全文获取类型
收费全文 | 14931篇 |
免费 | 774篇 |
国内免费 | 95篇 |
专业分类
耳鼻咽喉 | 273篇 |
儿科学 | 335篇 |
妇产科学 | 393篇 |
基础医学 | 1947篇 |
口腔科学 | 340篇 |
临床医学 | 1408篇 |
内科学 | 3060篇 |
皮肤病学 | 566篇 |
神经病学 | 906篇 |
特种医学 | 682篇 |
外科学 | 2458篇 |
综合类 | 160篇 |
现状与发展 | 1篇 |
一般理论 | 2篇 |
预防医学 | 615篇 |
眼科学 | 335篇 |
药学 | 1159篇 |
中国医学 | 152篇 |
肿瘤学 | 1008篇 |
出版年
2023年 | 97篇 |
2022年 | 258篇 |
2021年 | 436篇 |
2020年 | 206篇 |
2019年 | 287篇 |
2018年 | 430篇 |
2017年 | 310篇 |
2016年 | 365篇 |
2015年 | 453篇 |
2014年 | 663篇 |
2013年 | 681篇 |
2012年 | 1077篇 |
2011年 | 1072篇 |
2010年 | 638篇 |
2009年 | 513篇 |
2008年 | 854篇 |
2007年 | 836篇 |
2006年 | 779篇 |
2005年 | 786篇 |
2004年 | 697篇 |
2003年 | 565篇 |
2002年 | 553篇 |
2001年 | 468篇 |
2000年 | 441篇 |
1999年 | 355篇 |
1998年 | 132篇 |
1997年 | 95篇 |
1996年 | 100篇 |
1995年 | 80篇 |
1994年 | 65篇 |
1993年 | 38篇 |
1992年 | 154篇 |
1991年 | 120篇 |
1990年 | 129篇 |
1989年 | 86篇 |
1988年 | 93篇 |
1987年 | 107篇 |
1986年 | 72篇 |
1985年 | 73篇 |
1984年 | 43篇 |
1983年 | 31篇 |
1979年 | 53篇 |
1977年 | 42篇 |
1976年 | 35篇 |
1975年 | 33篇 |
1974年 | 39篇 |
1973年 | 37篇 |
1972年 | 39篇 |
1970年 | 28篇 |
1969年 | 29篇 |
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
91.
Characterization of Immunodominant Linear B-Cell Epitopes on the Carboxy Terminus of the Rinderpest Virus Nucleocapsid Protein 下载免费PDF全文
Kang-Seuk Choi Jin-Ju Nah Young-Joon Ko Shien-Young Kang Kyoung-Jin Yoon Yi-Seok Joo 《Clinical and Vaccine Immunology : CVI》2004,11(4):658-664
The nucleocapsid (N) protein of rinderpest virus (RPV) is one of the most abundant and immunogenic viral proteins expressed during natural or experimental infection. To identify immunogenic epitopes on the N protein, different forms of RPV N protein, including the full-length protein (N1-525), an amino-terminal construct (N1-179), and a carboxy-terminal construct (N414-496), were expressed in Escherichia coli as glutathione S-transferase (GST) fusion proteins. The antigenicity of each recombinant protein was evaluated by Western immunoblotting. All recombinants were recognized by hyperimmune RPV bovine antisera, indicating that immunoreactive epitopes may be present at both ends of the N protein. However, GST-N414-496 was much more antigenic than GST-N1-179 when tested with sera from vaccinated cattle, suggesting that an immunodominant or highly immunogenic epitope(s) may be located at the carboxy terminus of the N protein. Epitope mapping with overlapping peptides representing different regions of the carboxy terminus (amino acids 415 to 524) revealed three nonoverlapping antigenic sites in regions containing the residues 440VPQVRKETRASSR452 (site 1), 479PEADTDPL486 (site 2), and 520DKDLL524 (site 3). Among these, antigenic site 2 showed the strongest reactivity with hyperimmune anti-RPV bovine sera in a peptide enzyme-linked immunosorbent assay but did not react with hyperimmune caprine sera raised against peste-des-petits-ruminants virus, which is antigenically closely related to RPV. Identification of an immunodominant linear antigenic site at the carboxy terminus of the N protein may provide an antigen basis for designing diagnostics specific for RPV. 相似文献
92.
