全文获取类型
收费全文 | 11610篇 |
免费 | 541篇 |
国内免费 | 37篇 |
专业分类
耳鼻咽喉 | 164篇 |
儿科学 | 153篇 |
妇产科学 | 146篇 |
基础医学 | 1611篇 |
口腔科学 | 431篇 |
临床医学 | 753篇 |
内科学 | 2798篇 |
皮肤病学 | 166篇 |
神经病学 | 803篇 |
特种医学 | 644篇 |
外科学 | 1753篇 |
综合类 | 68篇 |
一般理论 | 1篇 |
预防医学 | 451篇 |
眼科学 | 301篇 |
药学 | 825篇 |
中国医学 | 21篇 |
肿瘤学 | 1099篇 |
出版年
2023年 | 64篇 |
2022年 | 128篇 |
2021年 | 224篇 |
2020年 | 117篇 |
2019年 | 146篇 |
2018年 | 173篇 |
2017年 | 141篇 |
2016年 | 186篇 |
2015年 | 211篇 |
2014年 | 275篇 |
2013年 | 306篇 |
2012年 | 533篇 |
2011年 | 567篇 |
2010年 | 282篇 |
2009年 | 297篇 |
2008年 | 476篇 |
2007年 | 532篇 |
2006年 | 522篇 |
2005年 | 490篇 |
2004年 | 516篇 |
2003年 | 542篇 |
2002年 | 525篇 |
2001年 | 424篇 |
2000年 | 468篇 |
1999年 | 424篇 |
1998年 | 154篇 |
1997年 | 131篇 |
1996年 | 100篇 |
1995年 | 84篇 |
1994年 | 84篇 |
1993年 | 86篇 |
1992年 | 326篇 |
1991年 | 300篇 |
1990年 | 257篇 |
1989年 | 235篇 |
1988年 | 231篇 |
1987年 | 212篇 |
1986年 | 178篇 |
1985年 | 162篇 |
1984年 | 127篇 |
1983年 | 112篇 |
1979年 | 66篇 |
1978年 | 51篇 |
1977年 | 53篇 |
1975年 | 61篇 |
1973年 | 49篇 |
1972年 | 57篇 |
1971年 | 47篇 |
1968年 | 61篇 |
1967年 | 64篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
Murakami R Obara H Momota T Tanaka A Nakamura H Mikawa K Iwai S 《Journal of anesthesia》1989,3(2):149-154
Morphological alterations in the lungs of rats deficient in either or both of vitamin E and essential fatty acids were investigated after exposure to hyperoxia for 48h. In rats deficient in both vitamin E and essential fatty acids, there was damage to type-2 alveolar cells observed as swollen mitochondria and bleb formation in the cytoplasm. None of these changes was found in rats deficient in only one of these substances. Hyperoxia in rats deficient in both substance also caused destruction of the capillary endothelial cells and edema in the interstitium. The lungs of rats deficient in only one of the substances showed some edema in the capillary endothelial cells, but not destruction, and less interstitial edema. These findings suggest that simultaneous deficiency in vitamin E and essential fatty acids facilitates lung damage in rats exposed to hyperoxia.(Murakami R, Obara H, Momota T et al.: The effect of hyperoxia on the lungs of rats deficient in essential fatty acids. J Anesth 3: 149–154, 1989) 相似文献
52.
I Sano I Fujita H Tsuboi Y Murakami M Nagata T Yasui S Konishi H Akioka M Hayashi M Ohshima 《Rinsho byori. The Japanese journal of clinical pathology》1990,38(11):1238-1246
Although increasing attention is being given to Legionella pneumonia in Japan, reports of solitary onset of this disease are scant in Japan. The patient, from whom L. dumoffii was isolated, was a 59-year-old male with no underlying disease. He visited our hospital because of fever and cough, and was admitted to our department for X-ray findings consistent with pneumonia. After admission, pulmonary lesions spread rapidly, and based on the suspicion of Legionella pneumonia, drugs such as EM, RFP and MINO were used. However, the patient died on the 26th hospital day. L. dumoffii was isolated from specimens obtained by airway aspiration before death and specimens of lung abscess and airway discharge obtained during autopsy (7 specimens in total). In addition, the L. dumoffii antibody titer in the serum became elevated. This is the first case of L. dumoffii pneumonia reported in Japan. The other case was in an 81-year-old male with underlying disease. He was admitted urgently with suspected pneumonia but died on the following day. L. pneumophila serogroup 5 was isolated from autopsied lung tissue. Fatality is high for this disease, making early diagnosis and treatment with appropriate antibiotics essential. Physicians should bear in mind the possibility of this disease and request the necessary laboratory tests in suspected cases without delay. 相似文献
53.
