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71.
Philadelphia chromosome-positive mixed phenotype acute leukemia (Ph+MPAL) is a rare type of acute leukemia having myeloid and lymphoid features. In the present study, we describe the successful treatment of a 71-year-old Japanese female patient with Ph+MPAL by the alternation of second-generation tyrosine kinase inhibitors according to BCR-ABL1 mutations. The patient survived in her third complete remission (CR) for over 4 years. In her first CR, the patient was treated with multiple-agent chemotherapy and underwent maintenance therapy with imatinib and monthly vincristine and prednisolone (VP). At the first relapse, an examination of the bone marrow revealed a transformation into acute lymphoblastic leukemia and an F317L mutation in BCR-ABL1 gene, which responded preferentially to nilotinib over dasatinib. She achieved second CR, and nilotinib with VP therapy was selected for maintenance treatment. At second relapse, BCR-ABL1 mutational analysis revealed Y253H mutation instead of F317L mutation, resulting in resistance to nilotinib. The patient achieved third CR with dasatinib and VP therapy, and maintained CR with this treatment. This suggests that appropriate alternation of TKIs may contribute to long-term survival in elderly patients with Ph+MPAL.  相似文献   
72.
This study aimed (1) at determining the levels of the fungal toxin sterigmatocystin (STC) in the feed and urine of cattle and (2) at evaluating the effects of supplementing the feed with a mycotoxin adsorbent (MA) on STC concentrations in urine. Two herds of female Japanese Black cattle were used in this study. The cattle in each herd were fed a standard ration containing rice straw from different sources and a standard concentrate; two groups of cattle from each herd (n = six per group) received the commercial MA, mixed with the concentrate or given as top-dressing, whereas a third group received no supplement and served as control. Urine and feed samples were collected at various time points throughout the experiment. STC concentrations were measured using liquid chromatography-tandem mass spectrometry (LC-TMS). STC concentrations in straw were higher in Herd 1 (range 0.15–0.24 mg/kg DM) than in Herd 2 (range <0.01–0.06 mg/kg DM). In Herd 1, STC concentrations in urine significantly declined 2 weeks after replacing the contaminated feed, whereas MA supplementation had no effect. In conclusion, mycotoxins in urine samples are useful biological markers for monitoring the systemic exposure of cattle to multiple mycotoxins, as well as evaluating the effectiveness of interventions.  相似文献   
73.
Journal of Muscle Research and Cell Motility - The regulated assembly of actin filaments is essential in nearly all cell types. Studying actin assembly dynamics can pose many technical challenges....  相似文献   
74.
The programmed cell death 1 (PD1)/PD1 ligand (PD-L1) axis plays an important role in tumor cell escape from immune control and has been most extensively investigated for therapeutic purposes. However, PD-L1 immunohistochemistry is still not used widely for diagnosis. We review the diagnostic utility of PD-L1 (by clone SP142) immunohistochemistry in large-cell lymphomas, mainly consisting of classic Hodgkin lymphoma (CHL) and diffuse large B-cell lymphoma (DLBCL). Neoplastic PD-L1 (nPD-L1) expression on Hodgkin and Reed-Sternberg cells is well-established among prototypic CHL. Of note, EBV+ CHL often poses a challenge for differential diagnosis from peripheral T-cell lymphoma with EBV+ non-malignant large B-cells; their distinction is based on the lack of PD-L1 expression on large B-cells in the latter. The nPD-L1 expression further provides a good diagnostic consensus for CHL with primary extranodal disease conceivably characterized by a combined pathogenesis of immune escape of tumor cells and immunodeficiency. Compared with CHL, the nPD-L1 expression rate is much lower in DLBCL, highlighting some specific subgroups of intravascular large B-cell lymphoma, primary mediastinal large B-cell lymphoma, and EBV+ DLBCL. They consist of nPD-L1-positive and -negative subgroups, but their clinicopathological significance remains to be elucidated. Microenvironmental PD-L1 positivity on immune cells may be associated with a favorable prognosis in extranodal DLBCL. PD-L1 (by SP142) immunohistochemistry has helped us to understand the immune biology of lymphoid neoplasms possibly related by immune escape and/or immunodeficiency. However, knowledge of these issues remains limited and should be clarified for diagnostic consensus in the future.  相似文献   
75.