Kazuo Nagashima Hisako Endo Koko Sakakibara Yumiko Konishi Ko Miyachi Jau Jinn Wey Yoshiyuki Suzuki Jinichi Onisawa 《Pathology international》1976,26(1):115-132
An autopsy case of a 19-year-old boy who had shown typical gargoyle features, strictly consistent with mucopolysaccharidosis type II (Hunter's syndrome) was reported. Histologically, cytoplasmic vacuolar change was found In hepatocytes, sinusoidal epithelium of spleen, follicular cells of thyroid, Sertoli cells of testis, chromophobe cell of pituitary and generalized fibroblast-like cells including meninges, cardiac valve and periosteum. The vacuoles consisting of membrane-bound structures with flocculus protein-like material and occasional electron dense bodies on electron microscopy, were considered to be the site of mucopolysaccharide deposition by histochemical analysis. Deposition of lipid material consistent with so-called membranous cytoplasmic body was observed in the neurons of central, peripheral and autonomic nervous system. Hepatosplenomegaly could be explained by cytoplasmic deposition, but the cause of cardiomegaly remained further to be studied. Biochemically hepatic mucopolysaccharide was identified as heparan sulfate, while in the kidney dermatan sulfate and heparan sulfate were detected. The correlation between morphology and biochemistry, and between deposition and degeneration was discussed. 相似文献
93.
Metastatic tumors in the sellar and parasellar regions: clinical review of four cases 总被引:1,自引:0,他引:1
Metastatic tumors in the sellar and parasellar regions are uncommon and rarely detected in clinical practice. We present four cases of sellar and parasellar metastatic tumors, which metastasized from distant organ in one case and extended directly from adjacent structures in three. Common presenting symptoms were cranial neuropathies, headache and facial pain. Invasion into the cavernous sinus was noted in all cases. We report rare cases of sellar and parasellar metastases. Also, we should consider the possibility of metastasis in these regions for patients who showed the above clinical presentations in systemic cancer patients. In extensive diseases, transient symptomatic relief could be obtained by direct surgical management, even in restricted degree. 相似文献
94.
95.
A rare benign condition of uncertain etiology and pathogenesis, Synovial Chondromatosis (SC) is most often seen intraarticularly in adults but only a handful of cases have been reported extraarticularly in children. Symptoms and physical signs consist of pain, swelling, and osteoarthritic changes related to a mass effect. Here we discuss the case of a 9-year-old boy with documented SC of the knee and critically review the Epidemiology, Clinical Presentation, Gross Anatomy and Microscopic Histopathologic Features as well as the role of Imaging Studies in Diagnosis. In addition, this paper reviews Current Pathogenetic Concepts including the infrequent but distinct possibility of malignant transformation. 相似文献
96.
Sönmez AS Yasar L Savan K Koç S Ozcan J Toklar A Yazicioğu F Akgün A Sut N 《Human reproduction (Oxford, England)》2005,20(1):175-179
BACKGROUND: The aim of this study was to evaluate the effects of metformin and acarbose on insulin resistance, hormone profiles and ovulation rates in patients with clomiphene citrate-resistant polycystic ovary syndrome (PCOS). METHODS: Thirty clomiphene citrate-resistant patients were selected randomly and divided into two groups. Group I was treated with 100 mg/day clomiphene citrate and 300 mg/day acarbose 100 mg/day orally, for 3 months. Group II was treated with clomiphene citrate 100 mg/day and metformin 1700 mg/day orally, for 3 months. Serum fasting insulin and glucose, FSH, LH, estradiol, progesterone, prolactin and total testosterone levels plus body mass index (BMI) were measured before and after treatment. Follicle growth was followed by transvaginal ultrasonography. RESULTS: LH:FSH ratio and total testosterone concentrations decreased (P<0.05) and ovulation rates increased in both groups. Reduction in weight and BMI was only significant in the acarbose group. CONCLUSIONS: Both treatment modalities were effective in the treatment of insulin resistance and improving ovulation rates. Increase in the number of eumenorrhoeic and normoinsulinaemic cases and decrease in the number of insulin-resistant cases were significant in both groups (P<0.05). Ovulation rate was greater in the metformin group in the second month of therapy (P<0.05). Acarbose was found to be a safe and effective agent that could be used in cases with clomiphene-resistant PCOS. 相似文献
97.
