全文获取类型
收费全文 | 8404篇 |
免费 | 408篇 |
国内免费 | 50篇 |
专业分类
耳鼻咽喉 | 79篇 |
儿科学 | 153篇 |
妇产科学 | 119篇 |
基础医学 | 1139篇 |
口腔科学 | 274篇 |
临床医学 | 579篇 |
内科学 | 2250篇 |
皮肤病学 | 112篇 |
神经病学 | 483篇 |
特种医学 | 272篇 |
外科学 | 1407篇 |
综合类 | 31篇 |
预防医学 | 232篇 |
眼科学 | 128篇 |
药学 | 585篇 |
中国医学 | 10篇 |
肿瘤学 | 1009篇 |
出版年
2023年 | 58篇 |
2022年 | 129篇 |
2021年 | 210篇 |
2020年 | 105篇 |
2019年 | 161篇 |
2018年 | 175篇 |
2017年 | 132篇 |
2016年 | 146篇 |
2015年 | 156篇 |
2014年 | 195篇 |
2013年 | 234篇 |
2012年 | 358篇 |
2011年 | 396篇 |
2010年 | 218篇 |
2009年 | 187篇 |
2008年 | 347篇 |
2007年 | 373篇 |
2006年 | 301篇 |
2005年 | 348篇 |
2004年 | 335篇 |
2003年 | 318篇 |
2002年 | 320篇 |
2001年 | 314篇 |
2000年 | 279篇 |
1999年 | 255篇 |
1998年 | 108篇 |
1997年 | 72篇 |
1996年 | 81篇 |
1995年 | 67篇 |
1994年 | 62篇 |
1993年 | 68篇 |
1992年 | 238篇 |
1991年 | 215篇 |
1990年 | 203篇 |
1989年 | 210篇 |
1988年 | 167篇 |
1987年 | 162篇 |
1986年 | 172篇 |
1985年 | 122篇 |
1984年 | 95篇 |
1983年 | 95篇 |
1982年 | 52篇 |
1979年 | 64篇 |
1978年 | 53篇 |
1977年 | 44篇 |
1975年 | 40篇 |
1974年 | 50篇 |
1973年 | 47篇 |
1972年 | 45篇 |
1971年 | 40篇 |
排序方式: 共有8862条查询结果,搜索用时 15 毫秒
991.
Iwamoto N Sato N Nishida M Hashimoto T Kobayashi H Yamasaki S Ono T Nishimura M Tokoro T Sakoda C Murakawa M Okino K Okamoto Y Imai R Adachi N Ninomiya K Mabuchi H Koyama M Nakanouchi T Iseki K 《Journal of nephrology》2012,25(5):755-763
Background and aims: To compare the prognosis of chronic hemodialysis patients with or without parathyroidectomy. Methods: Among 158 chronic hemodialysis patients who underwent total parathyroidectomy between July 1998 and April 2009, 88 patients were matched with 88 controls for sex, age, underlying disease and prior dialysis history. Then a retrospective evaluation of their prognosis was performed over a median observation period of 4.41 years. Results: The overall survival rate was 90.4% in the parathyroidectomy group and 67.4% in the control group. The cardiovascular death-free survival rate was 94.6% in the parathyroidectomy group and 76.3% in the control group. During observation, intact parathyroid hormone was measured every 6 months, and its average serum level was 37 ± 92 ng/L in the total parathyroidectomy group versus 274 ± 233 ng/L in the control group (p=0.0001). The total parathyroidectomy group had a significantly lower corrected calcium level and higher serum albumin level. Multivariate analysis revealed that parathyroidectomy, atrial fibrillation and serum albumin were significant factors for both total and cardiovascular mortality. Conclusion: Total parathyroidectomy was associated with better survival, probably due to decreased cardiovascular mortality. 相似文献
992.
993.
