全文获取类型
收费全文 | 4216篇 |
免费 | 276篇 |
国内免费 | 13篇 |
专业分类
耳鼻咽喉 | 20篇 |
儿科学 | 82篇 |
妇产科学 | 36篇 |
基础医学 | 590篇 |
口腔科学 | 127篇 |
临床医学 | 318篇 |
内科学 | 1047篇 |
皮肤病学 | 61篇 |
神经病学 | 309篇 |
特种医学 | 162篇 |
外科学 | 727篇 |
综合类 | 30篇 |
预防医学 | 194篇 |
眼科学 | 111篇 |
药学 | 313篇 |
中国医学 | 7篇 |
肿瘤学 | 371篇 |
出版年
2023年 | 25篇 |
2022年 | 36篇 |
2021年 | 51篇 |
2020年 | 39篇 |
2019年 | 40篇 |
2018年 | 63篇 |
2017年 | 57篇 |
2016年 | 58篇 |
2015年 | 80篇 |
2014年 | 84篇 |
2013年 | 79篇 |
2012年 | 140篇 |
2011年 | 145篇 |
2010年 | 102篇 |
2009年 | 104篇 |
2008年 | 157篇 |
2007年 | 156篇 |
2006年 | 167篇 |
2005年 | 185篇 |
2004年 | 172篇 |
2003年 | 169篇 |
2002年 | 160篇 |
2001年 | 171篇 |
2000年 | 162篇 |
1999年 | 163篇 |
1998年 | 59篇 |
1997年 | 52篇 |
1996年 | 53篇 |
1995年 | 37篇 |
1994年 | 49篇 |
1993年 | 39篇 |
1992年 | 121篇 |
1991年 | 110篇 |
1990年 | 132篇 |
1989年 | 120篇 |
1988年 | 94篇 |
1987年 | 105篇 |
1986年 | 76篇 |
1985年 | 79篇 |
1984年 | 60篇 |
1983年 | 50篇 |
1982年 | 33篇 |
1979年 | 50篇 |
1978年 | 37篇 |
1977年 | 30篇 |
1974年 | 38篇 |
1973年 | 37篇 |
1972年 | 39篇 |
1971年 | 34篇 |
1969年 | 25篇 |
排序方式: 共有4505条查询结果,搜索用时 15 毫秒
1.
N Ogata 《Brain research》1987,403(2):225-233
The action of gamma-aminobutyric acid (GABA) in the supraoptic nucleus was investigated using guinea pig brain slices. GABA produced a membrane depolarization accompanied by a decrease in the input resistance. The action of GABA was concentration-dependent throughout a wide range of concentrations (10(-7)-10(-3) M). In none of the cells examined, a membrane hyperpolarization was observed. The reversal potential for the depolarization induced by GABA was about 25 mV positive to the resting membrane potential. The amplitude of the GABA-induced depolarization was increased to 1.5 X the control by reducing the external Cl- from 134.2 mM to 10.2 mM. The action of GABA was readily antagonized by relatively low concentrations of bicuculline (10(-5) M). The action of GABA in the hippocampus or in the anterior hypothalamus was markedly different from that in the supraoptic nucleus, i.e. GABA produced both depolarizing and hyperpolarizing responses in the hippocampus and consistently a hyperpolarization in the anterior hypothalamus. The depolarizing but not the hyperpolarizing response in the hippocampus was selectively blocked by picrotoxin (2 X 10(-5) M) or by bicuculline (10(-5) M). The depolarizing component was dependent on the external Cl- concentration and had a reversal potential similar to that of the depolarization induced by GABA in the supraoptic nucleus. The hyperpolarizing component was resistant to bicuculline and had a reversal potential about 30 mV negative to the resting membrane potential.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
2.
Y Moizumi Y Abe M Hata Y Tsuru I Suzuki Y Ogata 《Kyobu geka. The Japanese journal of thoracic surgery》1990,43(13):1052-1055
The centrifugal pump (bio-pump) as a temporary shunt during the operation of the descending thoracic aortic aneurysms was used as effective means of providing adequate circulation to the lower body. But in the acute excessive bleeding, estimates of the flow to the abdominal viscera as well as spinal cord are variable. We employed bio-pump with an interposed soft reservoir under low dose systemic heparinization in 2 cases of the descending thoracic aortic aneurysms. Both cases had been maintained adequate flow and perfusion pressure in the time of acute excessive hemorrhage, and there were no evidence of the organ failures due to microembolism. Furthermore, postoperative hemorrhage by using low dose heparin seemed to be unrisky. Compared with the previous method, bio-pump with an interposed soft reservoir provides adequate circulation to the lower body even if acute excessive bleeding occurred. 相似文献
3.
