全文获取类型
收费全文 | 5032篇 |
免费 | 185篇 |
国内免费 | 16篇 |
专业分类
耳鼻咽喉 | 24篇 |
儿科学 | 105篇 |
妇产科学 | 29篇 |
基础医学 | 836篇 |
口腔科学 | 143篇 |
临床医学 | 286篇 |
内科学 | 1362篇 |
皮肤病学 | 56篇 |
神经病学 | 514篇 |
特种医学 | 241篇 |
外科学 | 646篇 |
综合类 | 9篇 |
预防医学 | 130篇 |
眼科学 | 66篇 |
药学 | 361篇 |
中国医学 | 14篇 |
肿瘤学 | 411篇 |
出版年
2023年 | 14篇 |
2022年 | 39篇 |
2021年 | 61篇 |
2020年 | 28篇 |
2019年 | 45篇 |
2018年 | 67篇 |
2017年 | 59篇 |
2016年 | 64篇 |
2015年 | 74篇 |
2014年 | 70篇 |
2013年 | 110篇 |
2012年 | 216篇 |
2011年 | 268篇 |
2010年 | 169篇 |
2009年 | 148篇 |
2008年 | 247篇 |
2007年 | 278篇 |
2006年 | 289篇 |
2005年 | 288篇 |
2004年 | 345篇 |
2003年 | 367篇 |
2002年 | 386篇 |
2001年 | 120篇 |
2000年 | 124篇 |
1999年 | 126篇 |
1998年 | 75篇 |
1997年 | 80篇 |
1996年 | 74篇 |
1995年 | 52篇 |
1994年 | 41篇 |
1993年 | 50篇 |
1992年 | 80篇 |
1991年 | 69篇 |
1990年 | 67篇 |
1989年 | 60篇 |
1988年 | 45篇 |
1987年 | 60篇 |
1986年 | 40篇 |
1985年 | 54篇 |
1984年 | 58篇 |
1983年 | 34篇 |
1982年 | 32篇 |
1981年 | 36篇 |
1980年 | 32篇 |
1979年 | 28篇 |
1978年 | 16篇 |
1977年 | 19篇 |
1975年 | 15篇 |
1974年 | 14篇 |
1972年 | 16篇 |
排序方式: 共有5233条查询结果,搜索用时 265 毫秒
1.
Kayoko Minakata Masako Suzuki Hideki Nozawa Kunio Gonmori Kanako Watanabe Osamu Suzuki 《Forensic Toxicology》2006,24(2):83-87
Platinum (Pt) levels were determined in various tissues and body fluids obtained from a patient who died 181 days after cisplatin
overdosing. The symptoms of cisplatin overdose, however, might have almost disappeared by day 40, and the patient’s death
was ascribed to the recurrence of malignant lymphoma. Determination of Pt derived from cisplatin was performed by electrospray
ionization mass spectrometry (ESI-MS) using silver (Ag) as internal standard. Pt and Ag complexed with diethyldithiocarbamate
(DDC) in wetashed blood, and tissue solutions were extracted into isoamyl alcohol, and then acidified with oxalic acid. By
injecting an aliquot of the isoamyl alcohol layer into a mass spectrometer in the direct flow injection mode, the quantitation
was performed using the signals of Pt(DDC)3
+ and Ag(DDC)2
+ at m/z 639 and 403, respectively. The Pt levels ranged from 25ng/ml in blood to 2050ng/g wet weight in the liver of the patient,
indicating that Pt remained at high levels in tissues, even after a period as long as 181 days after cisplatin overdosing. 相似文献
2.
