全文获取类型
收费全文 | 1554篇 |
免费 | 97篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 38篇 |
妇产科学 | 28篇 |
基础医学 | 201篇 |
口腔科学 | 34篇 |
临床医学 | 114篇 |
内科学 | 339篇 |
皮肤病学 | 119篇 |
神经病学 | 94篇 |
特种医学 | 86篇 |
外科学 | 133篇 |
综合类 | 16篇 |
预防医学 | 93篇 |
眼科学 | 23篇 |
药学 | 73篇 |
中国医学 | 2篇 |
肿瘤学 | 253篇 |
出版年
2023年 | 19篇 |
2022年 | 50篇 |
2021年 | 74篇 |
2020年 | 39篇 |
2019年 | 48篇 |
2018年 | 62篇 |
2017年 | 41篇 |
2016年 | 49篇 |
2015年 | 42篇 |
2014年 | 68篇 |
2013年 | 68篇 |
2012年 | 109篇 |
2011年 | 113篇 |
2010年 | 49篇 |
2009年 | 38篇 |
2008年 | 89篇 |
2007年 | 92篇 |
2006年 | 81篇 |
2005年 | 57篇 |
2004年 | 54篇 |
2003年 | 44篇 |
2002年 | 31篇 |
2001年 | 26篇 |
2000年 | 32篇 |
1999年 | 32篇 |
1998年 | 8篇 |
1997年 | 4篇 |
1996年 | 10篇 |
1995年 | 6篇 |
1994年 | 7篇 |
1993年 | 6篇 |
1992年 | 21篇 |
1991年 | 15篇 |
1990年 | 23篇 |
1989年 | 25篇 |
1988年 | 24篇 |
1987年 | 9篇 |
1986年 | 8篇 |
1985年 | 14篇 |
1984年 | 12篇 |
1983年 | 5篇 |
1981年 | 3篇 |
1979年 | 5篇 |
1978年 | 3篇 |
1975年 | 7篇 |
1974年 | 3篇 |
1971年 | 3篇 |
1970年 | 4篇 |
1969年 | 6篇 |
1967年 | 6篇 |
排序方式: 共有1657条查询结果,搜索用时 15 毫秒
101.
The Value of Ultrasound-Guided Fine-Needle Aspiration Cytology for Thyroid Nodules: An Assessment of Its Diagnostic Potential and Pitfalls 总被引:2,自引:0,他引:2
Ogawa Y Kato Y Ikeda K Aya M Ogisawa K Kitani K Onoda N Ishikawa T Haba T Wakasa K Hirakawa K 《Surgery today》2001,31(2):97-101
This study was conducted to assess the diagnostic potential and pitfalls of performing fine-needle aspiration cytology (FNAC)
for thyroid nodules. We retrospectively analyzed 1012 aspirated samples obtained from 806 thyroid nodules by the ultrasound
(US)-guided method. Of these 806 nodules, 226 (31%) had been surgically treated, 152 (67%) of which were histologically diagnosed
as malignant. The rate of sufficient aspirate was 82%, being lower in nodules with a diameter of less than 5 mm (73%, P = 0.10); either calcified (77%, P = 0.043) or benign (72%, P = 0.0002). The accuracy of FNAC was 75%, the rate of indeterminate diagnosis was 16%, the false negative rate was 13%, and
the positive malignancy rate was 99%. The rate of indeterminate diagnosis was higher in adenomatous goiter, follicular carcinoma,
and malignant lymphoma, at P = 0.015, P = 0.0008, and P = 0.035, respectively. The accuracy was lower in follicular carcinoma and malignant lymphoma (both at P = 0.013). Sufficient aspirate was finally obtained from 701 (87%) of the 806 nodules by repeated aspiration. Of 152 malignant
nodules, 28 (18%) were diagnosed after two or more aspirations, and the accuracy was improved to 81% by repeating the procedure.
These findings indicated that repeated aspiration may be a simple and effective method of improving the diagnostic potential
of FNAC.
Received: November 1, 1999 / Accepted: September 26, 2000 相似文献
102.
