全文获取类型
收费全文 | 2514篇 |
免费 | 154篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 29篇 |
儿科学 | 47篇 |
妇产科学 | 33篇 |
基础医学 | 250篇 |
口腔科学 | 37篇 |
临床医学 | 183篇 |
内科学 | 739篇 |
皮肤病学 | 66篇 |
神经病学 | 233篇 |
特种医学 | 39篇 |
外科学 | 414篇 |
综合类 | 23篇 |
预防医学 | 75篇 |
眼科学 | 34篇 |
药学 | 183篇 |
中国医学 | 8篇 |
肿瘤学 | 290篇 |
出版年
2022年 | 32篇 |
2021年 | 41篇 |
2020年 | 20篇 |
2019年 | 27篇 |
2018年 | 56篇 |
2017年 | 39篇 |
2016年 | 40篇 |
2015年 | 53篇 |
2014年 | 71篇 |
2013年 | 71篇 |
2012年 | 111篇 |
2011年 | 129篇 |
2010年 | 64篇 |
2009年 | 55篇 |
2008年 | 119篇 |
2007年 | 113篇 |
2006年 | 108篇 |
2005年 | 109篇 |
2004年 | 85篇 |
2003年 | 99篇 |
2002年 | 91篇 |
2001年 | 70篇 |
2000年 | 85篇 |
1999年 | 73篇 |
1998年 | 28篇 |
1997年 | 23篇 |
1994年 | 15篇 |
1993年 | 15篇 |
1992年 | 88篇 |
1991年 | 71篇 |
1990年 | 64篇 |
1989年 | 52篇 |
1988年 | 38篇 |
1987年 | 65篇 |
1986年 | 52篇 |
1985年 | 37篇 |
1984年 | 23篇 |
1983年 | 26篇 |
1982年 | 17篇 |
1981年 | 14篇 |
1980年 | 19篇 |
1979年 | 44篇 |
1978年 | 20篇 |
1977年 | 17篇 |
1975年 | 13篇 |
1972年 | 15篇 |
1971年 | 14篇 |
1970年 | 16篇 |
1969年 | 19篇 |
1968年 | 19篇 |
排序方式: 共有2683条查询结果,搜索用时 15 毫秒
91.
Tamai M Kawakami A Uetani M Fukushima A Arima K Fujikawa K Iwamoto N Aramaki T Kamachi M Nakamura H Ida H Origuchi T Aoyagi K Eguchi K 《Modern rheumatology / the Japan Rheumatism Association》2012,22(5):654-658
Objective
To explore whether synovitis and bone lesions in the wrists and finger joints visualized by plain magnetic resonance imaging (MRI)-based findings correspond exactly or not to those judged by gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA)-enhanced MRI-based findings.Methods
Magnetic resonance imaging of the wrists and finger joints of both hands were examined in 51 early-stage rheumatoid arthritis (RA) patients whose median disease duration from the onset of articular manifestations to entry was 5?months, by both plain (T1 and short-time inversion recovery images) and Gd-DTPA-enhanced MRI (post-contrast fat-suppressed T1-weighted images) simultaneously. We focused on 15 sites per hand, to examine the presence of synovitis and bone lesions (bone edema and bone erosion). Gd-DTPA-enhanced MRI-based findings were considered “true” lesions, and we evaluated the accuracy of plain MRI-based findings in comparison to Gd-DTPA-enhanced MRI-based findings.Results
Synovitis, judged by plain MRI-based findings, appeared as false-positive at pretty frequency; thus, the specificity, positive predictive value and accuracy of the findings were low. The rate of enhancement (E-rate) in false-positive synovitis sites was significantly low compared with true-positive synovitis sites where Gd-DTPA enhancement appears. In contrast to synovitis, the false-positivity of bone lesions, judged by plain MRI-based findings, was very low compared with Gd-DTPA-enhanced MRI-based findings.Conclusion
Synovitis judged by plain MRI-based findings is sometimes considered false-positive especially in sites where synovitis is mild. However, plain MRI is effective in identifying bone lesions in the wrist and finger joints in early-stage RA. 相似文献92.