Somatic mosaicism for a MECP2 mutation associated with classic Rett syndrome in a boy 总被引:4,自引:0,他引:4
Topçu M Akyerli C Sayi A Törüner GA Koçoğlu SR Cimbiş M Ozçelik T 《European journal of human genetics : EJHG》2002,10(1):77-81
Rett syndrome is a severe neurodevelopmental disorder that arises from mutations in the X-linked MECP2 gene. It is almost exclusively seen in girls due to the predominant occurrence of the mutations on the paternal X-chromosome, and also the early postnatal lethal effect of the disease causing mutations in hemizygous boys. We identified a boy with features of classic Rett syndrome who is mosaic for the truncating MECP2 mutation R270X. Chromosome analysis showed normal karyotype. These results indicate that a MECP2 mutation associated with Rett syndrome in females could lead to a similar phenotype in males as a result of somatic mosaicism. 相似文献
98.
Preferential expression of T(h)2-type chemokine and its receptor in atopic dermatitis 总被引:1,自引:0,他引:1
Lesional skin of patients with atopic dermatitis (AD) is histologically characterized by hypertrophy of the skin, and the infiltration of a large number of eosinophils and T cells into the dermis. Recent studies have indicated that Th2 cells play a crucial role in the pathogenesis of AD skin. Chemokines and their receptors are implicated in the development of symptoms of various skin diseases such as AD and psoriasis vulgaris (psoriasis). We have examined the in situ expression of a typical Th2-type chemokine, thymus- and activation-regulated chemokine (TARC), and its receptor (CCR4) using immunohistochemical techniques. TARC was found to be highly expressed in the basal epidermis of the lesional skin of AD patients and only slightly in the non-lesional skin. On the other hand, no positive cells were seen in the lesional skin of psoriasis. Consistently, CCR4+ cells were present predominantly in the lesional skin of AD patients, but not in the non-lesional skin. In contrast, in the lesional skin of psoriasis patients, cells positive for CCR5, which is expressed on Th1 cells, were abundantly present. Interestingly, psoralen plus ultraviolet A therapy reduced the number of CCR4+ cells in the AD skin lesions. These results suggest that Th2-type cytokines such as TARC are involved in the pathogenesis of skin lesions in AD patients through the preferential recruitment of Th2 cells. 相似文献
99.
Hsu SC Lin HP Wu JC Ko KL Sheen IJ Yan BS Chou CK Syu WJ 《Journal of virological methods》2000,87(1-2):53-62
Sequences of the hepatitis delta virus (HDV) vary to different degrees among isolates. A monoclonal antibody, designated as HP6A1, against the antigen of HDV (HDAg) has been characterized for its specificity. HP6A1 bound to HDAg of isolate 25 (genotype I) that was used for immunization, but not to others of both genotypes I and II. The epitope recognized by HP6A1 was then determined by a phage library displaying various heptapeptides. A consensus peptide deduced has the best match with that of residues 4-10 of HDAg (isolate 25). To confirm the phage mapping result, Escherichia coli recombinant proteins containing different lengths and various segments of HDAg (isolate 25) were constructed. The shortest HDAg segment contained in the fusion protein that reacted with HP6A1 was residues 1-10. When this peptide was added to the N-terminus of a heterologous protein engineered for eucaryotic expression, the fusion protein was detected by HP6A1. It is concluded that HP6A1 recognizes an epitope located at the N-terminus of HDAg (isolate 25). Since viruses of quasi-species exist in natural infections, a question of how different viral strains interact in vivo remains to be explored. The highly specific MAb opens a possibility to examine the fate of one strain in the presence of other related species in a cell transfection system. 相似文献
100.
M. Flesch A. Sachinidis Y. D. Ko K. Kraft H. Vetter 《Journal of molecular medicine (Berlin, Germany)》1994,72(12):944-950
In recent years there have been many studies demonstrating a correlation between increased arterial blood pressure and altered lipid profiles, and there has been an especially positive correlation between high cholesterol levels and blood pressure. There are differences between the various reports that are important. In our study the lipid distribution in 105 hypertensive patients with mild or moderate arterial hypertension according to WHO criteria without clinically or ultrasonographically apparent atherosclerosis was compared to the lipid distribution in 65 age-matched healthy persons. On the epidemiological level a significant, positive association was found between LDL serum levels (P 0.001), Apo B serum levels (P 0.001), serum triglyceride levels (P 0.05) and VLDL serum levels (P 0.01) and arterial hypertension. However, in contrast to recent reports, no significant difference was found between total serum cholesterol levels in normotensives and hypertensives, and there was no difference in HDL serum levels. No evidence could be found for a significant increase in lipoprotein (a) serum levels in hypertensives.Abbreviations LDL
low density lipoprotein
- VLDL
very low density lipoprotein
- HDL
high density lipoprotein
- Apo B 100
apolipoprotein B 100
- Apo A I
apolipoprotein A I
Correspondence to: H. Vetter 相似文献