全文获取类型
收费全文 | 6403篇 |
免费 | 383篇 |
国内免费 | 33篇 |
专业分类
耳鼻咽喉 | 46篇 |
儿科学 | 132篇 |
妇产科学 | 115篇 |
基础医学 | 816篇 |
口腔科学 | 296篇 |
临床医学 | 430篇 |
内科学 | 1728篇 |
皮肤病学 | 138篇 |
神经病学 | 504篇 |
特种医学 | 216篇 |
外科学 | 957篇 |
综合类 | 24篇 |
预防医学 | 208篇 |
眼科学 | 78篇 |
药学 | 451篇 |
中国医学 | 6篇 |
肿瘤学 | 674篇 |
出版年
2023年 | 42篇 |
2022年 | 83篇 |
2021年 | 112篇 |
2020年 | 68篇 |
2019年 | 99篇 |
2018年 | 122篇 |
2017年 | 106篇 |
2016年 | 132篇 |
2015年 | 139篇 |
2014年 | 200篇 |
2013年 | 208篇 |
2012年 | 345篇 |
2011年 | 409篇 |
2010年 | 207篇 |
2009年 | 182篇 |
2008年 | 341篇 |
2007年 | 330篇 |
2006年 | 293篇 |
2005年 | 308篇 |
2004年 | 277篇 |
2003年 | 322篇 |
2002年 | 302篇 |
2001年 | 165篇 |
2000年 | 177篇 |
1999年 | 201篇 |
1998年 | 90篇 |
1997年 | 64篇 |
1996年 | 57篇 |
1995年 | 55篇 |
1994年 | 38篇 |
1993年 | 33篇 |
1992年 | 121篇 |
1991年 | 105篇 |
1990年 | 113篇 |
1989年 | 112篇 |
1988年 | 100篇 |
1987年 | 89篇 |
1986年 | 98篇 |
1985年 | 83篇 |
1984年 | 72篇 |
1983年 | 64篇 |
1982年 | 29篇 |
1981年 | 21篇 |
1980年 | 29篇 |
1979年 | 35篇 |
1978年 | 33篇 |
1977年 | 28篇 |
1971年 | 26篇 |
1970年 | 19篇 |
1969年 | 21篇 |
排序方式: 共有6819条查询结果,搜索用时 15 毫秒
41.
Ishitobi M Haginoya K Zhao Y Ohnuma A Minato J Yanagisawa T Tanabu M Kikuchi M Iinuma K 《Neuroreport》2000,11(18):4033-4035
The progression of muscular weakness of patients suffering from muscular dystrophies directly correlates with the progressive loss of myofibers, accompanied by fibrosis. Since transforming growth factor beta1 (TGF-beta1) promotes tissue fibrosis, we measured the plasma TGF-beta1 level in patients with various muscular dystrophies in order to determine whether the level is elevated in patients with muscular dystrophy and if the level reflects the severity of tissue fibrosis. The plasma TGF-beta1 level was significantly elevated in patients with Duchenne muscular dystrophy and congenital muscular dystrophy (CMD), but not in those with Becker muscular dystrophy. Growth factors related to muscle fiber regeneration and fibrosis might be a key factor in the progression of muscular dystrophy and could be a target for therapeutic studies. 相似文献
42.
Nakamura Y Aso E Yashiro M Uehara R Watanabe M Tajimi M Oki I Ojima T Yanagawa H Kawasaki T 《Acta paediatrica (Oslo, Norway : 1992)》2005,94(4):429-434
Aim: To clarify the question of whether patients with Kawasaki disease suffer a higher mortality rate after the incidence of the disease in comparison with age-matched healthy individuals. Methods: Between July 1982 and December 1992, 52 collaborating hospitals collected data on all patients having a new, definite diagnosis of Kawasaki disease. Patients were followed up until 31 December 2001 or their death. The expected number of deaths was calculated from Japanese vital statistics data and compared with the observed number. Results: Of 6576 patients enrolled, 29 (20 males and 9 females) died. The standardized mortality ratio (SMR: the observed number of deaths divided by the expected number of deaths based on the vital statistics in Japan) was 1.15 (95% CI: 0.77-1.66). In spite of the high SMRs during the acute phase, the mortality rate was not high after the acute phase for the entire group of patients. Although the SMR after the acute phase was 0.75 for those without cardiac sequelae, six males (but none of the females) with cardiac sequelae died during this period; and the SMR for the male group with cardiac sequelae was 1.95 (95% CI: 0.71-4.25). The mortality from congenital anomalies of the circulatory system was elevated, but no increase in cancer deaths was observed.