G.‐D. Chen D. Shiu‐Chung Ko C.‐X. Wang J. Qiu M. Han L.‐Z. Chen 《American journal of transplantation》2013,13(5):1323-1326
Shortage of deceased donors is a severe problem in recent years in China especially in a culture in which brain death criteria is not widely accepted. Donation after cardiac death (DCD) has been reported to expand the donor pool despite higher rates of primary nonfunction (PNF) and delayed graft function (DGF) after transplantation. We collected 71 DCD kidney transplants performed at our hospital between February, 2007 and June, 2012 with aims to demonstrate the feasibility of DCD donation in China. All patients were followed up, and postoperative complications and graft loss were recorded. The PNF rate was 2.8%, and DGF rate was 28.2%. The 1‐ and 3‐year graft survival was 95.7% and 92.4%. In conclusion, graft survival of DCD kidney transplantation in China is excellent despite of higher rates of PNF and DGF after transplantation. 相似文献
93.
Kouhei Nishikawa Norihito Soga Kenichiro Ishii Manabu Kato Yoichi Iwamoto Yasuhide Hori Michiru Etoh Takeshi Ohkawara Tomomi Yamada Katsunori Uchida Hideaki Kise Kiminobu Arima Masaaki Narita Taizo Shiraishi Yoshiki Sugimura 《Urologic oncology》2013,31(6):787-795
ObjectivesTo investigate the presence of manserin in human prostate cancers and to correlate manserin expression with pathologic outcomes and progression-free survival.MethodsEighty-seven patients with recent prostate cancer were classified into 4 groups based on Gleason score, and manserin immunohistochemistry was correlated with Gleason sum grade. To investigate the validity of manserin as a prognostic factor, the Cox proportional hazards regression model was performed on 48 patients in our cohort with T3 or T4 prostate cancer who were initially treated with androgen deprivation therapy.ResultsThe manserin-positive rates of patients with Gleason sums of 6, 7, 8, and ≥9 were 0%, 20.0%, 35.0%, and 48.1%, respectively. Manserin-positive rates were positively correlated with Gleason sums (P = 0.0001). Median times to cancer progression in groups with (n = 8) and without (n = 40) manserin expression were 8 months and 28 months, respectively (P = 0.01). Univariate Cox analysis revealed that manserin expression, clinical stage T4, and high Gleason sum were significantly associated with progression. Multivariate analysis revealed that only 2 factors, manserin expression (hazard ratio (HR) 4.99, P = 0.01) and clinical stage T4 (HR 4.77, P = 0.03), were independent risk factors for progression.ConclusionsThis is the first report of manserin expression in human prostate cancers. Manserin may serve as a marker of prostate cancer progression. 相似文献
94.
Haruki Fujisawa Yoshihisa Sugimura Hiroshi Takagi Hiroyuki Mizoguchi Hideyuki Takeuchi Hisakazu Izumida Kohtaro Nakashima Hiroshi Ochiai Seiji Takeuchi Atsushi Kiyota Kazuya Fukumoto Shintaro Iwama Yoshiko Takagishi Yoshitaka Hayashi Hiroshi Arima Yukio Komatsu Yoshiharu Murata Yutaka Oiso 《Journal of the American Society of Nephrology : JASN》2016,27(3):766-780
Hyponatremia is the most common clinical electrolyte disorder. Once thought to be asymptomatic in response to adaptation by the brain, recent evidence suggests that chronic hyponatremia may be linked to attention deficits, gait disturbances, risk of falls, and cognitive impairments. Such neurologic defects are associated with a reduction in quality of life and may be a significant cause of mortality. However, because underlying diseases such as adrenal insufficiency, heart failure, liver cirrhosis, and cancer may also affect brain function, the contribution of hyponatremia alone to neurologic manifestations and the underlying mechanisms remain unclear. Using a syndrome of inappropriate secretion of antidiuretic hormone rat model, we show here that sustained reduction of serum sodium ion concentration induced gait disturbances; facilitated the extinction of a contextual fear memory; caused cognitive impairment in a novel object recognition test; and impaired long-term potentiation at hippocampal CA3–CA1 synapses. In vivo microdialysis revealed an elevated extracellular glutamate concentration in the hippocampus of chronically hyponatremic rats. A sustained low extracellular sodium ion concentration also decreased glutamate uptake by primary astrocyte cultures, suggesting an underlying mechanism of impaired long-term potentiation. Furthermore, gait and memory performances of corrected hyponatremic rats were equivalent to those of control rats. Thus, these results suggest chronic hyponatremia in humans may cause gait disturbance and cognitive impairment, but these abnormalities are reversible and careful correction of this condition may improve quality of life and reduce mortality. 相似文献
95.
