全文获取类型
收费全文 | 5204篇 |
免费 | 229篇 |
国内免费 | 25篇 |
专业分类
耳鼻咽喉 | 14篇 |
儿科学 | 136篇 |
妇产科学 | 48篇 |
基础医学 | 714篇 |
口腔科学 | 174篇 |
临床医学 | 281篇 |
内科学 | 1052篇 |
皮肤病学 | 59篇 |
神经病学 | 610篇 |
特种医学 | 275篇 |
外科学 | 1107篇 |
综合类 | 19篇 |
预防医学 | 189篇 |
眼科学 | 66篇 |
药学 | 284篇 |
中国医学 | 14篇 |
肿瘤学 | 416篇 |
出版年
2022年 | 40篇 |
2021年 | 103篇 |
2020年 | 51篇 |
2019年 | 78篇 |
2018年 | 101篇 |
2017年 | 69篇 |
2016年 | 76篇 |
2015年 | 107篇 |
2014年 | 136篇 |
2013年 | 154篇 |
2012年 | 215篇 |
2011年 | 223篇 |
2010年 | 130篇 |
2009年 | 106篇 |
2008年 | 187篇 |
2007年 | 214篇 |
2006年 | 224篇 |
2005年 | 212篇 |
2004年 | 250篇 |
2003年 | 217篇 |
2002年 | 237篇 |
2001年 | 227篇 |
2000年 | 227篇 |
1999年 | 189篇 |
1998年 | 82篇 |
1997年 | 53篇 |
1996年 | 73篇 |
1995年 | 54篇 |
1994年 | 54篇 |
1993年 | 32篇 |
1992年 | 140篇 |
1991年 | 115篇 |
1990年 | 121篇 |
1989年 | 112篇 |
1988年 | 91篇 |
1987年 | 68篇 |
1986年 | 65篇 |
1985年 | 74篇 |
1984年 | 54篇 |
1983年 | 50篇 |
1979年 | 48篇 |
1977年 | 32篇 |
1975年 | 22篇 |
1974年 | 39篇 |
1973年 | 31篇 |
1972年 | 24篇 |
1971年 | 24篇 |
1970年 | 21篇 |
1968年 | 24篇 |
1967年 | 22篇 |
排序方式: 共有5458条查询结果,搜索用时 171 毫秒
71.
72.
M. Shinohara H. Kuroda Y. Fukaya E. Sato H. Makino 《Journal of artificial organs》2002,5(4):0270-0275
An animal experiment was done using six mongrel dogs that weighed 28 ± 3 kg to show that an accelerometer could detect skeletal
muscle fatigue in dynamic cardiomyoplasty. Through left-side thoracotomy, the heart was exposed and an electrode to sense
the heartbeat was positioned on the left ventricle. A left latissimus dorsi muscle flap (LDMF) was inserted into the left
chest cavity and rolled around the heart. An accelerometer was put on the rolled LDMF to sense the ventricular acceleration
by contraction of the LDMF and the heart. The LDMF was stimulated under these settings: pulse width, 210 μs; stimulation output,
6 V; burst frequency, 30 Hz; burst duration, 200 ms; synchronous ratio, 1 : 4; and synchronous delay, 66 ms. Output voltage
from the accelerometer was recorded 1, 3, 5, 10, and 15 min after the beginning of stimulation. Percentages of the amplitude
in all dogs after 3, 5, 10, and 15 min were 81 ± 10%, 63 ± 12%, 48 ± 11%, and 45 ± 14% of the values after 1 min, respectively.
Significant differences were found between the values after 1 min and those after 3 min, between the values after 3 min and
those after 5 min, and between the values after 5 min and those after 10 min. This study suggests that muscle fatigue is detectable
with an accelerometer in actual dynamic cardiomyoplasty.
Received: May 11, 2001 / Accepted: September 10, 2002
Acknowledgments This work was financially supported in a part by a Grant in Aid for Scientific Research (05671113) from the Ministry of Education,
Science, and Culture of Japan.
Correspondence to:H. Kuroda 相似文献
73.
A new role of uric acid as an antioxidant in human plasma 总被引:1,自引:0,他引:1
Free radical attack upon uric acid (UA) nonenzymatically generates allantoin (ALT), and the presence of ALT in human plasma suggests free radical intervention within the body. To assess this possibility, we determined plasma ALT in patients with chronic renal failure (CRF) and some other diseases by high-performance liquid-chromatography (HPLC). Heparinized blood samples were obtained from 15 healthy controls, CRF patients under conservative management (n = 13) or hemodialysis (HD) treatment (n = 8) and patients with gout (n = 11) or rheumatoid arthritis (RA, n = 13). Although not seen in normal plasma samples, ALT was detected in 63% and 31% of patients receiving HD and conservative treatment, respectively. The plasma ALT level decreased after each HD session. ALT was also detected in 18% and 23% of the patients with gout and RA, respectively. ALT was found to be generated by ultraviolet radiation or by the addition of H2O2 to a normal pool-plasma. Addition of Fe(2+) and H2O2 increased the ALT level to about twice that of only H2O2. Addition of either catalase, desferal, EDTA, DMTU, DMSO or mannitol to the plasma decreased ALT generation. These findings suggest that ALT is generated from UA attacked by free radicals, especially by the hydroxyl radical, and that UA plays a role as an antioxidant in the plasma of patients with CRF and some other diseases. 相似文献
74.
