全文获取类型
收费全文 | 7896篇 |
免费 | 314篇 |
国内免费 | 55篇 |
专业分类
耳鼻咽喉 | 42篇 |
儿科学 | 130篇 |
妇产科学 | 78篇 |
基础医学 | 937篇 |
口腔科学 | 228篇 |
临床医学 | 525篇 |
内科学 | 1927篇 |
皮肤病学 | 233篇 |
神经病学 | 551篇 |
特种医学 | 303篇 |
外科学 | 1437篇 |
综合类 | 29篇 |
一般理论 | 1篇 |
预防医学 | 221篇 |
眼科学 | 241篇 |
药学 | 642篇 |
中国医学 | 7篇 |
肿瘤学 | 733篇 |
出版年
2023年 | 41篇 |
2022年 | 104篇 |
2021年 | 156篇 |
2020年 | 80篇 |
2019年 | 83篇 |
2018年 | 143篇 |
2017年 | 119篇 |
2016年 | 132篇 |
2015年 | 152篇 |
2014年 | 169篇 |
2013年 | 238篇 |
2012年 | 387篇 |
2011年 | 473篇 |
2010年 | 240篇 |
2009年 | 206篇 |
2008年 | 339篇 |
2007年 | 402篇 |
2006年 | 381篇 |
2005年 | 402篇 |
2004年 | 413篇 |
2003年 | 432篇 |
2002年 | 422篇 |
2001年 | 184篇 |
2000年 | 205篇 |
1999年 | 180篇 |
1998年 | 128篇 |
1997年 | 84篇 |
1996年 | 73篇 |
1995年 | 66篇 |
1994年 | 65篇 |
1993年 | 63篇 |
1992年 | 157篇 |
1991年 | 142篇 |
1990年 | 131篇 |
1989年 | 145篇 |
1988年 | 122篇 |
1987年 | 124篇 |
1986年 | 108篇 |
1985年 | 148篇 |
1984年 | 68篇 |
1983年 | 50篇 |
1979年 | 43篇 |
1978年 | 34篇 |
1977年 | 30篇 |
1976年 | 31篇 |
1975年 | 31篇 |
1974年 | 39篇 |
1973年 | 35篇 |
1972年 | 48篇 |
1969年 | 36篇 |
排序方式: 共有8265条查询结果,搜索用时 15 毫秒
101.
Taki Y Goto R Evans A Zijdenbos A Neelin P Lerch J Sato K Ono S Kinomura S Nakagawa M Sugiura M Watanabe J Kawashima R Fukuda H 《Neurobiology of aging》2004,25(4):455-463
The objectives of this study were to evaluate the correlations of the volumes of the gray matter and white matter with age, and the correlations of the tissue probabilities of the gray matter and white matter with age and several cerebrovascular risk factors. We obtained magnetic resonance (MR) images of the brain and clinical information from 769 normal Japanese subjects. We processed the MR images automatically by correcting for inter-individual differences in brain size and shape, and by segmenting the MR images into the gray matter and white matter. Volumetry of the brain revealed a significant negative correlation between the gray matter volume and age, which was not observed between white matter volume and age. Voxel-based morphometry showed that age, systolic blood pressure, and alcohol drinking correlated with the regional tissue probabilities of the gray matter and white matter. 相似文献
102.
Nagahira K Fukuda Y Oyama Y Kurihara T Nasu T Kawashima H Noguchi C Oikawa S Nakanishi T 《Journal of immunological methods》1999,222(1-2):83-92
An anti-human tumor necrosis factor-alpha (TNF-alpha) monoclonal antibody, designated as 3B10, inhibits the biological activity of human TNF-alpha. In the present study, we constructed humanized version of the antibody by grafting its complementarity-determining regions (CDRs) onto a human antibody, HBS-1. Using a molecular model of mouse 3B10, framework residues affecting the CDR conformation were identified. Thus, these residues were also introduced into the framework together with the CDRs in a stepwise manner, depending on the degree of the possible importance of the residues. As a result, one humanized version (h3B10-9) which possesses nine mouse framework residues showed the same binding activity as that of the chimeric version. This humanized anti-TNF-alpha antibody is expected to be less immunogenic and thus more suitable for possible clinical use. 相似文献
103.