Daiki Hashimoto Mizuki Kajimoto Yuko Ueda Taiju Hyuga Kota Fujimoto Saaya Inoue Kentaro Suzuki Tomoya Kataoka Kazunori Kimura Gen Yamada 《Reproductive Medicine and Biology》2021,20(2):199-207
PurposeErectile dysfunction (ED) is one of the increasing diseases with aging society. The basis of ED derived from local penile abnormality is poorly understood because of the complex three‐dimensional (3D) distribution of sinusoids in corpus cavernosum (CC). Understanding the 3D histological structure of penis is thus necessary. Analyses on the status of regulatory signals for such abnormality are also performed.MethodsTo analyze the 3D structure of sinusoid, 3D reconstruction from serial sections of murine CC were performed. Histological analyses between young (2 months old) and aged (14 months old) CC were performed. As for chondrogenic signaling status of aged CC, SOX9 and RBPJK staining was examined.ResultsSinusoids prominently developed in the outer regions of CC adjacent to tunica albuginea. Aged CC samples contained ectopic chondrocytes in such regions. Associating with the appearance of chondrocytes, the expression of SOX9, chondrogenic regulator, was upregulated. The expression of RBPJK, one of the Notch signal regulators, was downregulated in the aged CC.ConclusionsProminent sinusoids distribute in the outer region of CC which may possess important roles for erection. A possibility of ectopic chondrogenesis induced by alteration of SOX9/Notch signaling with aging is indicated. 相似文献
994.
Hirokazu Komatsu Satoshi Imamura Tomoki Shimizu Yuya Tsunoda Tsuyoshi Ito Jin Imai Shuichi Nagakubo Yuichi Morohoshi Yuriko Fujita 《Clinical journal of gastroenterology》2012,5(1):35-41
A 65-year-old man suffered from advanced hepatocellular carcinoma in the right lobe of the liver, for which he received no
treatment. His serum was positive for hepatitis C antibody. In spite of his poor prognosis, he remained in good clinical condition
and at 6-month follow-up the tumor had regressed without specific treatment, as assessed both radiologically and from a decrease
of a previously elevated serum tumor marker level (1st regression). The tumor regrew in size, but at 23-month follow-up could
no longer be visualized radiologically (2nd regression). A follow-up computed tomography (CT) scan did not show any relapse
of hepatocellular carcinoma until March 2005. At that time, a new lesion had developed in the caudate lobe and tumor size
had increased to ≥10 cm in diameter, and in June 2006 had invaded the portal vein and inferior vena cava. Afterwards, the
tumor lesion gradually decreased again. In June 2007, a CT scan showed a further reduction of tumor size (3rd regression).
Here, we report a rare case of spontaneous regression of hepatocellular carcinoma in which spontaneous regression and recurrence
were repeated 3 times. 相似文献
995.
Kawazoe Y Sugita S Keino H Yamada Y Imai A Horie S Mochizuki M 《Experimental eye research》2012,94(1):32-40
Primary cultured retinal pigment epithelial (RPE) cells can convert T cells into T regulatory cells (Tregs) through inhibitory factor(s) including transforming growth factor β (TGFβ) in?vitro. Retinoic acid (RA) enhances induction of CD4(+) Tregs in the presence of TGFβ. We investigated whether RA produced by RPE cells can promote generation of Tregs. We found that in?vitro, RA-treated T cells expressed high levels of Foxp3 in the presence of recombinant TGFβ. In GeneChip analysis, cultured RPE cells constitutively expressed RA-associated molecules such as RA-binding proteins, enzymes, and receptors. RPE from normal mice, but not vitamin A-deficient mice, contained significant levels of TGFβ. RPE-induced Tregs from vitamin A-deficient mice failed to suppress activation of target T cells. Only a few Foxp3(+) T cells were found in intraocular cells from vitamin A-deficient experimental autoimmune uveitis (EAU) mice, whereas expression was higher in cells from normal EAU mice. RA receptor antagonist-pretreated or RA-binding protein-siRNA-transfected RPE cells failed to convert CD4(+) T cells into Tregs. Our data support the hypothesis that RPE cells produce RA, thereby enabling bystander T cells to be converted into Tregs through TGFβ promotion, which can then participate in the establishment of immune tolerance in the eye. 相似文献
996.
