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991.
Pfaffia paniculata (Brazilian ginseng) roots have been indicated for the treatment of several diseases. Our studies have shown that P. paniculata roots present antineoplastic effects and cancer chemopreventive activity in a mouse hepatocarcinogenesis model. The purpose of this study was to investigate the effects of the Brazilian ginseng on corneal angiogenesis in mice. We first conducted a toxicological study employing 250, 500, or 1000 mg/kg/day of the methanolic extract of P. paniculata roots by gavage to BALB/c mice. Animals did not lose weight during the treatment nor presented histopathological alterations. The effect of this root on angiogenesis in the cornea of BALB/c mice was then assessed. Male mice were treated, by gavage, once a day, with doses of 250, 500, or 1000 mg/kg of methanolic extract of P. paniculata powdered root for 10 days; filtered water was used as control. Corneal cauterization was accomplished by the contact of a silver nitrate crystal on the central area of the cornea, in the 5th day of treatment with P. paniculata, which continued thereafter; the animals were euthanized on the 6th day after cauterization. Newly formed blood vessels were filled with India ink, and the corneas were routinely processed. Blood vessels were quantified in an image analysis system. A smaller total area of neovascularization in the mouse cornea was observed in animals treated with 1000 mg/kg of the methanolic extract of P. paniculata. These results indicate an antiangiogenic effect of this extract. The mechanisms of this antiangiogenic activity of P. paniculata should be further investigated.  相似文献   
992.
The previous studies from our laboratory reported that benzo(a)pyrene (Bap) influenced efflux transport of rhodamine 123 (Rho-123) by induction of P-glycoprotein (P-gp) in Caco-2 cells. The present study investigated whether induction of P-gp and the enhanced efflux transport of Rho-123 were caused by benzo(e)pyrene (Bep), which has a structure similar to Bap, but is not a carcinogenic compound. In Caco-2 monolayer exposed to 50 microM Bep for 72 h, the ratio of the apparent permeability coefficient (P(app)) of Rho-123 efflux increased significantly compared to that of the control monolayer. Similarly, a significant increase in expression of MDR1 mRNA and of P-gp at the protein level were detected by RT-PCR and by Western blot analysis, respectively, in Caco-2 cells exposed to Bep, compared to that of the control. Caco-2 cells exposed to Bep showed oxidative stress that was detected by fluorescence microscopy using aminophenyl fluorescein. However, the oxidative stress was weaker compared with that of Bap. The cellular GSH content was decreased to 80% or 59% of control cells, respectively, in Caco-2 cells exposed to either Bep or Bap. Our results further show that Bep or Bap-induced P-gp in Caco-2 cells might have been the result of oxidative stress rather than DNA damage.  相似文献   
993.
A 79-year-old right-handed woman was admitted to hospital following sudden onset of severe visual loss in the left eye. Left central retinal artery occlusion (CRAO) was diagnosed. Diffusion-weighted imaging showed an asymptomatic hyperintensity in left middle cerebral artery territory. Transcranial Doppler and transesophageal echocardiography revealed patent foramen ovale. No other embolic sources were identified in the carotid artery, aortic arch, or heart. We report herein a case of CRAO caused by paradoxical brain embolism.  相似文献   
994.
A 72-year-old right handed man developed right homonymous hemianopia without macular sparing, left homonymous lower quadranopia with macular sparing, cerebral amblyopia, cerebral achromatopsia, impaired form vision, and mild right hemispatial neglect, after multiple cerebral infarctions, involving bilateral occipital cortices. His intelligence and memory were deteriorated moderately. He failed to notice objects located in the affected visual field, because of his severely impaired visual search. When ordinary lighting was used, he showed severe right-sided omissions on the line cancellation test. However, omissions were less marked under the brighter lighting. By using a modified method of Kerkhoff and Vianen (1994), he was trained to make saccadic eye movements toward affected regions to find a target and to search and point at targets arranged randomly. As the sensitivity for contrast of isoluminante red and green stimuli was preserved well at high spatial frequencies despite the decreaced contrast sensitivity for brightness, we used green targets as the training stimuli. After the training, search field and pointing range that could be covered by the patient increased in size for both green and white targets, and daily activities improved. Moreover, after the training, he no longer showed discrepancy in line cancellation performances between ordinary and brighter lighting conditions. In the follow up period, the search field and the performance on the line cancellation test were maintained, while the performance of pointing targets array declined. The family members complained of mild re-deterioration of daily activities. Then, the training for searching and pointing re-introduced at home. After the training, his pointing performance and daily activities, evaluated by questionnaires to his family members, improved again. In conclusion, it was suggested that disordered visual search after a homonymous field defect can be treated effectively, even if multiple visual dysfunctions were associated.  相似文献   
995.