Conclusion: Although it was not statistically significant, the mortality rate among males with cardiac sequelae due to Kawasaki disease appeared to be higher than in the general population. On the other hand, the mortality rates for females with the sequelae and both males and females without sequelae were not elevated. 相似文献
Conclusion: Although it was not statistically significant, the mortality rate among males with cardiac sequelae due to Kawasaki disease appeared to be higher than in the general population. On the other hand, the mortality rates for females with the sequelae and both males and females without sequelae were not elevated. 相似文献
43.
Morimatsu Y Matsubara S Hirose N Ohkuchi A Izumi A Ozaki K Ozawa K Suzuki M 《Archives of gynecology and obstetrics》2008,277(3):267-270
Background Disseminated intravascular coagulation (DIC) caused by placental abruption usually improves rapidly after prompt delivery
and adequate anti-DIC treatment.
Case A 30-year-old nulliparous woman suffered from placental abruption at the 25th week of pregnancy, and emergent cesarean section
was done immediately. She exhibited DIC, which continued even after termination of the pregnancy and anti-DIC treatment. She
also showed neutropenia. We closely observed her, and at the 58th day postpartum, blast cells appeared in the peripheral blood
and she was diagnosed with acute promyelocytic leukemia (APL). Induction chemotherapy was done successfully. The close observation
after delivery enabled us to make the prompt diagnosis/treatment, leading to the complete remission.
Conclusion APL should be added to the list of differential diagnosis when DIC persists even after prompt delivery and appropriate anti-DIC
treatment after placental abruption. 相似文献
44.
Matsubara S Izumi A Nagai T Kikkawa I Suzuki M 《Archives of gynecology and obstetrics》2008,278(2):195-197
BACKGROUND: While vaginal breech delivery, although rare, can cause femur fracture, abdominal breech delivery is not expected to cause it. CASE: A 2,490-g female infant was delivered at term by elective cesarean section for breech presentation. She sustained a fracture of the femur shaft. A simple splinting led to a complete healing of the fracture without sequelae. CONCLUSION: Although abdominal breech delivery reduces the risk of birth trauma, we must be aware that femur fracture can occur regardless of the mode of delivery. 相似文献
45.
Kusuoka H Yamasaki Y Izumi T Kashiwagi A Kawamori R Shimamoto K Yamada N Nishimura T 《Annals of nuclear medicine》2008,22(1):13-21
Objective Diabetes mellitus is an independent risk factor for acute myocardial infarction. Thus, a surveillance study was conducted
as part of studies to create a national database related to electrocardiogram (ECG)-gated myocardial perfusion single-photon
emission computed tomography (SPECT) of ischemic heart disease.
Methods Single-photon emission computed tomography was conducted in patients with type 2 diabetes mellitus and their prognoses will
be followed for 3 years, stratified by patients’ clinical background and SPECT findings.
