全文获取类型
收费全文 | 6841篇 |
免费 | 322篇 |
国内免费 | 36篇 |
专业分类
耳鼻咽喉 | 107篇 |
儿科学 | 165篇 |
妇产科学 | 64篇 |
基础医学 | 908篇 |
口腔科学 | 101篇 |
临床医学 | 479篇 |
内科学 | 1778篇 |
皮肤病学 | 168篇 |
神经病学 | 640篇 |
特种医学 | 240篇 |
外科学 | 869篇 |
综合类 | 18篇 |
预防医学 | 290篇 |
眼科学 | 51篇 |
药学 | 591篇 |
中国医学 | 3篇 |
肿瘤学 | 727篇 |
出版年
2023年 | 33篇 |
2022年 | 54篇 |
2021年 | 93篇 |
2020年 | 66篇 |
2019年 | 92篇 |
2018年 | 111篇 |
2017年 | 96篇 |
2016年 | 103篇 |
2015年 | 101篇 |
2014年 | 124篇 |
2013年 | 165篇 |
2012年 | 301篇 |
2011年 | 290篇 |
2010年 | 148篇 |
2009年 | 135篇 |
2008年 | 276篇 |
2007年 | 279篇 |
2006年 | 318篇 |
2005年 | 303篇 |
2004年 | 315篇 |
2003年 | 293篇 |
2002年 | 334篇 |
2001年 | 278篇 |
2000年 | 291篇 |
1999年 | 318篇 |
1998年 | 104篇 |
1997年 | 90篇 |
1996年 | 95篇 |
1995年 | 82篇 |
1994年 | 79篇 |
1993年 | 55篇 |
1992年 | 177篇 |
1991年 | 178篇 |
1990年 | 140篇 |
1989年 | 155篇 |
1988年 | 180篇 |
1987年 | 137篇 |
1986年 | 123篇 |
1985年 | 122篇 |
1984年 | 74篇 |
1983年 | 45篇 |
1982年 | 30篇 |
1981年 | 29篇 |
1980年 | 21篇 |
1979年 | 59篇 |
1978年 | 45篇 |
1977年 | 28篇 |
1975年 | 32篇 |
1971年 | 21篇 |
1969年 | 24篇 |
排序方式: 共有7199条查询结果,搜索用时 31 毫秒
101.
Naoshi Kaneko Tatsuyuki Muratake Hideki Kuwabara Takanori Kurosaki Mitsuru Takei Tsuyuka Ohtsuki Tadao Arinami Shoji Tsuji Toshiyuki Someya 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2007,(6):735-742
We analyzed a large multiplex schizophrenia pedigree collected in mid-eastern Japan using 322 microsatellite markers distributed throughout the whole autosome. Under an autosomal-dominant inheritance model, the highest pairwise LOD score (LOD = 1.69) was found at 4q (D4S2431: theta = 0.0), and LOD scores at two other loci 3q (ATA34G06) and 8q (D8S1128) were 1.62 and 1.46, respectively. In multipoint analysis, LOD scores of the regions on 4q and 3q remained at a similar level; however, the LOD score of the region on 8q apparently decreased. Additional dense map analysis revealed haplotypes on 4q and 3q regions shared by affected individuals. On chromosome 4q, the haplotype spanning about 8 centiMorgans (cM) was shared by four of six genotyped individuals with schizophrenia and one affected individual whose haplotype was estimated. On 3q, the haplotype spanning about 20 cM was shared by five genotyped individuals with schizophrenia. We obtained two candidate regions of major susceptibility loci for schizophrenia on chromosomes 3q and 4q. 相似文献
102.