H Yamashita S Noguchi N Murakami R Kato M Adachi S Inoue S Kato I Nakayama 《Acta pathologica japonica》1990,40(10):705-712
Effects of dietary iodine on the induction of thyroid carcinoma using N-nitrosobis(2-hydroxypropyl)amine (BHP) were studied. Male Wistar rats were fed with an iodine-adequate diet (IAD group), an iodine-rich diet (IRD group) and an iodine-deficient diet (IDD group), respectively, until the time of sacrifice. From the 2nd experimental month, animals were injected with BHP once a week for 10 weeks. In the IAD and IRD groups, benign nodules and papillary carcinoma were found. The incidence of rats with benign nodules was 100% in both groups and animals with papillary carcinoma in the IAD and IRD groups comprised 33% and 29%, respectively. The area of the thyroid gland occupied by nodular lesions was much narrower in the IRD group than in the IAD group. In the IDD group, the thyroid showed marked enlargement due to multiple nodular proliferation of follicle cells. The incidence of rats with carcinoma was 100%, and not only papillary but also follicular carcinoma and one pulmonary metastasis were found. As the iodine content of the diet decreased, the nodular lesions increased in width and number, and the incidence of carcinoma in rats became higher. These effects of dietary iodine are probably related to the goitrogenic and/or promoting effects of TSH. 相似文献
54.
HeLa cell invasiveness and O antigen of Shigella flexneri as separate and prerequisite attributes of virulence to evoke keratoconjunctivitis in guinea pigs. 总被引:9,自引:7,他引:9 下载免费PDF全文
N Okamura T Nagai R Nakaya S Kondo M Murakami K Hisatsune 《Infection and immunity》1983,39(2):505-513
Many rough mutants selected from isogenic smooth virulent and avirulent strains of Shigella flexneri were examined for virulence, using tissue culture infection and Sereny tests. Many of the rough mutants isolated from a virulent smooth strain were capable of penetrating tissue culture cells but incapable of producing a positive Sereny test. In contrast, we could not obtain from smooth avirulent strains any rough mutants capable of penetrating HeLa cells. Chemical analysis of lipopolysaccharide of some representative rough strains showed several patterns of sugar composition with a range of from Ra to Re chemotypes. There was no correlation between HeLa cell invasiveness and chemotypes of lipopolysaccharides, thus indicating little significance of oligosaccharides of the rough core as well as O antigens in the ability of S. flexneri to penetrate HeLa cells. When these invasive rough strains were given O antigen genes from a smooth avirulent Shigella Hfr strain, most of the transconjugants that expressed O antigens regained the ability to evoke keratoconjunctivitis in guinea pigs. We also examined the chromosomal loci of HeLa cell invasion by transferring carbohydrate fermentation genes of Escherichia coli K-12 Hfr and found two chromosomal loci, the rha and lac-gal regions, which control the ability to penetrate HeLa cells. These results suggested that O antigens and ability to penetrate tissue culture cells are independent and prerequisite attributes of virulence in Shigella flexneri to evoke keratoconjunctivitis in guinea pigs. 相似文献
55.
Effect of serum amyloid P component level on transthyretin-derived amyloid deposition in a transgenic mouse model of familial amyloidotic polyneuropathy. 下载免费PDF全文
T. Murakami S. Yi S. Maeda F. Tashiro K. Yamamura K. Takahashi K. Shimada S. Araki 《The American journal of pathology》1992,141(2):451-456
To elucidate the pathogenesis of amyloid deposition associated with familial amyloidotic polyneuropathy (FAP), we developed several transgenic mouse lines carrying the human mutant transthyretin (TTR) gene. We found that human TTR and mouse serum amyloid P component (SAP) are deposited as amyloid in tissues of these mouse lines. Because SAP is a major acute-phase reactant in mice, we asked whether repeated injections of Escherichia coli lipopolysaccharide (LPS) would enhance the amyloid deposition in one of these transgenic mouse lines. During the course of repeated LPS injections, serum levels of SAP in the transgenic mice remained between severalfold to about 50-fold higher than seen in the absence of stimulation. As no significant difference was detected in the onset, progression, and tissue distribution of TTR-derived amyloid (ATTR) deposition between the LPS-stimulated and unstimulated transgenic mice, the induction of SAP synthesis by acute inflammation probably does not affect the onset and extent of ATTR deposition. 相似文献
56.
