全文获取类型
收费全文 | 12516篇 |
免费 | 698篇 |
国内免费 | 59篇 |
专业分类
耳鼻咽喉 | 168篇 |
儿科学 | 325篇 |
妇产科学 | 116篇 |
基础医学 | 1582篇 |
口腔科学 | 286篇 |
临床医学 | 933篇 |
内科学 | 3366篇 |
皮肤病学 | 552篇 |
神经病学 | 932篇 |
特种医学 | 607篇 |
外科学 | 1989篇 |
综合类 | 50篇 |
一般理论 | 2篇 |
预防医学 | 240篇 |
眼科学 | 140篇 |
药学 | 901篇 |
中国医学 | 23篇 |
肿瘤学 | 1061篇 |
出版年
2023年 | 81篇 |
2022年 | 176篇 |
2021年 | 276篇 |
2020年 | 160篇 |
2019年 | 214篇 |
2018年 | 245篇 |
2017年 | 217篇 |
2016年 | 281篇 |
2015年 | 237篇 |
2014年 | 337篇 |
2013年 | 417篇 |
2012年 | 670篇 |
2011年 | 677篇 |
2010年 | 401篇 |
2009年 | 303篇 |
2008年 | 547篇 |
2007年 | 574篇 |
2006年 | 523篇 |
2005年 | 571篇 |
2004年 | 573篇 |
2003年 | 540篇 |
2002年 | 518篇 |
2001年 | 419篇 |
2000年 | 395篇 |
1999年 | 350篇 |
1998年 | 167篇 |
1997年 | 132篇 |
1996年 | 140篇 |
1995年 | 91篇 |
1994年 | 73篇 |
1993年 | 66篇 |
1992年 | 225篇 |
1991年 | 229篇 |
1990年 | 236篇 |
1989年 | 223篇 |
1988年 | 219篇 |
1987年 | 207篇 |
1986年 | 201篇 |
1985年 | 204篇 |
1984年 | 153篇 |
1983年 | 100篇 |
1982年 | 60篇 |
1981年 | 59篇 |
1979年 | 113篇 |
1978年 | 58篇 |
1972年 | 57篇 |
1971年 | 48篇 |
1970年 | 50篇 |
1969年 | 48篇 |
1968年 | 50篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Ota H Hayama M Nakayama J Hidaka H Honda T Ishii K Fukushima M Uehara T Kurihara M Ishihara K Hotta K Katsuyama T 《American journal of clinical pathology》2001,115(1):69-79
The specificity of monoclonal antibodies against gastric mucins (designated as HIK1083, PGM 36, and PGM 37) was studied immunohistochemically in normal, metaplastic, and neoplastic human tissues. These antibodies labeled class III mucin-producing cells identified by paradoxical concanavalin A staining in normal stomach, duodenum (Brunner gland), biliary tract, and main pancreatic duct; in mucinous metaplasia of pancreas and gallbladder; and in adenocarcinomas of stomach (90%), bile duct (80%), gallbladder (100%), pancreas (80%), lung (100% of goblet cell type adenocarcinomas), ovary (67% of mucinous carcinomas), and uterine cervix (100% of adenoma malignum tumors). Normal and neoplastic cells of esophagus, colon, salivary gland, kidney, endometrium, breast, prostate, and liver, as well as normal small intestine, lung, and uterine cervix, were all negative. The antibodies used should be valuable for the detection of class III mucin and class III mucin-producing cells in normal, metaplastic, and neoplastic tissues. 相似文献
102.
Kobayashi M Masuda Y Fujimoto Y Matsuya T Yamamura K Yamada Y Maeda N Morimoto T 《Physiology & behavior》2002,75(3):377-385
Although rhythmic jaw movement in feeding has been studied in mammals, such as rats, rabbits and monkeys, the cellular and molecular mechanisms underlying it are not well understood. Transgenic and gene-targeting technologies enable direct control of the genetic makeup of the mouse, and have led to the development of a new category of reagents that have the potential to elucidate the cellular and molecular mechanisms of neural networks. The present study attempts to characterize rhythmic jaw movements in the mouse and to demonstrate its relevance to rhythmic jaw movements found in higher mammals using newly developed jaw-tracking systems and electromyograms of the masticatory muscles. The masticatory sequence of the mouse during feeding was classified into two stages, incision and chewing. Small and rapid (8 Hz) open-close jaw movements were observed during incision, while large and slow (5 Hz) open-close jaw movements were observed during chewing. Integrated electromyograms of the masseteric and digastric muscles were larger during chewing than those observed during incision. Licking behavior was associated with regular (8 Hz), small open-close jaw movements with smaller masseteric activity than those observed during mastication. Grooming showed variable patterns of jaw movement and electromyograms depending on the grooming site. These results suggest that there are neuronal mechanisms producing different frequencies of rhythmic jaw movements in the mouse, and we conclude that the mouse is useful for understanding rhythmic jaw movements in higher mammals. 相似文献
103.
