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51.
Ishikawa Y Furuta R Miyoshi T Satoh Y Okumura S Nakagawa K Tsuchiya E 《Cancer letters》2002,187(1-2):47-51
To better understand causative relations of smoking to lung adenocarcinomas, the frequency of loss of heterozygosity (LOH) of all autosomal chromosomes was compared among the three grades of histological differentiation with 119 pulmonary adenocarcinomas (AC) and 41 squamous cell carcinomas (SCC), using Southern blotting. The fractional allelic loss (FAL) values, defined as (number of chromosome arms with LOH)/(number of informative arms), and smoking index (a product of number of cigarettes per day and duration in years) for all ACs were 0.19 and 520 whereas those for SCCs were 0.34 and 1,160, respectively. Those for well- (n=33), moderately (n=63) and poorly (n=23) differentiated ACs were 0.100, 0.197, 0.295 and 310, 480, 1,010, respectively. These results showed that less differentiated ACs are more similar to SCC in terms of LOH frequency and smoking. 相似文献
52.
Mutation,DNA strand cleavage and nitric oxide formation caused by N-nitrosoproline with sunlight: a possible mechanism of UVA carcinogenicity 总被引:1,自引:0,他引:1
Arimoto-Kobayashi S Ando Y Horai Y Okamoto K Hayatsu H Lowe JE Green MH 《Carcinogenesis》2002,23(9):1537-1540
N-Nitrosoproline (NPRO) is endogenously formed from proline and nitrite. NPRO has been reported to be nonmutagenic and noncarcinogenic. In this study, we have detected the direct mutagenicity of NPRO plus natural sunlight towards Salmonella typhimurium. Furthermore, formation of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG), a mutagenic lesion, was observed in calf thymus DNA treated with NPRO plus simulated sunlight. The treatment with NPRO and sunlight induced single strand breaks in the superhelical replicative form of phage M13mp2 DNA. Single-strand DNA breaks also occurred in the human fibroblast cells on treatment with NPRO plus UVA, as detected by the comet assay. An analysis using scavengers suggested that both reactive oxygen species and NO radical mediate the strand breaks. The formation of nitric oxide was observed in NPRO solution irradiated with UVA. We analyzed the photodynamic spectrum of mutation induction and DNA breakage using monochromatic radiation at a series of wavelengths between 300 and 400 nm. Both mutation frequencies and DNA breakage were highest at the absorption maximum of NPRO, 340 nm. The co-mutagenic and co-toxic actions of NPRO and sunlight merit attention as possible mechanisms increasing the carcinogenic risk from UVA irradiation. 相似文献
53.
54.
Antihepatotoxic actions of the papyriogenins and papyriosides from Tetrapanax papyriferum leaves were examined utilizing carbon tetrachloride (CCl4)- and galactosamine (GalN)-induced cytotoxicity in primary cultured rat hepatocytes. Remarkable antihepatotoxic effects were observed with papyriogenin B, papyriogenin A, propapyriogenin A2, papyriogenin C, 11-dehydropropapyriogenin A2, 16-epi-saikogenin C and propapyriogenin A1 in the CCl4-induced cytotoxicity assay, and papyriogenin A, propapyriogenin A1 and propapyriogenin A2 were active in preventing GalN-induced cytotoxicity although these triterpenoids were rather cytotoxic at a higher dose in the latter assay. Structure-activity relationship is discussed. 相似文献
55.
M. Nagata I. Semha K. Ooya A. Urago S. Yonezawa K. Sakae 《Journal of oral pathology & medicine》1984,13(6):560-572
This report presents a rare malignant endothelial neoplasm which arose at the site of a pre-existing lymphangioma. The lymphangioma was located on the right buccal miicosa, and the malignant neoplasm arose 17 years after irradiation of the initial tumor. Clinical, light microscopic and immunohistochcmical (Factor VIII-related antigen and Ulex europueus Agglutinin-1) studies were made, together with observations by transmission and scanning electron microscopy. These studies provide evidence that this malignant neoplasm was well-differentiated and had not yet lost the characteristics of normal lymphatic cells. 相似文献
56.
M Hongo R Shimizu K Sakae S Hayashi M Yoshinouchi Y Mitsui 《The Japanese journal of antibiotics》1984,37(12):2391-2396
One gram of ceftriaxone (Ro 13-9904, CTRX), a new cephalosporin antibiotic, was given intravenously to a total of 25 patients prior to abdominal total hysterectomy for uterine myoma with or without small benign ovarian tumor. Bilateral uterine arteries were clamped at 0.5, 1, 2, 6, 12 and 24 hours after administration, and serum samples and uterine tissues were taken for the measurement of CTRX concentration by bioassay method. A little difference was found in the serum concentration between cubital venous and uterine arterial serum, the half-lives being 8.0 and 7.9 hours, respectively. The initial concentrations were estimated to be 153 micrograms/ml and 160 micrograms/ml, respectively. The tissue peak concentrations were obtained at 30 minutes in the myometrium, portio vaginalis, oviduct and ovary, and at 1 hour in the endometrium and cervix uteri. These were 41, 51, 51, 39, 42 and 47 micrograms/g, respectively. The tissue concentrations after peak decreased in the same manner as the serum concentrations. Judging from its favorable transfer into the uterine tissues, CTRX was evaluated to be clinically useful in the treatment of obstetrical and gynecological infections. 相似文献
57.