BACKGROUND: There is an increased incidence of rare imprinting disorders associated with assisted reproduction technologies (ARTs). The sex-specific epigenetic modifications that are imposed during gametogenesis act as a primary imprint to distinguish maternal and paternal alleles. The most likely candidate for the gametic mark is DNA methylation. However, the timing of DNA methylation acquisition in adult oocytogenesis and the effects of superovulation are unknown. METHODS: We examined the maternal methylation of PEG1(MEST), LIT1(KCNQ1OT1) and ZAC(PLAGL1) and the paternal methylation of H19 in adult growing oocytes of humans and mice and compared them with the methylation status of mouse neonatal growing oocytes by using bisulphite sequencing. Furthermore, we examined the effects of superovulation in the human and mouse. RESULTS: Maternal methylation of these genes has already been initiated to some extent in adult human and mouse non-growing oocytes but not in mouse neonates. In addition, the methylation dynamics during adult human and mouse oocyte development changed more gradually than those during neonatal oocyte development. Furthermore, we found the demethylation of PEG1 in growing oocytes from some ART-treated infertile women and a gain in the methylation of H19. We also detected methylation changes in superovulated mice. CONCLUSION: Our studies in the human and mouse suggest that superovulation can lead to the production of oocytes without their correct primary imprint and highlight the need for more research into ARTs. 相似文献
96.
Functional determinants of NS2B for activation of Japanese encephalitis virus NS3 protease 总被引:2,自引:1,他引:1
Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus, causing severe central nerve system diseases without specific treatments. The NS2B-NS3 protease of flaviviruses mediates several cleavages on the flavivirus polyprotein, being believed to be a target for antiviral therapy. NS2B is the cofactor of the viral serine protease, correlating with stabilization and substrate recognition of the NS3 protease. In this study, we investigate the functional determinants in the JEV NS2B for the activation of the NS3 protease. Cis- and trans-cleavage assays of the deletions at the N-terminal of NS2B demonstrated that the NS2B residues Ser(46) to Ile(60) were the essential region required for both cis and trans activity of the NS3 protease. In addition, alanine substitution at the residues Trp53, Glu55, and Arg56 in NS2B significantly reduced the cis- and trans-cleavage activities of the NS3 protease. Sequence alignment and modeled structures suggested that functional determinants at the JEV NS2B residues Ser46 to Ile60, particularly in Trp53, Glu55 and Arg56 could play an important configuration required for the activity of the flavivirus NS3 protease. Our results might be useful for development of inhibitors that block the interaction between NS2B and NS3. 相似文献
97.
Arimura K Arima N Matsushita K Akimoto M Park CY Uozumi K Tei C 《Journal of clinical immunology》2007,27(2):145-151
Beh?et's disease (BD) is a systemic inflammatory disorder of unknown etiology, and rarely complicated with myelodysplastic syndrome (MDS). In the present study, we investigated the morphological myelodysplasia and apoptotic rate of bone marrow cells in 15 patients with BD in comparison with MDS patients. Morphological myelodysplasia of bone marrow cells was detected in 53.3% of BD, but none showed chromosomal abnormalities. The apoptotic rate in BD patients (26.1 +/- 8.4%) was significantly higher in normal controls (11.3 +/- 2.4%; p < 0.005) and significantly lower in patients with MDS (50.8 +/- 14.0%; p < 0.0001). These findings suggest that myelodysplasia in patients with BD is more frequent than expected, and possibly due to excess induction of apoptosis of bone marrow cells in BD. However, the rate of apoptotic bone marrow cells is lower than MDS, which may explain the slight peripheral cytopenia in BD, distinct from that in MDS. 相似文献
98.
