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991.
Nozawa M Shitoto K Hirose T Matsuda K Michino K Kajihara H Maezawa K Kurosawa H 《Archives of orthopaedic and trauma surgery》2000,120(7-8):376-379
The operative procedures chosen for arthrosis with severe acetabular dysplasia vary among orthopaedic surgeons. We operated
on 250 hips using the rotational acetabular osteotomy (RAO) method of Ninomiya and Tagawa [8]. In this report, we describe
the technique of RAO and the results of this procedure in patients with severely dysplastic hips. Among the 250 hips, there
were 6 which were classified as Severin group V. In those hips, the CE angle was less than 0°, and the femoral head showed
superolateral subluxation. After acetabular osteotomy with straight and curved osteotomes, smooth inferolateral rotation could
be done in all cases. At the latest follow-up symptoms were improved remarkably, especially pain. Radiographically, adequate
coverage of the femoral head was achieved and joint congruence improved in all 6 hips.
Received: 23 June 1999 相似文献
992.
Kazuhiro Nishii Natsuki Matsushita Hirohide Sawada Hiromi Sano Yukihiro Noda Takayoshi Mamiya Toshitaka Nabeshima Ikuko Nagatsu Tadayoshi Hata Kazutoshi Kiuchi Hideo Yoshizato Kunio Nakashima Toshiharu Nagatsu Kazuto Kobayashi 《Journal of neuroscience research》1998,54(4):450-464
Mice lacking expression of tyrosine hydroxylase (TH), the first and rate-limiting enzyme of the catecholamine biosynthetic pathway, in dopaminergic neuronal cell types were generated by a transgenic rescue approach to clarify the role of dopamine signaling during postnatal development. Introduction of the TH transgene directed by the dopamine β-hydroxylase gene promoter into TH knockout mice restored noradrenaline and adrenaline synthesis, preventing perinatal lethality and cardiac dysfunction in the knockout mice. Lack of TH expression in the cells that normally express the dopaminergic phenotype resulted in a marked reduction of dopamine accumulation in the tissues, which led to multiple behavioral abnormalities at the juvenile stage. These abnormalities were characterized by a reduction in spontaneous locomotor activity, blockade of methamphetamine-induced hyperactivity, cataleptic behavior, and defects in active avoidance learning. In contrast, development of the pituitary gland as well as production and secretion of the pituitary peptide hormones dependent on hypothalamic dopaminergic control were normally maintained, despite defective dopamine synthesis. These results demonstrate that dopamine neurotransmission is essential for controlling spontaneous and voluntary movement and associative learning during postnatal development through the nigrostriatal and mesocorticolimbic pathways. J. Neurosci. Res. 54: 450–464, 1998. © 1998 Wiley-Liss, Inc. 相似文献
993.
Kunio Koshimura Yoshio Murakami Junko Tanaka Yuzuru Kato 《Journal of neuroscience research》1998,54(5):664-672
Nitric oxide (NO) has cytotoxic effects but NO producing neurons are resistant to NO toxicity. These results suggest the presence of self-protecting factors for NO toxicity. Recently, 6R-tetrahydrobiopterin (6R-BH4), a cofactor for NO synthase (NOS), has been reported to degrade NO raising the possibility that 6R-BH4 acts as a self-protecting factor for NO toxicity. In PC12 cells which have NOS, three-day culture with sodium nitroprusside (SNP) or NOC-12, NO generators, at 10–100 μM increased nitrite and nitrate concentrations in the culture medium and induced death of PC12 cells. Coadministration of 6R-BH4 (10 or 30 μM) with SNP or NOC-12 prevented cell death with reduction of nitrite and nitrate in the medium. Inhibition of 6R-BH4 synthesis by 2,4-diamino-6-hydroxypyrimidine (DAHP), an inhibitor for GTP cyclohydrolase I, decreased cellular 6R-BH4 content and viable cell number. The inhibiting effects of DAHP were restored by exogenous 6R-BH4. NOS activity, as estimated by nitrite concentrations in the medium, was unchanged by DAHP. Hypoxanthine and xanthine oxidase, which produce superoxide, mimicked the cell-protecting effect of 6R-BH4 which is reported to generate superoxide during its autoxidation. These results suggest that 6R-BH4 acts as a self-protecting factor for NO toxicity with generation of superoxide in NO-producing neurons. J. Neurosci. Res. 54:664–672, 1998. © 1998 Wiley-Liss, Inc. 相似文献
994.
In this study, we investigated a pattern-recognition technique based on an artificial neural network (ANN), which is called a massive training artificial neural network (MTANN), for reduction of false positives in computerized detection of lung nodules in low-dose computed tomography (CT) images. The MTANN consists of a modified multilayer ANN, which is capable of operating on image data directly. The MTANN is trained by use of a large number of subregions extracted from input images together with the teacher images containing the distribution for the "likelihood of being a nodule." The output image is obtained by scanning an input image with the MTANN. The distinction between a nodule and a non-nodule is made by use of a score which is defined from the output image of the trained MTANN. In order to eliminate various types of non-nodules, we extended the capability of a single MTANN, and developed a multiple MTANN (Multi-MTANN). The Multi-MTANN consists of plural MTANNs that are arranged in parallel. Each MTANN is trained by using the same nodules, but with a different type of non-nodule. Each MTANN acts as an expert for a specific type of non-nodule, e.g., five different MTANNs were trained to distinguish nodules from various-sized vessels; four other MTANNs were applied to eliminate some other opacities. The outputs of the MTANNs were combined by using the logical AND operation such that each of the trained MTANNs eliminated none of the nodules, but removed the specific type of non-nodule with which the MTANN was trained, and thus removed various types of non-nodules. The Multi-MTANN consisting of nine MTANNs was trained with 10 typical nodules and 10 non-nodules representing each of nine different non-nodule types (90 training non-nodules overall) in a training set. The trained Multi-MTANN was applied to the reduction of false positives reported by our current computerized scheme for lung nodule detection based on a database of 63 low-dose CT scans (1765 sections), which contained 71 confirmed nodules including 66 biopsy-confirmed primary cancers, from a lung cancer screening program. The Multi-MTANN was applied to 58 true positives (nodules from 54 patients) and 1726 false positives (non-nodules) reported by our current scheme in a validation test; these were different from the training set. The results indicated that 83% (1424/1726) of non-nodules were removed with a reduction of one true positive (nodule), i.e., a classification sensitivity of 98.3% (57 of 58 nodules). By using the Multi-MTANN, the false-positive rate of our current scheme was improved from 0.98 to 0.18 false positives per section (from 27.4 to 4.8 per patient) at an overall sensitivity of 80.3% (57/71). 相似文献
995.