Iizasa T Baba M Saitoh Y Suzuki M Haga Y Iyoda A Chang H Hiroshima K Itoga S Tomonaga T Nomura F Fujisawa T 《Oncology reports》2005,14(4):919-923
Cytochrome P450 2E1 (CYP2E1) catalyzes the metabolic activation of the procarcinogen, N-nitrosodimethylamine, and cytotoxic carbon tetrachloride compounds. A tandem repeat polymorphism in the 5'-flanking region of the CYP2E1 gene was investigated in non-small cell lung carcinoma (NSCLC) patients to clarify the relationship between CYP2E1 gene polymorphism and lung cancer susceptibility. Blood samples were taken from 236 healthy control subjects (192 males and 44 females) and 111 patients (78 males and 33 females) who underwent surgery for NSCLC in Japan. DNA was isolated from these samples and the 5'-flanking region of the CYP2E1 gene was amplified by polymerase chain reaction and examined for tandem repeat polymorphisms using DNA fragment analysis. Sequence analysis confirmed the presence of three alleles, A2, A3, and A4 (361, 367, and 457 bp, respectively), with four genotypes observed in the lung cancer group and five genotypes in the control group. There was a statistically significant difference in genotype distribution between the lung adenocarcinoma and control group (P=0.0088, A4/A4 vs. non-A4/A4). In the lung adenocarcinoma group, the univariate risk estimates for the A4/A4 subgroup compared to the most common subgroup (A2/A2) was 4.300 (95% confidence interval = 1.358-13.618, P=0.0131). We conclude that the A4/A4 genotype of the 5'-flanking region of CYP2E1 was significantly more frequent in lung adenocarcinoma cases than in healthy controls and, therefore, may be involved in the development of lung adenocarcinoma. 相似文献
58.
Tanaka S 《Clinical calcium》2005,15(7):62-66
The vaccination method is used to induce antibody response against disease-related proteins by immunization with modified pathological antigen as preventive therapy to acquire disease resistance. A RANKL vaccine was developed by modifying the soluble TNF-like domain of murine RANKL to incorporate a promiscuous Th epitope. Immunization with RANKL vaccine prevented pathological bone resorption in arthritic mice or ovariactomized mice. 相似文献
59.
Tsuneo Morishima Takayuki Ichikawa Hideaki Yamaguchi Mitsunobu Miyazu Shoichi Nagayoshi Takao Ozaki Shin Isomura Sakae Suzuki 《European journal of pediatrics》1978,129(4):259-265
We had an outbreak of acute infantile gastroenteritis accompanied by milky-white stool (called Hakuri in Japanese) during the winters of 1976 and 1977. Stool specimens collected from 72 cases of Hakuri were studied by negative-staining electron microscopy. Rotavirus was detected with a very high frequency (89%).Rotavirus obtained from one of the patients was isolated and passaged in cultures of primary human embryonic kidney cells. Viral antigens could be detected in the cytoplasm of the cells by indirect immuno-fluorescence. The fluorescence-positive cells increased in number with repeated passage.Serum anti-viral activities in 11 patients were titrated by indirect immuno-fluorescence, using the cells infected with the passaged rotavirus. All 11 patients developed IgM responses in the convalescent phase. However, in 4 of the 11 patients, no IgG responses were detected even 2–3 weeks after the onset of illness. The reinfection which has occasionally be seen in our country may be related to these poor IgG responses. 相似文献
60.
Sato K Morishita T Nobusawa E Tonegawa K Sakae K Nakajima S Nakajima K 《Epidemiology and infection》2004,132(3):399-406
Sera from 27 children and eight older persons, which had been collected in 1998 and 1999 and showed haemagglutination-inhibition (HI) activity against influenza A/Sydney/5/97 (H3N2) strain, were characterized with a binding assay using chimeric haemagglutinin (HA) proteins between A/Aichi/2/68 (A/AI/68) and A/Sydney/5/97 (A/SD/97) strains. Sera from the young children had a tendency to recognize only the antigenic site B1 of the HA1 region. On the other hand, sera of the older individuals were fully reactive to all antigenic sites of HA1 except antigenic site D. Recent epidemic strains, A/Panama/2007/99 (A/PM/99)-like viruses have differences in amino acids in antigenic sites A, C, and B2 but not B1. However, human antisera obtained even from young children had HI activity to Panama-like viruses. The limited epidemic of A/PM/99-like viruses may have been due to the existence of antibody against B1, which had been produced in response to infection by the A/SD/97-like viruses. 相似文献