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81.
Surgical excision is the treatment of choice for lipomas. However, linear incision methods or minimal extraction techniques often do not provide a sufficient surgical view. Therefore, removing large lipomas is often difficult. To present the Z‐incision and half Z‐incision designs for lipoma extraction, this retrospective study analyzed lipomas surgically excised at our institution between September 2015 and December 2018. The area of surgical field exposed by the Z‐incision versus that exposed by the linear incision was calculated using a schematic model. Cure rate, complications, and surgical field area were investigated. A total of 84 lipomas were included. A Z‐ or half Z‐incision was used to treat 30 lipomas, while a linear incision was used to treat 54 lipomas. The mean diameter of the mass in the Z‐ or half Z‐incision group was 47.7 mm (range, 15–160 mm), larger than that in the linear incision group (25.5 mm; range, 7–59 mm) (p < .001). The Z‐incision involved making rectangular windows by lifting 2 triangular flaps. According to our mathematical model, the Z‐incision provided a larger surgical field area than that provided by the linear incision based on stretched angles (1.81 times larger at 30° and 3.14 times larger at 15°). The Z‐ and half Z‐incisions were successfully performed in all but 1 lipoma (29 lipomas, 96.7%). There was 1 lipoma that resulted in postoperative complications (seroma, 3.3%). The Z‐incision design can be a useful alternative technique for the extirpation of lipomas, especially large lipomas. Here, we proposed a surgical algorithm for lipoma surgery based on tumor size.  相似文献   
82.
Animal models of human diseases are crucial experimental tools to investigate the mechanisms involved in disease pathogenesis and to develop new therapies. In spite of the numerous animal models currently available that reproduce several neuropathological features of Parkinson disease (PD), it is challenging to have one that consistently recapitulates human PD conditions in both motor behaviors and biochemical pathological outcomes. Given that, we have implemented a new paradigm to expose rats to a chronic low dose of paraquat (PQ), using osmotic minipumps and characterized the developed pathologic features over time. The PQ exposure paradigm used lead to a rodent model of PD depicting progressive nigrostriatal dopaminergic neurodegeneration, characterized by a 41% significant loss of dopaminergic neuron in the substantia nigra pars compacta (SNpc), a significant decrease of 18% and 40% of dopamine levels in striatum at week 5 and 8, respectively, and a significant 1.5‐fold decrease in motor performance. We observed a significant increase of microglia activation state, sustained levels of α‐synucleinopathy and increased oxidative stress markers in the SNpc. In summary, this is an explorative study that allowed to characterize an improved PQ‐based rat model that recapitulates cardinal features of PD and may represent an attractive tool to investigate several mechanisms underlying the various aspects of PD pathogenesis as well as for the validation of the efficacy of new therapeutic approaches that targets different mechanisms involved in PD neurodegeneration.  相似文献   
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84.
CKD-516 (Valecobulin), a vascular-disrupting agent, inhibits microtubule elongation. We evaluated the effect of CKD-516 on lung cancer cells and the underlying molecular mechanisms. The effects of S516, an active metabolite of CKD-516, were evaluated in HUVECs and three lung cancer cell lines and by a microtubule polymerization assay. Tubulin cross-linking was used to identify the binding site of S516 on tubulin, and Western blotting was performed to identify the intracellular pathways leading to cell death. Subcutaneous lung cancer xenograft models were used to assess the in vivo effect of CKD-516 on tumor growth. S516 targeted the colchicine binding site on β-tubulin. In lung cancer cells, S516 increased endoplasmic reticulum (ER) stress and induced reactive oxygen species (ROS) generation by mitochondria and the ER. In addition, CKD-516 monotherapy strongly inhibited the growth of lung cancer xenograft tumors and exerted a synergistic effect with carboplatin. The findings suggest that CKD-516 exerts an anticancer effect in company with inducing ER stress and ROS production via microtubule disruption in lung cancer cells. CKD-516 may thus have therapeutic potential for lung cancer.  相似文献   
85.
