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71.
Yamada T Murakami Y Muto M Okada T Okamoto M Toyama J Yoshida Y Tsuboi N Ito T Kondo T Inden Y Hirai M Murohara T 《Journal of cardiovascular electrophysiology》2004,15(7):745-751
INTRODUCTION: The right pulmonary veins (RPVs) and posterior wall of the right atrium (PRA) are anatomically located adjacent to each other. The aim of this study was to demonstrate the electrophysiologic characteristics of atrial tachycardia (AT) originating from the PRA or RPVs. METHODS AND RESULTS: A total of 26 consecutive patients with AT originating from the RPVs or PRA underwent detailed atrial endocardial mapping and successful radiofrequency catheter ablation. Eight foci were found in the PRA and 18 foci in the RPVs. Analysis of P wave configuration showed that lead V1 was the most helpful in distinguishing the AT foci between these two sites. In all cases, double potential (DP) configurations were recorded from several electrodes of a multielectrode catheter placed in the PRA, and the first DP component (FP) was the earliest potential recorded from the right atrium during the tachycardia. The amplitude of the FP was higher than that of the second DP component (SP) for AT foci originating in the PRA, whereas the reverse occurred for those in the RPV. The activation sequence of the FP was from superior to inferior for the AT foci in the superior RPV, whereas the reverse occurred for the AT foci in the inferior RPV. CONCLUSION: P wave configuration in lead V1 is helpful in distinguishing AT foci between those originating in the PRA and RPVs. The DPs obtained from the PRA can be useful in predicting whether AT foci originate from the PRA or RPVs. 相似文献
72.
Makoto Seki Akio Yanagisawa Eiji Ninomiya Yasuro Ninomiya Hirotoshi Ohta Akio Saiura Junji Yamamoto Toshiharu Yamaguchi Akiko Aruga Keiko Yamada Koichi Takano Rikiya Fujita Masayuki Ikeda Keiko Sasaki Yo Kato 《Journal of hepato-biliary-pancreatic sciences》2005,12(3):254-262
Background/Purpose
Between 1988 and 2003, 38 patients underwent biliary resection for pancreaticobiliary maljunction (PBM). We reviewed the histopathologic findings for the surgically resected specimens to compare the clinical and pathologic features and assess the relationship between changes in the background biliary epithelium and the development of neoplasms.Methods
Papillary hyperplasia (PHP) seen in the biliary epithelium of patients with PBM, was classified into grades 0–III in the gallbladder and grades 0–II in the extrahepatic bile duct, according to the extent, and was assessed for links with tumors in the same specimens.Results
The incidence of gallbladder carcinoma was 13/21 in grades I–II, versus 0/16 in grade III, while the incidence of bile duct carcinoma was 4/20 in grade I versus 0/5 in grade II. Furthermore, these incidences for patients below age 50 years and age 50 or older were 1/18 versus 12/20, and 0/14 versus 6/17, respectively.Conclusions
PHP of the biliary epithelium in PBM patients is an important precursor lesion, especially for gallbladder cancer, and the risk becomes greater with age, regardless of the type of pancreatobiliary junction (PBJ) and its location in the biliary tract. 相似文献73.
Muneo Yoshibayashi MD Nagara Tamaki MD Kenya Nishioka MD Masahiko Matsumura MD Tadashi Ueda MD Shinji Temma MD Yoshiharu Yonekura MD Keiji Yamashita MD Junji Konishi MD Haruki Mikawa MD 《The American journal of cardiology》1991,68(17):1638-1645
To clarify the significance of newly appearing abnormal Q waves and their disappearance in patients with Kawasaki disease, regional myocardial perfusion and glucose metabolism at rest in the fasting condition were assessed by positron emission tomography (PET) with 13N-ammonia and 18F-fluorodeoxyglucose (FDG), and regional wall motion by left ventriculography in regions with persistent and transient abnormal Q waves in 14 patients. PET identified 3 groups of abnormal myocardial segments: segments with hypoperfusion without increased FDG uptake, those with hypoperfusion and increased FDG uptake, and those with normal perfusion and increased FDG uptake. Almost all the segments with persistent or transient abnormal Q waves had abnormal PET findings. PET demonstrated evidence of metabolic activity in 57% of segments with persistent abnormal Q waves and 67% of those with transient abnormal Q waves. Regional wall motion, scored from 0 (normal) to 4 (dyskinesia), was not significantly different between segments with persistent and transient abnormal Q waves (2.3 ± 1.3 vs 2.2 ± 1.2). The persistence of abnormal Q waves on serial electrocardiograms was significantly shorter in metabolically active than in inactive segments (19 ± 17 vs 92 ± 27 months). In conclusion, in patients with Kawasaki disease, the new appearance of abnormal Q waves is a reliable clue to the presence of ischemic myocardial injury and a high proportion of them are associated with metabolically active myocardial regions. The disappearance of abnormal Q waves does not necessarily mean the normalization of regional myocardial perfusion, metabolism or function, and their early disappearance may imply “viability” in the associated myocardial region. 相似文献
74.
