologically identified. Immunostainig of histidine decarboxylate revealed the presence of ECL‐cell hyperplasia in the pyloric glands and its density was significantly and positively correlated with G‐cell density. Somatostatin immunoreactive cells (d ‐cells) increased in their number in the oxyntic glands. These results all indicated that hypersecretion of gastrin in G‐cell hyperplasia could induce ECL‐cell proliferation in a paracrinal manner. In addition, relatively non‐prominent endocrinological features in the G‐cell hyperplasia compared to gastrinoma could be also related to the paracrinal somatostatin inhibitory effects upon ECL‐cells in the pyloric glands.  相似文献   
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Both intravascular ultrasound (IVUS) and optical coherence tomography (OCT) play a crucial role in elucidating the pathophysiology of coronary artery disease (CAD) with the goal to improve patient outcomes of medical and/or interventional CAD management. However, no single intravascular imaging technique has been proven to provide complete and detailed evaluation of all CAD lesions due to some limitations. Although sequential use of multiple modalities may sometimes be performed, there may be issues related to risk, time, and cost. To overcome these problems, several hybrids involving dual-probe combined IVUS-OCT catheters have been developed.The aim of this review article is to demonstrate some limitations of stand-alone imaging devices for evaluation of CAD, summarize the advances in hybrid IVUS-OCT imaging devices, discuss the technical challenges, and present the potential value in the clinical setting, especially in patients receiving medical or interventional CAD management.  相似文献   
54.
BackgroundNo established methodology exists for diagnosis of aortic stenosis (AS) using focused cardiac ultrasound (FOCUS). We evaluated the diagnostic accuracy of our developed visual AS score for screening AS in an emergency department.MethodsSeventy-two emergency outpatients with suspected cardiovascular disease were studied. Emergency physicians assessed the visual AS score in addition to conducting the standard FOCUS, and then the aortic valve area index (AVAI) was measured by expert sonographers in the echocardiography laboratory. AVAI values >0.85 cm2/m2, 0.6–0.85 cm2/m2, and <0.6 cm2/m2 were defined as no or mild AS, moderate AS, and severe AS, respectively.ResultsSeventeen (24%) patients had moderate or severe AS. Visual AS scores assessed by emergency physicians and by expert sonographers showed excellent agreement (κ = 0.93), and a strong association was noted between the visual AS score assessed by emergency physicians and the AVAI assessed by expert sonographers (R = –0.71, p < 0.0001). A visual AS score ≥3 assessed by emergency physicians had a sensitivity of 82%, specificity of 100%, positive predictive value of 100%, and negative predictive value of 95% for diagnosing moderate or severe AS. The prevalence of new-onset AS-related events during hospitalization was higher in patients with visual AS score ≥3 assessed by emergency physicians than in the remaining patients [7 (50%) vs. 2 (3%), p < 0.0001].ConclusionThe visual AS score is a useful AS screening tool for emergency physicians who are not expert cardiologists.  相似文献   
55.
We previously characterized the patients with autosomal recessive hypercholesterolemia (ARH) as having severe hypercholesterolemia and retarded plasma low-density lipoprotein (LDL) clearance despite normal LDL receptor (LDLR) function in their cultured fibroblasts, and we identified a mutation in the ARH locus in these patients. ARH protein is an adaptor protein of the LDL and reportedly modulates its internalization. We developed ARH knockout mice (ARH-/-) to study the function of this protein. Plasma total cholesterol level was higher in ARH-/- mice than that in wild-type mice (ARH+/+), being attributed to a 6-fold increase of LDL, whereas plasma lipoprotein was normal in the heterozygotes (ARH+/-). Clearance of 125I-LDL from plasma was retarded in ARH-/- mice, as much as that found in LDLR-/- mice. Fluorescence activity of the intravenously injected 1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate (DiI)-LDL was recovered in the cytosol of the hepatocytes of ARH+/+ mice, but not in those of ARH-/- or LDLR-/- mice. Also, less radioactivity was recovered in the liver of ARH-/- or LDLR-/- mice when [3H]cholesteryl oleyl ether (CE)-labeled LDL was injected. In contrast, uptakes of [3H]CE-labeled LDL, 125I-LDL, and DiI-LDL were all normal or slightly subnormal when the ARH-/- hepatocytes were cultured. We thus concluded that the function of the hepatic LDLR is impaired in the ARH-/- mice in vivo, despite its normal function in vitro. These findings were consistent with the observations with the ARH homozygous patients and suggested that certain cellular environmental factors modulate the requirement of ARH for the LDLR function.  相似文献   
56.
