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951.
A primary hepatic carcinoid tumor arising in a 77-year-old woman is reported. The patient was admitted with a huge tumor in the right lobe of the liver and treated by an extended right lobectomy of the liver. Light microscopic findings showed that the tumor cells had small oval-shaped nuclei and eosinophilic cytoplasm with small granules forming trabecular, glandular, and rosette patterns. Immunohistochemically, tumor cells were stained positive with neuron-specific enolase and synaptophysin and were stained slightly positive with chromogranin and carcinoembryonic antigen. Careful examination before and after the operation revealed no other origin of the tumor. Based on the findings, the liver tumor was diagnosed as a primary carcinoid. The clinical features and diagnosis of this rare tumor are discussed in this report.  相似文献   
952.
Institutional review board approval and patient informed consent were obtained. Radiofrequency ablation in a total of 10 sessions was performed for each mediastinal lymph node metastasis from esophageal cancer that had a mean largest diameter of 2.2 cm +/- 0.6 (standard deviation) in seven male patients (mean age, 59 years). During ablation, cooling and temperature of the tracheal mucosa were monitored in the proper position in eight of the 10 sessions; in the other two sessions, monitoring was not done because of tracheal stenosis (perforation resulted). Three of the four lymph nodes that were 2.0 cm or smaller in largest diameter showed no evidence of local progression for at least 1 year since ablation; all three of the nodes greater than 2.0 cm in largest diameter progressed within 6 months. The 1-year survival rate was 60%; the median survival time was 13 months. Radiofrequency ablation may be effective for local control of small metastatic mediastinal lymph nodes, and cooling and temperature monitoring of the tracheal mucosa in the proper position may prevent thermal tracheal damage.  相似文献   
953.
OBJECTIVE: Accurate baseline staging is necessary to appropriately treat pancreatic cancer. The present study was undertaken to evaluate the clinical contribution of whole body FDG-PET to the detection of distant metastasis in pancreatic cancer. METHODS: A total of consecutive 42 patients with previously untreated pancreatic cancer were examined. Whole body FDG-PET imaging for initial staging was performed with a 3D acquisition and iterative reconstruction on Siemens ECAT HR+ scanner at 1 hour post 185-200 MBq 18F-FDG injection. PET findings were correlated with clinical and radiological data to determine the impact of PET on staging. RESULTS: In 16 patients, there were one or more sites of metastasis based on clinical data. FDG-PET correctly identified the presence of metastasis in 13 of 16 patients and its absence in 23 of the remaining 26 patients. Thus, FDG-PET missed 4 metastatic sites in 4 patients (liver and lung metastasis). FDG-PET correctly identified 8 metastatic sites in 7 patients (peritoneal dissemination and liver, bone and supraclavicular lymph node metastasis), which were missed on CT imaging. Based on whole body FDG-PET, the clinical stage was changed in 5 of 42 patients (11.9%). CONCLUSIONS: These results suggest that FDG-PET and CT appear to have a complementary role in the detection of distant metastasis in patients with pancreatic cancer.  相似文献   
954.
The purpose of this study was to evaluate the durability of tungsten carbide burs for the fabrication of titanium crowns using two dental CAD/CAM systems (DECSY, Digital Process, Japan and Cadim, Advance, Japan). A tungsten carbide bur in each system was examined and used without fracture to fabricate 51 titanium crowns. For both systems tiny chips were found on the bur blade at the 11th machining. These chips gradually enlarged as the number of machining times increased. At the first machining no significant difference in the average surface roughness was found on the crown between the two systems (1.6 microm for DECSY and 1.2 microm for Cadim). The cutting grooves became dull and the average surface roughness increased as the number of machining times increased. It is concluded that the tungsten carbide burs for both systems can be used to fabricate up to 51 titanium crowns.  相似文献   
955.
