全文获取类型
收费全文 | 1573篇 |
免费 | 72篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 11篇 |
妇产科学 | 5篇 |
基础医学 | 196篇 |
口腔科学 | 20篇 |
临床医学 | 106篇 |
内科学 | 607篇 |
皮肤病学 | 7篇 |
神经病学 | 61篇 |
特种医学 | 55篇 |
外科学 | 265篇 |
综合类 | 5篇 |
预防医学 | 43篇 |
眼科学 | 11篇 |
药学 | 74篇 |
中国医学 | 18篇 |
肿瘤学 | 170篇 |
出版年
2023年 | 11篇 |
2022年 | 25篇 |
2021年 | 41篇 |
2020年 | 22篇 |
2019年 | 37篇 |
2018年 | 38篇 |
2017年 | 21篇 |
2016年 | 27篇 |
2015年 | 38篇 |
2014年 | 57篇 |
2013年 | 77篇 |
2012年 | 97篇 |
2011年 | 112篇 |
2010年 | 69篇 |
2009年 | 57篇 |
2008年 | 104篇 |
2007年 | 109篇 |
2006年 | 100篇 |
2005年 | 119篇 |
2004年 | 87篇 |
2003年 | 84篇 |
2002年 | 78篇 |
2001年 | 13篇 |
2000年 | 26篇 |
1999年 | 22篇 |
1998年 | 23篇 |
1997年 | 13篇 |
1996年 | 13篇 |
1995年 | 15篇 |
1994年 | 6篇 |
1993年 | 17篇 |
1992年 | 6篇 |
1991年 | 12篇 |
1990年 | 6篇 |
1989年 | 9篇 |
1988年 | 10篇 |
1987年 | 16篇 |
1986年 | 7篇 |
1985年 | 7篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 4篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1971年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有1660条查询结果,搜索用时 15 毫秒
91.
Imade GE Badung B Pam S Agbaji O Egah D Sagay AS Sankalé JL Kapiga S Idoko J Kanki P 《Clinical and diagnostic laboratory immunology》2005,12(1):224-227
We compared two techniques for CD4 T-lymphocyte counting: flow cytometry (Cyflow) and magnetic beads (Dynabead). Similar results with good correlation were obtained from the 40 adult blood samples counted (P=0.057, r=0.93). The Cyflow technique is more precise and cost-effective than the Dynabead method ($3 to $5 versus $12 to $22 per test, respectively), since as many as 200 samples can be measured per day. 相似文献
92.
Fukuda T Yamashita Y Nagamitsu S Miyamoto K Jin JJ Ohmori I Ohtsuka Y Kuwajima K Endo S Iwai T Yamagata H Tabara Y Miki T Matsuishi T Kondo I 《Brain & development》2005,27(3):211-217
A total of 45 different mutations of methyl-CpG-binding protein 2 gene (MECP2) were identified in 145 of 219 Japanese patients with typical or atypical Rett syndrome (RTT) (66.2%). A missense mutation, T158M was the most common mutation of MECP2, identified in 22 (19.1%) patients, followed by four nonsense mutations, R168X (14.8%), R270X (13.0%), R255X (9.6%), and R294X (6.1%) in 115 patients with classical RTT. Two missense mutations, R133C (33.3%) and R306C (23.3%), and a nonsense mutation, R294X (13.3%), were common in 30 patients with atypical RTT, including the preserved speech variant (PSV). Frameshift mutations due to nucleotide deletion or insertion were identified in 22 patients with MECP2 mutations, and one of them had a 3.6 kb deletion encompassing exons 3 and 4. Three patients with classical RTT had a splicing anomaly. The wide spectrum of phenotypic variability in patients with RTT has been considered to be correlated with the mutation type and location in MECP2, and X-inactivation. However, most patients showed a random X-inactivation pattern evaluated by an androgen receptor gene polymorphism in this study, suggesting that a skewed X-inactivation might not be a main modification factor on clinical phenotypes of RTT. In addition, three new missense mutations, P176R, A378V and T479M, were identified in patients with RTT, but also in healthy Japanese, indicating that these mutations are non-pathogenic in Japanese. Information about rare polymorphic variations is very important for the molecular diagnosis of RTT, although rare polymorphic variants might differ among ethnic groups. 相似文献
93.
