全文获取类型
收费全文 | 189315篇 |
免费 | 33051篇 |
国内免费 | 2579篇 |
专业分类
耳鼻咽喉 | 5462篇 |
儿科学 | 6062篇 |
妇产科学 | 2997篇 |
基础医学 | 8063篇 |
口腔科学 | 2482篇 |
临床医学 | 29237篇 |
内科学 | 56885篇 |
皮肤病学 | 8095篇 |
神经病学 | 17430篇 |
特种医学 | 7682篇 |
外科学 | 48067篇 |
综合类 | 413篇 |
现状与发展 | 72篇 |
预防医学 | 8230篇 |
眼科学 | 3766篇 |
药学 | 3804篇 |
中国医学 | 141篇 |
肿瘤学 | 16057篇 |
出版年
2024年 | 701篇 |
2023年 | 4998篇 |
2022年 | 1624篇 |
2021年 | 3850篇 |
2020年 | 6440篇 |
2019年 | 2719篇 |
2018年 | 8092篇 |
2017年 | 7886篇 |
2016年 | 9009篇 |
2015年 | 9106篇 |
2014年 | 16366篇 |
2013年 | 16636篇 |
2012年 | 7126篇 |
2011年 | 7229篇 |
2010年 | 11290篇 |
2009年 | 14976篇 |
2008年 | 7309篇 |
2007年 | 5616篇 |
2006年 | 8061篇 |
2005年 | 5414篇 |
2004年 | 4726篇 |
2003年 | 3592篇 |
2002年 | 3682篇 |
2001年 | 5421篇 |
2000年 | 4594篇 |
1999年 | 4723篇 |
1998年 | 4156篇 |
1997年 | 3879篇 |
1996年 | 3725篇 |
1995年 | 3529篇 |
1994年 | 2258篇 |
1993年 | 1844篇 |
1992年 | 2353篇 |
1991年 | 2325篇 |
1990年 | 1851篇 |
1989年 | 2064篇 |
1988年 | 1778篇 |
1987年 | 1541篇 |
1986年 | 1618篇 |
1985年 | 1386篇 |
1984年 | 975篇 |
1983年 | 893篇 |
1982年 | 703篇 |
1981年 | 586篇 |
1980年 | 492篇 |
1979年 | 614篇 |
1978年 | 567篇 |
1977年 | 606篇 |
1975年 | 485篇 |
1972年 | 459篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
941.
942.
943.
Masaki Shinoda Tsuyoshi Yamaguchi Yoshimi Tanaka Osamu Sato Sin Kobayashi Yutaka Suzuki 《Child's nervous system》1992,8(4):219-221
Single photon emission computerized tomography (SPECT) is now widely used as one of the tools in evaluating cerebral blood flow (CBF). The authors report the CBF changes in childhood hydrocephalus. Five pediatric cases studied by 123I-IM SPECT in children are presented. The authors counted radioactivities both in early and delayed images in each patient, and calculated the reabsorption ratio (RR). Two negative-RR cases and three positive-RR cases were found. All of the negative-RR patients had a poor prognosis, while all of the positive-RR patients had a favorable outcome. 相似文献
944.
