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101.
102.
PURPOSE: Penetration of drug from the anterior chamber to the vitreous is substantial in aphakic eyes, but negligible in normal phakic eyes. The purpose of this study is to investigate the effect of the presence of peripheral iridectomy (PI) which bypasses iris-lens diaphragm on the drug penetration from the anterior chamber to the vitreous. METHODS: Twelve Japanese White rabbits underwent PI in a randomly chosen eye and the same procedures except removal of the peripheral iris in the contralateral eye. Nine weeks after the procedure, topical instillation of 20 microl of 1% nipradilol into the both eyes was repeated three times at five-minute intervals, and two hours later the animals were sacrificed and the both eyes were enucleated. Concentrations of nipradilol in the aqueous and vitreous were determined using a high-performance liquid chromatography. RESULTS: The concentrations of nipradilol were significantly greater in the eyes with PI than those in the contralateral control eyes in the aqueous (5636 +/- 1688 vs 2835 +/- 663 ng/g, mean +/- standard error, n = 12, p = 0.0028) and in the anterior vitreous (11.9 +/- 2.5 vs 5.6 +/- 1.0 ng/g, p = 0.0047), while not in the posterior vitreous or in the posterior retina-choroid. The ratios of the nipradilol concentrations in the anterior or posterior vitreous to that in the aqueous were not significantly different between the both eyes. CONCLUSIONS: The presence of PI had little effect on the penetration of topically instilled nipradilol from the anterior chamber to vitreous. 相似文献
103.
Ito C Itoigawa M Kojima N Tan HT Takayasu J Tokuda H Nishino H Furukawa H 《Planta medica》2004,70(6):585-588
A study of the chemical constituents of the stems of Derris trifoliata Lour. (Leguminosae) led to the isolation and identification of one new rotenoid, 6aalpha,12aalpha-12a-hydroxyelliptone ( 3), together with five other known rotenoids. In a search for novel cancer chemopreventive agents (anti-tumor promoters), we carried out a primary screening of five of the rotenoids isolated from the plant for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12- O-tetradecanoylphorbol 13-acetate (TPA) in Raji cells. The inhibitory activity of 3 was found to be equivalent to that of beta-carotene without any cytotoxicity. Deguelin ( 4) and alpha-toxicarol ( 5) exhibited a marked inhibitory effect on mouse skin tumor promotion in an in vivo two-stage carcinogenesis test. This investigation indicated that rotenoids might be valuable anti-tumor promoters. 相似文献
104.
Ito C Itoigawa M Kojima N Tan HT Takayasu J Tokuda H Nishino H Furukawa H 《Planta medica》2004,70(1):8-11
A study of the chemical constituents of the stems of Derris trifoliata Lour. (Leguminosae) led to the isolation and identification of one new rotenoid, 6aalpha,12aalpha-12a-hydroxyelliptone ( 3), together with five other known rotenoids. In a search for novel cancer chemopreventive agents (anti-tumor promoters), we carried out a primary screening of five of the rotenoids isolated from the plant for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by 12- O-tetradecanoylphorbol 13-acetate (TPA) in Raji cells. The inhibitory activity of 3 was found to be equivalent to that of beta-carotene without any cytotoxicity. Deguelin ( 4) and alpha-toxicarol ( 5) exhibited a marked inhibitory effect on mouse skin tumor promotion in an in vivo two-stage carcinogenesis test. This investigation indicated that rotenoids might be valuable anti-tumor promoters. 相似文献
105.
Takitani K Inoue A Koh M Kawakami C Kuno T Kawamura N Miyake M Tamai H 《Journal of nutritional science and vitaminology》2004,50(3):219-221
All-trans retinoic acid (ATRA) is used as differentiation therapy for acute promyelocytic leukemia (APL). The two major adverse effects of ATRA therapy are hyperleukocytosis and retinoic acid syndrome. In order to prevent these adverse effects, low-dose ATRA therapy (25 mg/m2/d) has been tried in adults. Accordingly we assessed the pharmacokinetics of low-dose ATRA in children with cancer. Four children (one with APL and three with other advanced cancer) were administered ATRA and its pharmacokinetics were evaluated. In three patients, the pharmacokinetic parameters of ATRA were similar to those previously determined for APL patients in remission, but the values were lower in one patient. Low-dose ATRA was effective for APL, but not for the solid tumors. This therapy did not cause any severe toxicity. Further studies are needed to determine the optimum ATRA regimen and to evaluate low-dose ATRA combined with chemotherapy in children with APL. 相似文献
106.
Kuwahara C Imamura Y Okamura N Sakai R Ikeda T 《American journal of ophthalmology》2003,135(5):722-723
PURPOSE: To report a patient with Takayasu disease with severe proliferative retinopathy progressing to bilateral blindness. A 57-year-old Japanese woman suffering from Takayasu disease for 16 years manifested severe proliferative retinopathy in both eyes, leading to blindness due to optic atrophy. DESIGN: Interventional case report. METHODS: A 57-year-old Japanese woman suffering from Takayasu disease for 16 years underwent a comprehensive opthalmologic examination. Panretinal photocoagulation and vitrectomy were performed on both eyes. SETTINGS: Institutional practice. RESULTS: At initial examination, the patient was found to have severe proliferative retinopathy with tractional retinal detachment in both eyes. The retinal detachments were repaired by the vitrectomy, however, the patient developed bilateral blindness due to optic atrophy. CONCLUSIONS: Patients with a long history of Takayasu disease can demonstrate severe proliferative retinopathy that may be resistant to photocoagulation and/or vitreous surgery. Ocular ischemia can lead to blindness from ischemic optic neuropathy. 相似文献
107.
