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1.
Three patients with dysphagia caused by compression of the distal esophagus by a tortuous nonaneurysmal atherosclerotic aorta are described. All three patients were elderly women; systemic hypertension and cardiomegaly were present in two patients. Barium studies of the esophagus showed displacement and compression of the distal esophagus by the thoracic aorta. Debilitating dysphagia was treated surgically in one patient. The other two patients had milder symptoms and were managed conservatively. Esophageal manometry in these three patients showed superimposed pulsations and elevated intraluminal pressure just proximal to the lower esophageal sphincter. To evaluate the significance of these manometric findings and their correlation with clinical symptoms, we reviewed manometric tracings in 47 normal subjects. Ten of these subjects had an elevation of baseline intraluminal esophageal pressure as a result of superimposed vascular pulsations. We conclude that (1) compression of the distal esophagus by a tortuous atherosclerotic aorta in the appropriate setting can lead to clinically significant dysphagia and (2) a manometric finding of vascular compression of the esophagus does not necessarily correlate symptomatic dysphagia.  相似文献   
2.
Regarding peroral cholangioscopy (POCS) for biliary disease, due to the recent appearance of a video cholangioscope that can obtain high‐quality images, it is possible to observe subtle changes of the biliary mucosa. In addition to the conventional observation method using POCS, the biliary mucosa with also observed with narrow band imaging (NBI) in one case of chronic cholangitis and four cases of extra hepatic bile duct tumor (three surgical cases). In the conventional observation method, the vessels in the surface layer of the biliary mucosa could be observed more clearly using NBI. In one case in which a tumor was observed, the irregularity of the biliary mucosa became clear on NBI, and the vessels inside a papillary tumor could also be easily observed. In another case of bile duct tumor, the conventional observation method showed a region in the proximity of the tumor where the vessels could not be seen clearly, but they could be seen clearly on NBI. In all of the cases, the bile juice was seen as red on NBI, which disturbed the observation. With POCS using NBI, it was possible to observe the vessels and irregularities in the surface layer of the biliary mucosa more clearly than with conventional observation methods.  相似文献   
3.
A case of an odontogenic tumor which invaded the intracranial space from the mandible is reported. Judging from the radiographic images it was similar to a malignant tumor. The patient died 17 years after the first visit. According to the final pathological diagnosis, it was malignant odontogenic mixed tumor of low grade which did not belong to any of the WHO classification.  相似文献   
4.
A 64-year-old man was admitted for further examinations of a liver tumor. The patient was diagnosed as chronic hepatitis C complicated with advanced hepatocelluar carcinoma (HCC) with left portal vein tumor thrombosis. As he refused surgical treatment, hepatic arterial infusion chemotherapy (HAIC) using cisplatin and 5-fluorouracil was performed initially. Administration of ursodesoxycholic acid (UDCA) was also started. Following HAIC, microwave coagulation therapy for residual tumor was added. Consequently, viable lesions of HCC disappeared completely. At present, after more than 8 years, neither signs of tumor recurrence, nor elevation of hepatic enzymes has been observed. Although the precise reason for long survival of this patient is not known, we speculate that suppression of levels of hepatic enzymes, as well as HAIC for subclinical intrahepatic metastasis, contributed to the good outcome. Therapeutic strategy for hepatic inflammation seems to be important for long-term prevention of hepatocarcinogenesis.  相似文献   
5.
Aim: Hepatitis C virus (HCV) 1b is resistant to standard interferon therapy and has a high risk of developing into hepatocellular carcinoma at the late stage of infection. Therefore, new therapeutic modalities for HCV1b infection must be developed. One approach would be active specific immunotherapy with highly immunogenic HCV1b peptides. Methods: HCV1b-derived 44 synthetic peptides were selected based on their binding scores to HLA-A24. Peptide-specific IgG were measured by ELISA. Peptide-specific cytotoxic T-lymphocytes (CTLs) were induced in vitro by repeated peptide-stimulation. Results: We identified three novel candidate peptides of HCV1b proteins containing HLA-A24 binding motifs. Each of them had the ability to induce HLA-A24-restricted and peptide-specific CTL activity, and IgGs specific to each of them were detected in the plasma of HCV1b patients. Among these three peptides, a peptide NS5A 2132-2142 was recognized by both cellular and humoral immunities in the majority of blood samples of patients tested. More importantly, the peptide-stimulated peripheral blood mononuclear cells (PBMCs) showed cytotoxicity against cells cotransfected with NS5A and HLA-A2402 genes in an HLA-restricted manner. This is an additional report to our previous study. Conclusion: These findings may provide a new insight into the development of a peptide-based specific immunotherapy for HCV1b-infected patients.  相似文献   
6.
To examine species differences in the distribution pattern of guanosine triphosphate (GTP)-binding protein (Go) within the vertebrate retina, paraffin-embedded retinae from a number of vertebrate species, including the goldfish, frog, turtle, chicken, monkey, and human, were immunohistochemically stained with affinity-purified antibody against the alpha-subunit of Go. Go-immunoreactive products were found to be located in the neuropil, but not in the cell bodies of neurons, in the retina of all these species. However, some species differences were observed. In the frog, monkey and human, the inner plexiform layer (IPL) was homogeneously stained with this antibody, but in the goldfish, turtle and chicken, the IPL was heterogeneously stained. In the frog, chicken, turtle and human, the outer plexiform layer (OPL) was densely stained with this antibody, but in the goldfish and monkey, the OPL was rather faintly immunoreactive to the antibody. In the goldfish, monkey and human, the outer nuclear layer (ONL) was not immunoreactive to the Go-antibody, whereas in the frog, turtle and chicken, the ONL was immunoreactive to it. The implications of these species differences in Go localization in the vertebrate retina are discussed.  相似文献   
7.
