全文获取类型
收费全文 | 4747篇 |
免费 | 187篇 |
国内免费 | 34篇 |
专业分类
耳鼻咽喉 | 53篇 |
儿科学 | 46篇 |
妇产科学 | 38篇 |
基础医学 | 497篇 |
口腔科学 | 103篇 |
临床医学 | 220篇 |
内科学 | 1282篇 |
皮肤病学 | 103篇 |
神经病学 | 477篇 |
特种医学 | 251篇 |
外科学 | 899篇 |
综合类 | 15篇 |
预防医学 | 93篇 |
眼科学 | 50篇 |
药学 | 245篇 |
中国医学 | 7篇 |
肿瘤学 | 589篇 |
出版年
2023年 | 27篇 |
2022年 | 73篇 |
2021年 | 113篇 |
2020年 | 52篇 |
2019年 | 64篇 |
2018年 | 96篇 |
2017年 | 60篇 |
2016年 | 98篇 |
2015年 | 84篇 |
2014年 | 164篇 |
2013年 | 172篇 |
2012年 | 267篇 |
2011年 | 287篇 |
2010年 | 211篇 |
2009年 | 162篇 |
2008年 | 257篇 |
2007年 | 298篇 |
2006年 | 291篇 |
2005年 | 290篇 |
2004年 | 311篇 |
2003年 | 312篇 |
2002年 | 306篇 |
2001年 | 60篇 |
2000年 | 53篇 |
1999年 | 71篇 |
1998年 | 78篇 |
1997年 | 79篇 |
1996年 | 82篇 |
1995年 | 50篇 |
1994年 | 53篇 |
1993年 | 31篇 |
1992年 | 45篇 |
1991年 | 25篇 |
1990年 | 31篇 |
1989年 | 32篇 |
1988年 | 41篇 |
1987年 | 36篇 |
1986年 | 20篇 |
1985年 | 20篇 |
1984年 | 12篇 |
1983年 | 16篇 |
1982年 | 16篇 |
1980年 | 10篇 |
1979年 | 19篇 |
1977年 | 11篇 |
1976年 | 10篇 |
1975年 | 9篇 |
1974年 | 11篇 |
1971年 | 8篇 |
1968年 | 7篇 |
排序方式: 共有4968条查询结果,搜索用时 15 毫秒
1.
2.
3.
Mitsuhiro Tozaki Kunihiko Fukuda Masafumi Suzuki 《Magnetic resonance in medical sciences》2006,5(3):137-146
PURPOSE: The purpose of this study was to assess the relationship between the amount of scirrhous component in invasive ductal carcinoma and its MR characteristics. MATERIALS AND METHODS: We retrospectively reviewed 71 consecutive patients with invasive ductal carcinoma smaller than 25 mm (average, 16.6 mm) in diameter. The scirrhous component was defined as invasive foci in small clusters of cancer cells showing desmoplasia. Invasive ductal carcinoma was subclassified into 3 groups in accordance with the amount of the scirrhous component (scirrhous component degree; SCD): SCD I (scirrhous component less than 20%), SCD II (intermediate), and SCD III (more than 80%). Dynamic magnetic resonance (MR) imaging was performed using volumetric interpolated sequence. Prior to dynamic study, T2*-weighted first-pass perfusion images were obtained before, during, and after bolus injection of 0.1 mmol Gd-DTPA/kg. RESULTS: Twenty-eight lesions were classified as SCD I, 14 as SCD II, and 29 as SCD III. Mass margin and signal intensity loss in the perfusion study were significantly different among the 3 SCD groups (P<0.001). The kinetic patterns were significantly different among the 3 SCD groups (P=0.04), and between SCD I/II and SCD III (P=0.03). The presence of enhancing internal septations was significantly different between SCD I/II and SCD III carcinomas (P=0.05). Central enhancement was only observed in SCD I carcinoma (4%; 3/71). CONCLUSION: The histological predominance of the scirrhous component in invasive ductal carcinoma may be one explanation for the differences in morphologic and kinetic patterns on MR imaging. 相似文献
4.
Active production of anti-human T-lymphotropic virus type I (HTLV-I) IgM antibody in HTLV-I-associated myelopathy 总被引:2,自引:0,他引:2
Kunihiko Nagasato Tatsufumi Nakamura Ohishi Kiyosumi Kohji Shibayama Masakatsu Motomura Ichinose Katsuhiro Mitsuhiro Tsujihata Shigenobu Nagataki 《Journal of neuroimmunology》1991,32(2):105-109
We investigated the presence of anti-human T-lymphotropic virus type I (HTLV-I) IgM in sera and cerebrospinal fluid from patients with HTLV-I-associated myelopathy (HAM) by Western blot analysis. Analyses of 36 serum samples revealed that most patients (31/36; 86.1%) had anti-HTLV-I IgM, whereas only four of 23 (17.4%) HTLV-I carriers had it. In studies of cerebrospinal fluid, anti-HTLV-I IgM was detected in 24 of 36 (66.7%) HAM patients, whereas none was detected in nine HTLV-I carriers. The differences were statistically significant (p less than 0.01). These results suggest that persistent active replication of HTLV-I occurs in the central nervous system as well as in the peripheral blood of HAM patients, and may contribute to the development of HAM. 相似文献
5.