Hiraga J Kondoh Y Taniguchi H Kinoshita T Naoe T 《International journal of hematology》2005,81(2):169-170
International Journal of Hematology - 相似文献
75.
76.
Yoshikazu Uchiyama Akiko Abe Chisako Muramatsu Takeshi Hara Junji Shiraishi Hiroshi Fujita 《Journal of digital imaging》2015,28(1):116-122
Detection of lacunar infarcts is important because their presence indicates an increased risk of severe cerebral infarction. However, accurate identification is often hindered by the difficulty in distinguishing between lacunar infarcts and enlarged Virchow-Robin spaces. Therefore, we developed a computer-aided detection (CAD) scheme for the detection of lacunar infarcts. Although our previous CAD method indicated a sensitivity of 96.8 % with 0.71 false positives (FPs) per slice, further reduction of FPs remained an issue for the clinical application. Thus, the purpose of this study is to improve our CAD scheme by using template matching in the eigenspace. Conventional template matching is useful for the reduction of FPs, but it has the following two pitfalls: (1) It needs to maintain a large number of templates to improve the detection performance, and (2) calculation of the cross-correlation coefficient with these templates is time consuming. To solve these problems, we used template matching in the lower dimension space made by a principal component analysis. Our database comprised 1,143 T1- and T2-weighted images obtained from 132 patients. The proposed method was evaluated by using twofold cross-validation. By using this method, 34.1 % of FPs was eliminated compared with our previous method. The final performance indicated that the sensitivity of the detection of lacunar infarcts was 96.8 % with 0.47 FPs per slice. Therefore, the modified CAD scheme could improve FP rate without a significant reduction in the true positive rate. 相似文献
77.
Junji Kato Yoshihiro Mogi Yutaka Kohgo Rishu Takimoto Masayoshi Kobune Hiroyuki Hisai Tokiko Nakamura Kohichi Takada Yoshiro Niitsu 《Journal of gastroenterology》1998,33(6):855-859
Blood levels of inflammatory-related cytokines, including interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α, are
elevated in patients with alcoholic liver diseases. We investigated the effects of these cytokines and ethanol on the expression
of hepatic asialoglycoprotein receptors (AGPRs) in a human hepatoblastoma cell line, HepG2. An [125I]-asialo-orosomucoid binding assay showed significant increases in surface AGPR numbers in HepG2 cells by treatment with
IL-1β, IL-6, and TNF-α, to levels which were approximately 130% of the values in untreated control cells. However, the enhanced
AGPR numbers induced by treatment with these cytokines were markedly suppressed, to 70%–80% of the number in the untreated
cells, by treatment with ethanol. Immunological detection of AGPR with a specific antibody demonstrated that the modulation
of surface AGPR numbers was correlated with the cellular expression levels of AGPR. These results suggest that, although IL-1β,
IL-6, and TNF-α stimulate the synthesis of hepatic AGPR, ethanol suppresses the expression of AGPR augmented by these cytokines.
This leads to an increase in serum asialo-orosomucoid levels caused by the disordered catabolism mediated by AGPR in patients
with alcoholic liver disease.
(Received Dec. 5, 1997; accepted May 22, 1998) 相似文献
78.