Chiba Y Saitoh N Matsuo K Misawa M 《International archives of allergy and immunology》2002,127(4):285-293
BACKGROUND: Nasal hyperresponsiveness is a common feature of allergic rhinitis, but the underlying mechanisms have yet to be elucidated. The effects of repeated antigen inhalation on the characteristics of histamine H(1) receptors and expression levels of heterotrimeric guanosine 5'-triphosphate-binding proteins in nasal mucosa were investigated to understand the mechanisms of the pathogenesis of nasal hyperresponsiveness in allergic rhinitis. METHODS: Male Hartley guinea pigs were sensitized by the inhalation of dinitrophenylated ovalbumin antigen (10 mg of protein/ml) and repeatedly challenged by inhaling aerosolized dinitrophenylated ovalbumin antigen for 3 weeks. Twenty-four hours after the last antigen inhalation, in vivo nasal responsiveness to histamine was measured. [(3)H]Mepyramine binding assays and immunoblotting for alpha subunits of the G(q) protein were also performed using membrane preparations of isolated nasal mucosae. RESULTS: The histamine-induced increase in intranasal pressure was significantly augmented after repeated antigen challenge, indicating that nasal hyperresponsiveness was achieved. In saturation binding studies, no significant change was observed in the density and antagonist affinity of H(1) receptors in the hyperresponsive animals. On the other hand, the affinity of histamine for high-affinity agonist binding sites in the hyperresponsive group, measured by histamine competition binding studies, was much greater than that in control animals, and these results were affected by guanosine 5'-O-(3-thiotriphosphate) in both groups. Moreover, Galpha(q) levels in nasal mucosal homogenates were significantly increased after repeated antigen challenge. CONCLUSIONS: Elevated G protein levels in nasal mucosa might induce an increased binding affinity of histamine to its receptors, resulting in an augmented nasal response to histamine, that is, nasal hyperresponsiveness, in guinea pigs. 相似文献
104.
Masumura K Kuniya K Kurobe T Fukuoka M Yatagai F Nohmi T 《Environmental and molecular mutagenesis》2002,40(3):207-215
Heavy-ion radiation accounts for the major component of absorbed cosmic radiation and is thus regarded as a significant risk during long-term manned space missions. To evaluate the genetic damage induced by heavy particle radiation, gpt delta transgenic mice were exposed to carbon particle irradiation and the induced mutations were compared with those induced by reference radiations, i.e., X-rays and gamma-rays. In the transgenic mouse model, deletions and point mutations were individually identified as Spi(-) and gpt mutations, respectively. Two days after 10 Gy of whole-body irradiation, the mutant frequencies (MFs) of Spi(-) and gpt were determined. Carbon particle irradiation significantly increased Spi(-) MF in the liver, spleen, and kidney but not in the testis, suggesting an organ-specific induction of mutations by heavy-ion irradiation. In the liver, the potency of inducing Spi(-) mutation was highest for carbon particles (3.3-fold increase) followed by X-rays (2.1-fold increase) and gamma-rays (1.3-fold increase), while the potency of inducing gpt mutations was highest for gamma-rays (3.3-fold increase) followed by X-rays (2.1-fold increase) and carbon particles (1.6-fold increase). DNA sequence analysis revealed that carbon particles induced deletions that were mainly more than 1,000 base pairs in size, whereas gamma-rays induced deletions of less than 100 base pairs and base substitutions. X-rays induced various-sized deletions and base substitutions. These results suggest that heavy-ion beam irradiation is effective at inducing deletions via DNA double-strand breaks but less effective than X-ray and gamma-ray irradiation at producing oxidative DNA damage by free radicals. 相似文献
105.
106.