T Suganuma T Imai K Idaira S Konno H Hoshino A Okazawa M Adachi T Takahashi M Maeda A Tsuji 《Arerugī》1991,40(5):529-537
We examined the effect of AH 21-132, which has been reported to relax airway smooth muscle and inhibit platelet activating factor (PAF)-induced airway hyperreactivity, on ozone-induced airway hyperresponsiveness (AHR) with airway inflammation in dogs. Airway responsiveness (AR) to methacholine was measured by modified Astograph (7 Hz oscillation method) before and after ozone exposure, and the numbers of neutrophils in the peripheral blood and total cell counts, differential cell counts and TXB2 in BALF were measured before and after ozone exposure. Ozone exposure was carried out for 2 hr at an ozone level of 3.46 +/- 0.10 ppm (mean +/- SE). There was a significant increase in AR to methacholine after ozone exposure (p less than 0.01), and the numbers of neutrophils in the peripheral blood and the total cell and neutrophil counts in BALF increased significantly (p less than 0.05). Pretreatment with AH 21-132 at an oral dose of 20 mg/kg significantly prevented the ozone-induced AHR to methacholine (p less than 0.01), and also inhibited the increase of neutrophil counts in the peripheral blood, and the total cell counts and the neutrophil counts in BALF after ozone exposure. There was no significant change in the levels of TXB2 in BALF before and after ozone exposure. In dogs not exposed to ozone, AR to methacholine and respiratory resistance to methacholine significantly decreased after administration of AH 21-132 at an oral dose of 20 mg/kg (p less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
103.
Kyogi Ogoshi Tomoo Tajima Toshio Mitomi Kimiyoshi Tsuji 《Clinical & experimental metastasis》1996,14(3):277-281
We investigated the association between human leucocyte antigen (HLA) antigens and lymph node metastasis in 724 gastric cancer patients. Among patients who had poorly differentiated adenocarcinoma with or without HLA-DR4 antigen, lymph node metastasis was detected in 80.8 and 54.9%, respectively (relative risk (RR)=3.5, P = 0.0005, corrected P = 0.0285). It was more common in patients with a family history of cancer death (RR = 7.7). Among signet ring cell carcinoma patients with or without HLA-1152 antigen, lymph node metastasis was detected in 57.7 and 19.7%, respectively (RR =5.6, P=0.0001, corrected P=0.0086). It was more common in patients who were smokers (RR = 8.3). Our findings suggest that HLA-DR4 and HLA-1152 antigens are associated with lymph node metastasis in gastric cancer. 相似文献
104.
M Xu T Aiuchi K Nakaya H Arakawa M Maeda A Tsuji T Kato C Takeshige Y Nakamura 《Neuroscience letters》1990,118(2):205-207
Release of cholecystokinin-like immunoreactivity (CCK-LI) in the medial thalamus of conscious rats was measured by brain dialysis and enzyme immunoassay. Analgesia caused by low-frequency electric stimulation of the tibial muscle, the tsusanli acupuncture point, was judged by change of pain threshold due to the stimulation. Medical thalamic CCK-LI released was increased by peripheral electric stimulations of both the acupuncture point and the non-acupuncture point. Results suggest that CCK acts as a neurotransmitter in the medial thalamus, a part of the analgesia inhibitory system. 相似文献
105.
Genetic control in the susceptibility of germfree inbred mice to infection by Escherichia coli O115a,c:K(B).
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
We studied the susceptibility of five germfree inbred strains of mice to oral infection by murine pathogenic Escherichia coli O115a,c:K(B) (MPEC), the causative agent of mouse megaenteron. Although MPEC colonized all strains of mice at 10(9)/g of feces, the mouse strains could be divided into three groups according to their intestinal lesions. In CF1 and C3H/He mice, intestinal lesions were produced in the cecum and colon with hyperplasia of epithelial cells accompanied by severe inflammatory reactions and erosion. The lesions in NC and C57BL/6 mice were restricted to the tip of the cecum, and hyperplasia of epithelial cells was more severe in these mice than in CF1 or C3H/He mice. BALB/c mice had no lesions. Analysis of F1 hybrids of CF1, NC, and BALB/c mice and offsprings from backcrosses of F1 mice to parental strains showed that susceptibility to MPEC seemed to be controlled genetically by a single locus which may be related to the receptors on epithelial cells for MPEC adherence. However, the differences in lesions between CF1 and NC mice suggest that a combination of this locus and another locus to which it may be related regulates the hyperplasia of intestinal epithelial cells. 相似文献
106.