Yoshimitsu Kuroyanagi DR. ENG DR. SCI DR. MED ; Akihiko Shiraishi MD ; Yoshiteru Shirasaki MD ; Nobuaki Nakakita MD ; Yoshiaki Yasutomi MD ; Yasuo Takano MD ; Nobuyuki Shioya MD FACS 《Wound repair and regeneration》1994,2(2):122-129
A bilaminar wound dressing composed of an outer membrane and an inner three-dimensional matrix of a fabric or a sponge may be considered to constitute an ideal structure that promotes wound healing: the outer membrane prevents body fluid loss, controls water evaporation, and protects the wound surface from bacterial invasion, and the inner matrix encourages adherence by tissue growth into the matrix. Using this concept, we developed a biosynthetic wound dressing with a drug delivery capability. This medicated wound dressing is composed of a spongy sheet of a chitosane derivative and collagen mixture that is laminated to an antimicrobial-impregnated polyurethane membrane. In this study, a gentamycin sulfate-impregnated wound dressing was prepared and evaluated. The antimicrobial efficacy of this wound dressing was examined on an agar plate seeded with Pseudomonas aeruginosa. Also, the cytotoxicity of an antimicrobial released from this wound dressing was examined in an in vitro system with cultured skin substitutes. Both in vitro tests have shown that this wound dressing is capable of suppressing bacterial growth and minimizing cellular damage. In addition, in the treatment of wounds inflicted on rats and rabbits, this wound dressing was shown to be efficacious in covering full-thickness and split-thickness skin defects. Finally, the efficacy of this wound dressing was evaluated in a nonrandomized open-label study of 31 clinical cases. In 31 cases treated with this wound dressing, good or excellent wound healing was achieved. 相似文献
945.
946.
T Tsuji T Yamamuro Y Kotoura M Matsumoto H Tanaka C Tanaka J Toguchida K Endo H Sakahara M Koizumi 《Nuclear medicine communications》1988,9(12):947-954
Bone scintigraphy was performed in 17 patients with previously known lung metastases of osteosarcoma. 99Tcm-MDP uptake was observed in all primary bone lesions but lung metastatic lesions were positive in only six patients (35%). 99Tcm-MDP uptake by lung metastases was significantly correlated with bone and osteoid formation in the metastatic lesions and preoperative serum ALPase values. These clinical observations were confirmed by using nude mice transplanted with human lung metastatic osteosarcoma. 99Tcm-MDP scintigraphy appears to be useful for detecting lung metastases of osteosarcoma only in a selected group of patients. 相似文献
947.
948.
H Tanaka 《Nihon Geka Gakkai zasshi》1987,88(4):469-477
In order to study the changes of lipid metabolism in acute pancreatitis, the following experiments were performed in monogrel dogs. Bile-induced pancreatitis (severe type) and collagenase-induced pancreatitis (mild type) were prepared, and changes of FFA, TG, IRI and IRG were determined for one week. In addition, IVFTT and PHLA were determined at 24th hour, on the 3rd day and 7th day. A rise of FFA was observed during the first 24 hours, which was considered the lypolytic stage. On the 3rd day TG reached the maximal level, while K values in IVFTT and PHLA showed the lowest levels. The above results suggest that the elimination mechanism of TG was impaired on the 3rd day. Changes of FFA, TG, IRI and IRG showed marked differences between the two groups. Therefore it is thought that lipid metabolism in acute pancreatitis is regulated by balance of endogenous pancreatic hormones. 相似文献
949.
Julia E. Ledger MSc Graham J. Watson Dr. Juliet E. Compston MD 《Digestive diseases and sciences》1986,31(4):361-368
The biliary excretion of radioactivity after intravenous [3H]25-hydroxyvitamin D3 was studied in nine patients with T-tube bile drainage. The mean +/- SD 24-hr radioactivity excretion in T-tube bile expressed as a percentage of the administered dose was 6.7 +/- 2.9%; after correction for incomplete bile collection, the value obtained was 16.0 +/- 11.1%. Chloroform solubility of biliary radioactivity increased from 27.4 +/- 8.9% to 72.9 +/- 10.1% following incubation with beta-glucuronidase. High-performance liquid chromatographic analysis of chloroform extracts of bile revealed that most of the eluted radioactivity was more polar than [3H]25-hydroxyvitamin D3. No free [3H]25-hydroxyvitamin D3 was demonstrated. Thus in man, most of the biliary radioactivity excreted following [3H]25-hydroxyvitamin D3 is in the form of water-soluble compounds, mainly glucuronides. However, our results suggest that glucuronides of metabolites other than 25-OHD3 are predominantly formed. 相似文献
950.