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31.
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Ana Sion Ricardo Bruña Fernández Andrés Martínez Maldonado Isabel Domínguez Centeno Angel Torrado-Carvajal Gabriel Rubio Ernesto Pereda Rosa Jurado-Barba 《Journal of neuroscience research》2020,98(10):1857-1876
There is supporting evidence of alcohol negative effects on the brain: neuroimaging and psychophysiological studies finding anatomical and functional connectivity (FC) changes associated with the dependence process. Thus, the aim of this work was to evaluate brain FC and network characteristics of alcohol-dependent individuals in resting state. For this study, we included males diagnosed with alcohol dependence (N = 25) and a group of healthy individuals (N = 23). Simultaneous EEG-MEG (electroencephalographic and magnetoencephalographic) activity was recorded in 5 min of eyes-closed resting state. EEG-MEG activity was preprocessed and FC was computed through the leakage-corrected version of phase locking value (ciPLV). Additionally, local (degree, efficiency, clustering) and global (efficiency, characteristic path length) network parameters were computed. Connectivity analysis showed an increase in phase-lagged synchronization, mainly between frontal and frontotemporal regions, in high beta band, and a decrease in interhemispheric gamma, for alcohol-dependent individuals. Network analysis revealed intergroup differences at the local level for high beta, indicating higher degree, clustering, and efficiency, mostly at frontal nodes, together with a decrease in these measures at more posterior sites for patients’ group. The hyper-synchronization in beta, next to the hypo-synchronization in gamma, could indicate an alteration in communication between hemispheres, but also a possible functional compensation mechanism in neural circuits. This could be also supported by network characteristic data, where local alterations in communication are observed. 相似文献
33.
Biological implications of tumor cells in blood and bone marrow of pancreatic cancer patients 总被引:11,自引:0,他引:11
Z'graggen K Centeno BA Fernandez-del Castillo C Jimenez RE Werner J Warshaw AL 《Surgery》2001,129(5):537-546
BACKGROUND: Patients with pancreatic cancer often have tumor recurrence despite curative resection. Cancer cells detected in blood or bone marrow at the time of diagnosis may relate to tumor stage and to prognosis. Recent research emphasis has centered on tumor cells in bone marrow aspirates, but whether these represent early micrometastases or blood-borne cells in transit is unknown. PATIENTS AND METHODS: We developed a specific immunocytochemical assay that evaluated more than 5.3 x 10(6) extracted mononuclear cells per sample of blood and bone marrow and that could identify a single tumor cell in that population. The assay was applied to samples of blood and bone marrow from 105 patients with pancreatic cancer and 66 controls. The prevalence of isolated tumor cells was compared with Union Internationale Contre le Cancer (UICC) stage. A multivariate Cox regression analysis for survival was performed. RESULTS: Pancreatic cancer cells were detected in 26% of blood samples and in 24% of bone marrow specimens. Specificity for cancer was 96%. The prevalence of isolated tumor cells in patients with proven resectable cancer was 9% in blood and 13% in bone marrow. The prevalence increased with UICC tumor stage in blood (P =.04) but not in bone marrow (P =.52) and correlated in blood with resectability (P =.02), progression of disease (P=.08), and peritoneal dissemination (P =.003). While survival correlated significantly with tumor stage (P <.001) and isolated tumor cells in blood correlated with tumor stage, the finding of cancer cells in blood or bone marrow, or both, was not independently associated with survival in patients with pancreatic cancer. CONCLUSIONS: Isolated tumor cells in blood but not bone marrow reflect the stage of growth and spread of pancreatic cancer, particularly in the peritoneal cavity. The findings are consistent with cells in bone marrow aspirates being in transit, not implanted. These disseminated cancer cells may be the consequence, rather than the cause, of progression. 相似文献
34.
Prevalence of Candida spp., xerostomia,and hyposalivation in oral lichen planus – A controlled study
Objective
To determine the frequency of Candida spp., xerostomia, and salivary flow rate (SFR) in three different groups: patients with OLP (OLP group), patients with oral mucosal lesions other than OLP (non‐OLP group), and subjects without oral mucosal lesions (control group).Material and methods
Xerostomia as well as SFR was investigated in the three groups. Samples for isolation of Candida spp. were collected from OLP lesions (38 patients), non‐OLP lesions (28 patients), and healthy subjects (32 subjects).Results
There was no statistically significant difference regarding the frequency of xerostomia and hyposalivation among the three groups (P > 0.05). A higher prevalence for colonization by Candida spp. was found in the healthy subject as compared to that of patients with OLP (P = 0.03) and non‐OLP (P = 0.02) groups. Low SFR was not a factor for colonization by Candida spp.Conclusions
Xerostomia and hyposalivation occur with similar frequency in subjects with and without oral lesions; also, the presence of oral lesions does not increase the susceptibility to colonization by Candida spp. It seems that any study implicating Candida spp. in the malignant transformation of oral lesions should be carried out mostly on a biochemical basis, that is, by testing the capability of Candida spp. to produce carcinogenic enzyme. 相似文献35.
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37.