Exponential hyperbolic sine function fitting of heart rate response to constant load exercise 总被引:1,自引:0,他引:1
Mizuo J Nakatsu T Murakami T Kusachi S Tominaga Y Mashima K Uesugi T Ueda H Suezawa C Tsuji T 《The Japanese journal of physiology》2000,50(4):405-412
We attempted to fit heart rate (HR) changes induced by constant exercise loads of different intensities to an exponential hyperbolic sine curve by the least-squares method, and we compared the results with the fitting of the changes to exponential curves. Seven healthy male volunteers performed three different intensities of constant-load exercise on a bicycle ergometer. The exponential hyperbolic sine function adequately fitted the HR responses induced by all three different intensities of loads: low (30 W: correlation coefficient, r = 0.68 +/- 0.13, mean +/- SD), moderate (75 W: r = 0.93 +/- 0.07) and high (125 W: r = 0.97 +/- 0.02). The first-order exponential curve fitted only the moderate load response. Although the second-order exponential equation fitted the HR response for both the moderate and high loads, the equation did not fit the low-load response (r = 0.43 +/- 0.26). In low-load exercise, the sum of the power of the residuals for the exponential hyperbolic sine curve fitting was significantly smaller than that for the first- or second-order exponential curve fitting. In conclusion, the exponential hyperbolic sine function is useful for quantitative analyses of the HR response to exercise loads of various intensities. 相似文献
107.
An investigation has been carried out to study changes in shape on aging in plastic deformed Ag-Pd-Au-Cu alloys. The changes in shape were measured in order to establish a relationship to the aging heat treatments. Their microstructure was observed in order to clarify this phenomenon at the same time. They were also investigated quantitatively using a feature analysis system. The changes in shape were interpreted as the shrinkage in volume resulting from the formation of the ordered phase. They were smaller at aging temperatures below 673 K. The change in microstructure was different at aging temperature between 573 and 773 K. These phenomena were due to the following: First, nodules which nucleated at the grain boundaries would have grown into the grains well before the formation of the ordered phase, and second, the shrinkage in volume would have been of a different kind that the ordered phase. Therefore aging treatments should be carried out at low temperature in order to minimize the changes in shape. Also, nodular growth should be inhibited in order to maximize the hardening in Ag-rich alloys. 相似文献
108.
BACKGROUND: Eosinophils contribute to the pathogenesis of asthma and localize to the lung after allergen exposure by uncertain mechanisms. METHODS: We used intrabronchial instillation of allergen to model the interaction between inhaled allergen and the lung. We measured the number of peripheral blood leukocytes and the expression of VLA-4 (CD49d), Mac-1 (CD11b) and PSGL-1 (CD162) up to 4 h after instillation of allergen into a bronchus of eight atopic asthmatics. For controls, we instilled normal saline into a subset of the asthmatic subjects, and allergen into nonatopic, nonasthmatic subjects. RESULTS: There were changes of total leukocyte number, number of polymorphonuclear leukocytes, lymphocytes, monocytes and eosinophils in all three groups (atopic asthmatics instilled with allergen, atopic asthmatics instilled with saline, nonatopic nonasthmatic subjects instilled with allergen), which were likely related to bronchoscopy. However, the decrease of eosinophils was significant only in the atopic asthmatics instilled with allergen. The remaining eosinophils in the allergen challenged asthmatics were not activated as defined by cell density or change of expression of VLA-4, Mac-1 and PSGL-1. CONCLUSIONS: While eosinophils rapidly and specifically leave the circulation after allergen challenge of atopic asthmatics, the remaining circulating eosinophils are not activated. 相似文献
109.
110.
A novel Fc receptor for IgA and IgM is expressed on both hematopoietic and non-hematopoietic tissues
Sakamoto N Shibuya K Shimizu Y Yotsumoto K Miyabayashi T Sakano S Tsuji T Nakayama E Nakauchi H Shibuya A 《European journal of immunology》2001,31(5):1310-1316
By contrast to well-defined Fc gamma and Fc epsilon receptors, the structural and functional characteristics of Fc mu receptor are unclear. We have recently described a novel mouse Fc receptor, designated Fc alpha/mu receptor, and its human homologue, which bind both IgM and IgA. Here we show that the Fc alpha/mu receptor is expressed on mature, but not immature, B lymphocytes and acquires the ability to bind IgM and IgA antibodies after stimulation of B lymphocytes. Moreover, stimulation with phorbol 12-myristate 13-acetate increased endocytosis of IgM-coated microparticles mediated by the Fc alpha/mu receptor expressed on pro-B cell line Ba/F3 cells. We also show that the Fc alpha/mu receptor is expressed in secondary lymphoid organs, such as lymph node and appendix, kidney and intestine, suggesting an important role of the receptor for immunity in these organs. 相似文献