Roberto Civitelli M.D. Eturo Ogata Louis V. Avioli Gary Stein Samuel Edelstein John A. Eisman Yasuho Nishii Hajime Orimo Jane Lian Takuo Fujita Yasufumi Hayashi Shigeaki Kato Tadashi Kobayashi Hirotoshi Morii Rikushi Morita Toshitaka Nakamura Yoshiki Seino Masataka Shiraki Tatsuo Suda Naoyuki Takahashi Hideaki Takahashi Tastuhiko Tanisawa Akifumi Tokita 《Calcified tissue international》1995,57(6):409-414
4.
Tsutomu Ogata Peter Goodfellow Christine Petit Pierre Maroteaux Nobutake Matsuo 《American journal of medical genetics. Part A》1993,45(1):101-104
This is a follow-up report on a male patient with a 46, Y, r(X) karyotype. Although he had no clinico-radiological features of X-linked recessive chondrodysplasia punctata (CDPX1), molecular studies revealed an Xp terminal deletion involving the putative region for the CDPX1 locus (PABX-DXS31). We suspect that the absence of CDPX1 may be attributable to the nature of the disease and the extreme short stature of the patient (mean – 5.6 S.D.). © 1993 Wiley-Liss, Inc. 相似文献
5.
Deficiency of insulin receptor substrate-1 impairs skeletal growth through early closure of epiphyseal cartilage. 总被引:5,自引:0,他引:5
Kazuto Hoshi Naoshi Ogata Takashi Shimoaka Yasuo Terauchi Takashi Kadowaki Shin-Ichi Kenmotsu Ung-Il Chung Hedehiro Ozawa Kozo Nakamura Hiroshi Kawaguchi 《Journal of bone and mineral research》2004,19(2):214-223
Morphological analyses in and around the epiphyseal cartilage of mice deficient in insulin receptor substrate-1 (IRS-1) showed IRS-1 signaling to be important for skeletal growth by preventing early closure of the epiphyseal cartilage and maintaining the subsequent bone turnover at the primary spongiosa. Introduction: IRS-1 is an essential molecule for intracellular signaling by IGF-I and insulin, both of which are potent anabolic regulators of cartilage and bone metabolism. To clarify the role of IRS-1 signaling in the skeletal growth, morphological analyses were performed in and around the epiphyseal cartilage of mice deficient in IRS-1 (IRS-1(-/-)), whose limbs and trunk were 20-30% shorter than wildtype (WT) mice. MATERIALS AND METHODS: The epiphyseal cartilage and the primary spongiosa at proximal tibias of homozygous IRS-1(-/-) and WT male littermates were compared using histological, immunohistochemical, enzyme cytohistochemical, ultrastructural, and bone histomorphometrical analyses. RESULTS: In and around the WT epiphyseal cartilage, IRS-1 and insulin-like growth factor (IGF)-1 receptors were widely expressed, whereas IRS-2 was weakly localized in bone cells. Chronological observation revealed that height of the proliferative zone and the size of hypertrophic chondrocytes were decreased in WT mice as a function of age, and these decreases were accelerated in the IRS-1 (-/-) cartilage, whose findings at 12 weeks were similar to those of WT at 24 weeks. In the IRS-1(-/-) cartilage, proliferating chondrocytes with positive proliferating cell nuclear antigen (PCNA) or parathyroid hormone (PTH)/PTH-related peptide (PTHrP) receptor immunostaining had almost disappeared by 12 weeks. Contrarily, TUNEL+ apoptotic cells were increased in the hypertrophic zone, at the bottom of which most of the chondrocytes were surrounded by the calcified matrix, suggesting the closure of the cartilage. In the primary spongiosa, bone volume, alkaline phosphatase (ALP)+ osteoblasts, TRACP+ osteoclasts, and the osteopontin-positive cement line were markedly decreased. Bone histomorphometrical parameters for both bone formation and resorption were significantly lower in IRS-1(-/-) mice, indicating the suppression of bone turnover. CONCLUSION: The IRS-1(-/-) epiphyseal cartilage exhibited insufficient proliferation of chondrocytes, calcification of hypertrophic chondrocytes, acceleration of apoptosis, and early closure of the growth plate. Thus, the data strongly suggest that IRS-1 signaling is important for the skeletal growth by preventing early closure of the epiphyseal cartilage and by maintaining the subsequent bone turnover at the primary spongiosa. 相似文献
6.
