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53.
Up-regulation of transferrin receptor 1 in chronic hepatitis C: Implication in excess hepatic iron accumulation. 总被引:3,自引:0,他引:3
Hiroyuki Saito Yoshinori Fujimoto Takaaki Ohtake Yasuaki Suzuki Shinobu Sakurai Yayoi Hosoki Katsuya Ikuta Yoshihiro Torimoto Yutaka Kohgo 《Hepatology research》2005,31(4):203-210
BACKGROUND/AIMS:: To clarify the mechanism of excess hepatic iron accumulation in chronic hepatitis C, we investigated the expressions of transferrin receptor 1 and divalent metal transporter 1 in hepatocytes, both of which are involved in cellular iron uptake, in relation to the degree of hepatic iron accumulation and hepatic fibrosis by immunohistochemistrical study. METHODS:: Forty-six hepatic tissues with chronic hepatitis C and five normal hepatic tissues were examined. Chemical detection of hepatic iron accumulation was performed by Perl's Prussian blue stain. The immunohistochemistrical study was performed by avidin-biotin complex method with alkaline phosphatase. RESULTS:: In chronic hepatitis C: (1) Hepatic iron accumulation was significantly increased in relation to the advance of the fibrosis. (2) Divalent metal transporter 1 decreased significantly in relation to the advance of hepatic fibrosis. (3) Transferrin receptor 1 expression was always detected, although not in normal hepatic tissues; there was no relation between expression levels and the degree of hepatic fibrosis. CONCLUSIONS:: These data demonstrated that the transferrin receptor 1 expression was up-regulated irrespective of the degree of hepatic iron accumulation, suggesting that the up-regulation of transferrin receptor 1 might act as one of the key mechanisms implicated in the accumulation of hepatic iron in chronic hepatitis C. 相似文献
54.
Morishita E Sekiya A Hayashi T Kadohira Y Maekawa M Yamazaki M Asakura H Nakao S Ohtake S 《International journal of hematology》2008,88(3):272-277
Previous studies have found markedly elevated serum concentrations of proinflammatory cytokines in patients with Graves’ disease
(GD). We investigated the role of macrophage colony-stimulating factor (M-CSF) in GD. We assayed concentrations of M-CSF in
sera from 32 patients with GD (25 untreated; 7 receiving thiamazole therapy). We also studied 32 age-matched healthy subjects
as controls. Relationships between serum M-CSF and both thyroid state and serum lipids were examined. Moreover, to examine
the effect of thyroid hormone alone on serum M-CSF, T3 was administered orally to normal subjects. Serum concentrations of
M-CSF in GD patients who were hyperthyroid were significantly increased compared with GD patients who were euthyroid (P < 0.05) and control subjects (P < 0.0001). Serum M-CSF concentrations correlated closely with T3 levels in patients (r = 0.51, P < 0.005). Serial measurement of five individual patients revealed that serum concentrations of M-CSF were significantly decreased
(P < 0.05), reaching normal control values upon attainment of euthyroidism. Furthermore, oral T3 administered to 15 volunteers
for 7 days produced significant increases in serum levels of M-CSF (P < 0.05). The close correlation between serum M-CSF and serum thyroid hormone levels suggests that high circulating levels
of thyroid hormones may directly or indirectly potentiate the production of M-CSF in patients with GD. 相似文献
55.
Yamazaki T Asanoi H Ueno H Yamada K Takagawa J Kameyama T Hirai T Nozawa T Inoue H 《Clinical and experimental hypertension (New York, N.Y. : 1993)》2005,27(2-3):241-249
The present study was designed to develop a method to continuously measure Holter electrocardiogram (ECG) and physical activity in terms of metabolic costs to examine circadian dynamics of RR intervals and physical activity in patients with heart failure. A total of 7 healthy subjects and 3 heart failure patients performed cardiopulmonary exercise test using four-stage graded treadmill walking at 0% grade to examine whether the acceleration signals in the vertical direction could reflect actual body energy expenditure during physical activity. Then, using this new method, 24-hr monitorings of ECG and physical activity were performed in 24 inpatients with heart failure while they were allowed to walk around freely. Our results showed the integral of rectified acceleration signals was closely correlated with actual metabolic cost in all subjects. Instantaneous changes in heart rate were quite concordant with physical activity. As compared with the asymptomatic patients (n = 12), the symptomatic patients (n = 12) had lower energy expenditure during 8-hr daytime periods but higher mean heart rate. Furthermore, a more prominent ultradian rhythm of circadian changes in heart rate and physical activity was found in 50% of all subjects studied. The simultaneous analysis of Holter ECG and physical activity as the same time series revealed that in patients with heart failure, sympathovagal balance shifted toward sympathotonic conditions and their physical activity could become subject to intrinsic ultradian dynamics of body's homeostasis. 相似文献
56.