Body-oriented therapies as relaxation training and certain forms of meditation are gaining popularity in the treatment and prevention of psychosomatic disorders. In this paper, a new method of self-control called self-regulation method (SRM), derived from autogenic training and Zen meditation, is presented. The technique of SRM is introduced. Secondly, physiological studies on SRM using skin temperature, galvanic skin response, and cortical evoked potentials are presented. Thirdly, the results of psychological tests conducted on SRM are presented. These psycho-physiological studies suggest that SRM may elicit a state of 'relaxed alertness'. Fourthly, clinical applications of SRM are discussed, and 3 cases are presented. Finally, SRM is discussed in relation to the psychology and physiology of 'relaxed alertness'. 相似文献
75.
Summary Resting cartilages taken from 2-day-old mouse ribs were transplanted into spleens in order to carry out morphological investigations of the life cycles of their chondrocytes. The explants were isografted for periods of up to 60 days and examined at light and electron microscopic levels, using von Kossa's reaction or osmium-potassium ferrocyanide (OPF) fixation. By day 3 after transplantation, resting cartilage containing immature chondrocytes was well adapted to splenic tissue and by 7 days after transplantation these chondrocytes had changed into early hypertrophic chondrocytes containing large vacuoles, glycogen aggregates and abundant secretory organelles. It was also demonstrated by von Kossa's reaction that the initial calcification occurred in the territorial matrix during this period. In spite of the hypertrophic chondrocytes in the central zone being surrounded by an extensively calcified matrix during days 14–21 after transplantation, these cells had well-preserved organized organelles, except that Golgi-associated elements and endoplasmic reticulum revealed a tendency toward degenerative changes. With increased duration of the grafting period, from 30–60 days, the calcification zone progressed gradually, and the number of hypertrophic chondrocytes embedded in the calcified matrix decreased considerably. By day 60, degenerating hypertrophic chondrocytes of two types were distinguished: flattened cells containing large vacuoles, poorly developed Golgi apparatuses, and rough endoplasmic reticulum; and shrunken dark cells displaying terminal hypertrophy. During the present study, we observed no vascular invasion into the calcified matrix, or appearance of bone-related cells, and the morphological changes from the resting chondrocytes to cellular hypertrophy accompanied by the formation of a calcified matrix were observed at day 60. These findings indicate that resting cartilage cells of the mouse have the capacity for terminal differentiation when transplanted into the spleen. 相似文献
76.
Honda T Nishizawa T Uenobe M Kohchi C Kuroda A Ototake M Nakanishi T Yokomizo Y Takahashi Y Inagawa H Soma G 《Molecular immunology》2005,42(1):1-8
The M-CSF and its receptor (M-CSFR, CSF-1R or c-fms proto-oncogene) system were initially implicated as essential in mammals for normal monocyte development as well as for pregnancy. To allow a comparison with the M-CSF and M-CSFR system of an oviparous animal, we cloned a M-CSFR-like gene from rainbow trout (Oncorhynchus mykiss). The gene was cloned from a cDNA library of head kidney. It contained an open reading frame encoding 967 amino acids with a predicted size of 109 kDa. The putative amino acid sequence of rainbow trout M-CSFR showed 54% amino acid identity to fugu (Takifugu rubripes) M-CSFR, 52% to zebrafish (Danio rerio) M-CSFR and 40% to mouse (Mus musculus) and human (Homo sapiens) M-CSFR. The M-CSFR-like gene was constitutively expressed in head kidney, kidney, intestine, spleen and blood. The gene was detected especially in the ovary of immature female rainbow trout. These results suggest that a M-CSFR-like receptor may be involved in female reproductive tracts even in an oviparous animal like fish. 相似文献
77.
