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81.
The current article reviews the most recent literature addressing the definitions, ethical considerations, and potential strengths and limitations of online therapy. In addition, a framework is provided for how to conceptualize and categorize different aspects of online therapy for research purposes. Relevant studies of both online and face-to-face therapy as well as suggestions for future research are outlined.  相似文献   
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83.
HYPOTHESIS: En bloc esophagectomy (EBE) provides improved survival over transhiatal esophagectomy (THE) in patients with similarly sized transmural tumors (T3) and lymph node metastases (N1). DESIGN: A retrospective case-control study of 2 methods of esophageal resection for cancer. SETTING: University hospital (tertiary referral center for esophageal disease). PATIENTS: There were 49 patients (27 who underwent EBE and 22 who underwent THE) with similar T3 N1 disease and the following matched criteria: tumors of similar size and location, more than 20 lymph nodes in the surgical specimen, R0 resection, no previous chemotherapy or radiation therapy, and follow-up until death or for a minimum of 5 years.Main Outcome Measure Survival adjusted for differences in demographic and patient characteristics. RESULTS: The number of nodes harvested was greatest after EBE vs THE (median, 52 vs 29 [range, 21-85 vs 20-60]; P<.001). The median number of involved nodes was similar after EBE vs THE (median, 5 vs 7 [range, 1-19 vs 1-16]). The only 2 independent factors that affected survival in a Cox analysis were the number of involved lymph nodes (P =.01) and the type of resection (P =.03). Patients who underwent EBE had a survival benefit over those who underwent THE (P =.01). The survival benefit of EBE was seen only in patients with fewer than 9 involved lymph nodes (P<.001). CONCLUSION: En bloc esophagectomy confers a better survival than THE in patients with T3 N1 disease and fewer than 9 lymph node metastases.  相似文献   
84.
In previous rat studies, the use of mixed allogeneic chimerism (MAC) to induce host tolerance to hind limb allografts has resulted in severe graft-versus-host disease (GVHD). The purpose of this study was to determine if immunocompetent cells in bone marrow (BM) and/or lymph nodes (LNs) of transplanted limbs were responsible for inducing GVHD in mixed chimeric hosts. [ACIWistar Furth] chimeric rats received ACI hind limbs that were non-irradiated, irradiated (1050 cGy) or lymphadenectomized. Rejection, GVHD and donor chimerism was assessed. Chimeric hosts rejected none of their limbs. However, hosts of non-irradiated hind limbs succumbed to GVHD 22.4±0.8 days after transplantation. In contrast, chimeras that received irradiated or lymphadenectomized ACI hind limbs showed no clinical or histological signs of GVHD at 5 months. We conclude that mixed chimeric hosts are susceptible to GVHD due to the immunocompetent cell load provided by the LNs, not the BM, of hind limb allografts.Abbreviations BM Bone marrow - CPM Counts per minute - CTA Composite tissue allograft - FACS Fluorescence activated cell sorter - FITC Fluorescent iso-thiocyanate - GVH Graft-versus-host - GVHD Graft-versus-host disease - HVG Host-versus-graft - LN Lymph node - MAC Mixed allogeneic chimerism - MHC Major histocompatibility complex - MLR Mixed lymphocyte reaction - MoAb Monoclonal antibody - PBL Peripheral blood lymphocytes - SEM Standard error of mean - TBI Total body irradiation - TCD T-cell depletion/T-cell depleted - TCR T-cell receptor  相似文献   
85.
We have investigated the effect of mast cell activation induced by immunological and non-immunological stimuli on the sensitivity to adenosine of parenchymal strips prepared from lungs removed from Brown Norway (BN) rats actively sensitized to ovalbumin. Strips responded to ovalbumin with a biphasic contractile response. Responses to adenosine were markedly increased 30 min after ovalbumin. The first phase of the response to ovalbumin was abolished by the 5-hydroxytryptamine (5-HT)2 receptor antagonist, methysergide and unaffected by the cysteinyl leukotriene receptor antagonist, iralukast. The second phase was abolished by iralukast and unaffected by methysergide. The response to adenosine was markedly reduced by methysergide but not significantly altered by iralukast. Compound 48/80 (condensation product of N-methyl-p-methoxyphenylethylamine with formaldehyde) induced methysergide-sensitive contractions of the parenchymal strip and potentiated adenosine; the augmented response to adenosine was blocked by methysergide. Thus, activation of mast cells in the lung by either immunological or non-immunological stimuli results in augmentation of the mast cell-mediated contractile response to adenosine.  相似文献   
86.