Ca(++)-dependent monoclonal antibody specific to gamma-carboxyglutamic acid (Gla) domain of protein C was produced. It did not cross-react to the other vitamin K-dependent plasma proteins but to protein C of the other species. Using this monoclonal antibody, PC01, rabbit (170 micrograms), rat (60 micrograms) and mouse (40 micrograms) protein Cs were isolated from 100 ml of their plasma by affinity chromatography. All of these protein Cs were two chain form linked by disulfide bond as well as human protein C and activated by thrombin-thrombomodulin complex. Rat and mouse protein Cs showed similar characters to human protein C. On the other hand rabbit protein C had different M(r) of heavy and light chains and showed lower anticoagulant activity compared with human protein C.  相似文献   
8.
A 49-year-old woman was referred to our hospital with complaints of epigastric colicky pain and high fever. Abdominal computed tomography and ultrasonography showed a solid tumor in the lower abdomen. Laparotomy revealed a neoplastic mass arising in Meckel's diverticulum; therefore, a segment of the ileum, including the tumor-possessing diverticulum, was resected with a lymph node dissection. A histologic examination confirmed the lesion to be leiomyosarcoma. In the English literature, 59 cases of leiomyosarcoma in Meckel's diverticulum were reported from 1941 to 1994. The majority of patients were in their 4th decade of life, with both sexes equally affected. The most frequent symptoms associated with this disease were abdominal pain with nausea, vomiting, and melena. The majority were larger than egg-size. Although Meckel's diverticulum is difficult to diagnose preoperatively, mesenteric arteriography may at times prove useful. The standard management of this particular tumor is wide segmental resection, including the tumor and diverticulum with lymph node dissection.  相似文献   
9.
Stress thallium-201 tomography was performed to compare the flow capacities of arterial and saphenous vein grafts in patients with coronary artery bypass grafting (CABG). One hundred and seven consecutive patients (95 male and 12 female; mean age 58±9.1 years) underwent exercise-redistribution 201Tl myocardial single-photon emission tomography 4–5 weeks after CABG. When a reversible perfusion defect was present in the area covered by a patent bypass graft, the flow capacity of the graft was defined as insufficient. Of all 285 grafts, 211 were considered as complete bypass. Reversible perfusion defects were present in 29 (27%) of 108 myocardial areas supplied by patent arterial grafts but in only 5 (5%) of 103 myocardial areas supplied by patent saphenous vein grafts (P<0.0001). In the LAD area reversible defects were observed in 22 of 82 areas covered by arterial grafts, in contrast to only 1 of 29 areas covered by venous grafts (P<0.01); in the RCA area reversible defects were observed in 7 of 17 and 4 of 41 areas respectively (P<0.01). There was no difference between the native coronary artery stenosis bypassed by patent arterial and venous grafts (88%±12% vs 86%±14% respectively, P=0.27). In conclusion, flow capacities during peak myocardial demand were more frequently insufficient in arterial bypass grafts than in saphenous vein grafts. Received 23 May and in revised form 7 August 1997  相似文献   
10.
Localization of bone marrow-originated cells in the central nervous system (CNS) of the rat was investigated by using bone marrow chimeras. In order to do this, Lewis rats which carry major histocompatibility complex (MHC) class I antigens haplotype 1 (RT1.Al) were reconstituted with (Lew X PVG)F1 (RT1.Al/c) bone marrow cells after lethal irradiation. Transferred bone marrow cells were detected by immunohistochemical staining using a monoclonal antibody, OX27, specific for haplotype c of rat MHC class I antigens (RT1.Ac). The spleen and thymus of chimeric rats were fully reconstituted with transferred F1 cells 4 weeks after bone marrow transplantation. At this stage, mononuclear cells in the subarachnoid space of the CNS expressed OX27 antigen indicating that they were of bone marrow origin. A few OX27-positive blood cells were scattered in the CNS parenchyma 4-12 weeks after reconstitution. Ramified microglia, however, remained OX27-negative. Bone marrow-derived microglia were not observed throughout the period of examination until 24 weeks. In addition, experimental allergic encephalomyelitis (EAE) was induced in chimeric rats in order to augment the expression of MHC class I antigens on microglia. Even under this condition, no OX27-positive microglia were observed. Taken together, ramified microglia might be of neuroectodermal origin and there is little possibility that the microglia are derived from the bone marrow. However, if the ramified microglia are derived from blood cells, the microglia may be expected to have characteristic cell kinetics from the following points: (1) the precursor cells of the microglia may enter the CNS only at the perinatal stage; and (2) even under the condition in which lymphocytes and macrophages enter the CNS as observed in EAE, the precursor cells of the microglia are not supplied from the blood.  相似文献   
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