Takako Miyamae Masaaki Mori Yasuji Inamo Youichi Kohno Shuji Takei Motoharu Maeda Takuji Murata Shuji Nakata Hiroshi Kawai Yukiko Hirano Yukiji Date Katsuhiko Kitamura Shumpei Yokota 《Ryūmachi》2003,43(3):538-543
OBJECTIVES: To reveal the frequency and the clinical characteristics of dystrophic calcification that occurs in children with juvenile dermatomyositis, multi-center analysis was constructed. METHOD: Fifty children with JDM were enrolled, and 14 of them (28.0%) were complicated with calcinosis. Clinical symptoms and laboratory tests at onset, initial therapy and disease course were compared in children with and without calcinosis. RESULTS: The mean age of the onset of calcinosis was 4.78 +/- 3.33 years, and it was younger than those of children without calcinosis (8.66 +/- 3.85 years) (P = 0.0017). No differences of clinical manifestation except Gower's sign were observed. The frequency of positive anti-nuclear antibody was 7.1% in children with calcinosis and 52.9% without calcinosis (P = 0.0112). The initial therapy of methylprednisolon pulses gave no effects on prognosis of calcium deposition. The calcinosis appeared in 1.56 +/- 1.91 year after the onset of the disease. The various types of calcium deposition including large tumorous clumps, subcutaneous plaques or nodules, sheet-type calcification were deserved. They appeared over knee joints (64.3%), elbow joint (64.3%), and hip processes (50.0%). Calcinosis affecting the subcutaneous tissues frequently resulted in painful superficial ulceration of the overlying skin (42.9%), local infection (50.0%), and limitation of joint movement (14.3%). Although aluminum phosphate was effective in 2 children among 7, no other effective treatment was recommended. In 5 cases, surgical removal of tumorous clumps was operated. Thus, juvenile dermatomyositis is frequently complicated with calcinosis. This type of calcinosis was found to be unlikely to resolve completely, and resulted in severe disability in children. 相似文献
3.
Yongkang Nie Qiang Li Feng Li Yonglin Pu Daniel Appelbaum Kunio Doi 《Journal of nuclear medicine》2006,47(7):1075-1080
Our objective was to develop and evaluate 3 semiautomatic computer-aided diagnostic (CAD) schemes for distinguishing between benign and malignant pulmonary nodules by use of features extracted from CT, 18F-FDG PET, and both CT and 18F-FDG PET. METHODS: We retrospectively collected 92 consecutive cases of pulmonary nodules (<3 cm) in patients who underwent both thoracic CT and whole-body PET/CT. Forty-two of the nodules were malignant and 50 benign, as confirmed by pathologic examination and clinical follow-up. The interval between CT and PET was less than 1 mo. Four clinical parameters, including patient age, sex, smoking status, and history of previous malignancy, were used for the CAD schemes. Sixteen CT features based on size, shape, margin, and internal structure of nodules were independently rated subjectively by 2 chest radiologists. Four PET features were viewed on a PET/CT workstation. CAD schemes based on clinical parameters together with CT features, PET features, and both CT and PET features were then used to differentiate benign from malignant nodules. Finally, the output from the CAD schemes was evaluated by use of receiver-operating-characteristic analysis. RESULTS: When we used clinical parameters and CT features as input units (CAD scheme 1), the area under the receiver-operating-characteristic curve (A(z) value) of the CAD scheme was 0.83. When we used clinical parameters and PET features as input units (CAD scheme 2), the A(z) value for the computer output was 0.91. However, when we used all data as input units (CAD scheme 3), the A(z) value for the computer output was 0.95. The performance of CAD scheme 3 was better than that of CAD scheme 1 or 2. A statistically significant difference existed between the A(z) values of CAD schemes 3 and 2 (P = 0.037) and between those of CAD schemes 3 and 1 (P = 0.015). CONCLUSION: Our CAD scheme based on both PET and CT was better able to differentiate benign from malignant pulmonary nodules than were the CAD schemes based on PET alone and CT alone. 相似文献
4.