Phosphorylation of cofilin by LIM-kinase is necessary for semaphorin 3A-induced growth cone collapse 总被引:12,自引:0,他引:12
Aizawa H Wakatsuki S Ishii A Moriyama K Sasaki Y Ohashi K Sekine-Aizawa Y Sehara-Fujisawa A Mizuno K Goshima Y Yahara I 《Nature neuroscience》2001,4(4):367-373
Semaphorin 3A is a chemorepulsive axonal guidance molecule that depolymerizes the actin cytoskeleton and collapses growth cones of dorsal root ganglia neurons. Here we investigate the role of LIM-kinase 1, which phosphorylates an actin-depolymerizing protein, cofilin, in semaphorin 3A-induced growth cone collapse. Semaphorin 3A induced phosphorylation and dephosphorylation of cofilin at growth cones sequentially. A synthetic cell-permeable peptide containing a cofilin phosphorylation site inhibited LIM-kinase in vitro and in vivo, and essentially suppressed semaphorin 3A-induced growth cone collapse. A dominant-negative LIM kinase, which could not be activated by PAK or ROCK, suppressed the collapsing activity of semaphorin 3A. Phosphorylation of cofilin by LIM-kinase may be a critical signaling event in growth cone collapse by semaphorin 3A. 相似文献
107.
Hiroshi Shuto Hisashi Noguchi Hikaru Nishikata Kenji Takizawa Chizuru Shuto Makoto Nagata Yoshinori Terashi Michiya Yamaguchi Takao Takizawa Kensuke Watanabe Kaoru Tosaka Masahiko Okano Akira Koizumi 《Arerugī》2007,56(7):714-720
In general, steroid is mainly used as anti-inflammatory action in case of allergic diseases. As one of the side effects of inhalation steroid, a report is given below regarding buccal capsule/esophageal candidiasis. The patient came to the hospital with the chief complaint regarding passage dysphagia in the time of deglutition; pharyngitis and esophageal candidiasis were found by endoscopy of upper gastrointestinal tract.The interview after the endoscopy revealed that the patient, a 69-year-old female was diagnosed as chronic perennial allergic rhinitis a few years ago, and had been inhaling rhinenchysis Beclometasone dipropionate (BDP) before sleep every day for the past two years because using this collunarium seemed to mitigate the nasal obstruction and mucus during sleep. The patient did not report this fact before the endocsopy because she did not associate it with her subjective symptom. In this case, it was assumed that nebulized rhinenchysis BDP was accidentally swallowed to the pharynx and esophagus during sleep. As a treatment, rhinenchysis BDP was canceled and instead Azunol mouth washing (gargling/nasal douche) was used. No antifungal agent was used. In two weeks, the patient reported some improvement, and this was confirmed by reexamination of the upper gastrointestinal tract using endoscope in one month and a half. Pharyngitis was improved, and in the digital endoscopic assessment of esophageal candidiasis complicating inhaled steroid therapy the esophageal candidiasis became Grade I (mild grade). As for the later progress, the patient did not report any subjective symptoms such as nasal obstruction and dysphagia. In addition, the inflammation caused by candidiasis and found in the early examination was improved. The patient in this case was under treatment for thrombosis in the vein of lower extremity, but no complications such as diabetes mellitus or immune deficiency syndrome were observed. DISCUSSION: Esophageal candidiasis by chronic administration of inhalation of steroid before sleep for asthmatic patients has been reported. However, there has not been a report of esophageal candidiasis by chronic administration of rhinenchysis steroid before sleep for patients with allergic rhinitis. Similarly, in the case of the use of steroid in the form of collunarium before sleep, steroid stayed in the esophagus via the transendothelial nasal cavity, and that seemed to cause, in the long run, to develop esophageal candidiasis. CONCLUSIONS: One of the implications of the above case is that collunarium can go down, even when it is nebulized in the nasal cavity, to the esophagus via the nasal cavity to buccal capsule. This suggests the necessity for preventative measures in the case of chronic administration of steroid as follows. A. Blowing of the nose just after the use of collunarium B. Daily rinsing (gargling and nasal douche). 相似文献
108.
109.
110.
Fujihiko Suzuki Akira Saito Kazuhisa Ishii Akihiko Yamamura Michio Matsumoto Masanobu Eguchi Masataka Tanno Kunio Mizuguchi Yoshinori Hosokawa Koichi Suda Sachiko Takase 《Medical molecular morphology》1996,29(1):48-51
A rare placental site trophoblastic tumor (PSTT) in a 39-year-old female was studied. This tumor, protruding into the uterine cavity, was histologically similar to tumors in previously reported cases of PSTT. Ultrastructurally, the characteristic finding was the presence of perinuclear filaments. Also, the tumor cells were strongly positive for hPL by immunohistochemical method. These findings suggest that this was a tumor caused by neoplastic proliferation of the extravillous intermediate trophoblast. 相似文献