Functional assessment of canine kidneys after acute vascular occlusion on Gd-DTPA-enhanced dynamic echo-planar MR imaging 总被引:2,自引:0,他引:2
RATIONALE AND OBJECTIVES: To assess the alteration in renal transit of gadolinium diethylenetriaminepentaacetic acid (Gd-DTPA) in dog kidneys after acute vascular occlusion on dynamic echo-planar imaging (EPI). METHODS: Dynamic 240-ms EPI series (repetition time/echo time/inversion time [TR/TE/TI] = 3000/42.1/100 ms) of the midcoronal plane of both kidneys of dogs anesthetized by intravenous administration of phenobarbital sodium and ketamine hydrochloride were obtained before and after ligation of the left renal vein (n = 6) or artery (n = 6) for 40 minutes after a 2-second-rate bolus injection of a 0.05 mmol/kg dose of Gd-DTPA. Renal Gd-DTPA transit was analyzed on the time-DeltaR2* curves in each layer of the outer cortex (OC), juxtamedullary cortex and outer zone of the medulla (JMC-OM), and the inner zone of the medulla (IM). The results were compared with those in six normal animals and those of a fast gradient-echo T1-weighted dynamic study performed in other vein- (n = 6) or artery- (n = 6) occluded animals and six normal animals. The histopathological basis of the altered Gd-DTPA transit was also evaluated. RESULTS: The dynamic EPI showed rapid Gd-DTPA transit through each of the five concentric layers, with three separate peaks on the time-DeltaR2* curves. The vein-occluded kidneys showed immediate swelling, with a significant increase in the cross-sectional area proportion of the JMC-OM layer compared with normals (32% +/- 2% vs 24% +/- 2%, P < 0.0001) and intensely congested capillaries, tubular, obliterated material, and gradual and persistent enhancement of the OC and JMC-OM layers but poor Gd-DTPA migration to the IM layer. The artery-occluded kidneys showed a significant reduction in the entire cross-sectional area compared with normals (1352 +/- 69 vs 1432 +/- 47 mm(2), P < 0.05) and poor enhancement, with significant decreases in the area under the time-DeltaR2* curve of the OC and JMC-OM layers compared with the vein-occluded kidneys (79 +/- 50 vs 324 +/- 108 and 82 +/- 42 vs 326 +/- 113, respectively; both P < 0.0001), despite minimal histological damage. In both models, the nonaffected kidneys showed significant increases in the area under the time-DeltaR2* curves compared with baseline. The time course of vascular and tubular Gd-DTPA transit was more detailed by the EPI study than by the T1-weighted imaging study. CONCLUSIONS: Echo-planar imaging has an excellent ability to follow the rapid, renal Gd-DTPA transit through the regional anatomy of the canine kidney. After venous occlusion, the JMC-OM layer may be the most affected site, primarily causing renal swelling and interruption of tubular Gd-DTPA transit and concentration. In contrast, an initial block of vascular Gd-DTPA inflow is the primary effect of arterial occlusion. Nonaffected kidneys seem to compensate by increasing excretion of Gd-DTPA. 相似文献
103.
S Horiike S Misawa H Kaneko Y Sasai M Kobayashi H Fujii S Tanaka M Yagita T Abe K Kashima M Taniwaki 《Leukemia》1999,13(8):1235-1242
We examined chromosomes and molecular aberrations in 21 patients with therapy-related leukemias (t-AML) or myelodysplastic syndromes (t-MDS). All patients showed abnormal karyotypes, and chromosomal losses of No. 5 and/or No. 7 (-5/5q- and/or -7/7q-) were identified in 12 patients. Among these 12, six patients (50%) harbored a TP53 mutation, and two of five examined showed microsatellite instability, suggesting replication error (RER+) phenotype. Meanwhile, among the other nine patients without -5/5q- and/or -7/7q-, none harbored a TP53 mutation, and none of five examined showed RER+ phenotype. Thus, TP53 mutations and RER+ phenotype were preferentially associated with specific chromosomal losses in t-AML/MDS. We then screened for mutational events in representative DNA mismatch repair genes; exons 5-7 and 12-15 of the hMSH2 gene and exon 9 of hMLH1. Notably, two unrelated patients showing RER+ phenotype had an identical missense alteration at codon 419 of hMSH2 in their marrow cells and fibroblasts, which were not found in 120 DNA samples from healthy volunteers or patients with other hematological disorders. Consequently, this study revealed a possible relationship of RER+ phenotype accompanying an hMSH2 alteration to the development of therapy-related AML/MDS in association with TP53 mutations and specific chromosomal losses, and suggests that some patients may be predisposed to myelodysplasia after chemotherapy for their primary tumor. 相似文献
104.
105.
106.