Narita I Goto S Saito N Song J Ajiro J Sato F Saga D Kondo D Akazawa K Sakatsume M Gejyo F 《Hypertension》2003,42(3):304-309
An interaction effect between the angiotensin-converting enzyme insertion/deletion (ACE I/D) and alpha-adducin (ADD1) Gly460Trp polymorphisms (G460W) on blood pressure regulation has recently been suggested, although its significance in the prognosis of renal function in IgA nephropathy (IgAN) has not been fully investigated. Therefore, we evaluated the clinical manifestations and renal prognosis in 276 Japanese patients with histologically proven IgAN with respect to their ACE I/D and ADD1 G460W polymorphisms. The prognosis of renal function was analyzed by Kaplan-Meier survival curves and multivariate Cox proportional-hazards regression models. Baseline data, including blood pressures, proteinuria, renal function, and incidence of hypertension, were similar for the different genotypes of ACE and ADD1. The individual genotypes taken alone were not associated with the progression of renal dysfunction. However, renal survival of patients with the 460WW polymorphism of ADD1 was significantly worse within the group with the II genotype of ACE (Kaplan-Meier, log rank test; chi2=6.062, P=0.0138) but not for those with other ACE genotypes. In the Cox proportional-hazards regression model with adjustment for clinical risk factors, including hypertension, proteinuria, and no administration of an angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers, the 460WW variant of ADD1 was a highly significant and independent risk factor only for patients with the ACE II genotype, with a hazard ratio of 3.65 (P=0.0016), but not for those with other ACE genotypes (hazard ratio=0.65, P=0.2902). These findings suggest an interaction between ACE and ADD1 polymorphisms not only on blood pressure regulation but also on the progression of renal dysfunction in patients with IgAN. 相似文献
57.
Mayu Yazaki Takeru Nabeta Takayuki Inomata Kenji Maemura Takumi Oki Teppei Fujita Yuki Ikeda Shunsuke Ishii Takashi Naruke Yusuke Inoue Junya Ako 《Clinical cardiology》2021,44(2):222
BackgroundClinical significance of left atrial (LA) function and geometry in patients with dilated cardiomyopathy (DCM) remains uncertain.HypothesisLA geometric parameters assessed by cardiac magnetic resonance (CMR) predict the prognosis in patients with DCM.MethodsThe present study included patients with DCM and sinus rhythm who underwent CMR between December 2007 and April 2018. LA volume was measured using CMR. LA sphericity index was computed as the ratio of the measured maximum LA volume by the volume of a sphere with maximum LA length diameter.ResultsWe included 255 patients in this study. During the mean follow‐up of 3.92 years, hospitalization for HF occurred in 37 patients. The LA sphericity index was significantly higher in patients with hospitalization for HF than in those without (0.78 ± 0.35 vs. 0.58 ± 0.18, p < .001). Multivariable Cox regression analysis identified a higher LA sphericity index as an independent predictor of hospitalization for HF. Patients were categorized based on the median of LA sphericity index. The Kaplan–Meier curve showed that patients with a high LA sphericity index (≥0.57) had a significantly higher risk of hospitalization for HF than those with a low LA sphericity index (<0.57).ConclusionLA sphericity index was an independent predictor of hospitalization for HF. Assessment of LA geometric parameters might be useful for risk stratification in patients with DCM. 相似文献
58.