Although adrenomedullin (ADM) is a potent vasodilating peptide reported to play a possible role in the mechanisms of fetal lung differentiation and maturation, the ADM blood level in fetuses and in neonates with persistent pulmonary hypertension (PPHN) and pulmonary hypoplasia is not known. Therefore, we examined 15 patients with PPHN: 10 with congenital diaphragmatic hernia, four with congenital cystic adenomatoid malformation of the lung, and one with misalignment of pulmonary vessels with alveolar capillary dysplasia. Eight surgical patients with neonatal conditions such as intestinal atresia served as controls. Blood samples were drawn from the umbilical artery and vein at birth, and arterial blood was drawn from patients with PPHN on the 3rd and 6th days after birth. Plasma levels of ADM were measured by radiometric assay. Plasma levels of ADM in the umbilical artery and vein were elevated in patients with PPHN compared with controls, and in all groups the levels in the umbilical vein were higher than those in the umbilical artery. The arterial levels in patients with poor prognoses were elevated on the 3rd and 6th days after birth compared with those in survivors. These results indicate that ADM may be involved in the pathophysiology of PPHN and in the mechanisms of lung differentiation and/or maturation.  相似文献   
956.
Hereditary non-polyposis colorectal cancer (HNPCC), also called Lynch syndrome, is an autosomal dominantly inherited disorder of cancer susceptibility. Patients with HNPCC exhibit an increased risk for HNPCC-associated extracolonic tumors such as cancer of the endometrium. HNPCC is associated with germline mutations in DNA mismatch repair (MMR) genes: hMLH1, hMSH2 and hMSH6. Here, we describe two Japanese kindreds (0.5%) who met the new clinical criteria for HNPCC, Amsterdam criteria II, from among 375 endometrial cancer patients treated at Keio University Hospital from 1990 to 2002. From these results, it was found that female HNPCC patients comprised approximately 0.5% of all endometrial cancer patients. Decreased expression of two MMR gene protein products (hMLH1 and hMSH6) was confirmed immunohistochemically in these two endometrial tumors in HNPCC kindreds. This case report provides important information on Japanese HNPCC patients occurring endometrial cancer.  相似文献   
957.
Background and Aims  We evaluated the efficacy of the transport oocyte/embryo frozen/thawed embryo transfer method, in which oocytes or embryos were transported from satellite clinics to the main assisted reproductive technology (ART) center, and surplus embryos were placed in cryopreservation. Methods  We evaluated 41 cycles in 34 patients in the transport oocyte group (TO group). In the TO group the oocytes were collected at the satellite clinics, transported to the main ART center and underwentin vitro fertilization or intracytoplasmic sperm injection. Surplus embryos were used for frozen/thawed embryo transfer. We also evaluated 17 cycles in 10 patients in the transport embryo group (TE group), where surplus embryos were transported to the main ART center and used for frozen/thawed embryo transfer; and 189 cycles in 134 patients in the center group (C group), where surplus embryos collected at the same time at the main ART center were used for frozen/thawed embryo transfer. Oocytes were transported from satellite clinics in HEPES buffered human tubal fluid (HTF) culture medium, and embryos in 30% synthetic serum substitute + HEPES buffered HTF, using a portable incubator we devised. Results  The proportions of undamaged embryos after freeze/ thawing were 47% for the C group, 46% for the TO group, and 46% for the TE group. The numbers of embryos transferred were 2.0 ± 0.7 for the C group, 2.0 ± 0.6 for the TO group, and 2.2 ± 0.4 for the TE group. The rate of embryo transfer was 63% for the C group, 68% for the TO group, and 76% for the TE group. Pregnancy rates per patient were 16% for the C group, 24% for the TO group, and 40% for the TE group. The embryo survival rates (number of embryos with ≥50% viable blastomeres/total number of embryos) were 55% for the C group, 60% for the TO group, and 54% for the TE group. No significant differences were seen between the C group and either the TO or TE groups in any of these parameters. Conclusions  Favorable results were achieved with the transport oocyte/embryo frozen/thawed embryo transfer method, and it is suitable for widespread clinical application.  相似文献   
958.