T Iino N Toyosaki T Katsuki T Noda T Natsume T Yaginuma S Hosoda M Furuse 《Clinical nuclear medicine》1987,12(9):688-693
The perfusion territories in polar representations of stress Tl-201 rotational myocardial imaging in patients with angina pectoris who had one diseased coronary segment were analyzed. The lesions proximal or distal to the first major septal perforator in left anterior descending arteries were detected by the presence or absence of defects at the base of the anterior septum. Right coronary artery lesions were detected by the presence of defects at the basal posterior septum, in contrast to the preservation of myocardial uptake at this portion in lesions of the left circumflex artery. The specific defect patterns were detected in cases with lesions at the first diagonal, obtuse marginal, and posterolateral branches. Recognition of these defects in the polar maps allows detailed detection of diseased coronary arterial branches. 相似文献
6.
Yukinobu Nakaseko Kentaro Nabeshima Kazuhisa Kinoshita & Mitsuhiro Yanagida 《Genes to cells : devoted to molecular & cellular mechanisms》1996,1(7):633-644
Background : Fission yeast microtubule associating protein (MAP) p93Dis1 functions for sister chromatid separation: dis1 mutants fail to separate chromosomes, while the spindle elongates but without cyclin destruction. p93Dis1 localizes along microtubules in interphase cytoplasm, but shifts to the spindle pole body (SPB) and spindle microtubules upon the entry into mitosis. In this study, regions of p93Dis1 were dissected to examine their role.
Results : Nitrocellulose filter blotting shows that recombinant Dis1 binds to bovine brain microtubules in vitro . A basic central region rich in S, T and P is essential for this association. However, the whole p93Dis1 with N- and C-termini containing a conserved repeat motif and heptad repeats, respectively, is necessary for normal microtubule association in vivo . The N-truncated region also binds to microtubules but only to the portions near the SPBs. Overproduction phenotypes indicate that p93Dis1 greatly affects spindle formation and cell morphogenesis. The central region is essential but, by itself, not sufficient for generating such effects.
Conclusions : We propose that p93Dis1 consists of three regions which carry distinct properties for localization: the N-region for cell cycle dependent localization, the central region for direct microtubule association, and the C-region for SPB and nuclear localization. The essential role of p93Dis1 is carried out in the C-region, while the N-region acts as a regulator. 相似文献
Results : Nitrocellulose filter blotting shows that recombinant Dis1 binds to bovine brain microtubules in vitro . A basic central region rich in S, T and P is essential for this association. However, the whole p93
Conclusions : We propose that p93
7.
Satomi-Kobayashi Seimi Kawashima Seinosuke Sakoda Tsuyoshi Ueyama Tomomi Hirase Tetsuaki Kawai Miki Toh Ryuji Iwai Kenji Yokoyama Mitsuhiro 《Circulation journal》2004,68(3):247-253
BACKGROUND: Glycogen synthase kinase-3 beta (GSK-3beta) is involved in many cellular processes, such as metabolism, apoptosis, differentiation and proliferation. Insulin-like growth factor-1 (IGF-1), which is well known to have a hypertrophic effect on cardiomyocytes, inactivates (phosphorylates) GSK-3beta in some cell types. The role of GSK-3beta in cardiomyocytes as a negative regulator of cardiac hypertrophy has been recently reported and the present study investigated the role of GSK-3beta in the cardiac hypertrophy of cultivated neonatal rat cardiomyocytes induced by IGF-1. METHODS AND RESULTS: First, the IGF-1 induced signal transduction leading to GSK-3beta in neonatal rat cardiomyocytes was examined. The phosphatidylinositol (PI) 3-kinase/Akt/GSK-3 beta signaling induced by IGF-1 was investigated using inhibitors of PI 3-kinase and Ad AktAA, a dominant negative form of Akt. Furthermore, using Ad MEK DN, a dominant negative form of MEK, it was found that MEK negatively regulates Akt phosphorylation upon IGF-1 stimulation. Next, it was examined whether GSK-3beta acts as a negative regulator in the cardiac hypertrophy induced by IGF-1. Sustained stimulation by IGF-1 caused cardiac hypertrophy in protein synthesis and cellular morphology, and overexpression of unphosphorylatable GSK-3beta (Ad GSK-3beta S9A) repressed these hypertrophic effects of IGF-1. CONCLUSIONS: GSK-3beta may play an important role as a negative regulator of cardiac hypertrophy induced by IGF-1. 相似文献
8.