PURPOSE: There is now convincing evidence that prostate cancer cells lack the ability to produce and accumulate citrate. Using magnetic resonance spectroscopy imaging (MRSI), regions of absent or low citrate concentration in the prostate can be visualized at a resolution of a few mm. This new advancement provides not only a tool for early diagnosis and screening but also the opportunity for preferential targeting of radiation to regions of high tumor burden in the prostate. The differences in the shape and location of the prostate between MRSI imaging and treatment have been the major obstacle in integrating MRSI in radiation therapy treatment planning. The purpose of this study is to develop a reliable method for deforming the prostate and surrounding regions from the geometry of MRSI imaging to the geometry of treatment planning, so that the regions of high tumor burden identified by the MRSI study can be faithfully transferred to the images used for treatment planning. METHODS AND MATERIALS: Magnetic resonance spectroscopy imaging studies have been performed on 2 prostate cancer patients using a commercial MRSI system with an endorectal coil and coupling balloon. At the end of each study, we also acquired the MRI of the pelvic region at both the deformed state where the prostate is distorted by the endorectal balloon and the resting state with the endorectal balloon deflated and removed. The task is to find a three-dimensional matrix of transformation vectors for all volume elements that links the two image sets. We have implemented an optimization method to iteratively optimize the transformation vectors using a Newton-Ralphson algorithm. The objective function is based on the mutual information. The distorted images using the transformation vectors are compared with the images acquired at the resting conditions. RESULTS AND DISCUSSION: The algorithm is capable of performing the registration automatically without the need for intervention. It does not require manual contouring of the organs. By applying the algorithm to multiple image sets of different patients, we found a good agreement between the images transformed from those acquired at the deformed state and those acquired at resting conditions. The computation time required for achieving the registration is in the range of a half-hour (for image size: 256 pixels x 256 pixels x 25 slices). However, the space of registration can be restricted to speed up the process. CONCLUSION: In this article, we described a three-dimensional deformable image registration method to automatically transform images from the deformed imaging state to resting state. Our examples show that this method is feasible and useful to the treatment planning system.  相似文献   
87.
Three taeniid tapeworms infect humans in Asia and the Pacific: Taenia solim, Taenia saginata, and Taenia asiatica. Although there is continuing debate about the definition of a new species, phylogenetic analyses of these parasites have provided multiple lines of evidence that T. asiatica is an independent species and the sister species of T. saginata. Here we review briefly the morphology, pathology, molecular biology, distribution and control options of taeniasis/cysticercosis in Asia and the Pacific and comment on the potential role which dogs may play in the transmission of T. solium. Special attention is focused on Indonesia: taeniasis caused by T. asiatica in North Sumatra, taeniasis/cysticercosis of T. solium and taeniasis of T. saginata in Bali, and taeniasis/cysticercosis of T. solium in Papua (formerly Irian Jaya). Issues relating to the spread of taeniasis/cysticercosis caused by T. solium in Papua New Guinea are highlighted, since serological evidence suggests that cysticercosis occurs among the local residents. The use of modern techniques for detection of taeniasis in humans and cysticercosis in humans, pigs and dogs, with the possible adoption of new control measures will provide a better understanding of the epidemiology of taeniasis/cysticercosis in Asia and the Pacific and lead to improved control of zoonotic and simultaneously meat-borne disease transmission.  相似文献   
88.
In humans, group 1 CD1 glycoproteins present foreign and self lipid and glycolipid antigens to T-cells. Homologues of these molecules are not found in mice or rats but are present in guinea pigs (GPs). We examined CD1 and MHC class II expression in the central nervous system (CNS) of GPs sensitized for experimental autoimmune encephalomyelitis (EAE), an animal model of multiple sclerosis. In normal GPs and the uninflamed CNS, low-level MHC class II (MHC II) immunoreactivity occurred on vascular elements, meningeal macrophages and parenchymal microglial cells, whereas immunoreactivity for CD1 was absent. In the inflamed CNS, the majority of infiltrating cells were MHC II+ and microglia showed increased expression. CD1 immunoreactivity was detected on astrocytes and subsets of inflammatory cells Including B cells and macrophages. Minimal CD1 and MHC II co-expression was noted on inflammatory cells or glia. We conclude that group 1 CD1 molecules are strongly upregulated in the inflamed CNS on subsets of cells distinct from the majority of MHC II bearing cells. The expression of CD1 proteins in such lesions broadens the potential repertoire of antigens recognized at these sites and highlights the value of the GP as a model for studies of the relevance of CD1 molecules in host defense and autoimmune diseases.  相似文献   
89.
Alveolar and cystic hydatidosis are caused by infection with the larval stages of Echinococcus multilocularis and Echinococcus granulosus, respectively. A host-protective antigen has been identified in E. granulosus. Here we identify the presence of a closely related protein in E. multilocularis, characterize and express a cDNA encoding the antigen (designated EM95), determine the structure of the em95 gene, and demonstrate that the EM95 recombinant protein can be used to induce significant levels of protection against challenge infection with E. multilocularis eggs in mice.  相似文献   
90.
Definitive neonatal diagnosis of congenital adrenal hyperplasia (CAH) is frequently complicated by normal 17-hydroxyprogesterone levels in 21-hydroxylase-deficient patients, residual maternal steroids, and other interfering substances in neonatal blood. In an effort to improve the diagnosis, we developed a gas chromatography/mass spectrometry method for simultaneous measurement of 15 urinary steroid metabolites as early as the first day of life. Furthermore, we developed 11 precursor/product ratios that diagnose and clearly differentiate the four enzymatic deficiencies that cause CAH. Random urine samples from 31 neonatal 21-hydroxylase-deficient patients and 59 age-matched normal newborns were used in the development. Additionally, samples from two 11 beta-hydroxylase-deficient patients and one patient each for 17 alpha-hydroxylase and 3 beta-hydroxysteroid dehydrogenase deficiencies were used. The throughput for one bench-top gas chromatography/mass spectrometry instrument is 20 samples per day. Thus, this method affords an accurate, rapid, noninvasive means for the differential diagnosis of CAH in the newborn period without the need for invasive testing and ACTH stimulation.  相似文献   
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