Hiroki Otani Yutaka Kagaya Yoshio Imahori Satoshi Yasuda Ryo Fujii Masanobu Chida Shigeto Namiuchi Morihiko Takeda Masahito Sakuma Jun Watanabe Tatsuo Ido Hiroshi Nonogi Kunio Shirato 《Journal of nuclear medicine》2005,46(4):553-559
Left ventricular (LV) remodeling after myocardial infarction (MI) is a maladaptive process that increases the risk of heart failure and death. The myocardial phosphoinositide cycle, which is located downstream from several neurohumoral factors, plays a crucial role in LV remodeling. Our animal studies demonstrated that 1-[1-11C]butyryl-2-palmitoyl-rac-glycerol (11C-DAG) can be used to visualize regions with an activated phosphoinositide cycle. Therefore, we examined whether myocardial 11C-DAG accumulation assessed by PET is relevant to LV enlargement and systolic dysfunction in post-MI patients. METHODS: We performed PET with 11C-DAG in 13 post-anteroseptal MI patients and 4 healthy volunteers. We placed regions of interest on the noninfarcted myocardium and calculated the myocardium-to-left atrial (LA) chamber ratio of 11C-DAG accumulation. RESULTS: The myocardium-to-LA chamber ratio of 11C-DAG was significantly higher in the post-MI patients (mean +/- SD, 1.73 +/- 0.35) compared with that of the healthy volunteers (mean +/- SD, 1.25 +/- 0.13; P < 0.05). In the post-MI patients, the myocardium-to-LA chamber ratio of (11)C-DAG was significantly correlated with the LV end-diastolic volume index (r = 0.79, P < 0.01) and the plasma concentration of brain natriuretic peptide (r = 0.85, P < 0.001) and negatively correlated with the LV ejection fraction (r = -0.69, P < 0.01). CONCLUSION: These findings suggest that the myocardial 11C-DAG accumulation assessed by PET is relevant to LV enlargement, LV systolic dysfunction, and humoral activation in post-MI patients. This new imaging strategy based on intracellular signaling may contribute to the assessment and treatment of post-MI patients. 相似文献
5.
6.
The effect of the hepatic energy status on the development of posttraumatic jaundice (PTJ) was studied to clarify the mechanism of PTJ. Fifty-four patients with severe torso injury who were expected to develop PTJ on admission with an average Injury Severity Score of 27 were selected for this study. They were retrospectively divided into three groups according to their maximum bilirubin concentration by day 10: group H, 12 patients with marked elevation of serum bilirubin (>8 g/dl); group L, 23 with mild bilirubinemia (2–8 g/dl); and group N, 19 with no bilirubinemia (<2 g/dl). Group H patients, in whom trauma-related shock was severe and prolonged, developed severe hyperbilirubinemia, and their arterial ketone body ratio (AKBR), which reflects the hepatic mitochondrial redox state and is closely correlated to its energy production, was significantly lower throughout the first week. In contrast, the AKBR increased to an above normal level, indicating enhanced energy production in groups N and L. The serum direct/total bilirubin was also higher in group H. The abnormal hepatic energy metabolism is considered to have reduced the excretion of conjugated bilirubin from the hepatocytes into the bile canaliculi, which is a process that has to proceed against the bilirubin concentration gradient. The subsequent diffusion of the accumulated water-soluble conjugated bilirubin in hepatocytes into the blood is thus considered to be one of the causes of PTJ. 相似文献
7.
Gliomatosis cerebri with good prognosis 总被引:4,自引:0,他引:4
Seiji Kannuki Hideki Hondo Kunio Ii Takanori Hirose Keizo Matsumoto 《Brain tumor pathology》1997,14(1):53-57
A 52-year-old man was admitted to our clinic with severe headache and bilateral papilledema. Magnetic resonance (MR) images
on admission demonstrated diffuse swelling of the cerebral cortex without formation of a tumor mass. Biopsy revealed diffuse
infiltration with neoplastic glial cells. After radiation and chemotherapy, the MR images returned to normal. The morphological
and neurological features of the present case met the criteria for gliomatosis cerebri. However, this patient showed an unusually
good response to radiation and chemotherapy. 相似文献
8.