Results A total of 513 patients from 50 institutions were enrolled in this study, 297 of whom were men (age 66.2 ± 0.4 years, mean
± SEM) and 261 women (age 67.8 ± 0.5 years). They have a history of retinopathy (25.3%), neuropathy (19.9%), cerebrovascular
disorder, chronic obstructive pulmonary disease, and photocoagulation. Major risk factors for present disease were hypertension
(82.3%) and hyperlipidemia (79.7%). In 244 patients (129 men and 115 women), body mass index (BMI) was 25 or more. Fifty-two
of them (10.1%) underwent coronary angiography; of these, 26 (50.0%) had no coronary artery lesions with 75% or more stenosis,
and only 1 (1.9%) had a left main trunk with 50% or more stenosis. An overwhelming majority of patients (94.3%) underwent
SPECT imaging by a 1-day stress-followed-by-rest procedure. Stress procedure was exercise in most (70.8%) patients, followed
by dipyridamole infusion in 14.6%, adenosine infusion in 6.6%, and adenosine triphosphate infusion in 5.7%. Endpoint of stress
examination was most often fatigue in lower limbs (40.7%), followed by completion of pharmacological stress protocol (28.7%),
and achievement of target heart rate (26.3%). The largest number of patients (198, 38.6%) received 99mTc-tetrofosmin at an initial dosage of 200–300 MBq (mean 331 ± 3 MBq) followed by a second dosage of 700–800 MBq (mean 748
± 8 MBq). Among them, 491 (95.7%) received some kind of therapeutic drug: hypoglycemic drugs were used by the largest number
(83.2%), followed by hypotensive (66.7%), hypolipidemic (40.7%), and antiplatelet drugs (27.7%), vasodilators (5.5%), and
antioxidants and others (2.3%).
Conclusions This study was designed to clarify the correlation between coronary artery disease and diabetes mellitus as its risk factor
based on the clinical and imaging findings. Patient enrollment was closed on September 30, 2005, and follow-up is now under
way. 相似文献
46.
Minami A Iseki M Kishi K Wang M Ogura M Furukawa N Hayashi S Yamada M Obata T Takeshita Y Nakaya Y Bando Y Izumi K Moodie SA Kajiura F Matsumoto M Takatsu K Takaki S Ebina Y 《Diabetes》2003,52(11):2657-2665
A tyrosine kinase adaptor protein containing pleckstrin homology and SH2 domains (APS) is rapidly and strongly tyrosine phosphorylated by insulin receptor kinase upon insulin stimulation. The function of APS in insulin signaling has heretofore remained unknown. APS-deficient (APS(-/-)) mice were used to investigate its function in vivo. The blood glucose-lowering effect of insulin, as assessed by the intraperitoneal insulin tolerance test, was increased in APS(-/-) mice. Plasma insulin levels during fasting and in the intraperitoneal glucose tolerance test were lower in APS(-/-) mice. APS(-/-) mice showed an increase in the whole-body glucose infusion rate as assessed by the hyperinsulinemic-euglycemic clamp test. These findings indicated that APS(-/-) mice exhibited increased sensitivity to insulin. However, overexpression of wild-type or dominant-negative APS in 3T3L1 adipocytes did not affect insulin receptor numbers, phosphorylations of insulin receptor, insulin receptor substrate-1, or Akt and mitogen-activated protein kinase. The glucose uptake and GLUT4 translocation were not affected by insulin stimulation in these cells. Nevertheless, the insulin-stimulated glucose transport in isolated adipocytes of APS(-/-) mice was increased over that of APS(+/+) mice. APS(-/-) mice also showed increased serum levels of leptin and adiponectin, which might explain the increased insulin sensitivity of adipocytes. 相似文献
47.
Shintaro Sukegawa Rieko Shimizu Yuka Sukegawa Kazuaki Hasegawa Sawako Ono Ai Fujimura Izumi Yamamoto Keisuke Nakano Kiyofumi Takabatake Hotaka Kawai Hitoshi Nagatsuka Yoshihiko Furuki 《Materials》2022,15(9)
This retrospective study clarified the success rate of endoscopic endodontic surgeries and identified predictors accounting for successful surgeries. In this retrospective study, 242 patients (90 males, 152 females) who underwent endoscopic endodontic surgery at a single general hospital and were diagnosed through follow-up one year later were included. Risk factors were categorized into attributes, general health, anatomy, and surgery. Then, the correlation coefficient was calculated for the success or failure of endodontic surgery for each variable, the odds ratio was calculated for the upper variable, and factors related to the surgical prognosis factor were identified. The success rate of endodontic surgery was 95.3%, showing that it was a highly predictable treatment. The top three correlation coefficients were post, age, and perilesional sclerotic signs. Among them, the presence of posts was the highest, compared with the odds ratio, which was 9.592. This retrospective study revealed the success rate and risk factors accounting for endoscopic endodontic surgeries. Among the selected clinical variables, the presence of posts was the most decisive risk factor determining the success of endodontic surgeries. 相似文献
48.