PURPOSE: High serum carbohydrate antigen 19-9 in patients with hydronephrosis but without malignant disease is reportedly rare but to our knowledge the clinical features of hydronephrosis that affect this level have not yet been clarified. We examined the correlation of serum carbohydrate antigen 19-9 with hydronephrosis status in patients with benign hydronephrosis. MATERIALS AND METHODS: We used 123 serum samples from 68 patients with and 55 without hydronephrosis. All patients enrolled in this study had no malignant disease. Serum carbohydrate antigen 19-9 was measured by immunoradiometric assay and that level was correlated with clinical factors. RESULTS: Serum carbohydrate antigen 19-9 in patients with hydronephrosis was significantly higher than in those without hydronephrosis (p <0.0001). The serum level was elevated to greater than 37 units per ml. in 25% of the patients with but in only 1.8% of those without hydronephrosis. In the hydronephrosis group the clinical features that significantly correlated with the increased serum level were bilateral hydronephrosis, urinary tract infection, proteinuria, increased serum blood urea nitrogen, severe urinary tract occlusion and high grade hydronephrosis. CONCLUSIONS: Serum carbohydrate antigen 19-9 was significantly elevated in patients with benign hydronephrosis. Hydronephrosis causes false-positive results when screening for malignant disease by serum carbohydrate antigen 19-9 measurement.  相似文献   
996.
Forty-five cirrhotic patients with oesophageal varices were randomized to receive endoscopic injection sclerotherapy with either 5% ethanolamine oleate (EO), or 5% sodium morrhuate (SM). In the EO group, there was a statistically significant higher rate of disappearance of red colour signs on the varices a week after the initial session of sclerotherapy than in the SM group (91.3% vs 45.5%, P less than 0.05). A jet-like bleeding from injection sites at the second session of sclerotherapy occurred in three patients in the SM group and they experienced blurred vision. There was no such occurrence in the EO group. Oesophageal bleeding requiring blood transfusion during the course of repeated sclerotherapy occurred only in the SM group (five patients): bleeding was from a partly thrombosed varix and in four was from oesophageal ulcers. We found that EO administered intravariceally is more efficacious than SM for sclerotherapy of oesophageal varices.  相似文献   
997.
Micro-distributions of tetrodotoxin (TTX) in the skin of a brackish-water puffer Tetraodon nigroviridis were investigated by means of a monoclonal anti-TTX antibody under light and transmission electron microscope. In light microscopy TTX antigen was visualized as brown color in undifferentiated basal cells and succiform cells of the skin, while in electron microscopy TTX was detected as black dots of immunogold in lysosomes of basal cells. From the results, it can be inferred that when TTX from the blood plasma of T. nigroviridis enters into the undifferentiated basal cells through diffusion, it is taken to the lysosomes by phagocytosis and exists there through binding with internal constituent(s) of the organelles.  相似文献   
998.
999.
Primary malignant melanoma of the male urethra   总被引:1,自引:0,他引:1  
We report a case of primary malignant melanoma of the male urethra in a patient whose penile shaft was successfully preserved, but who proceeded to acute renal failure (ARF) after interferon (IFN)-beta adjuvant immunotherapy. Primary malignant melanoma of the male urethra is rare and usually shows highly malignant potential. Therefore, urologists must often perform phallectomy, which impacts on the patient both sexually and mentally. A 64-year-old man presented at Saiseikai Sendai Hospital with asymptomatic gross hematuria and was diagnosed as distal urethral tumor. We predicted the highly malignant potential of this tumor from the urethroscopic finding and from urinary cytological examination. We did not select trans-urethral resection (TUR), but selected partial urethrectomy. This patient proceeded to ARF 1 month after natural IFN-beta treatment as an adjuvant immunotherapy. As IFN-beta rarely induces the delayed renal failure, urologists should be aware of renal dysfunction after IFN-beta therapy for the treatment of malignant melanoma.  相似文献   
1000.
A 53-yr-old man with a history of chronic renal failure was admitted to the hospital of Hyogo College of Medicine on March 24th, 1999, because of severe continuous hemoptysis. On February 14th, 1999, the patient had undergone a cadaveric kidney transplantation in the urology department of another hospital. He did not experience any immunological reactions due to tissue rejection. On admission, subcutaneous bleeding at the site of an injection received 1 month before was noticed on his left arm. Petecheae of the extremities and a conjunctival hemorrhage were also noted. However, coagulation and fibrinolysis tests were essentially normal. These findings indicated that the hemorrhages were due to vessel weakness. Scurvy was diagnosed since his serum vitamin C was extremely low (0.2 microgram/ml). The patient was given ascorbic acid (1 g/day), and his condition improved dramatically. Ten years ago, the patient had had renal failure, which had been treated with chronic maintenance dialysis and dietary restriction. It has been postulated that a diet lacking in vitamin C or the steroid treatment he received after kidney transplantation may have induced the scurvy.  相似文献   
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