Yamada M Narita M Nakamura K Tsuboi T Kawashima K 《Journal of comparative pathology》2003,128(2-3):140-145
Three calves aged 1 week (group 1), three aged 6 weeks (group 2) and three aged 6 weeks (having been pretreated with dexamethasone) (group 3) were infected endobronchially with bovine adenovirus type 3 (BAV-3). All calves had received colostrum. The histopathological, immunohistochemical, ultrastructural and TUNEL features were examined on post-inoculation day (PID) 3, 5 and 7. Viral replication and intranuclear inclusions were frequently observed in groups 1 and 3, but not in group 2. The lesions became progressively severe on PID 5 and 7 in group 1. In group 3, however, the cellular injury caused by BAV-3 was of short duration and the lesions began to resolve at PID 7. Numerous apoptotic cells were seen in the PID 3 calves of all three groups, and in the PID 7 calves of groups 2 and 3; however, the PID 5 and 7 calves of group 1 showed only a few apoptotic cells in the alveolar septa. The results indicated that (1) the durability of BAV-3 infection in the lung was closely related to apoptosis, and (2) the host defence mechanism that induced apoptosis in infected cells was age-related. 相似文献
104.
11q trisomy detected by fluorescence in situ hybridization 总被引:1,自引:0,他引:1
Takako Takano Yasuko Yamanouchi Shoko Kawashima Masatsune Date Shintaro Hashira Mitsushiro Kida Toshiaki Abe Yutaka Nakahori Yasuo Nakagome 《Clinical genetics》1993,44(6):324-328
Takano T, Yamanouchi Y, Kawashima S, Date M, Hashira S, Kida M, Abe T, Nakahori Y, Nakagome Y. 11q trisomy detected by fluorescence in situ hybridization. Clin Genet 1993: 44: 324–328. © Munksgaard, 1993 A patient with psychomotor developmental delay, multiple minor anomalies, congenital heart disease and left inguinal hernia is reported. His karyotype was 45,X/46,X,+mar (3 : 37 cells), and the marker chromosome was identified as t(Y;11) (q12;q14?) using fluorescence in situ hybridization and fluorescent chromosome painting. He was diagnosed as mosaic for de novo 11q trisomy. 相似文献
105.
We examined the distribution of enterofugal nerve terminals of bombesin-, cholecystokinin- and vasoactive intestinal polypeptide-like immunoreactivity in the rat celiac-superior mesenteric ganglion complex. The majority of these nerve terminals were concentrated in the mesenteric side of the ganglion. The present findings suggest that some functional specialization occurs in the celiac ganglion of the rat. 相似文献
106.
Takahiro Hasebe Kiyoshi Mukai Kazuyuki Ishihara Akihiro Kaneko Yukio Shimosato 《Pathology international》1992,42(8):585-594
Thirteen sebaceous gland carcinomas and 10 sweat gland carcinomas were examined to elucidate any important histological parameters influencing their prognosis, and the relationship between immunohistochemical expressions of c-erbB-2 oncoprotein and survival of the patients was analyzed. Sebaceous gland carcinomas with vacuolated cytoplasm in more than 50% of whole tumor area, with necrosis, and without lymphoid cell infiltration in tumor nests and stroma had a higher incidence of tumor recurrence and tumor-related death than tumors with vacuolated cytoplasm in 50% or less of whole tumor area (p < 0.01), without necrosis, and with lymphoid cell infiltration in tumor nest and stroma (p < 0.05). Sweat gland carcinomas of all cases with fatal outcomes demonstrated tubular differentiation in 20% or less of whole tumor area, lymphatic permeation and desmoplastic reaction. Three sebaceous gland carcinomas and three sweat gland carcinomas were positive for c-erbB-2 oncoprotein. Two of three sebaceous gland carcinomas, and all three sweat gland carcinomas developed tumor recurrence and ended in tumor-related deaths. Sweat gland carcinomas with c erbB 2 expression had significantly shorter survival than those with negative immunostain (p < 0.01). Cytoplasmic appearance, tumor necrosis, and lymphoid cell infiltration in tumor nests and stroma of sebaceous gland carcinoma, and tubular differentiation, lymphatic permeation, and growth patterns of sweat gland carcinoma are considered to closely correlate to the prognosis. Immunohisto-chemically detected c erbB 2 oncoprotein may be an indicator of bad prognosis. Acta Pathol Jpn 42: 585–594, 1992. 相似文献
107.
