全文获取类型
收费全文 | 5484篇 |
免费 | 296篇 |
国内免费 | 58篇 |
专业分类
耳鼻咽喉 | 51篇 |
儿科学 | 206篇 |
妇产科学 | 62篇 |
基础医学 | 678篇 |
口腔科学 | 67篇 |
临床医学 | 298篇 |
内科学 | 1752篇 |
皮肤病学 | 80篇 |
神经病学 | 437篇 |
特种医学 | 175篇 |
外科学 | 841篇 |
综合类 | 9篇 |
预防医学 | 114篇 |
眼科学 | 113篇 |
药学 | 307篇 |
中国医学 | 6篇 |
肿瘤学 | 642篇 |
出版年
2023年 | 33篇 |
2022年 | 40篇 |
2021年 | 133篇 |
2020年 | 84篇 |
2019年 | 105篇 |
2018年 | 115篇 |
2017年 | 126篇 |
2016年 | 135篇 |
2015年 | 126篇 |
2014年 | 161篇 |
2013年 | 225篇 |
2012年 | 338篇 |
2011年 | 398篇 |
2010年 | 238篇 |
2009年 | 181篇 |
2008年 | 311篇 |
2007年 | 346篇 |
2006年 | 360篇 |
2005年 | 382篇 |
2004年 | 352篇 |
2003年 | 351篇 |
2002年 | 314篇 |
2001年 | 102篇 |
2000年 | 94篇 |
1999年 | 90篇 |
1998年 | 80篇 |
1997年 | 59篇 |
1996年 | 49篇 |
1995年 | 45篇 |
1994年 | 53篇 |
1993年 | 56篇 |
1992年 | 44篇 |
1991年 | 35篇 |
1990年 | 33篇 |
1989年 | 29篇 |
1988年 | 18篇 |
1987年 | 22篇 |
1986年 | 31篇 |
1985年 | 12篇 |
1984年 | 8篇 |
1983年 | 9篇 |
1982年 | 13篇 |
1981年 | 10篇 |
1979年 | 10篇 |
1975年 | 11篇 |
1974年 | 8篇 |
1973年 | 8篇 |
1971年 | 6篇 |
1969年 | 6篇 |
1967年 | 6篇 |
排序方式: 共有5838条查询结果,搜索用时 33 毫秒
1.
2.
3.
4.
Satoshi Iyama Yasuo Takahashi Naoaki Shintani Koshi Fujikawa Syunichi Ohkubo Yasushi Sato Tsutomu Sato Yasuhiro Sato Keisuke Ohnuma Yoshiro Niitsu 《Nihon Shokakibyo Gakkai zasshi》2006,103(10):1163-1168
We report a case of biliary cystadenocarcinoma which recurred 41 months postoperatively. A 60-year-old woman was admitted for further examination of multiple metastatic tumors and a large amount of ascites. Systemic administration of 5FU and CDDP caused her CEA level to decrease gradually and abdominal computed tomography revealed considerable reduction of the metastatic tumors and ascites. Since her general condition had improved, chemotherapy was continued in the outpatient clinic. 相似文献
5.
Immunohistochemical characterization of extracellular matrix in the developing human cornea 总被引:4,自引:0,他引:4
Collagen, fibronectin and laminin are important components of the extracellular matrix of the human cornea. We used the immunofluorescence technique with polyclonal antibodies directed against these proteins and to bullous pemphigoid antigen (BPA), in order to study their distribution in human corneas from 8 weeks of gestation to term and in adult corneas. Immunoreactivity was observed with antibodies to type I collagen in the limbus and the corneal stroma at 8 weeks of gestation. At 11 weeks of gestation it was found in epithelial basement membrane (EBM) and Descemet's membrane (DM) and continued thus throughout fetal and adult life. Type II collagen was not detected in fetal or adult cornea. Type III collagen was detected during 8-20th weeks of gestation in the EBM, DM and stroma. After 27th weeks of gestation, type III collagen could no longer be detected in the central cornea. Type IV collagen was detected in the EBM as early as 8 weeks of gestation and remained positive throughout fetal and adult life. Descemet's membrane was negative for type IV collagen at 8 weeks of gestation and became positive thereafter. Immunostaining for fibronectin in DM was negative at 8 weeks of gestation, followed by patchy staining of corneal stroma and EBM up to the age of 37 weeks of gestation. Staining in the EBM was negative or variable up to 70 years of age, and then became positive again in a 77 year old individual. Staining for LN was positive in the EBM after 8 weeks of gestation. Staining was negative in DM at that age, but became positive after 9 weeks of gestation. Staining for BPA was negative at 8-9 weeks of gestation, then gradually became positive. 相似文献
6.
