全文获取类型
收费全文 | 17318篇 |
免费 | 730篇 |
国内免费 | 137篇 |
专业分类
耳鼻咽喉 | 170篇 |
儿科学 | 362篇 |
妇产科学 | 130篇 |
基础医学 | 2172篇 |
口腔科学 | 306篇 |
临床医学 | 1097篇 |
内科学 | 4616篇 |
皮肤病学 | 446篇 |
神经病学 | 1410篇 |
特种医学 | 555篇 |
外科学 | 2793篇 |
综合类 | 46篇 |
一般理论 | 4篇 |
预防医学 | 382篇 |
眼科学 | 625篇 |
药学 | 1146篇 |
中国医学 | 31篇 |
肿瘤学 | 1894篇 |
出版年
2024年 | 13篇 |
2023年 | 108篇 |
2022年 | 261篇 |
2021年 | 445篇 |
2020年 | 214篇 |
2019年 | 272篇 |
2018年 | 347篇 |
2017年 | 273篇 |
2016年 | 368篇 |
2015年 | 414篇 |
2014年 | 500篇 |
2013年 | 617篇 |
2012年 | 1094篇 |
2011年 | 1157篇 |
2010年 | 684篇 |
2009年 | 575篇 |
2008年 | 1002篇 |
2007年 | 1142篇 |
2006年 | 1072篇 |
2005年 | 1217篇 |
2004年 | 1204篇 |
2003年 | 1081篇 |
2002年 | 1125篇 |
2001年 | 232篇 |
2000年 | 179篇 |
1999年 | 256篇 |
1998年 | 302篇 |
1997年 | 218篇 |
1996年 | 222篇 |
1995年 | 196篇 |
1994年 | 165篇 |
1993年 | 180篇 |
1992年 | 117篇 |
1991年 | 92篇 |
1990年 | 100篇 |
1989年 | 93篇 |
1988年 | 66篇 |
1987年 | 54篇 |
1986年 | 54篇 |
1985年 | 44篇 |
1984年 | 50篇 |
1983年 | 41篇 |
1982年 | 45篇 |
1981年 | 42篇 |
1980年 | 35篇 |
1979年 | 32篇 |
1978年 | 36篇 |
1977年 | 29篇 |
1976年 | 13篇 |
1975年 | 13篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.
Mariko Kobayashi Yukihiro Takahashi Makoto Ando Naoki Wada Masamitsu Murata Toshio Kikuchi 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(12):635-637
A 6 month-old male infant (weight: 4.5 kg) with congenital aortic stenosis underwent aortic valve replacement with a pulmonary
autograft (Ross procedure). The right ventricular outflow tract (RVOT) was reconstructed with a polytetrafluoroethylene (PTFE)-valved
equine pericardial conduit. At the age of 5, re-RVOT reconstruction with an equine pericardial patch bearing a PTFE monocusp
was required because of severe pulmonary stenosis resistant to 2 attempts of percutaneous transluminal pulmonary valvotomy.
Currently, at the age of 8, the degree of aortic regurgitation is trivial and the pulmonary autograft is free of functional
deterioration despite somatic growth. 相似文献
42.
43.
Hiroshi Okimura Masahiko Muto Makoto Ichimiya Satoshi Mogami Hiroaki Takahata Chidori Asagami 《The Journal of dermatology》1996,23(9):631-634
A 58-year-old Japanese woman who had herpes zoster in association with colitis was successfully treated with intravenously administrated acyclovir. Vesicular lesions with red haloes ranged from the left side of her buttock to the left extremity, corresponding to the L4 to S2 dermatomes. Her colitis was considered to have been induced by varicella-zoster virus, based on the facts that the clinical courses were correlated and that the innervation of the affected site of the colon corresponded to an infected dermatome (S2). 相似文献
44.
45.