Ryosuke Arakawa Lars Farde Junya Matsumoto Naoki Kanegawa Igor Yakushev Kai-Chun Yang Akihiro Takano 《Molecular imaging and biology》2018,20(2):183-187
Purpose
Positron emission tomography (PET) in non-human primates (NHP) is commonly performed under anesthesia, with sevoflurane being a widely used inhaled anesthetic. PET measurement in NHP can be repeated, and a difference in radioligand kinetics has previously been observed between the first and second PET measurement on the same day using sevoflurane anesthesia. In this study, we evaluated the effect of prolonged sevoflurane anesthesia on kinetics and binding potential (BPND) of [11C]raclopride in NHP.Procedures
Three cynomolgus monkeys underwent two to three PET measurements with [11C]raclopride under continuous sevoflurane anesthesia on the same day. The concentration of sevoflurane was adjusted according to the general conditions and safety parameters of the NHP. Time to peak (TTP) radioactivity in the striatum was estimated from time-activity curves (TACs). The BPND in the striatum was calculated by the simplified reference tissue model using the cerebellum as reference region.Results
In each NHP, the TTP became shorter in the later PET measurements than in the first one. Across all measurements (n = 8), concentration of sevoflurane correlated with TTP (Spearman’s ρ = ? 0.79, p = 0.03), but not with BPND (ρ = ? 0.25, p = 0.55).Conclusions
These data suggest that sevoflurane affects the shape of TACs but has no evident effect on BPND in consecutive PET measurements.59.
Junya Sato Hiroyuki Matsubayashi Hirotoshi Ishiwatari Tatsunori Satoh Junichi Kaneko Kazuma Ishikawa Masao Yoshida Kohei Takizawa Yohei Yabuuchi Yoshihiro Kishida Kenichiro Imai Kinichi Hotta Katsuhiko Uesaka Keiko Sasaki Hiroyuki Ono 《Internal medicine (Tokyo, Japan)》2021,60(5):739
We herein report a unique form of autoimmune pancreatitis (AIP) spreading along the main pancreatic duct (MPD). A 70-year-old man was referred for a small lesion at the pancreatic neck, accompanying an adjacent cyst and dilated upstream MPD. Four years earlier, health checkup images had shown a pancreatic cyst but no mass lesion. Endoscopic ultrasonography showed a contrast-enhanced, tumorous lesion, mainly occupying the MPD. With a preoperative diagnosis of ductal neoplasms mainly spreading in the MPD, Whipple''s resection was performed. The resected specimens showed MPD periductitis with IgG4-related pathology, indicating type 1 AIP. Clinicians should practice caution concerning the various AIP forms. 相似文献
60.
Junya Makiyama Yoshitaka Imaizumi Haruka Watanabe Machiko Fujioka Masahiko Chiwata Hideaki Kitanosono Jun Nakashima Yasushi Miyazaki Shinichiro Yoshida 《Internal medicine (Tokyo, Japan)》2021,60(5):709
Objective Classic Hodgkin lymphoma (CHL) has been regarded as a curable disease when treated appropriately, especially in younger patients, and ABVD (doxorubicin, bleomycin, vinblastine, and dacarbazine) has been regarded as the standard regimen. However, a relatively poor prognosis has been reported in older patients with CHL, and the efficacy and tolerability of the ABVD regimen has not been fully elucidated. We retrospectively investigated the outcomes in patients with CHL treated with ABVD at our institute. Methods Twenty-five patients were evaluated; 14 were ≤60 years of age, and 11 were >60 years of age (older group). Results The ABVD doses were reduced in all patients in the older group; the median average relative dose intensity was 0.58. In the older group, the 5-year overall survival (OS) and median OS were 100% and not reached, respectively, for patients with early-stage CHL and 66.7% and not reached, respectively, for those with advanced-stage CHL. No patients died of CHL, and only one treatment-related death was observed in the older group. Conclusion ABVD with dose attenuation may represent a feasible and effective strategy for the treatment of older patients with CHL in clinical practice, particularly in those with early-stage disease, although the optimal degree of attenuation remains unclear. 相似文献