To analyze the biology of small (20 mm or less) advanced colorectal carcinomas (SAC), 24 cases, 22 small early colorectal carcinomas (SEC) of similar size, and 52 advanced colorectal carcinomas (AC) were studied. The proliferative (Ki-67) labeling index for SAC was 65.9+/-17.1%, significantly higher than those for SEC (30.9+/-13.7%) or AC (43.0+/-17.1%) (P < 0.01). Matrix metalloproteinase (MMP)-9 and tissue inhibitors of metalloproteinase (TIMP)-2 expressions for SAC were 62.5 and 79.2%, respectively, significantly higher than those for SEC (4.5, 13.6%) or AC (21, 33%) (P < 0.01). Small advanced carcinomas have higher invasiveness than SEC or AC and may represent a different type of cancer.  相似文献   
959.
What types of colorectal cancer overexpress the MAGE protein?   总被引:1,自引:0,他引:1  
BACKGROUND/AIMS: Tumor-specific antigens such as Melanoma-associated antigens could be attractive targets for immunotherapy. It will be a great help for cancer immunotherapy to distinguish what types of tumor expresses tumor-specific antigen. METHODOLOGY: We investigated the expression pattern of MAGE-A1 by immunohistochemical typing methods in human colorectal cancers obtained from consecutive patients undergoing surgical treatment at the hospital of the University of Tokyo. RESULTS: In 35 of 89 cases (39%), MAGE-A1 positive immunoreactivity was detected in the malignant glands. MAGE-A1 positive immunoreactivity was significantly higher among the patients under the age of 70 than among those 70 years of age and older (p=0.04). Among the patients under the age of 70, the tumors located in the distal colon (descending colon, sigmoid colon and rectum) showed significantly more positive MAGE-A1 immunoreactivity than those in the proximal colon (cecum, ascending colon and transverse colon) (p=0.04). The expression pattern of MAGE-A1 was not associated with gender, size, depth, histological type, vessel invasion, lymphatic invasion, lymph nodal invasion or stage of disease. CONCLUSIONS: Relatively better results can be expected with MAGE-A1 immunotherapy among patients with distal colon cancer under the age of 70.  相似文献   
960.
BACKGROUND: Both propofol and thiamylal inhibit adenosine triphosphate-sensitive potassium (KATP) channels. In the current study, the authors investigated the effects of these anesthetics on the activity of recombinant sarcolemmal KATP channels encoded by inwardly rectifying potassium channel (Kir6.1 or Kir6.2) genes and sulfonylurea receptor (SUR1, SUR2A, or SUR2B) genes. METHODS: The authors used inside-out patch clamp configurations to investigate the effects of propofol and thiamylal on the activity of recombinant KATP channels using COS-7 cells transfected with various types of KATP channel subunits. RESULTS: Propofol inhibited the activities of the SUR1/Kir6.2 (EC50 = 77 microm), SUR2A/Kir6.2 (EC50 = 72 microm), and SUR2B/Kir6.2 (EC50 = 71 microm) channels but had no significant effects on the SUR2B/Kir6.1 channels. Propofol inhibited the truncated isoform of Kir6.2 (Kir6.2DeltaC36) channels (EC50 = 78 microm) that can form functional KATP channels in the absence of SUR molecules. Furthermore, the authors identified two distinct mutations R31E (arginine residue at position 31 to glutamic acid) and K185Q (lysine residue at position 185 to glutamine) of the Kir6.2DeltaC36 channel that significantly reduce the inhibition of propofol. In contrast, thiamylal inhibited the SUR1/Kir6.2 (EC50 = 541 microm), SUR2A/Kir6.2 (EC50 = 248 microm), SUR2B/Kir6.2 (EC50 = 183 microm), SUR2B/Kir6.1 (EC50 = 170 microm), and Kir6.2DeltaC36 channels (EC50 = 719 microm). None of the mutants significantly affects the sensitivity of thiamylal. CONCLUSIONS: These results suggest that the major effects of both propofol and thiamylal on KATP channel activity are mediated via the Kir6.2 subunit. Site-directed mutagenesis study suggests that propofol and thiamylal may influence Kir6.2 activity by different molecular mechanisms; in thiamylal, the SUR subunit seems to modulate anesthetic sensitivity.  相似文献   
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