Fujimoto Y Okuyama T Iijima M Tanaka T Horikawa R Yamada K Ogata T 《Molecular genetics and metabolism》2004,82(2):173-179
Although testicular development has been shown to be variably impaired in XY patients with distal 9p monosomy, ovarian and other genitourinary phenotype has poorly been studied in XX patients monosomic for the distal 9p region. Thus, we studied a 13-month-old infant with 46,XX,der(9)t(9;10)(p23;p13) (case 1) and an 11-year-old girl with 46,XX,der(9)t(9;16)(p23;q22) (case 2). Case 1 had primary hypogonadism (basal serum follicle stimulating hormone [FSH], 40.0 mIU/mL; leteinizing hormone [LH], 1.2 mIU/mL; estradiol [E2], <10 pg/mL), whereas case 2 had age-appropriate pubertal development (breast, Tanner stage 4; pubic hair, Tanner stage 3; menarche 11.7 years of age) and hormone values (FSH, 7.3 mIU/mL; LH, 6.7 mIU/mL; E2, 47 pg/mL). In addition, case 1 had hypoplastic labia majora, short distance between the vaginal orifice and the anus, and five renal cysts, and case 2 had anal atresia, short distance between the vaginal orifice and the anus, bilateral hydronephrosis of grade 3 with probable ureteropelvic junction stenosis, and renal dysfunction (serum creatinine, 1.52 mg/dL; urea nitrogen, 34.5mg/dL). Fluorescence in situ hybridization analysis for five regions and microsatellite analysis for 10 loci on 9p confirmed hemizygosity for the distal 9p region with the breakpoints between IFNA and D9S285 in case 1 and between D9S168 and D9S286 in case 2. The results, in conjunction with the previous data in XX patients with molecularly defined distal 9p monosomy, are consistent with the presence of a gene(s) involved in the development of indifferent gonad or subsequent ovarian differentiation in a approximately 11 Mb region distal to D9S168. In addition, it is possible that a gene(s) for anoperineal and renal development also maps distal to D9S168 and that for external genital development maps distal to D9S285 at the position approximately 16 Mb from the 9p telomere. 相似文献
46.
Studies have suggested that psoriasis vulgaris is mediated by type 1 T cells. In this study, we examined both chemokine receptor expression and intracellular cytokine production by circulating T cells to check the type 1/type 2 balance in psoriasis. CCR4+ and CXCR3+ T cells predominantly produced interleukin-4 and interferon-, respectively. The frequency of interferon--producing cells and that of CXCR3+ cells in circulating CD4+ T cells were similar for psoriatic patients and healthy control subjects. By contrast, the frequency of CCR4+CD8+ T cells and CCR4/CXCR3 ratio in circulating CD8+ T cells were significantly higher in psoriatic patients than in healthy control subjects. Analysis of intracellular cytokine production also indicated relative increase of type 2 CD8+ T (Tc2) cells in peripheral blood from psoriatic patients. The frequency of circulating Tc2 cells directly correlated with Psoriasis Area and Severity Index. Immunohistochemical analysis showed that not only CXCR3+CD8+ T cells but also a similar number of CCR4+CD8+ T cells infiltrated the psoriatic epidermis and dermis. Our findings suggest an increase in Tc2 cell number in blood from psoriatic patients, and the association of Tc2 cells with inflammation in psoriasis. 相似文献
47.
Honma Masamitsu; Hayashi Makoto; Shimada Hiroyasu; Tanaka Noriho; Wakuri Shinobu; Awogi Takumi; Yamamoto Koichi I.; Kodani Noriko-Ushio; Nishi Yoshisuke; Nakadate Masahiro; Sofuni Toshio 《Mutagenesis》1999,14(1):5-22
In order to evaluate the utility of the mouse lymphoma assay(MLA) for detecting in vitro clastogens and spindle poisonsand to compare it with the in vitro chromosomal aberration test(CA), we conducted an international collaborative study of theMLA that included 45 Japanese laboratories and seven overseaslaboratories under the cooperation of the Ministry of Healthand Welfare of Japan and the Japanese Pharmaceutical Manufacturer'sAssociation. We examined 40 chemicals; 33 were reportedly positivein the CA but negative in the bacterial reverse mutation assay,six were negative in both assays and one was positive in both.We assayed mutations of the thymidine kinase (TK) locus (tk)of L5178Y tk+/ mouse lymphoma cells using the microwellmethod. According to our standard protocol, cells were exposedto the chemical for 3 h, cultured for 2 days and TK-deficientmutants were expressed in 96-well plates under trifluorothymidine.Each chemical was coded and tested by two or three laboratories.Among the 34 CA-positive chemicals, positive MLA results wereobtained for 20 and negative results were obtained for nine.The remaining five chemicals were inconclusive or equivocalbecause of discrepant inter-laboratory results or reproduceddiscrepant results, respectively. Among the six CA-negativechemicals, one was negative in the MLA, two were positive andthree were inconclusive. Thus, the MLA could detect only 59%(20/34) of CA-positive chemicals. We concluded that the MLAwas not as sensitive as the CA. Some MLA-negative chemicalsevoked positive responses in the CA only after long continuoustreatment. These might also be genotoxic in the MLA with longcontinuous treatment. Improvement of the MLA protocol, includingalteration of the duration of the treatment, might render theMLA as sensitive as the CA.
8 To whom correspondence should be addressed. Tel: +81 3 37009847; Fax: +81 3 3700 2348; Email: sofuni{at}nihs.go.jp 相似文献
48.