996.
Comparison of the quality of temporal subtraction images obtained with manual and automated methods of digital chest radiography 总被引:2,自引:2,他引:0
Shigehiko Katsuragawa Hiroyuki Tagashira Qiang Li Heber MacMahon Kunio Doi 《Journal of digital imaging》1999,12(4):166-172
The authors have been developing a fully automated temporal subtraction scheme to assist radiologists in the detection of interval changes in digital chest radiographs. The temporal subtraction image is obtained by subtraction of a previous image from a current image. The authors' automated method includes not only image shift and rotation techniques but also a nonlinear geometric warping technique for reduction of misregistration artifacts in the subtraction image. However, a manual subtraction method that can be carried out only with image shift and rotation has been employed as a common clinical technique in angiography, and it might be clinically acceptable for detection of interval changes on chest radiographs as well. Therefore, the authors applied both the manual and automated temporal subtraction techniques to 181 digital chest radiographs, and compared the quality of the subtraction images obtained with the two methods. The numbers of clinically acceptable subtraction images were 147 (81.2%) and 176 (97.2%) for the manual and automated subtraction methods, respectively. The image quality of 148 (81.8%) subtraction images was improved by use of the automated method in comparison with the subtraction images obtained with the manual method. These results indicate that the automated method with the nonlinear warping technique can significantly reduce misregistration artifacts in comparison with the manual method. Therefore, the authors believe that the automated subtraction method is more useful for the detection of interval changes in digital chest radiographs. 相似文献
997.
Takio Yokoi Tsuneya Nakamura Kunio Kasugai Yasushi Yatabe Masahiro Fujita Makoto Kuroda Kayoko Akaza Chisa Nomura Eiji Hamajima Taizan Suchi Masao Seto Kazuo Hara Shigeo Nakamura 《Pathology international》1999,49(8):702-709
In the current study, we report eight cases with primary low-grade gastric mucosa-associated lymphoid tissue (MALT) lymphoma endoscopically characterized by polypoid lesions in order to highlight their clinicopathologic significance. Four patients were male, their ages ranging from 40 to 78 years old. The resected specimens revealed a histology of low-grade MALT lymphoma characterized by dense lymphocytic infiltration predominantly in the submucosa and a relatively monotonous proliferation of centrocyte-like cells with reactive follicles and infrequent lymphoepithelial lesions. The tumor cells were of CD5-, CD10-, CD20+, BCL2+ and cycline D1- phenotype, and showed a monoclonal rearrangement of immunoglobulin heavy chain genes in the five of six cases examined. Interestingly, Helicobacter pylori (H. pylori) was detected in three (37.5%) of the eight patients, which was significantly lower than previous reports. Two of the H. pylori-positive cases initially underwent H. pylori eradication, but showed no change in their lymphomas after the cure of H. pylori infection. The clinicopathologic findings of the present cases appeared to closely resemble those of colorectal MALT lymphoma with a polypoid appearance and few association of H. pylori infection in their pathogenesis. These gastric polypoid cases may merit separate consideration because of the therapeutic problems they pose. 相似文献
998.
Masayuki Akita MD PhD Nobuaki Yamasaki MD Taiichiro Miyake MD Kazuya Mimura MD Eri Maeda MD Tohru Nishimura MD Koichiro Abe MD Akihito Kozuki MD Kunio Yokoyama MD PhD Hiroaki Kominami MD PhD Tomohiro Tanaka MD PhD Manabu Takamatsu MD PhD Kunihiko Kaneda MD PhD 《Journal of surgical oncology》2020,121(7):1126-1131
999.
In this paper, we address a current problem in medical image processing,
the detection of colorectal cancer from colonoscopy videos. According to
worldwide cancer statistics, colorectal cancer is one of the most common cancers.
The process of screening and the removal of pre-cancerous cells from the large
intestine is a crucial task to date. The traditional manual process is dependent on
the expertise of the medical practitioner. In this paper, a two-stage classification is
proposed to detect colorectal cancer. In the first stage, frames of colonoscopy video
are extracted and are rated as significant if it contains a polyp, and these results are
then aggregated in a second stage to come to an overall decision concerning the
final classification of that frame to be neoplastic and non-neoplastic. In doing so,
a comparative study is being made by considering the applicability of deep
learning to perform this two-stage classification. The CNN models namely VGG16,
VGG19, Inception V3, Xception, GoogLeNet, ResNet50, ResNet100, DenseNet,
NASNetMobile, MobilenetV2, InceptionResNetV2 and fine-tuned version of each
model is evaluated. It is observed that the VGG19 model is the best deep learning
method for colonoscopy image diagnosis. 相似文献
1000.
Shiro Watanabe Takashi Kamei Ken Tanaka Kunio Kawasuji Tsuyoshi Yoshioka Masahiro Ohno 《Journal of ethnopharmacology》2009,125(2):203-206