Izuhara K Kanaji S Ohta S Arima K 《Rinsho byori. The Japanese journal of clinical pathology》2007,55(4):369-374
The incidence of allergic diseases has dramatically increased in recent decades in Japan; therefore, it is important to establish ways to diagnose allergic patients based on their pathogenesis and to treat them. Allergic diseases are complicated and diverse disorders in which various cells and mediators are involved; however, it is widely accepted that they are Th2-type inflammations triggered by the invasion of allergens. It is known that either IL-4 or IL-13, particularly the latter, has an important role in the pathogenesis of bronchial asthma among Th-2 type cytokines; however, it is unclear how IL-4 or IL-13 causes asthmatic phenotypes. We have been trying to address this question by using microarray analysis. We have recently found that periostin, identified as an IL-4/IL-13-inducible gene by microarray analysis, is a novel component of subepithelial fibrosis of bronchial asthma. This finding is important to demonstrate the significance of IL-4 and/or IL-13 as a therapeutic target to inhibit fibrosis in bronchial asthma. Furthermore, it is also important to establish a way to diagnose allergic patients in which IL-4 or IL-13 is dominantly involved, and to apply the developing IL-4/IL-13 inhibitors to these patients. In this article, we show how we are addressing this issue. 相似文献
99.
Hatem A. Elmezayen Hirohisa Okabe Yoshifumi Baba Toshihiko Yusa Rumi Itoyama Yosuke Nakao Takanobu Yamao Naoki Umzaki Masayo Tsukamoto Yuki Kitano Tatsunori Miyata Kota Arima Hiromitsu Hayashi Katsunori Imai Akira Chikamoto Yo-ichi Yamashita Hideo Baba 《Surgery today》2020,50(6):569-576
Programmed death ligand 1 (PD-L1) is a key target for the treatment of several malignancies. The present study was conducted to clarify the role of serum PD-L1 in hepatocellular carcinoma (HCC). Serum PD-L1 (sPD-L1) was examined by an enzyme-linked immunosorbent assay in 153 patients with HCC who underwent curative hepatectomy at Kumamoto University in 2011–2016. The expression of PD-L1 in tissue (tPD-L1) was investigated by immunohistochemistry. The clinical roles of the PD-L1 expression in both serum and tissue were examined. The sPD-L1 was significantly elevated in HCC patients compared to patients without any malignant or inflammatory disease (234 vs. 93 pg/mL, p < 0.0001). The percentage of the tPD-L1-positive area (%tPD-L1) in the background liver was significantly higher than in the tumor (1.52% vs. 0.48%, p < 0.0001). The %tPD-L1 in the background liver but not in the tumor was significantly correlated with the sPD-L1 level (p = 0.0079). The sPD-L1, %tPD-L1 in the tumor, and %tPD-L1 in the background liver were not correlated with the overall survival after surgery. PD-L1-expressing cells in the background liver, but not in the tumor tissue, appeared to contribute to the sPD-L1 level. The sPD-L1 level may thus not indicate the tumor burden in patients with HCC. 相似文献
100.
Masayuki Itoh Yuji Iwasaki Kohsaku Ohno Takehiko Inoue Masaharu Hayashi Shuichi Ito Tetsuo Matsuzaka Shuhei Ide Masataka Arima 《Brain & development》2014
Aim: We have never known any epidemiological study of Arima syndrome since it was first described in 1971. To investigate the number of Arima syndrome patients and clarify the clinical differences between Arima syndrome and Joubert syndrome, we performed the first nationwide survey of Arima syndrome, and herein report its results. Furthermore, we revised the diagnostic criteria for Arima syndrome. Methods: As a primary survey, we sent out self-administered questionnaires to most of the Japanese hospitals with a pediatric clinic, and facilities for persons with severe motor and intellectual disabilities, inquiring as to the number of patients having symptoms of Arima syndrome, including severe psychomotor delay, agenesis or hypoplasia of cerebellar vermis, renal dysfunction, visual dysfunction and with or without ptosis-like appearance. Next, as the second survey, we sent out detailed clinical questionnaires to the institutes having patients with two or more typical symptoms. Results: The response rate of the primary survey was 72.7% of hospitals with pediatric clinic, 63.5% of national hospitals and 66.7% of municipal and private facilities. The number of patients with 5 typical symptoms was 13 and that with 2–4 symptoms was 32. The response rate of the secondary survey was 52% (23 patients). After reviewing clinical features of 23 patients, we identified 7 Arima syndrome patients and 16 Joubert syndrome patients. Progressive renal dysfunction was noticed in all Arima syndrome patients, but in 33% of those with Joubert syndrome. Conclusion: It is sometimes difficult to distinguish Arima syndrome from Joubert syndrome. Some clinicians described a patient with Joubert syndrome and its complications of visual dysfunction and renal dysfunction, whose current diagnosis was Arima syndrome. Thus, the diagnosis of the two syndromes may be confused. Here, we revised the diagnostic criteria for Arima syndrome. 相似文献