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991.
目的对自闭症病人给予被动性语言刺激,评价采用功能性磁共振(MR)成像作为判断病人有无语言缺陷的客观指标的可行性。材料与方法本研究为前瞻性研究,研究方 相似文献
992.
Brain abscess and necrotic brain tumor: discrimination with proton MR spectroscopy and diffusion-weighted imaging 总被引:15,自引:0,他引:15
Lai PH Ho JT Chen WL Hsu SS Wang JS Pan HB Yang CF 《AJNR. American journal of neuroradiology》2002,23(8):1369-1377
BACKGROUND AND PURPOSE: Discriminating pyogenic brain abscesses from cystic or necrotic tumors is sometimes difficult with CT or MR imaging. We compared findings of proton MR spectroscopy ((1)H-MRS) with those of diffusion-weighted imaging to determine which technique was more effective for this differential diagnosis. METHODS: Fourteen patients (necrotic or cystic tumor [n = 7]; pyogenic abscess [n = 7]) who underwent 1.5-T (1)H-MRS and diffusion-weighted imaging and had findings of ring-shaped enhancement after contrast agent administration were enrolled in this study. Diffusion-weighted imaging was performed with a single-shot spin-echo echo-planar pulse sequence (b = 1000 s/mm(2)). The apparent diffusion coefficient and ratio were also measured. RESULTS: Spectra for two patients were unacceptable because of either poor shimming conditions or contamination from neighboring fat. Spectra in three of five patients with abscess had lactate, amino acids (including valine, alanine, and leucine), and acetate peaks; one of the three spectra had an additional peak of succinate. In one patient with abscess treated by antibiotics, only lactate and lipid peaks were detected. Spectra for four of seven patients with cystic or necrotic tumors showed only lactate peaks. Lactate and lipids were found in three patients with tumors. Hyperintensity was seen in all the pyogenic abscess cavities and hypointensity in all the cystic and necrotic tumors on diffusion-weighted images. CONCLUSION: (1)H-MRS and diffusion-weighted imaging are useful for differentiating brain abscess from brain tumor, but the latter requires less time and is more accurate than is (1)H-MRS. (1)H-MRS is probably more limited in cases of smaller peripheral lesions, skull base lesions, and treated abscesses. 相似文献
993.
大肠侧向发育型肿瘤细胞株的建立及其鉴定 总被引:9,自引:4,他引:9
目的 为了深入研究大肠侧向发育型肿瘤(LST)细胞的生物学特性及其发生发展的机制。方法采用人LST组织进行肿瘤细胞建株及细胞分离与原代培养,传代至70代进行细胞鉴定.包括细胞的形态结构分析、染色体分析和免疫组化分析等,并与非LST细胞作对比。结果 LST细胞为上皮来源的肿瘤细胞,多形性上皮细胞占大多数,其有近似肿瘤细胞的生长特性,群体倍增时间为36h;染色体数量为42-66,85%在三倍体范围内,并具有异常染色体核型;免疫组织化学观察ESA、CK20均呈阳性;超微结构具肿瘤细胞样表现和特征。结论成功建立了1个LST细胞株,并命名为LST-R1细胞,为进一步深入研究LST细胞的生物学特性及大肠癌的发生发展机制奠定了基础。 相似文献
994.
Tzung-Jiun Tsai Hsien-Chung Yu Kwok-Hung Lai Gin-Ho Lo Ping-I Hsu Ting-Ying Fu 《台湾医志》2008,107(1):77-83
Upper gastrointestinal bleeding from primary aortoduodenal fistula (PADF) is unusual and fatal. The etiology of PADF from tuberculous aortitis is rare. We report a 69-year-old male patient who suffered recurrent hematemesis and hematochezia with hypovolemic shock of unknown origin. Initial endoscopy failed to lead to a diagnosis. A bleeder over the third portion of the duodenum was found after the third endoscopy. Exploratory laparotomy showed a ruptured aortic pseudoaneurysm with an aortoduodenal fistula. Dacron graft repair of the aorta and simple closure of the duodenal fistula were carried out. Pathologic examination revealed tuberculous aortitis. The patient survived and was symptom-free following operation and antituberculous therapy. Review of the literature revealed that the clinical presentations in this disorder are insidious. The endoscopic findings are atypical. We conclude that so-called "herald bleeding", a history of tuberculous infection or aortic aneurysm and a high degree of suspicion are critical for successful diagnosis. Early diagnosis and surgical exploration are needed for timely and successful management. 相似文献
995.