Social isolation stress augments angiogenesis induced by colon 26-L5 carcinoma cells in mice 总被引:3,自引:0,他引:3
Wu W Murata J Murakami K Yamaura T Hayashi K Saiki I 《Clinical & experimental metastasis》2000,18(1):1-10
We have previously shown that tumor necrosis factor-α (TNF-α), which is an important angiogenesis-related factor, was over-secreted in male BALB/c mice under social isolation stress as compared with the control, and closely associated with a remarkable elevation of tumor invasion and metastasis of colon 26-L5 carcinoma cells. In the present study, we explored the effect of isolation stress on the angiogenesis caused by colon 26-L5 carcinoma cells in vivo and in vitro. Social isolation lead to the enhancement of tumor growth after intrahepatic implantation with a fragment of colon 26-L5 tumor. Angiogenic response (number of vessels oriented towards tumor mass) and tumor growth (size) were significantly increased in the socially isolated mouse relative to that in the group-housed mice. Furthermore, higher protein level of hepatic TNF-α was found in the stressed mice than that in the control. Expression of mRNA for vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF) were also elevated in the tumor regions and liver tissues of the stressed mice in comparison with that in group-housed mice. On the other hand, hepatic sinusoidal endothelial (HSE) cells treated with TNF-α exhibited a marked promotion of the migration, invasion, expression of mRNA for matrix metalloproteinase (MMP)-9, and tube-like formation, but no cytotoxicity against the cells in vitro. The above data suggest that the social isolation stress augmented the tumor-induced angiogenesis probably by up-regulating the angiogenesis-related factors, including TNF-α, VEGF and HGF, and consequently mediating the functions of endothelial cells such as migration, invasion, and tube-like formation. 相似文献
57.
Endomyometriosis arising in the uterosacral ligament: a case report including a literature review and immunohistochemical analysis 总被引:2,自引:0,他引:2
Matsuzaki S Murakami T Sato S Moriya T Sasano H Yajima A 《Pathology international》2000,50(6):493-496
We report a case of endomyometriosis arising in the left uterosacral ligament of a 29-year-old woman. The central cavity of the uterine-like mass was lined by pseudo-stratified columnar epithelium and endometrial stroma. The wall of the cyst consisted of bundles of smooth muscle cells. Immunohistochemical analysis demonstrated both alpha-estrogen receptor and progesterone receptor immunoreactivities in the epithelial, stromal and smooth muscle cells. A relatively high proliferating activity was also demonstrated in these cells by Ki-67 immunostaining. These findings suggest that the mass was hormone dependent and had a relatively rapid evolution. 相似文献
58.
59.
J. W. Said G. Nash S. Banks-Schlegel A. F. Sassoon S. Murakami I. P. Shintaku 《The American journal of pathology》1983,113(1):27-32
In this immunohistochemical study, antiserums to different molecular weight keratin proteins (45kd, 46kd, 55kd, and 63kd) were utilized to determine the profiles of keratin proteins present in a variety of pulmonary neoplasms. Different histologic types of lung carcinoma exhibited different patterns of keratin staining. Squamous cell carcinomas stained strongly for 45K, 46K, and 55K keratin, with staining for 63K restricted to areas or individual cells with cytoplasmic keratinization. Adenocarcinomas showed variable, generally weak staining for 45K, 46K, and 55K keratin and were uniformly negative for 63K keratin both in frozen and paraffin sections. Mesotheliomas and reactive mesothelial cells, by contrast, stained positively for 63K keratin in addition to keratins of lower molecular weights. Differences in staining for 63K keratin between mesothelioma and adenocarcinoma may have diagnostic application. Moreover, individual cytokeratins may serve as markers of tumor differentiation and provide information as to the origin of neoplastic cells. 相似文献
60.
After cold acclimation of rats the augmentation of succinic dehydrogenase activity in the fast-twitch oxidative glycolytic (FOG) and the slow-twitch oxidative (SO) fibers was observed in entire regions of the soleus, the extensor digitorum longus, the plantaris, the longissimus and the gastrocnemius muscles. Furthermore, a tendency to increased proportion of the FOG and the SO fibers was observed more prominently in superficial regions than in deep regions of a large muscle such as the gastrocnemius muscle. 相似文献