We describe a gastric carcinoma cell line that has been maintained in vitro for more than 10 years and retains the capacity to produce a large amount of alpha-fetoprotein. This cell line was isolated from a metastatic lymph node of a 63-year-old male patient with advanced gastric carcinoma (T2N3P0H0M0) who showed high serum levels of alpha-fetoprotein. The primary tumor was moderately differentiated tubular adenocarcinoma and the lymph node was poorly differentiated adenocarcinoma without any particular pattern. The cultured cells grew as densely packed islet-like colonies with small polygonal cells. Electron microscopy revealed cells abundant in cytoplasmic organelles, with some cellular attachments being tight with junctional complexes and some being loose across intercellular spaces. The free cell surface had microvilli. The population doubling-time was 152 h at passage 58. Chromosomal analysis revealed the modal number to be 77, with numerous karyotype abnormalities. The tumorigenicity of the cultured cells in athymic nude mice was positive only when they were subcutaneously transplanted beneath a plastic plate, but when the cells were transplanted subcutaneously or administered by intrasplenic injection in intact or weakly irradiated nude mice, no tumorigenicty was shown. The cell line produced tumor-associated antigens, such as alpha-fetoprotein, carcinoembryonic antigen, and tissue polypeptide antigen. This cell line may be useful for comparative studies of different types of gastric carcinoma and alpha-fetoproteins of different origins.  相似文献   
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58.
Sixty-one consecutive patients with multiple myeloma were studied with magnetic resonance (MR) imaging of the spine. Sagittal T1-weighted and short inversion time (TI) inversion recovery (STIR) images were obtained. The MR patterns of the bone marrow were classified as diffuse (D) ( n  = 26), nodular (N) ( n  = 11), D + N ( n  = 13) or normal (n) ( n  = 11). Abnormal patterns were seen in 50 (82%) of the 61 patients. Correlations were found between the MR imaging patterns and some laboratory findings (WBC, haematocrit, platelet count, serum albumin, and percentage of marrow plasmacytosis). The survival of the patients with abnormal MRI patterns was significantly poorer than that of the patients with normal patterns. However, the survival of patients with a nodular pattern did not differ from those with a normal pattern. The MR imaging pattern of the bone marrow in patients with multiple myeloma is a useful factor in the assessment of prognosis.  相似文献   
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60.
The aim of this study was to examine the histopathological features of the bronchi in patients with severe bronchial asthma. Seventy-four autopsy cases of death from severe bronchial asthma were analyzed statistically. The areas of the bronchial wall, smooth muscle, bronchial glands, basement membrane, and bronchial bore, were measured at the level of the subsegmental bronchi. Normal lungs from 34 autopsy cases without any respiratory pathology were used as controls. All of these areas but the last were significantly increased in severe bronchial asthma. The bronchial bore area was significantly decreased. Moreover, the above areas in low and moderate goblet cell hyperplasia cases were compared with those in high goblet cell hyperplasia cases. In the latter, the areas of the smooth muscle, bronchial glands and basement membrane were significantly elevated and those of the bronchial bore were significantly decreased. Finally, the areas of the bronchial bore, smooth muscle and bronchial glands were also compared between groups presenting with three different levels of basement membrane thickening, but no significant difference was noted. Further study to examine the precise morphological changes is needed to elucidate the characteristics of bronchi in severe bronchial asthma patients.  相似文献   
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