Evaluation of oxidative stress during apoptosis and necrosis caused by D-galactosamine in rat liver 总被引:5,自引:0,他引:5
Sun F Hamagawa E Tsutsui C Sakaguchi N Kakuta Y Tokumaru S Kojo S 《Biochemical pharmacology》2003,65(1):101-107
Eighteen and twenty-four hours after intraperitoneal administration of D-galactosamine (1g/kg body weight) to rats, the activity of caspase-3-like protease in the liver increased significantly compared with that in the control group given saline. Histological examinations including the in situ terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) method found apoptotic hepatocytes 18 hr after the administration of D-galactosamine. Caspase-3 activity was barely detectable in the plasma of control rats, but increased significantly 24 hr after drug administration along with a dramatic increase in glutamate-oxaloacetate transaminase (GOT). These results indicated that D-galactosamine causes apoptosis in the liver by activating caspase-3, which is released to the plasma by secondary necrosis. The concentration of lipid hydroperoxides in the liver increased significantly 24 hr after D-galactosamine administration. In contrast, the concentration of vitamin C in the liver decreased significantly 18 and 24 hr after D-galactosamine administration. These results suggest that D-galactosamine induces severe oxidative stress in the liver, leading to extensive necrosis. 相似文献
108.
Accuracy and reproducibility of manual and semiautomated quantification of MS lesions by MRI 总被引:4,自引:0,他引:4
Ashton EA Takahashi C Berg MJ Goodman A Totterman S Ekholm S 《Journal of magnetic resonance imaging : JMRI》2003,17(3):300-308
PURPOSE: To evaluate the accuracy, reproducibility, and speed of two semiautomated methods for quantifying total white matter lesion burden in multiple sclerosis (MS) patients with respect to manual tracing and to other methods presented in recent literature. MATERIALS AND METHODS: Two methods involving the use of MRI for semiautomated quantification of total lesion burden in MS patients were examined. The first method, geometrically constrained region growth (GEORG), requires user specification of lesion location. The second technique, directed multispectral segmentation (DMSS), requires only the location of a single exemplar lesion. Test data sets included both clinical MS data and MS brain phantoms. RESULTS: The mean processing times were 60 minutes for manual tracing, 10 minutes for region growth, and 3 minutes for directed segmentation. Intra- and interoperator coefficients of variation (CVs) were 5.1% and 16.5% for manual tracing, 1.4% and 2.3% for region growth, and 1.5% and 5.2% for directed segmentation. The average deviations from manual tracing were 9% for region growth and 5.7% for directed segmentation. CONCLUSION: Both semiautomated methods were shown to have a significant advantage over manual tracing in terms of speed and precision. The accuracy of both methods was acceptable, given the high variability of the manual results. 相似文献
109.
Ochiai N Shimazaki C Uchida R Fuchida S Okano A Ashihara E Inaba T Fujita N Nakagawa M 《Leukemia & lymphoma》2003,44(2):369-372
A 62-year-old man diagnosed with acute myelogenous leukemia which had developed from myelodysplastic syndrome received cytarabine and idarubicine as an induction therapy. The patient developed pneumonia and bacterial sepsis during profound neutropenia. Fever and sepsis improved by using many anti-bacterials and anti-fungals but he became febrile again and complained of severe lumbar pain. 67Ga scintigram showed abnormal uptake in the lumbar vertebra and left sternoclavicular joint, suggesting a diagnosis of discitis and osteomyelitis in the lumbar vertebra and sternoclavicular arthritis. We biopsied the site several times but culture of the biopsy specimen could not isolate any pathogens, and high fever persisted for about 10 months despite administration of various anti-bacterials and anti-fungals. Finally we inserted a catheter into the abscess at the iliopsoas muscle and Scedosporium apiospermum was isolated in the bloody pus obtained from the catheter. Itraconazole and amphotericin B were restarted, and the high fever and lumbar pain improved rapidly. The findings of S. apiospermum infection in this patient emphasizes the importance of being aware of this pathogen in patients with hematologic malignancy during the neutropenic phase. 相似文献
110.
We report herein the case of a 77-year-old woman found to have mixed medullary-papillary carcinoma in the right thyroid with lymph node metastases 30 years after a left thyroidectomy. The preoperative values of serum calcitonin and carcinoembryonic antigen (CEA) were high, and fine-needle aspiration biopsy revealed class V, which led us to suspect papillary carcinoma. A right thyroidectomy with dissection of the right neck lymph nodes was performed. Histopathological examination of the tumor specimens revealed gradual borders between medullary carcinoma and papillary carcinoma with positive immunohistochemical staining to calcitonin, chromogranin A, CEA, and thyroglobulin. The serum levels of calcitonin and CEA decreased to normal after the operation. The point mutation of the RET proto-oncogene was found to be negative by a DNA analysis of the peripheral leukocytes. This cancer seemed not to be associated with multiple endocrine neoplasia type 2 syndrome. The presence of both medullary and papillary components in the thyroid with lymph node metastases is rare and may suggest that the tumor had arisen from a common stem cell. 相似文献