94.
Murao S Makino H Kaino Y Konoue E Ohashi J Kida K Fujii Y Shimizu I Kawasaki E Fujiyama M Kondo S Tanaka K Tarumi Y Seto I Kato K Ohno K Kusunoki Y Ebisui O Takada Y Tanabe K Takemoto K Onuma H Nishimiya T Osawa H 《Diabetes》2004,53(10):2684-2690
To clarify heterogeneity in Japanese adult-onset type 1 diabetes, we analyzed the HLA-DR and -DQ haplotypes, depending on the clinical phenotype, and compared them with those in childhood-onset type 1 diabetes (CO). The patients in a previously reported Ehime Study were divided into subgroups by the mode of onset of diabetes: 68 acute-onset type 1 diabetic patients (AO) and 28 slowly progressive type 1 diabetic patients (SO). HLA haplotypes were compared with those of 80 CO patients and 190 control subjects. Two major susceptible HLA haplotypes in the Japanese, DRB1*0405-DQB1*0401 (DR4) and DRB1*0901-DQB1*0303 (DR9), were significantly increased in the AO and CO groups, but only DR9 was increased in the SO group. AO subjects had a higher frequency of DR9 than CO subjects. Accordingly, the DR9:DR4 frequency increased with increasing age of onset. Another susceptible haplotype, DRB1*0802-DQB1*0302 (DR8), was involved only in the CO group. Analysis of haplotype combinations revealed that DR4 and DR9 had significant dosage effects on the AO and CO groups (P < 0.0001), but only DR9 had such an effect in the SO group (P < 0.03). These results suggest differences in the contribution of HLA class II haplotypes to susceptibility of type 1 diabetes depending on the clinical phenotype and also indicate that HLA class II haplotypes may be associated with the onset age of type 1 diabetes. 相似文献
95.
Kawate K Tanaka Y Ohmura T Hiyoshi N Yajima H Tomita Y Takakura Y 《Clinical orthopaedics and related research》2004,(426):151-158
We reviewed the long-term outcomes of intertrochanteric valgus femoral osteotomies in patients with arthritic hips to clarify any influencing factors. One hundred six patients (127 hips) were followed up during an average of 25 years. The average age of the patients at surgery was 42 years. The preoperative extent of degenerative change was classified radiologically into one of four grades according to the criteria of T?nnis. Radiographic measurements of acetabular coverage were made using AP radiographs obtained immediately after surgery. Thirty-eight patients (41 hips) had total hip arthroplasties; the 25-year survival rate was 69%. Radiologic evaluations of patients with mild preoperative degenerative changes (T?nnis Grade 1) improved and good clinical outcomes were obtained. In addition, radiologic evaluations of patients whose hips had better acetabular coverage (center-edge angle > 0 degrees, sharp angle < 50 degrees, or acetabular head index > 60%) also improved. However, radiographic measurements did not influence clinical scores. The mean score of patients younger than 50 years at surgery was higher than patients older than 50 years. The mean score of patients with unilateral hip involvement was higher than patients with bilateral involvement. Therefore, valgus osteotomies seem appropriate for younger patients with unilateral involvement. 相似文献
96.
Nishida S Kinoshita H Okinami T Kunishima Y Segawa T Ito N Yamamoto S Kamoto T Habuchi T Ogawa O 《Hinyokika kiyo. Acta urologica Japonica》2004,50(6):445-447
A 58-year-old female presented with a well-encapsulated tumor in the left renal hilum on computed tomography (CT). On magnetic resonance imaging (MRI), the tumor showed low intensity on the T1-weighted image, high intensity on the T2-weighted image. Laparoscopic radical nephrectomy was performed because we could not exclude the possibility of malignancy such as renal cell carcinoma. Histopathological examination revealed that the tumor was a benign Schwannoma. Although renal hilum is a common site of renal schwannoma, it is difficult to differentiate benign tumors from malignant ones, and then nephrectomy is usually performed. 相似文献
97.
