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41.
Abstract:  Reflux esophagitis (RE), a major gastrointestinal disorder results from excess exposure of the esophageal mucosa to acidic gastric juice or bile-containing duodenal contents refluxed via an incompetent lower esophageal sphincter. Recent studies implicated oxygen derived free radicals in RE induced esophageal mucosal damage resulting in mucosal inflammation. Thus, control over free radical generation and modulation of inflammatory responses might offer better therapeutic effects to counteract the severity of RE. In this context we investigated the effect of melatonin against experimental RE in rats. Melatonin pretreatment significantly reduced the haemorrhagic lesions and decreased esophageal lipid peroxidation aggravated by RE. Moreover, the depleted levels of superoxide dismutase and glutathione observed in RE were replenished by melatonin signifying its free radical scavenging properties and antioxidant effects resulting in the improvement of esophageal defense mechanism. Further melatonin repressed the upregulated levels of expression of proinflammatory cytokines like, TNF-α, IL-1β and IL-6 in RE. However, increased levels of the anti-inflammatory cytokine IL-10 remained unaltered after melatonin administration signifying its immunomodulatory effect through suppression of Th1-mediated immune responses. The involvement of receptor dependent actions of melatonin against RE were also investigated with MT2 receptor antagonist, luzindole (LUZ). LUZ failed to antagonize melatonin's protective effects against RE indicating that melatonin mediated these beneficial effects in a receptor-independent fashion. Thus, esophageal mucosal protection elicited by melatonin against experimental RE is not only dependent on its free radical scavenging activity but also mediated in part through its effect on the associated inflammatory events in a receptor-independent manner.  相似文献   
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Nasopharyngeal angiofibromas are notorious for silently extending to the regions adjoining their original sites. Their exact localization is essential for the total excision. Conventional X-rays have limited value in demonstrating extensions to base of skull, pterygopalatine fossa and paranasal sinuses. GAT Scanning when used along with contrast, provides clear delineation of every minute tumour extension, along with exact evidence of bone destruction. Angiography on the other hand is additionally useful in determining the vascular feeders, and differentiating from other regional tumefactions. Angiography may further clarify the vascularity and maturity of the tumours. The tumour blush in arterial phase suggests exact localisation of the lesion. Poor filling veins in venous phase indicate larger sinusoidal spaces. Mature or more fibrous tumours have better venous filling during this phase. These three modalities, therefore, appear to be complementary aids to the diagnosis and localisation of tumours and hence essential for planning the surgical procedure for total excision of these nasopharyngeal angiofibromas.  相似文献   
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The ethanolic extract of Syzygium cumini bark has been reported to possess anti-inflammatory activity in our previous studies. The present study is an attempt to elucidate the anti-inflammatory activity of S. Cumini bark against inflammation induced by individual autacoid insult. Histamine (1 mg/ml), 5-HT (1 mg/ml), bradykinin (0.02 mg/ml) and PGE2 (0.001 mg/ml) were used as inflammogens. One of these agents (0.1 ml) was injected s.c. into the right hind paw of each rat. The ethanolic extract of S. cumini bark was tested at the doses of 100, 300 and 1000 mg/kg, p.o. The results indicated the anti-inflammatory activity of S. cumini bark in histamine, 5-HT and PGE2-induced rat paw oedema. However, there was no such significant inhibition of oedema volume observed in bradykinin-induced rat paw oedema at any dose level. Thus, it is concluded that S. cumini exhibits inhibitory role on inflammatory response to histamine, 5-HT and PGE2.  相似文献   
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Experiments with the GW-39 human colonic carcinoma growing in hamsters showed that injection of radioactive antibody to a colorectal-specific, tumor-associated antigen, CSAp, results in better tumor radiolocalization than was seen previously with radioantibodies to carcinoembryonic antigen (CEA). However, a mixture of both radioactive antibodies resulted in potentiation of CEA-tumor radioimmunodetection without affecting CSAp-tumor radiolocalization. Hence, multi-marker antibody mixtures may be the method of choice in cancer radioimmunodetection.  相似文献   
48.
Five cases of xeroderma pigmentosum have been presented, three of the patients belonging to one family. There was no history of consanguineous marriages in this series. All five patients had advanced ocular complications. Three presented with multiple basal cell carcinomata, which were treated by radiotherapy in two cases and surgery in one. One patient presented with a dermatofibroma, which does not seem to have been reported earlier in association with this disease. Reconstructive techniques such as the use of flaps and grafts arc safe, and the healing response is quite satisfactory.  相似文献   
49.
OBJECTIVE: The purpose of this study was to evaluate the efficacy of radiotherapy and concurrent mitomycin-C (MC) plus 5-fluorouracil (5FU) infusion in locally advanced squamous cell carcinoma of the head and neck (SCCHN). METHODS: Sixty-nine patients with SCCHN (6 Stage III and 63 Stage IV patients) were treated with external beam radiotherapy (70 Gy) and simultaneous intravenous chemotherapy with 5FU (600 mg/m(2)/day, Days 1-5) and MC (10 mg/m(2), Days 5 and 36). RESULTS: After a mean follow-up of 28.5 months, 59.4% of patients were alive without disease. Complete response was seen in 76.8% of patients. The 3 years overall survival, locoregional relapse-free survival and disease-free survival was 62.3, 63.1[corrected] and 49.5%, respectively. Treatment was well tolerated (Grade III mucositis in 43.5% and Grade II leukopenia in 5.8%). CONCLUSIONS: This concurrent chemoradiotherapy regimen offers a curative option for our patients where primary and nodal disease is fairly large resulting in hypoxic radioresistant tumors.  相似文献   
50.
Pant R  Yasko AW  Lewis VO  Raymond K  Lin PP 《Cancer》2005,104(1):149-158
BACKGROUND: Chondrosarcoma is the second most common primary sarcoma of bone. It often develops within flat bones, such as the pelvis, ribs, and scapula. In the current study, the authors reviewed the surgical experience and long-term oncologic outcomes of patients with chondrosarcoma arising in the scapula. METHODS: The medical records of 29 consecutive patients with chondrosarcoma of the scapula were reviewed. The patients were treated between 1954 and 1994. All patients had localized disease at the time of presentation. The tumors were classified histologically as Grade 1 (10 patients), Grade 2 (10 patients), Grade 3 (7 patients), dedifferentiated (1 patient), and mesenchymal (1 patient) (using the criteria of Evans et al.). The mean maximal dimension of the tumors was 11 cm. Twenty-five patients underwent limb-sparing surgical resection and 4 patients underwent forequarter amputations. The median follow-up was 13 years (range, 1-35 years). RESULTS: At last follow-up, 22 patients (76%) were free of disease and 7 patients (24%) had died of their disease. Local recurrence occurred in 4 patients at 7 months, 16 months, 40 months, and 43 months, respectively. The local recurrence-free survival rate was 86% at 5 years, 10 years, and 20 years. Disease-specific survival was 83% at 5 years, 74% at 10 years, and 74% at 20 years. Patients who had low-grade chondrosarcomas had better survival compared with patients who had high-grade chondrosarcomas (P = 0.07). CONCLUSIONS: Patients who had localized chondrosarcoma of the scapula had a favorable long-term outcome, most likely due to the unique anatomic features that improved the likelihood of achieving wide surgical margins with limb-sparing surgery, despite the frequent presentation of locally advanced disease.  相似文献   
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