Usefulness of measurement of reticulated platelets for diagnosis of idiopathic thrombocytopenic purpura. 总被引:2,自引:0,他引:2
Miho Sakakura Hideo Wada Yasunori Abe Junji Nishioka Hiroaki Tomatsu Yukio Hamaguchi Shinichiro Oguni Hiroshi Shiku Tsutomu Nobori 《Clinical and applied thrombosis/hemostasis》2005,11(3):253-261
Reticulated platelets (RP) and large platelets (LP) were measured by an automated hematology analyzer (modified R-2000) in 287 healthy volunteers and 131 patients with thrombocytopenia or thrombocytosis. RP was significantly higher in patients with idiopathic thrombocytopenic purpura (ITP), especially in active phase, while RP was markedly lower in patients with essential thrombocytosis (ET) or chronic myelocytic leukemia (CML). LP was significantly higher in patients with ITP, especially in active phase, while LP was markedly lower in patients with aplastic anemia (AA), ET, or CML. In ITP, RP and LP were significantly higher in patients positive for anti-glycoprotein (Gp) IIb/IIIa antibody. RP and LP were poorly correlated with platelet-associated IgG (PAIgG). RP and LP were poorly correlated with plasma thrombopoietin levels, and negatively correlated with platelet count. These results show that RP reflects the pathology of thrombocytopenic disorders, and that measurement of RP is useful for the differential diagnosis and analysis of platelet kinetics. 相似文献
79.
Nobushige Takahashi Hidetoshi Takahashi Osamu Takahashi Ryosuke Ushijima Rie Umebayashi Junji Nishikawa Yasutomo Okajima 《PM & R》2018,10(2):168-174
Background
Spasticity is a common sequela of upper motor neuron pathology, such as cerebrovascular diseases and cerebral palsy. Intervention for spasticity of the ankle plantarflexors in physical therapy may include tone-inhibiting casting and/or orthoses for the ankle and foot. However, the physiological mechanism of tone reduction by such orthoses remains unclarified.Objective
To investigate the electrophysiologic effects of tone-inhibiting insoles in stroke subjects with hemiparesis by measuring changes in reciprocal Ia inhibition (RI) in the ankle plantarflexor.Design
An interventional before–after study.Setting
Acute stroke unit or ambulatory rehabilitation clinic of a university hospital in Japan.Participants
Ten subjects (47-84 years) with hemiparesis and 10 healthy male control subjects (31-59 years) were recruited.Methods
RI of the spastic soleus in response to the electrical stimulation of the deep peroneal nerve was evaluated by stimulus-locked averaging of rectified electromyography (EMG) of the soleus while subjects were standing.Main Outcome Measurements
The magnitude of RI, defined as the ratio of the lowest to the baseline amplitude of the rectified EMG at approximately 40 milliseconds after stimulation, was measured while subjects were standing with and without the tone-inhibiting insole on the hemiparesis side.Results
Enhancement of EMG reduction with the tone-inhibiting insole was significant (P < .05) in the subjects with hemiparesis, whereas no significant changes were found in controls.Conclusion
Tone-inhibiting insoles enhanced RI of the soleus in subjects after stroke, which might enhance standing stability by reducing unfavorable ankle plantarflexion tone.Level of Evidence
III 相似文献80.
Kiyomi Morita Akira Honda Junji Koya Kazuhiro Toyama Mahoko Ikeda Yoshiki Misawa Shu Okugawa Fumihiko Nakamura Kyoji Moriya Mineo Kurokawa 《Journal of infection and chemotherapy》2018,24(7):576-578
Bloodstream infection with non-Candida albicans Candida species is one of the serious complications among patients with hematological malignancies who receive long-term prophylactic antifungal agents. Here we describe three cases of Candida fermentati (C. fermentati) candidemia after allogeneic stem cell transplantation for hematological malignancies. Case 1 is fluconazole-breakthrough C. fermentati fungemia, which was well controlled with liposomal amphotericin B. Case 2 and 3 were caspofungin-breakthrough C. fermentati fungemia. In case 2, blood culture turned negative for Candida responding to liposomal amphotericin B. Although in vitro susceptibility data for the isolated pathogen suggested the efficacy of both caspofungin and liposomal amphotericin B in all three cases, clinically liposomal amphotericin B seemed to have been more effective for eradication of the pathogen from blood stream. C. fermentati needs to be considered as a possible cause for breakthrough candidemia among post-transplant patients with prolonged antifungal prophylaxis. Discrepancy between in vitro and in vivo susceptibility to antifungals, especially to echinocandins, might provide a clue for the optimal choice of antifungals for C. fermentati infections. 相似文献