Maleimide and maleic anhydride derivatives from the mycelia of Antrodia cinnamomea and their nitric oxide inhibitory activities in macrophages 总被引:1,自引:0,他引:1
Wu MD Cheng MJ Wang BC Yech YJ Lai JT Kuo YH Yuan GF Chen IS 《Journal of natural products》2008,71(7):1258-1261
On cultivation of the fungus Antrodia cinnamomea (BCRC 36799) on a medium, the mycelium was extracted and evaluated for nitric oxide (NO) inhibitory activity. Bioactivity-directed fractionation led to the isolation of two new maleimide derivatives, antrocinnamomins A (1) and B (2), and two new maleic anhydride derivatives, antrocinnamomins C (3) and D (4), along with three known compounds, 3-isobutyl-4-[4-(3-methyl-2-butenyloxy)phenyl]furan-2,5-dione (5), 3-isobutyl-4-[4-(3-methyl-2-butenyloxy)phenyl]-1H-pyrrole-2,5-dione (6), and 3-isobutyl-4-[4-(3-methyl-2-butenyloxy)phenyl]-1H-pyrrol-1-ol-2,5-dione (7). Structural elucidation of compounds 1-4 was carried out by spectroscopic data. Compound 1 displayed significant inhibitory effect on nitric oxide (NO) production. 相似文献
996.
997.
998.
999.
Aim of study
In this study, we have investigated the analgesic and anti-arthritic effects of a traditional Chinese medicine (TCM) combination of Lingzhi and San Miao San (SMS) in a rat model of arthritis induced by Freund's complete adjuvant (FCA).Materials and methods
Sprague–Dawley rats were induced with monoarthritis by single unilateral injection of FCA into the knee joint. The TCM combination was administered to the rats daily by intraperitoneal injection (50 mg/(kg day)) or via oral administration (500 mg/(kg day)) for 7 days before induction of arthritis and 7 days after. Extension angle that provoked struggling behavior, and size and blood flow of the rat knees were measured to give indexes of allodynia, edema, and hyperemia, respectively. The extent of cell infiltration, tissue proliferation, and erosions of joint cartilage provided additional indexes of the arthritis condition.Results
FCA injection produced significant allodynia, edema, hyperemia, immune cell infiltration, synovial tissue proliferation, and erosions of joint cartilage in the ipsilateral knees compared with the contralateral saline-injected knees. Intraperitoneal injection of the TCM combination (50 mg/(kg day)) suppressed allodynia, edema, and hyperemia in the inflamed knees, and oral administration (500 mg/(kg day)) suppressed edema and hyperemia. Histological examination showed that the TCM administered by either route reduced immune cell infiltration and erosion of joint cartilage.Conclusions
These findings suggest the Lingzhi and SMS formulation has analgesic and anti-inflammatory effects in arthritic rat knees, and concur to previous clinical studies that showed the TCM combination reduced pain in rheumatoid arthritis patients, and extends its possible benefit to suppression of inflammatory symptoms in these patients. 相似文献1000.
Lai CS Mas RH Nair NK Majid MI Mansor SM Navaratnam V 《Journal of ethnopharmacology》2008,118(1):14-20
AIM OF THE STUDY: Typhonium flagelliforme (Lodd.) Blume (Araceae) is a Malaysian plant used locally to combat cancer. In order to evaluate its antiproliferative activity in vitro and to possibly identify the active chemical constituents, a bioactivity guided study was conducted on the extracts of this plant. MATERIALS AND METHODS: The active extracts of Typhonium flagelliforme were fractionated by flash column chromatography and each fraction was evaluated for antiproliferative activity using MTT assay. The apoptotic effect of the active fraction was determined microscopically and by using TUNEL colorimetric assay. GC-MS and NMR were used to determine the chemical constituents of this active fraction. RESULTS: Several fractions of the hexane and dichloromethane extracts were found to inhibit the growth of NCI-H23 non-small cell lung carcinoma cell line significantly, with IC(50)<15 microg/ml. However, most of these active fractions were also found to inhibit the growth of non-tumorigenic BALB/c 3T3 mouse fibroblast cell line except for fraction 21 of the dichloromethane extract (D/F21). This particular fraction was not only less cytotoxic to the non-tumorigenic cells, where the IC(50) was 48.6 microg/ml compared to IC(50) 7.5 microg/ml for NCI-H23, but it was also found to induce apoptosis in the cancer cell line. GC-MS analysis revealed that D/F21 contains hexadecanoic acid, 1-hexadecene, phytol and a derivative of phytol. The presence of non-saturated fatty acids in this fraction was confirmed by nuclear magnetic resonance spectroscopy. CONCLUSIONS: D/F21 was found to be the active and cancer cell line specific fraction of Typhonium flagelliforme. Its major chemical constituents had been determined spectroscopically. 相似文献