Peng S Huang J Sheehy JE Laza RC Visperas RM Zhong X Centeno GS Khush GS Cassman KG 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(27):9971-9975
The impact of projected global warming on crop yields has been evaluated by indirect methods using simulation models. Direct studies on the effects of observed climate change on crop growth and yield could provide more accurate information for assessing the impact of climate change on crop production. We analyzed weather data at the International Rice Research Institute Farm from 1979 to 2003 to examine temperature trends and the relationship between rice yield and temperature by using data from irrigated field experiments conducted at the International Rice Research Institute Farm from 1992 to 2003. Here we report that annual mean maximum and minimum temperatures have increased by 0.35 degrees C and 1.13 degrees C, respectively, for the period 1979-2003 and a close linkage between rice grain yield and mean minimum temperature during the dry cropping season (January to April). Grain yield declined by 10% for each 1 degrees C increase in growing-season minimum temperature in the dry season, whereas the effect of maximum temperature on crop yield was insignificant. This report provides a direct evidence of decreased rice yields from increased nighttime temperature associated with global warming. 相似文献
38.
Chronic myelocytic leukemia (CML) may display a lymphoproliferative phase (lymphoid blast crisis) that is generally of B cell phenotype. Since lymphoproliferative disorders may occur following bone marrow transplantation (BMT), it may be difficult to distinguish posttransplant relapse of CML lymphoid blast crisis from de novo lymphoproliferation. Lymphoid blast crisis cells from a patient with CML displayed immunoglobulin heavy chain gene (C mu) rearrangement before BMT. Following BMT the patient developed a lymphoproliferative disorder involving multiple organs. Clonal rearrangement of C mu was demonstrated in several involved tissues. The rearranged C mu restriction fragment was distinct from that displayed before BMT. Additionally, rearrangement of the breakpoint cluster region (bcr) was demonstrated in the pretransplant blast crisis sample, but not in the posttransplant lymphoproliferation samples, thus confirming that these lymphoproliferative disorders were distinct. Molecular genetic techniques offer powerful diagnostic tools for monitoring the course of patients with CML undergoing BMT. 相似文献
39.
BACKGROUND: Polyethylene glycol (PEG) has been shown to potentiate antigen-antibody reactions. STUDY DESIGN AND METHODS: To investigate the utility of PEG in pretransfusion testing, a blinded comparison study of PEG and a low-ionic-strength additive solution (LISS) was conducted. A total of 500 patient samples were tested in parallel with reagent antibody-detection cells using blind-coded PEG and LISS potentiators. RESULTS: In 34 (34%) of 100 samples with known antibodies in the Rh, Kell, Duffy, Kidd, and MNS systems, PEG antiglobulin reactions were stronger (total score, 382) than LISS antiglobulin reactions (total score, 216), and in 66 cases (66%), they were equal to those of LISS. Of 400 samples without detectable antibodies, 384 were negative with PEG and LISS, and 16 were positive in PEG tests and negative in LISS. Seven of the 16 were clinically important antibodies (D, 1; E, 3; Fya, 1; Jka; 1; Jkb, 1), and four were clinically benign antibodies (Le(a), 2; McCc, 1; Sda, 1). Five of the 16 demonstrated inconclusive PEG reactions, for a false-positive rate of 5 in 400 (1.3%). Of the 500 samples, none was negative in PEG tests and positive in LISS (0% false-negative rate). CONCLUSION: Although PEG demonstrates a relatively high false-positive rate, PEG is more sensitive than LISS in detecting clinically significant antibodies. 相似文献
40.
Corticotropin-releasing hormone (CRH) gene and protein expression were examined in the paraventricular nucleus (PVN) of ovariectomized female macaques treated with placebo or hormone therapy (HT) consisting of either estrogen (E) for 28 days, or progesterone (P) for the last 14 of 28 days, or E for 28 days supplemented with P for the last 14 of 28 days using Silastic capsules implanted s.c. in the periscapular region (n=4/group). Perfusion fixed sections (25 microm) at five levels of the PVN (rostral to caudal at 250 microm intervals) were immunostained (ICC) with an antibody to human CRH or processed in an in situ hybridization (ISH) assay with a monkey specific CRH riboprobe. The immunostained CRH-positive area was quantified with a Marianas Stereology Workstation and Slidebook 4.2. There was a significant decrease in the immunological CRH signal with E, P, and E+P treatment as measured by total or average pixels and microns (analysis of variance (ANOVA), p<0.002; Student-Newman-Keul's post hoc test versus placebo control group, p<0.05). There was also a decrease in the number of detectable CRH neurons (ANOVA, p<0.03) with HT. The sections processed for ISH were exposed to autoradiographic films. The CRH mRNA signal was analyzed with NIH Image. The average optical density and positive pixel area of the CRH mRNA signal was significantly suppressed by ovarian HT (ANOVA p<0.002; Student-Newman-Keul's post hoc test versus placebo control group, p<0.05). In summary, 1 month of stable treatment with a moderate dose of E, P or E+P significantly reduced CRH mRNA and protein in the PVN of ovariectomized monkeys. These results suggest that this hormone treatment regimen may increase stress resilience in surgically menopausal primates. 相似文献