Fujii S Kuroda Y Ito KL Yoshioka M Kaneko K Yamazaki Y Sasaki H Kato H 《Neuroscience letters》2000,279(2):121-124
A train of low-frequency afferent stimuli (LFS, 1 Hz, 1000 pulses), given 60 min prior to a tetanus (100 Hz, 100 pulses), suppresses the induction of long-term potentiation (LTP) in which a short-term potentiation decreases gradually back to the pre-tetanic level within 40-50 min (LTP suppression). We investigated the effects of adenosine A1 or A2 receptor antagonists (8-cyclopentyltheophylline (8-CPT) and CP-66713, respectively) on LTP suppression in CA1 neurons of guinea pig hippocampal slices. When the LFS was delivered in the presence of 8-CPT (1 microM), LTP suppression was not significantly affected. However, when LFS was delivered in the presence of CP-66713 (10 microM), LTP suppression was inhibited, leading to successful LTP induction. These results indicate that endogenous adenosine, acting via A2 receptors, is involved in the mechanism of LTP suppression. 相似文献
78.
Tetsuya Murata Shigeo Nakamura Hiroya Kato Yasushi Yatabe Taizo Shiraishi Makoto Kuroda Ryulchi Yatani Taizan Suchi 《Pathology international》1997,47(11):801-805
A case of Hodgkln's disease (HD), lymphocyte depression (LD) type In an Immunosuppressive patient is described. The patient was a 48-year-old male and his parents were born In the Kyushu area, which is an endemic area for adult T cell lymphomaheukemla (ATL). He was seropositive for ATL virus (ATLV, also referred to as HTLV-I) and showed a marked Immunosuppressive condition. He developed LD-HD and Pneumocystis carinii pneumonia, and died due to respiratory failure. The Immunohistochemical and in situ hybridization analyses revealed that the Reed-Sternberglike cells In the lymph node biopsy sample were positive for Ber-H2 (CD30), Leu-M1 (CD15), L-26 (CD20), Bcl-2, p53 and EBER, the viral genome of Epstein-Barr virus (EBV). 相似文献
79.
IgE antibody production is associated with suppressed interferon-gamma levels in mesenteric lymph nodes of rats infected with the nematode Nippostrongylus brasiliensis. 总被引:1,自引:0,他引:1
下载免费PDF全文
![点击此处可从《Immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
IgE and IgG2a antibody production and interferon (IFN)-gamma secretion were studied in rats infected with the gut nematode Nippostrongylus brasiliensis by in vitro cultivation of mononuclear cells obtained from spleen (SPL), mesenteric lymph nodes (MLN) and pulmonary hilar lymph nodes (PLN). The highest levels of IgE were detected in the culture supernatants of MLN cells after infection: IgE levels were modest in PLN and negligible in SPL. In contrast, the highest levels of IgG2a were produced by PLN cells, followed by MLN and SPL cells. These results indicate that the MLN is the most significant site for IgE production in nematode infection, while IgG2a production is more marked in PLN. In naive rats, the spontaneous secretion of IFN-gamma was highest in PLN cells, followed by MLN and SPL cells. After the infection, IFN-gamma levels were significantly decreased in MLN and PLN. Suppression of IFN-gamma secretion was also observed in concanavalin A (ConA)-stimulated MLN and PLN cells from infected rats. In MLN, the ratio of CD4+ to CD8+ T cells was increased after the infection. Stimulation with an allergen-rich, excretory-secretory (ES) substance of the nematode enhanced ongoing IgE production, and suppressed IFN-gamma secretion by MLN and PLN cells. In contrast, an allergen-poor, adult worm extract potentiated IFN-gamma secretion. These results show that nematode-induced IgE antibody response is associated with the suppressed production and/or secretion of IFN-gamma, particularly in the MLN, and that some molecules in the ES substance may trigger these immune responses. 相似文献
80.
Masahiro Kamouchi Takanari KitazonoTetsuro Ago Masanori WakisakaJunya Kuroda Kuniyuki NakamuraNoriko Hagiwara Hiroaki OoboshiSetsuro Ibayashi Mitsuo Iida 《Neuroscience letters》2007
Objective: The aims of the present study were to elucidate the interaction of reactive oxygen species (ROS) and Ca2+ response in central nervous system (CNS) pericytes. Methods: The intracellular Ca2+ concentration was measured using fluorescent Ca2+ indicator, fura-2, in cultured CNS pericytes. Results: Hydrogen peroxide evoked a dose-dependent increase in cytosolic Ca2+, which was completely inhibited by catalase. Removal of external Ca2+ or addition of nicardipine (1 μM) during application of hydrogen peroxide did not affect Ca2+ response. Incubation of the cells in Ca2+ free solution did not abolish but slightly reduced Ca2+ response by hydrogen peroxide. Ca2+ response to hydrogen peroxide was not altered by the depletion of intracellular Ca2+ by thapsigargin (1 μM). Pretreatment of the cells with tyrosine kinase inhibitor genistein (100 μM) or tyrphostin A47 (30 μM) significantly reduced Ca2+ increase by hydrogen peroxide. Conclusions: These results indicate that hydrogen peroxide evokes Ca2+ increase predominantly by release from intracellular Ca2+ store, which may be regulated by tyrosine kinases. 相似文献