M Fushiki K Ono K Sasai Y Shibamoto K Tsutsui T Nishidai M Takahashi M Abe 《International journal of radiation oncology, biology, physics》1990,18(2):353-357
We report the effect of human granulocyte colony-stimulating factor (hG-CSF) on the recovery from granulocytopenia induced by irradiation. Female 9-week old C3H/He mice were used. The irradiation schedule was as follows: Group 1 and 2 received whole-body irradiation of 1 Gy and 5 Gy, respectively, on day 0; Group 3 and 4 received whole-body irradiation of 0.5 and 1.0 Gy, respectively, for 5 consecutive days; Group 5 received upper hemibody irradiation of 3 Gy for 5 consecutive days. Daily subcutaneous injections of G-CSF (3 x 10(5) Unit/mouse) or 0.3 ml of saline to each group were started from the day after the first irradiation and continued for 18 days. Mice were sampled randomly from each group, and the total number of leukocytes, erythrocytes of peripheral blood, nucleated cells in femur, and spleen weight were counted and measured, respectively, on day 0, 3, 5, 7, 9, 12, and 18. The leukocyte counts decreased with an increase in radiation doses. In Group 1 and 2 mice, G-CSF enhanced the leukocyte count more than saline. In Group 3 mice, the recovery of leukocytopenia was facilitated by G-CSF, but in Group 4 mice, G-CSF had no effect on the leukocyte count decrease or on leukocytopenia recovery. In Group 5 mice, G-CSF greatly affected leukocytopenia recovery. Increase in spleen weight paralleled the peripheral leukocyte count. Daily administration of recombinant hG-CSF accelerated the granulocytopenia recovery which was induced by irradiation, and it may be a useful therapeutic agent for treating myelosuppressive cases. 相似文献
107.
Iseoka Hiroko Sasai Masao Miyagawa Shigeru Takekita Kazuhiro Date Satoshi Ayame Hirohito Nishida Azusa Sanami Sho Hayakawa Takao Sawa Yoshiki 《Journal of artificial organs》2022,25(1):50-58
Journal of Artificial Organs - A major concern in the clinical application of cell therapy is the manufacturing cost of cell products, which mainly depends on quality control. The mycoplasma test,... 相似文献
108.
Go Noguchi Mitsuko Furuya Yoichiro Okubo Yoji Nagashima Ikuma Kato Kana Matsumoto Reiko Tanaka Shin‐ichi Hisasue Masahiro Yao Takeshi Kishida 《International journal of urology》2018,25(9):832-835
Hereditary leiomyomatosis and renal cell cancer is a rare genetic disorder characterized by cutaneous and uterine leiomyomatosis, and an aggressive type 2 papillary renal cell carcinoma. The disease is caused by a germline mutation in the fumarate hydratase gene. We report a familial hereditary leiomyomatosis and renal cell cancer in two siblings. A 34‐year‐old woman underwent nephrectomy for treatment of a renal cell carcinoma. The patient's sister had been diagnosed with renal cell carcinoma at 28 years‐of‐age and died of the disease. Neither sister had apparent skin tumors. Histopathology of the renal cell carcinomas of the siblings showed tubulocystic and papillary architectures with high nuclear grades. Immunostaining showed no fumarate hydratase expression in either tumor. Genomic DNA sequencing of the patient showed a germline mutation in the fumarate hydratase gene (c.675delT). Although there is no epidemiological information on Asian hereditary leiomyomatosis and renal cell cancer, physicians should be aware that typical cutaneous leiomyomatosis might not always be present in patients with hereditary leiomyomatosis and renal cell cancer. 相似文献
109.
Bednarz Haley M. Stavrinos Despina Svancara Austin M. Sherrod Gabriela M. McManus Benjamin Deshpande Hrishikesh D. Kana Rajesh K. 《Brain topography》2022,35(2):251-267
Brain Topography - Drivers with neurodevelopmental disorders (NDDs), such as autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are at increased risk of experiencing... 相似文献
110.
Urinary chondroitin of epidermolysis bullosa cystrophica et albo-papuloidea (Pasini) 总被引:1,自引:0,他引:1
M Endo R Yamamoto Z Yosizawa Y Sasai N Saito 《Clinica chimica acta; international journal of clinical chemistry》1974,57(3):249-253
The major urinary glycosaminoglycan and its related substance were separated from a patient suffering from epidermolysis bullosa dystrophica et albo-papuloidea (Pasini), and characterized as partially degraded chondroitin B and chondroitin sulfate B, respectively. Moreover, the amounts of partially degraded chondroitin sulfates C and/or A, the major glycosaminoglycans in normal urine, decreased in this disease. 相似文献