Ikegaya H Iwase H Zheng HY Nakajima M Sakurada K Takatori T Fukayama M Kitamura T Yogo Y 《Journal of virological methods》2005,126(1-2):37-43
Recently genotyping of JC virus (JCV) DNA in renal tissue was reported to be useful to identify the geographic origin of unidentified cadavers. In the above study, autopsied tissue samples without storage or stored in a frozen state were used. This study examined JCV DNA sequence modifications caused by formalin-fixation, in an attempt to elucidate whether formalin-fixed, paraffin-embedded tissue samples can also be used to determine the genotypes of JCV DNA in the kidney. In four cases, a 610 bp typing region of the JCV genome was PCR-amplified from renal tissues stored for 1 year in three different states: frozen at -80 degrees C [Amaker, B.H., Chandler, F.W., Huey, L.O., Colwell, R.M., 1997. Molecular detection of JC virus in embalmed, formalin-fixed, paraffin-embedded brain tissue. J. Forensic Sci., 1157-1159], formalin-fixed, paraffin-embedded [Ault, G.S., Stoner, G.L., 1992. Two major types of JC virus defined in progressive multifocal leukoencephalopathy brain by early and late coding region DNA sequences. J. Gen. Virol. 73, 2669-2678], and soaked in 5% formalin [Baksh, F.K., Finkelstein, S.D., Swalskey, P.A., Stoner, G.L., Ryschkewitsch, C.F., Randhawa, P.R., 2001. Molecular genotyping of BK and JC virus in human polyomavirus-associated interstitial nephritis after renal transplantation. Am. J. Kidney Dis. 38 (2), 354-365]. The amplified fragments were cloned, and the resultant clones were sequenced. In frozen samples, single sequences ('original' sequences) were detected in all cases. In formalin-fixed, paraffin-embedded samples, not only the original sequences but also those with 1-6 base substitutions were detected. From formalin-soaked samples, the original sequences and those with 1-5 and 10-13 substitutions were detected. The genotyping of JCV DNA was not hampered by the presence of 1-6 substitutions, but a shift in JCV genotypes was observed in sequences with 10-13 substitutions. Thus, it was concluded that the genotypes of JCV DNA in the kidney can be determined only with specimens stored in a frozen state or formalin-fixed for a short time. 相似文献
49.
The inhibitory effects of bovine milk κ‐casein and its enzymatic digests on the proliferative responses of mouse spleen lymphocytes induced or not induced by mitogens were studied with a colorimetric assay using 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl tetrazolium bromide (MTT). κ‐Casein and its glyco‐macropeptide (residues 106–169) inhibited the lipopolysaccharide (LPS)‐induced proliferative response, but the inhibitory effect was lost significantly after neuraminidase and chymotrypsin digestions. In contrast, trypsin and pronase digestions of K‐casein increased inhibitory effects. The pronase digest inhibited the proliferative responses not only induced by LPS but also in the absence of mitogen or when induced by concanavalin A and phytohemagglutinin. The pronase digest seemed to possess weak cytotoxity for lymphocytes. The inhibitory peptide was a glycopeptide(s) having specific size, and the inhibitory effects were reduced significantly by neuraminidase and chymotrypsin digestions. Moreover, similar inhibitory effects on proliferation of lymphocytes were observed in pronase‐digested bovine milk αs1‐casein and β‐casein. These findings suggest that some peptides produced from milk caseins by the action of gastrointestinal proteinases might contribute to down‐regulate the immune response of neonates. 相似文献
50.
Makoto Bannai Katsushi Tokunaga Ling Lin Atsuko Ogawa Kiyoshi Fujisawa Takeo Juji 《Human immunology》1996,46(2):107-113
We developed a system for discriminating HLA-B40, B18, B27, and B37 alleles using a two-step PCR method followed by SSCP analysis. Fragments (0.8 kb) including exon 2, intron 2, and exon 3 were amplified in the first PCR. We used two sets of primers, one specific for HLA-B60-related alleles and the other specific for HLA-B6l-related, B18, B27, and B37 alleles. No amplifications of other class I genes or pseudogenes were observed. In the second PCR, exon 2 and exon 3 were amplified separately, using diluents of the first PCR products as templates. HLA-B6l-related, B18, B27, B37, and B60-related alleles were clearly discriminated in the SSCP analysis of the second PCR products. In a population study in which B6l alleles were analyzed, B*4003 was detected in two Japanese individuals in addition to two B6l alleles previously reported to occur in Japanese, B*4002 and B*4006. The relative frequencies of B*4002, B*4006, and B*4003 in Japanese were 58, 35, and 6%, respectively. The individuals having B*4003 are the first non-South Americans in whom this allele has been detected. The SSCP banding patterns of 18 HLA-B60-positive Japanese population samples were identical to those of a B*40012 sample for both exon 2 and exon 3. We also demonstrated that the B37 allele occurring in some Japanese is B*3701. 相似文献