Tsuda S Sato T Takahashi F Satoh D Sasaki S Namito Y Iwase H Ban S Takada M 《Journal of radiation research》2012,53(2):264-271
The frequency distributions of the lineal energy, y, of 160 MeV proton, 150 MeV/u helium, and 490 MeV/u silicon ion beams were measured using a wall-less tissue equivalent proportional counter (TEPC) with a site size of 0.72 μm. The measured frequency distributions of y as well as the dose-mean values, y(D), agree with the corresponding data calculated using the microdosimetric function of the particle and heavy ion transport code system PHITS. The values of y(D) increase in the range of LET below ~10 keV μm(-1) because of discrete energy deposition by delta rays, while the relation is reversed above ~10 keV μm(-1) as the amount of energy escaping via delta rays increases. These results indicate that care should be taken with the difference between y(D) and LET when estimating the ionization density that usually relates to relative biological effectiveness (RBE) of energetic heavy ions. 相似文献
997.
998.
999.
Chida K Taniguchi T Maeda S Imai T Esaki Y Takubo K Ohkawa S 《Japanese heart journal》2001,42(2):235-248
The aim of the present retrospective study was to clarify the histopathologic substrates of left ventricular myocardium with transient asynergy due to acute ischemic insult in man. Three patients who had had prolonged chest pain, new abnormal Q waves and new ST segment elevation were studied. There was no significant elevation of serum creatine phosphokinase activity in two of the three patients. Echocardiograms on admission or the next day showed severe hypokinetic or akinetic motion and thinning of the anteroseptal and apical portions of the left ventricle and regional dilatation of the same portions. Disappearance of the abnormal Q waves, ST segment elevation resolution, and early T wave inversion were observed later. Complete improvement of the echocardiographic abnormalities was confirmed after a few weeks in all patients. Manifest ischemic lesions of subendocardial scars of the anteroseptal region of the left ventricle were detected in only one of the three cases by gross examination. However, on microscopic examination, islands of necrotic myocytes were interspersed with islands of viable cells throughout the jeopardized region in one case, although the scattered necrotic foci were restricted to the subendocardium and the trabeculae. Normal myocardium and subendocardial scars were observed in the other two cases. In conclusion, left ventricular myocardium with transient asynergy. detected clinically during acute ischemic attack, consists of normal myocardium or small ischemic lesions primarily in the subendocardium. 相似文献
1000.
Imai Y Poncelet P DeBuyzere M Padfield PL Van Montfrans GA 《Blood pressure monitoring》2000,5(2):137-143
BACKGROUND: Self-measurements of blood pressure may offer some advantage in diagnostic and therapeutic evaluation and in management of patients. However, the most important limitation of self-measurement is that there are limited data available about the prognostic value of this information. RESULTS: Authors of several previous reports demonstrated that self-measurement reflects target-organ damage better than does casual measurement of blood pressure. So far, investigators in Tecumseh and Ohasama studies have provided pilot data on prognostic value of self-measurements. Investigators in Ohasama study demonstrated that self-measurements predict cardiovascular morbidity and mortality and all-cause mortality better than do casual measurements of blood pressure. Investigators in Tecumseh study demonstrated that self-measurement can predict future development of sustained hypertension and of diastolic dysfunction. These preliminary results suggest that self-measurements have strong predictive power for endpoints and surrogate measures of cardiovascular target-organ damage. CONCLUSION: The final answer on the prognostic significance of self-measurement has not been given. Prognostic studies designed to compare casual measurement of blood pressure, self-measurement, and ambulatory blood pressure monitoring are needed. 相似文献