Jong Il Kim Takeshi Tsujino Yoshio Fujioka Komei Saito Mitsuhiro Yokoyama 《Hypertension research》2003,26(4):307-313
We examined cellular membrane fatty acid composition and insulin sensitivity in patients with mild essential hypertension and hyperlipidemia, and investigated whether bezafibrate, a lipid-lowering drug, could improve elevated blood pressure and insulin sensitivity in these subjects by ameliorating cellular membrane fatty acid composition. Twenty-seven subjects were recruited. Twelve men with mild essential hypertension [systolic blood pressure (SBP) between 140 mmHg and 160 mmHg] and hypertriglyceridemia (plasma triglyceride concentration over 150 mg/dl) were designated the HL group. Fifteen men with mild essential hypertension and normotriglyceridemia (plasma triglyceride concentration below 150 mg/dl) were designated the NL group. Subjects in the HL group were given bezafibrate 400 mg/dl and those in the NL group were given placebo for 3 months. Bezafibrate significantly reduced SBP (140 +/- 2.6 to 131.8 +/- 2.6 mmHg, mean +/- SEM), diastolic blood pressure (DBP) (87.8 +/- 2.0 to 82.8 +/- 2.6 mmHg), fasting plasma triglyceride concentration (225.5 +/- 23.5 to 102.9 +/- 10.9 mg/dl), fasting plasma insulin concentration (9.6 +/- 0.8 to 7.1 +/- 0.8 microU/ml), and homeostasis model assessment scores (HOMA-R, 2.4 +/- 0.2 to 1.7 +/- 0.2), and significantly improved the insulin sensitivity index (56.0 +/- 3.0 to 70.7 +/- 4.8 mg x l2/mmol x mU x min) in the HL group. Regarding erythrocyte membrane fatty acid composition, bezafibrate reduced the percentages of saturated fatty acids (SFA) and increased the percentage of polyunsaturated fatty acids (PUFA). Plasma triglyceride concentrations were positively correlated with HOMA-R (r = 0.50, p < 0.01) and SFA (r = 0.39, p < 0.05), and negatively correlated with PUFA (r = -0.45, p < 0.05) before administration of placebo or bezafibrate. In conclusion, an improvement of hyperlipidemia by bezafibrate may be attributed to reduction of blood pressure and amelioration of insulin sensitivity. Abnormalities in membrane lipid composition may play an important role in these metabolic disorders. 相似文献
9.
Nobutaka Eiraku Shinji Ijichi Shinji Yashiki Mitsuhiro Osame Shunro Sonoda 《Journal of neuroimmunology》1992,37(3):223-228
The in vitro proliferation of peripheral blood lymphocytes (PBLs) without any mitogenic stimulation is one of the hallmarks of human T lymphotropic virus type I (HTLV-I) infection. Recent evidence suggests a difference in the degree of the phenomenon between HTLV-I-associated myelopathy/tropical spastic paraparesis (HAM/TSP) and asymptomatic HTLV-I carriers (AC). In this article, we demonstrated several alterations in the features of the in vitro transformed lymphocytes between patients with HAM/TSP (n = 16) and AC (n = 8). The percentages of total CD8+ and CD8+CD28+ cells were significantly increased in the in vitro proliferating T lymphocytes derived from the patients with HAM/TSP when compared to those from AC. HAM/TSP was segregated from AC by the high degree of the proliferation of CD8+CD28+ cells. The expression of HTLV-I-specific antigens on the cultured PBLs was detected only in the subjects which showed low CD8+CD28+/CD4+ ratio of the in vitro proliferating lymphocytes. These findings suggest that this phenomenon distinguishes HAM/TSP from AC, not only in quantity but also in quality. 相似文献
10.
Invasion of the skull base by carcinomas: histopathologically evidenced findings with CT and MRI 总被引:3,自引:0,他引:3
Haruhiko Ishida Mitsuhiro Mohri Mutsuo Amatsu 《European archives of oto-rhino-laryngology》2002,259(10):535-539
The depth and extent of the invasion of the skull base by a tumor are the most critical information for successful en bloc resection of the tumor. The only means available for the evaluation of these factors are CT or MRI images. In order to clarify the ability of these imaging modes to delineate the invasion of the skull base, preoperative images of ten patients who underwent en bloc resection of skull base tumors at Kobe University Hospital were compared with the histopathological findings of the resected specimens. CT proved to be superior to MRI for evaluating bone destruction of the skull base. On the other hand, MRI provided more useful information about intracranial invasion than CT. As a hypertrophic linear shadow on Gd-enhanced MRI represented dural invasion or thickened dura mater adjacent to the tumor, this technique should be taken into consideration to determine the dural resection. We concluded that preoperative evaluation of the depth of skull base invasion by both CT and Gd-enhanced MRI is essential for planning complete tumor resection. 相似文献