Yoshiko Ogata Yoshihiro Mori Hikari Koga Kazuya Awai Yukako Arakawa Norihiko Nakanishi Mikio Kataoka Fumikazu Kohi 《Nihon Kokyūki Gakkai zasshi》2004,42(9):837-841
A 22-year-old man was urgently admitted for pneumothorax. He continued complaining of exertional dyspnea and dry cough after the pneumothorax healed. About three months later, an atypical pulmonary mycobacteriosis by mycobacterium kansasii was identified. Exertional dyspnea increased after chemotherapy was administered, and the patient was readmitted because of difficulty in daily life activities. Chest radiographs and CT scans showed bilateral pulmonary hyperinflation and a narrowed heart shadow. There was also marked combined ventilatory impairment, as identified by a respiratory function test. Furthermore, the histological findings of surgically removed lung tissue revealed accumulation of lymphocytes in the wall of a small bronchus. Idiopathic bronchiolitis obliterans was diagnosed from the clinical course and clinical findings. The patient is now being monitored and is awaiting lung transplantation. 相似文献
7.
8.
Summary. We describe a method of quantifying the lateral/medial thrust of the knee which occurs in the early phase of walking. We
have used this method to evaluate the effects of wedged insoles on the lateral and medial thrust for normal knees and knees
with unicompartment osteoarthritis (OA). A laterally elevated (valgus) insole decreased the lateral thrust of both normal
and osteoarthritic knees. A medially elevated (varus) insole increased the lateral thrust. In 50 symptomatic knees with medial
compartment OA, decreasing the lateral thrust with a valgus insole reduced pain on walking in 27. Patients whose pain was
reduced by valgus insoles tended to have earlier OA and to have a significantly greater reduction in the lateral thrust than
in the 23 remaining unaffected knees. A varus insole was effective in decreasing the medial thrust and reducing pain in all
ten knees with lateral compartment OA. We recommend the use of valgus insoles for patients with painful early medial compartment
OA and the use of varus insoles for lateral compartment OA.
Accepted: 28 February 1996 相似文献
Résumé. Les auteurs présentent une méthode d’évaluation quantitative, avec mesure par un accéléromètre, des écarts internes ou externes qui se font au niveau du genou dans la première phase du pas. Ils ont étudié les effets dynamiques et l’utilité clinique des semelles à coin valgisant ou varisant pour les genous atteints d’arthrose unicompartimentale. Une semelle à coin externe (valgisante) diminue l’écart externe ou augmente l’écart interne que subit le genou normal ou arthrosique. L’effet est inverse pour une semelle à coin interne. Sur 50 genoux atteints d’arthrose interne avec écart externe, la semelle à coin valgisant diminue les douleurs à la marche dans 27 cas et est inefficace dans 23 cas. Les genoux pour lesquels les semelles valgisantes sont efficaces ont une réduction significative de l’écart externe par rapport à ceux pour lesquels ces semelles sont inefficaces. La semelle valgisante est plus efficace en cas d’arthrose du genou débutante qu’en cas d’arthrose évoluée. La semelle varisante est active pour les 10 genoux avec arthrose compartimentale externe et écart interne.
Accepted: 28 February 1996 相似文献
9.
The sialosyl-Tn (STn) antigen is a mucin-associated carbohydrate antigen expressed by a variety of adenocarcinomas. In the colon, expression of this antigen has been associated with a poor prognosis, independent of tumor stage or histology. The present study was performed to determine whether this adverse clinical outcome might be due to an interaction between STn-positive mucin and natural killer (NK) cell cytotoxicity. Ovine submaxillary mucin (OSM), a mucin highly rich in STn antigen, partially inhibited NK cell cytotoxicity against K562 target cells, but only at high concentrations. Low concentrations of OSM were not inhibitory but became markedly inhibitory in the presence of ammonium ions. Two other STn-positive submaxillary mucins also markedly inhibited NK cytotoxicity when combined with ammonium ions. Removal of sialic acid from OSM reversed the OSM/ammonium-mediated inhibition of NK cell activity. Unlike the submaxillary mucins, two mucins derived from human breast and lung cancer cells which lack the STn antigen, did not inhibit NK cell activity in this system. Likewise, four other non-mucin glycoproteins which lack STn expression did not inhibit NK cells despite having levels of sialic acid that were, in some cases, comparable to submaxillary mucin. These results indicate that mucins bearing the cancer-associated STn antigen can effectively inhibit NK cell cytotoxicity in the presence of ammonium ions. While this NK cell inhibition is likely to be caused by ammonium, mucin markedly enhances this effect, thereby implicating a novel immunomodulatory property of mucin. 相似文献
10.