Immunohistochemical detection of imidazolone, a novel advanced glycation end product, in kidneys and aortas of diabetic patients. 总被引:11,自引:0,他引:11 下载免费PDF全文
T Niwa T Katsuzaki S Miyazaki T Miyazaki Y Ishizaki F Hayase N Tatemichi Y Takei 《The Journal of clinical investigation》1997,99(6):1272-1280
To investigate the role of the Maillard reaction in the pathogenesis of diabetic complications, we produced several clones of monoclonal antibodies against advanced glycation end products (AGEs) by immunizing mice with AGE-modified keyhole limpet hemocyanin, and found that one clone (AG-1) of the anti-AGE antibodies reacted specifically with imidazolones A and B, novel AGEs. Thus, the imidazolones, which are the reaction products of the guanidino group of arginine with 3-deoxyglucosone (3-DG), a reactive intermediate of the Maillard reaction, were found to be common epitopes of AGE-modified proteins produced in vitro. We determined the erythrocyte levels of imidazolone in diabetic patients using ELISA with the monoclonal anti-imidazolone antibody. The imidazolone levels in the erythrocytes of diabetic patients were found to be significantly increased as compared with those of healthy subjects. Then we studied the localization of imidazolone in the kidneys and aortas obtained from diabetic patients by immunohistochemistry using the antibody. Specific imidazolone immunoreactivity was detected in nodular lesions and expanded mesangial matrix of glomeruli, and renal arteries in an advanced stage of diabetic nephropathy, as well as in atherosclerotic lesions of aortas. This study first demonstrates the localization of imidazolone in the characteristic lesions of diabetic nephropathy and atherosclerosis. These results, taken together with a recent demonstration of increased serum 3-DG levels in diabetes, strongly suggest that imidazolone produced by 3-DG may contribute to the progression of long-term diabetic complications such as nephropathy and atherosclerosis. 相似文献
9.
Increase in survival time of liver transplants by protease inhibitors and a calcium channel blocker, nisoldipine 总被引:2,自引:0,他引:2
Kupffer cells are activated by calcium and release a variety of toxic mediators, including proteases. The purpose of these studies, therefore, was to determine if protease inhibitors and a calcium channel blocker could increase survival time in the rat model of orthotopic liver transplantation. Survival for 30 days was greater than 90% in this model when livers were stored for 1 hr in Ringer's solution (survival conditions)--however, grafts stored for 4 hr in Euro-Collins solution or 8 hr in University of Wisconsin (UW) solution survived postoperatively only 1.2 and 0.7 days, respectively (nonsurvival conditions). When livers were stored for 4 hr in Euro-Collins containing a cocktail of protease inhibitors (leupeptin, pepstatin A, phenylmethylsulfonyl fluoride, 20 ng/ml each; diisopropyl fluorophosphate, 100 microM) and subsequently transplanted, however, survival time was increased significantly to 11.5 days. Inclusion of a calcium channel blocker, nisoldipine (1.4 microM), in the protease inhibitor cocktail increased survival time to 23 days. Actually, nisoldipine alone increased survival time to 25 days. Nisoldipine alone also increased survival time in livers stored for 8 or 16 hr in UW solution to between 15 and 20 days. Serum transaminase levels reached peak values greater than 2400 U/L one day postoperatively in the nonsurvival groups, and liver injury assessed histologically was apparent. Under these conditions, pulmonary infiltration of inflammatory cells was observed in about 60% of the lungs examined and was associated with massive bleeding. Inclusion of the protease cocktail, nisoldipine, or both in the storage solutions decreased maximal SGOT levels and injury to both liver and lung significantly by about 50% postoperatively. Nisoldipine also decreased phagocytosis of carbon particles by the perfused liver 2- to 3-fold following storage under nonsurvival conditions (half-maximal effect = 0.3-0.4 microM nisoldipine). Moreover, nisoldipine improved hepatic microcirculation. It accelerated blood flow into the liver, as indexed by hemoglobin reflectance from the liver surface. These data support the hypothesis that Kupffer cells are activated early in the sequence of events that causes graft failure leading to endothelial cell-mediated alterations in the microcirculation. This work demonstrates clearly that dihydropyridine-type calcium channel blockers such as nisoldipine may be clinically useful in storage solutions for liver prior to transplantation. 相似文献
10.