Matsuoka A Minato M Harada M Kubo H Bandou Y Tangoku A Nakano K Nishitani H 《Radiation Medicine》2008,26(1):15-20
Purpose The aim of this study was to compare diffusion-weighted imaging (DWI) at 3.0 T and 1.5 T by evaluating the apparent diffusion
coefficient (ADC) value and visibility of breast cancer in the same patients.
Materials and methods A total of 13 patients (16 lesions) with breast cancer underwent DWI at 3.0 T and 1.5 T. Tumors were classified into two groups
based on the lesion size. The ADC values were measured, and visibility of the tumors was scored blindly.
Results No significant difference was found for ADC values between 3.0 T and 1.5 T in either group (P > 0.05). All of the large lesions were visible clearly at both magnetic field strengths, and image scores were not different
(P > 0.05). In contrast, small lesions were more clearly visible and had better image scores at 3.0 T than at 1.5 T (P < 0.001).
Conclusion Small cancers were more clearly visible on DWI at 3.0 T than 1.5 T. 相似文献
49.
Shimono T Tsuboyama T Kuwabara M Im SW Yagyu Y Imaoka I Ashikaga R Hosono M Murakami T 《Radiation Medicine》2008,26(3):151-155
Purpose Motion artifact is problematic in the diagnosis of Creutzfeldt-Jakob disease (CJD) because of dementia. The purpose was to
compare the occurrence of this artifact between a diffusion-weighted (DW) magnetic resonance (MR) imaging sequence and conventional
sequences.
Materials and methods Ten MR examinations comprising T2-weighted, T1-weighted, DW, and fluid-attenuated inversion recovery imaging in seven CJD
patients were retrospectively evaluated. The occurrence of motion artifacts on each sequence were assessed, and the examination
was classified into four groups as follows: group A, motion artifact not revealed on DW imaging but revealed on one or more
other sequences; group B, revealed on DW imaging and one or more other sequences; group C, not revealed on any sequences;
and group D, revealed on DW imaging but not on any other sequences.
Results The 10 MR examinations were classified as eight group A (80%), one B (10%), one C (10%), and zero D (0%).
Conclusion Motion artifacts are likely to occur in any conventional imaging sequences in CJD, but the fast-imaging ability of DW imaging
can reduce this artifact. The combination of an absence of motion artifact on DW imaging and the presence on conventional
sequences may be one of the frequent findings of CJD. 相似文献
50.
OBJECTIVE: This study examined the effects of varying magnitudes of controlled spinal cord impact to the mouse spinal cord on neurological and histopathological variables to obtain a mouse model of spinal cord injury (SCI). METHODS: A laminectomy of the T10 vertebra was performed on anesthetized C57BL/6 mice. A pneumatic pressure-driven impact was performed on the spinal cord through the dura mater. Experimental groups were subdivided according to the energy of impact (0.25-mm-deep deformations): Group 1 (n = 5), impact velocity at 1 m/s; Group 2 (n = 5), impact velocity at 2 m/s; and Group 3 (n = 5), impact velocity at 3 m/s. Functional deficits over time were evaluated up to 28 days after SCI by testing hindlimb reflex and coordinated motor function. The extent of the lesions was analyzed histopathologically and quantified by a morphometric measurement. RESULTS: Mice of all groups exhibited profound functional deficits immediately after injury and subsequent gradual symptomatic recovery. The degrees of recovery were precisely correlated with the magnitudes of impact. The extent of resultant cord lesions was highly reproducible among animals, with little variance: means +/- standard deviation, 0.86 +/- 0.06/100 mm3 in Group 1; 2.4 +/- 0.28/100 mm3 in Group 2; and 11.0 +/- 1.0/100 mm3 in Group 3. CONCLUSION: Our results indicate that this model provides constant functional and histopathological lesions according to impact energy. This new mouse model of SCI opens a new avenue for studies investigating roles and/or effects of specific genes in the recovery process of SCI. 相似文献