Presynaptic M1 muscarinic receptor modulates spontaneous release of acetylcholine from rat basal forebrain slices 总被引:2,自引:0,他引:2
Spontaneous release of acetylcholine (ACh) from rat basal forebrain slices in the presence of cholinesterase inhibitor was directly determined using a specific radioimmunoassay for ACh. The release was calcium dependent. A consistent amount of ACh release was observed throughout the experiment. Atropine (10(-8) to 10(-5) M) and pirenzepine (10(-7) to 10(-5) M) enhanced spontaneous ACh release. These findings indicate the presence of an M1 muscarinic autoreceptor that modulates spontaneous release of ACh in the rat basal forebrain. 相似文献
108.
The anatomical relationship between the kidney position and its arterial supply was investigated in 21 mammals, 1 bird, and 3 reptiles (n = 1 for each species) and in 43 human cadavers. The following observations were made. (1) Although the right kidney was located caudal to the left kidney in 29 out of 43 human cadavers (67.4%), the origin of the right renal artery from the aorta was located cranial to the origin of the left renal artery in 36 human cadavers (83.7%). Therefore, the relative positions of the kidneys do not correspond with the relative origins of the renal arteries in humans. (2) Among the mammals that were examined, the position of the kidney and the branching level of the renal artery on the right side were usually cranial to those on the left side. (3) In the bird and most reptiles that were examined, kidneys were typically located in the pelvic region and were supplied by segmental arterial branches. These results suggest that the right kidney and its arterial supply are generally located cranial to the left kidney in phylogeny of mammals. While the presence of a human accessory renal artery in 9 out of 86 sides (10.5%) and a cranial origin of the left renal artery relative to the right renal artery in 7 out of 43 cadavers (16.3%), shows some variation in the arterial supply to the kidneys, the origin of the renal arteries can generally be used as phylogenetic landmarks indicating the relative positions of the kidneys. Hence, from an ontological perspective, the human right kidney may be initially situated cranial to the left kidney during the early stages of development. Thereafter, the human right kidney may shift downwards secondary. 相似文献
109.
In the anesthetic management of five patients undergoing excision of pheochromocytoma, adenosine triphosphate (ATP) was used for the purpose of regulating systemic arterial pressure during the period of tumor manipulation. ATP was administered at doses of 0.05–0.4mg/kg/min. Systemic arterial pressure showed a significant decrease from 162 ± 17/103 ± 11mmHg before manipulation to 136 ± 21/81 ± 10mmHg during the manipulation period. The plasma catecholamine levels showed significant increases in this period. Immediately after excision, the systemic arterial pressure was maintained at normal levels (118 ± 13/75 ± 16mmHg) by fluid replacement and discontinuation of ATP administration, subsequently becoming 129 ± 19/79 ± 16mmHg. The heart rate was very stable and tachycardia did not ocurr during the manipulation period. Only one arrhythmic episode ocurred in one patient. The systemic vascular resistance index was significantly lower during the manipulation period than before it. It was therefore considered that ATP was useful as an agent for controlling arterial pressue during the anesthesia for pheochromocytoma.(Murata K, Sodeyama O, Ikeda K et al.: Prevention of hypertensive crisis with ATP during anesthesia for pheochromocytoma. J Anesth 1: 162–167, 1987) 相似文献
110.
Postanesthetic respiratory depression in humans: A comparison of sevoflurane,isoflurane and halothane 总被引:1,自引:0,他引:1
The postanesthetic respiratory depression with sevoflurane, isoflurane and halothane was studied in twenty-one patients. They were divided into three groups of seven patients each. One group underwent sevoflurane anesthesia, another group isoflurane and the third group halothane. Following extubation, the decrease in blood concentration of the anesthetic agent was most rapid with sevoflurane and slowest with halothane. Twenty minutes following extubation, resting ventilation and ventilatory response to carbon dioxide returned to the preanesthetic state with sevoflurane and isoflurane anesthesia. With halothane anesthesia, however, the depressive respiratory effects of halothane remained; depressed ventilatory response to carbon dioxide, decreased tidal volume and increased respiratory frequency. Although halothane has been reported to have the least depressive respiratory effect of the three, its elimination was slowest. Thus the respiratory effects of halothane persisted up to and past the twenty minute mark, far longer than with sevoflurane or isoflurane.(Doi M, Ideda K: Postanesthetic respiratory depression in humans: A comparison of sevoflurane, isoflurane and halothane. J Anesth 1: 137–142, 1987) 相似文献