Ohsaki A Imai Y Naruse M Ayabe S Komiyama K Takashima J 《Journal of natural products》2004,67(3):469-471
Four new triterpenoids with various skeletons, maytefolins A-C (1-3) and uvaol-3-caffeate (4), were isolated from the leaves of a Brazilian medicinal plant, Maytenus ilicifolia, together with five known triterpenoids. Of these triterpenoids only erythrodiol exhibited significant cytotoxicity against KB/S, KB/VJ300, and KU 19-20 cells. 相似文献
98.
Characteristics of patients with chronic hepatitis C who develop hepatocellular carcinoma after a sustained response to interferon therapy 总被引:2,自引:0,他引:2
Makiyama A Itoh Y Kasahara A Imai Y Kawata S Yoshioka K Tsubouchi H Kiyosawa K Kakumu S Okita K Hayashi N Okanoue T 《Cancer》2004,101(7):1616-1622
BACKGROUND: The objective of the current study was to determine the characteristic features of sustained responders who develop hepatocellular carcinoma after treatment with interferon for chronic hepatitis C. METHODS: This study included 3626 patients with chronic hepatitis C who had received interferon monotherapy. Cox proportional hazards analysis was used to compare sustained responders who did and did not develop hepatocellular carcinoma, and nonsustained responders who developed hepatocellular carcinoma in a multicenter, retrospective cohort study. RESULTS: Among 1197 sustained responders, 27 patients developed hepatocellular carcinoma (2.3%). Compared with sustained responders who did not develop hepatocellular carcinoma, patients who developed disease more often were male (P = 0.0212), were older (P = 0.0068), and had advanced-stage histologic disease before interferon therapy (P = 0.0345). Conversely, compared with patients with hepatocellular carcinoma who were not sustained responders, patients who were sustained responders tended to be older at the time of the initiation of interferon therapy (P = 0.0552) and at the time hepatocellular carcinoma was detected (P = 0.0593), and they also were predominantly male (P = 0.0507). The histologic staging and serum aminotransferase levels at the initiation of interferon therapy, the interval to the detection of tumor, and the tumor size showed no significant differences between the two groups. CONCLUSIONS: Sustained responders in the group at high risk for developing hepatocellular carcinoma after interferon therapy were older, more often were male, and had more advanced histologic disease stage. Such patients should be followed carefully periodically for > 10 years after they complete interferon therapy. 相似文献
99.
100.
Umemura T Kodama Y Kanki K Iatropoulos MJ Nishikawa A Hirose M Williams GM 《Toxicologic pathology》2003,31(1):10-13
Administration of diethylnitrosamine (DEN) to B6C3F1 mice at low dose (20 ppm) in drinking water for long duration resulted in formation of multifocal cystic biliary lesions in the liver. To investigate the potential of the lesions to be promoted to neoplasias by chemicals, we examined the effects of 2 different types of hepatocarcinogenesis promoters, pentachlorophenol (PCP) and phenobarbital (PB) in B6C3F1 mice. Two weeks' exposure to PCP at a concentration of 600 ppm in the diet increased 8-oxodeoxyguanosine (8-oxodG) levels in liver nuclear DNA, and cell proliferation quantified by bromodeoxyuridine (BrdU) incorporation in epithelial cells of intrahepatic bile ducts as well as hepatocytes. In mice initiated with DEN at 20 ppm in the drinking water for the first 13 weeks followed, after a 4-week recovery interval, by PCP at a concentration of 600 ppm in the diet for 25 weeks, cystic atypical hyperplasias, cholangiomas, and cholangiocarcinomas were present at statistically significant higher incidences. In contrast, neoplasia did not occur in animals treated with 500 ppm PB, and there were no elevations in 8-oxodG levels or increases in the proliferation of biliary epithelium, although proliferation was increased in hepatocytes. These findings suggest that oxidative stress due to PCP might exert a promoting action on the biliary cystic lesions produced by DEN. 相似文献