Hata T Kuno A Dai SY Inubashiri E Hanaoka U Kanenishi K Yamashiro C Tanaka H Yanagihara T 《The journal of obstetrics and gynaecology research》2007,33(5):600-605
AIM: The objective of this longitudinal study was to evaluate the growth of the fetal spleen in normal pregnancies, using three-dimensional ultrasound. METHODS: Three-dimensional sonographic examinations were performed on 14 appropriate-for-gestational-age fetuses. Fetal splenic volume was measured every 2-3 weeks after 20 weeks of gestational age until delivery. RESULTS: Curvilinear relationships were found between the gestational age and splenic volume (R(2) = 80.2%, P < 0.0001), and normal ranges of splenic volume measurements for estimating the growth of the fetal spleen during normal pregnancy were generated. We found that the splenic volume calculation based on the equation for the volume of the ellipsoid by conventional two-dimensional ultrasound in previous investigations is about twice as large as that using three-dimensional ultrasound in our study, whereas the present data described in this study is quite comparable with previous data from an autopsy series. CONCLUSION: Our findings suggest that the standard curve for the fetal splenic volume using three-dimensional ultrasound provides a superior means for evaluating the normal splenic growth in the fetus and for identifying splenic abnormalities in utero. However, the data and its interpretation in our study should be taken with some degree of caution because of the small number of subjects studied. Further studies involving a larger sample size would be needed to confirm these findings. 相似文献
7.
The association of MTHFR and CBS variants with the doubling time and responsiveness to several chemodrugs was analyzed in 26 human cancer xenografts. The tumors homozygous for the absence of insertion (NN) for the CBS 844ins68bp were more chemosensitive than those with insertion (NI) to TS-1 (P=0.0048), suggesting a potential effect of this variant on fluoropyrimidine efficacy. Furthermore, the doubling time of tumors with a variant C allele (AC or CC) in MTHFR-A1298C was significantly longer than that of tumors with a normal allele (AA) (P=0.0008). Twenty-nine cellular proliferation-related genes were associated with MTHFR-A1298C genotyping and with the doubling time. 相似文献
8.
Chieko Nakamura Yoshiharu Kawaguchi Hirokazu Ishihara Hiroshi Sainoh Tomoatsu Kimura 《Journal of orthopaedic science》2004,9(6):629-634
We report two cases of rheumatoid arthritis (RA) with upper thoracic myelopathy and a review of the literature. Clinical data of a 47-year-old woman (case 1) and a 54-year-old woman (case 2) are described. Case 1 showed a transverse-type myelopathy at the T2 segment level of the spinal cord and case 2 had the same type of myelopathy at the T4 segment level. Case 1 had anterior vertebral subluxation of C7 due to marked vertebral collapse and Case 2 had subluxation of T2 with vertebral destruction. These two patients had the mutilating type of RA with multilevel spontaneous fusion in the cervical spine. The lesions in the thoracic spine might be caused by the severe destructive inflammation that is characteristic in mutilating disease. The vertebral collapse might lead to subluxation of the upper thoracic vertebra, resulting in spinal cord compression. Upper thoracic subluxation might be caused by vertebral collapse due to RA and the increased motion as a compensation for decreased mobility caused by spontaneous fusion in the cervical spine. 相似文献
9.
