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131.
132.
Annals of Nuclear Medicine - The Oncotype DX (ODX) estimates the 10-year risk of metastasis or recurrence of breast cancer and indicates whether chemotherapy is likely to be effective; however, the...  相似文献   
133.
For some time, anomalous serological reactions have been observed when the same anti-Swa sera are tested against red cells from different individuals reported as Sw(a+). A comparative collaborative study using the same collection of Sw(a+) cells and anti-Swa sera was undertaken by 4 reference laboratories, and it was found that Swa represents a heterogeneous group of antigens that can be subdivided into two categories. Both categories, Sw(a+) 700:41 and Sw(a+) 700:-41, were shown to be inherited.  相似文献   
134.
135.
p53 point mutations in primary human gastric carcinomas   总被引:12,自引:0,他引:12  
Summary p53 point mutations in primary gastric carcinomas were analyzed by performing cDNA deoxynucleotide sequencing of the gene. Out of 16,9 (56.3%) primary gastric carcinoma cases, including early cancer, showed one or more p53 point mutations in their open-reading frame, and 4 out of 9 cases had a p53 point mutation within highly conserved domains. The characteristics of the p53 mutation spectrum observed in primary tumors were (a) frequent mutation at an A:T pair (50%, 7 out of 14 mutations), (b) high transversion incidence (29%, 4 out of 14 mutations), (c) no transition at CpG, and (d) no G:C to T:A transversion. Our results suggest that p53 mutation is a common event in gastric carcinoma occurring from the early stage of progression with its specific mutation spectrum.Abbreviation PCR-SSCP polymerase chain reaction single-strand conformation polymorphism  相似文献   
136.
A 56-year-old Japanese man with hypertension presented with a 10 days history of high fever, right and left upper quadrant tenderness. An abdominal ultrasonography and computerized tomographic scan revealed a large collection in the right lobe of the liver that was consistent with an abscess. A drainage catheter was placed and purulent fluid was drained. Cultures of the fluid and blood were positive for a strain of ampicillin-resistant Klebsiella pneumoniae. Six days after admission, paraplegia and urinary retention were found. On the neurological examination, deep tendon reflexes of the lower extremities were absent bilaterally. Magnetic resonance imaging scan detected thoracic spinal epidural abscess and paraspinal abscess. He received the emergent decompressive laminectomy. Culture of surgical specimen grew ampicillin-resistant K. pneumoniae. The patient was treated with biapenem intravenously. Thereafter, clinical symptoms improved gradually and he was removed to the professional hospital to continue rehabilitation for gait disturbance on hospital day 147.  相似文献   
137.
Objectives:   Macrophages (Mφs) have various functions and play a critical role in host defense and the maintenance of homeostasis. Mφs exist in every tissue in the body, but Mφs from different tissues exhibit a wide range of phenotypes with regard to their morphology, cell surface antigen expression and function, and are called by different names. However, the precise mechanism of the generation of macrophage heterogeneity is not known. In the present study, the authors examined the functional heterogeneity of Mφs generated from human monocytes under the influence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and macrophage-CSF (M-CSF).
Methodology:   CD14 positive human monocytes (Mos) were incubated with M-CSF and GM-CSF for 6–7 days to stimulate the generation of M-CSF-induced monocyte-derived Mφs (M-Mφs) and GM-CSF-induced monocyte-derived Mφs (GM-Mφs), respectively. The expression of cell surface antigens and several functions such as antigen presenting cell activity, susceptibility to oxidant stress, and the susceptibility to HIV-1 and mycobacterium tuberculosis infection were examined.
Results:   GM-Mφs and M-Mφs are distinct in their morphology, cell surface antigen expression, and functions examined. The phenotype of GM-Mφs closely resembles that of human Alveolar-Mφs (A-Mφs), indicating that CSF-induced human monocyte-derived Mφs are useful to clarify the molecular mechanism of heterogeneity of human Mφs, and GM-Mφs will become a model of human A-Mφs.  相似文献   
138.
Thrombopoietin stimulated blast colony formation in 11/20 acute myelogenous leukaemia (AML) patients studied. The FAB subtypes of the blasts responding to thrombopoietin were not restricted to those of the megakaryocyte lineage, but also included M1–M5 AML blasts. The morphology of colony cells produced by megakaryocytic blasts showed megakaryocytoid features, whereas colony cells produced by M1–M5 AML blasts remained myeloblasts. An increase in CD41 was observed in the cells of colonies produced by blasts from the megakaryocyte lineage involving leukaemia and chronic myeloid leukaemia in blastic crisis. Thrombopoietin receptor was observed on leukaemic blasts which formed colonies following incubation with thrombopoietin.  相似文献   
139.
Summary N-Methyl-N-nitrosourea (MNU) is a potent carcinogen in various sites of experimental animals and induces thymic lymphoma in rats, which has long been hard to induce by any carcinogen. To analyze the action of MNU on thymocytes, DNA strand breaking in thymocytes from the MNU-treated rat and that in MNU-treated cultured thymocytes were assayed. Fluorometric analysis of DNA unwinding (FADU assay), first reported by Birnboim and Jevcak to detect X-ray-induced DNA damage, was modified and applied to detect DNA damage in thymocytes treated with MNU in vitro or in vivo. In the present modified method, cell lysate was admixed with 0.15M sodium hydroxide, and DNA unwinding was processed at pH 12.0 for up to 2 h at 0° C in iced water. Double-stranded DNA remaining after alkaline reaction was detected by binding ethidium bromide and measuring its fluorescence. The severity of DNA damage, both in vivo and in vitro, depended on the MNU concentration. In addition, the sequential survival rate and cell-size distribution of thymocytes treated with MNU in vitro were investigated. A close relationship between the severity of DNA damage and cell death was demonstrated in MNU-treated thymocytes, and DNA damage by a non-cell-killing dose of MNU was detected with this FADU assay. MNU-induced cell death is not programmed as in apoptosis, which is caused in thymocytes physiologically, immunologically and by X-ray irradiation or corticoids.Abbreviations used MNU N-methyl-N-nitrosourea - FADU fluorometric analysis of DNA unwinding - PBS calcium- and magnesium-free phosphate-buffered saline  相似文献   
140.
OBJECTIVE: To compare the efficacy and safety of two antiplatelet regimens, ticlopidine alone (200 mg daily) and ticlopidine (100 mg daily) plus aspirin (81 mg daily), in patients with ischemic stroke from the Tokai district of Japan. METHODS: A randomized comparative study was performed from April 1992 until December 1995, with follow-up for an average of 1.59 years (maximum: 3 years). Statistical analysis was done on 270 eligible patients (138 treated with ticlopidine alone and 132 treated with ticlopidine plus aspirin). PATIENTS: A total of 276 patients who had cerebral infarction within the previous 1 to 6 months, or one or more transient ischemic attacks within the previous 3 months. RESULTS: The incidence of ischemic and hemorrhagic stroke, myocardial infarction, and other vascular events was 10.1% (n = 14) in the ticlopidine group and 9.8% (n = 13) in the ticlopidine plus aspirin group, showing no significant difference (p = 0.933). There was also no significant difference in the event-free rate between the two groups (p = 0.5003, Kaplan-Meier analysis and log-rank test). Regarding serious adverse reactions, neutropenia occurred in one patient from the ticlopidine group, while gastric ulcer and thrombocytopenia occurred in one patient each from the ticlopidine plus aspirin group. CONCLUSION: We conclude that both antiplatelet regimens are comparable in efficacy and safety for preventing the recurrence of ischemic stroke.  相似文献   
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