76.
Although smectite-type clays are used as heterogeneous media for photofunctional guest molecules, the guest species are limited to cationic or polar molecules because of the intrinsic negative electric charges of clay particles. Nevertheless, in this study, aqueous clay colloids are reported to affect the photoisomerization kinetics of anionic and cationic azobenzene molecules dissolved in the colloids. Under UV-light irradiation, the clay colloids decelerate trans-to-cis isomerization, while under visible-light irradiation, the clay colloids accelerate cis-to-trans isomerization. In addition, the sol–gel transition of clay colloids affects the kinetics. The results considerably expand the applicability of clay colloids as matrixes for functional organic species.

Aqueous clay colloids influence the photoisomerization kinetics of both of the anionic and cationic azobenzene molecules although the guest species has been limited to cationic or polar molecules because of the intrinsic negative electric charges of the clay particles.  相似文献   
77.
Uremic sarcopenia is a serious clinical problem associated with physical disability and increased morbidity and mortality. Methylglyoxal (MG) is a highly reactive, dicarbonyl uremic toxin that accumulates in the circulatory system in patients with chronic kidney disease (CKD) and is related to the pathology of uremic sarcopenia. The pathophysiology of uremic sarcopenia is multifactorial; however, the details remain unknown. We investigated the mechanisms of MG-induced muscle atrophy using mouse myoblast C2C12 cells, focusing on intracellular metabolism and mitochondrial injury. We found that one of the causative pathological mechanisms of uremic sarcopenia is metabolic flow change to fatty acid synthesis with MG-induced ATP shortage in myoblasts. Evaluation of cell viability revealed that MG showed toxic effects only in myoblast cells, but not in myotube cells. Expression of mRNA or protein analysis revealed that MG induces muscle atrophy, inflammation, fibrosis, and oxidative stress in myoblast cells. Target metabolomics revealed that MG induces metabolic alterations, such as a reduction in tricarboxylic acid cycle metabolites. In addition, MG induces mitochondrial morphological abnormalities in myoblasts. These changes resulted in the reduction of ATP derived from the mitochondria of myoblast cells. Our results indicate that MG is a pathogenic factor in sarcopenia in CKD.  相似文献   
78.
79.
This study addresses an advantageous application of a urinary zearalenone (ZEN) monitoring system not only for surveillance of ZEN exposure at the production site of breeding cows but also for follow-up monitoring after improvement of feeds provided to the herd. As biomarkers of effect, serum levels of the anti-Müllerian hormone (AMH) and serum amyloid A (SAA) concentrations were used. Based on the results of urinary ZEN measurement, two cows from one herd had urinary ZEN concentrations which were two orders of magnitude higher (ZEN: 1.34 mg/kg, sterigmatocystin (STC): 0.08 mg/kg in roughages) than the levels of all cows from three other herds (ZEN: not detected, STC: not detected in roughages). For the follow-up monitoring of the herd with positive ZEN and STC exposure, urine, blood, and roughage samples were collected from five cows monthly for one year. A monitoring series in the breeding cattle herd indicated that feed concentrations were not necessarily reflected in urinary concentrations; urinary monitoring assay by ELISA may be a simple and accurate method that reflects the exposure/absorption of ZEN. Additionally, although the ZEN exposure level appeared not to be critical compared with the Japanese ZEN limitation in dietary feeds, a negative regression trend between the ZEN and AMH concentrations was observed, indicating that only at extremely universal mycotoxin exposure levels, ZEN exposure may affect the number of antral follicles in cattle. A negative regression trend between the ZEN and SAA concentrations could also be demonstrated, possibly indicating the innate immune suppression caused by low-level chronic ZEN exposure. Finally, significant differences (p = 0.0487) in calving intervals between pre-ZEN monitoring (mean ± SEM: 439.0 ± 41.2) and post-ZEN monitoring (349.9 ± 6.9) periods were observed in the monitored five cows. These preliminary results indicate that the urinary ZEN monitoring system may be a useful practical tool not only for detecting contaminated herds under field conditions but also provides an initial look at the effects of long-term chronic ZEN/STC (or other co-existing mycotoxins) exposure on herd productivity and fertility.  相似文献   
80.
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