Four novel mutations in the thiazide-sensitive Na-Cl co-transporter gene in Japanese patients with Gitelman's syndrome. 总被引:3,自引:1,他引:2
Nobuki Maki Atsushi Komatsuda Hideki Wakui Hiroshi Ohtani Akihiko Kigawa Namiko Aiba Keiko Hamai Mutsuhito Motegi Akihiko Yamaguchi Hirokazu Imai Ken-ichi Sawada 《Nephrology, dialysis, transplantation》2004,19(7):1761-1766
BACKGROUND: Gitelman's syndrome (GS) is an autosomal recessive disorder resulting from inactivating mutations in the thiazide-sensitive Na-Cl co-transporter (NCCT) gene. To date, almost 90 mutations have been identified. It is possible that there is a population-specific distribution of mutations. In this study, we analysed mutations in the NCCT gene of seven Japanese patients with GS. METHODS: Peripheral blood mononuclear cells were isolated from patients with GS, their family members and healthy control subjects. A mutation analysis of the NCCT gene was performed completely by direct automated sequencing of polymerase chain reaction-amplified DNA products. In patients with a deletion or splice site mutation, we undertook cDNA sequence analysis. RESULTS: We identified nine mutations. Five of them [c.185C>T (Thr60Met), c.1712C>T (Ala569Val), c.1930C>T (Arg642Cys), c.2552T>A (Leu849His) and c.1932delC] have been reported in Japanese patients, but not in GS patients from other ethnic groups. The remaining four mutations [c.7A>T (Met1Leu), c.1181_1186+20del26, c.1811_1812delAT and IVS16+1G>A] were novel. In cDNA derived from a patient with c.1181_1186+20del26, a deletion of exon 9 and a frameshift at the start of exon 10 were observed. In cDNA derived from patients with IVS16+1G>A, an additional 96 bp insertion between exons 16 and 17 was observed. Six out of seven patients were compound heterozygotes, and the remaining one carried a single heterozygous mutation. CONCLUSIONS: We found four novel mutations in the NCCT gene in seven Japanese patients with GS. Moreover, our study suggests that the distribution of mutations in the NCCT gene in Japanese GS patients potentially differs from that in other populations. 相似文献
10.
Tetsuji Kai Yang Il Kim Hirokazu Kitamura Katsunori Kawano Seigo Kitano 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(4):423-430
There is a growing body of evidence that the cytokine, tumor necrosis factor-α (TNF-ga), plays an important role in the development
of hepatic ischemia/reperfusion injury. We found that the immunosuppressants, cyclosporine-A (CsA), azathioprine, and FK506,
have protective effects on such injury. The purpose of the present study was to elucidate mechanisms involved in these beneficial
effects of the immunosuppressant, CsA, on liver injury following cold preservation and transplantation, with special reference
to the suppression of TNF-α release. Rat livers were stored in Euro-Collins solution (EC) at 4°C for 6h and orthotopically
transplanted. The animals allotted to two groups: group A (untreated controls) and group B (CsA pretreatment of recipients).
CsA (10 mg/kg, p.o.) was given for 3 consecutive days preoperatively. CsA pretreatment of the recipients significantly improved
the 2-week survival rate (0/6 for group A, 3/6 for group B;P<0.05) and this was associated with a significant decrease in serum TNF-α levels 2h posttransplantation (group A, 69.8±15.7
pg/ml; group B, 22.8±6.8; mean±SEM;n=12 each;P<0.05) and amelioration of sinusoidal endothelial injury, assessed by electron microscopy. Plasma endotoxin levels following
reperfusion of the grafts were not altered by the CsA therapy. Morphologically, CsA pretreatment of the recipients did not
alter activation of Kupffer cells. CsA pretreatment of the recipient aids in preventing cold preservation/reperfusion injury
of the liver graft, possibly by modulating effects of TNF-α. 相似文献