Several studies have suggested the possibility of a prognostic relationship between Epstein–Barr virus (EBV) and diffuse large B‐cell lymphoma (DLBCL). The clinical outcome of EBV‐associated DLBCL is not clear, especially since the introduction of rituximab. We retrospectively analyzed 222 elderly patients (≥50 years) with DLBCL who received R‐CHOP chemotherapy and evaluated the state of EBV‐encoded RNA‐1 (EBER). Eighteen cases (8.1%) were EBER‐positive (+). After a median of six cycles of R‐CHOP chemotherapy, the response rate (≥partial response) was 72.2% (13/18) in the EBV (+) patients and 90.2% (184/204) in the EBV (?) DLBCL patients (P = 0.021). Four of 18 (22.2%) EBV (+) DLBCL patients received two or fewer cycles of R‐CHOP chemotherapy. R‐CHOP chemotherapy was also interrupted early more frequently compared with the EBV (?) group (2.5%) (P = 0.00). At a median follow‐up of 32.8 months, there was no significant difference in the overall survival between the groups (P = 0.627). The EBV (+) DLBCL patients with early interruption of R‐CHOP chemotherapy showed a trend toward a high EBV‐DNA titer (≥1,000 copies/mL) (P = 0.091). The results suggest that the EBV (+) tumoral status of elderly DLBCL patients who undergo R‐CHOP chemotherapy does not predict their survival but that their EBV status may contribute to the early interruption of R‐CHOP chemotherapy. Am. J. Hematol. 88:774–779, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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87.
The aim of this study was to detect the amount of lactic acid (LA) and glycolic acid (GA) in poly(D,L-lactide-co-glycolide) (PLGA) by development a simple HPLC method and to determine the pH of media, which can influence on degradation of PLGA and drug release. Analysis of in vitro degradation behavior of PLGA with two different molecular weights as 8000 and 33,000 g/mol were performed in various media conditions (pH 3.0, 5.0, 7.0, and 9.0 of PBS and distilled water (approx. pH 5.8)). Also, effect of some additives on PLGA degradation was also investigated in pH 7.0 of PBS. GA and LA were easily detected by a simple HPLC method (retention time: 6.5 min and 10.2 min, respectively). The result showed that GA was released larger amount than that of LA considering the initial sample weight of polymers, due to the higher hydrophilic property. In the lower pH of media conditions, the PLGA was faster degraded generally. The presence of various additives, moreover, affected decrease of pH and slight acceleration of LA and GA detection.  相似文献   
88.
The objective of this study is to describe the clinical outcomes of patients treated for cervical pregnancy with or without methotrexate (MTX) and to evaluate the effects of MTX in the treatment of cervical pregnancy. Between January 1993 and February 2000, 31 patients were diagnosed with cervical pregnancy. Twenty-two patients were treated with MTX chemotherapy and nine patients were treated with surgical procedures without MTX treatment. In the non-MTX treatment group, three patients underwent total abdominal hysterectomy, five required adjuvant procedures to control the bleeding during dilatation and curettage (D&C) and only one patient was treated with a simple D&C. In the MTX treatment group, fourteen (63.6%) patients were treated with only MTX and eight (36.4%) cases underwent concomitant procedures (simple curettage, curettage and Foley catheter tamponade, cervical cerclage, ligation of the descending branches of uterine arteries, or ligation of hypogastric arteries). The uterus was preserved in all cases and three women delivered healthy babies in their subsequent pregnancy. In conclusion, early diagnosis, appropriate MTX regimen in combination of necessary adjuvant conservative procedures could contribute to successful treatment with preservation of the uterus and future reproductive ability.  相似文献   
89.
It was reported previously that ESP‐102, a combined extract of Angelica gigas, Saururus chinensis and Schizandra chinensis, significantly improved scopolamine‐induced memory impairment in mice and protected primary cultured rat cortical cells against glutamate‐induced toxicity. To corroborate this effect, the action patterns of ESP‐102 were elucidated using the same in vitro system. ESP‐102 decreased the cellular calcium concentration increased by glutamate, and inhibited the subsequent overproduction of cellular nitric oxide and reactive oxygen species to the level of control cells. It also preserved cellular activities of antioxidative enzymes such as superoxide dismutase, glutathione peroxidase and glutathione reductase reduced in the glutamate‐injured neuronal cells. While a loss of mitochondrial membrane potential was observed in glutamate treated cells, the mitochondrial membrane potential was maintained by ESP‐102. These results support that the actual mechanism of neuroprotective activity of ESP‐102 against glutamate‐induced oxidative stress might be its antioxidative activity. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
90.
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