全文获取类型
收费全文 | 5092篇 |
免费 | 218篇 |
国内免费 | 43篇 |
专业分类
耳鼻咽喉 | 27篇 |
儿科学 | 82篇 |
妇产科学 | 49篇 |
基础医学 | 625篇 |
口腔科学 | 104篇 |
临床医学 | 322篇 |
内科学 | 1270篇 |
皮肤病学 | 40篇 |
神经病学 | 478篇 |
特种医学 | 183篇 |
外科学 | 1009篇 |
综合类 | 26篇 |
一般理论 | 4篇 |
预防医学 | 230篇 |
眼科学 | 84篇 |
药学 | 318篇 |
中国医学 | 11篇 |
肿瘤学 | 491篇 |
出版年
2023年 | 36篇 |
2022年 | 72篇 |
2021年 | 121篇 |
2020年 | 43篇 |
2019年 | 71篇 |
2018年 | 98篇 |
2017年 | 74篇 |
2016年 | 92篇 |
2015年 | 101篇 |
2014年 | 118篇 |
2013年 | 144篇 |
2012年 | 232篇 |
2011年 | 242篇 |
2010年 | 145篇 |
2009年 | 133篇 |
2008年 | 220篇 |
2007年 | 238篇 |
2006年 | 249篇 |
2005年 | 223篇 |
2004年 | 213篇 |
2003年 | 233篇 |
2002年 | 242篇 |
2001年 | 199篇 |
2000年 | 180篇 |
1999年 | 160篇 |
1998年 | 68篇 |
1997年 | 49篇 |
1996年 | 50篇 |
1995年 | 36篇 |
1994年 | 35篇 |
1993年 | 45篇 |
1992年 | 104篇 |
1991年 | 115篇 |
1990年 | 82篇 |
1989年 | 114篇 |
1988年 | 83篇 |
1987年 | 88篇 |
1986年 | 58篇 |
1985年 | 55篇 |
1984年 | 45篇 |
1983年 | 48篇 |
1981年 | 26篇 |
1979年 | 32篇 |
1978年 | 27篇 |
1977年 | 22篇 |
1976年 | 24篇 |
1973年 | 30篇 |
1972年 | 29篇 |
1971年 | 29篇 |
1969年 | 21篇 |
排序方式: 共有5353条查询结果,搜索用时 15 毫秒
41.
42.
43.
Fukui K Kominami R Kaneuji A Matsumoto T Shinohara H 《Okajimas folia anatomica Japonica》2004,81(4):57-62
We report a new method of perfusion fixation for the proximal one-third of the femur of the Japanese white rabbit. Fluids to flush the blood and fix the marrow were injected into the abdominal aorta and drained from the stump of the femur. The oozing of the fluids from the stumps guaranteed complete flushing and fixation. The new method facilitated fixation and decreased the volume of necessary fluids. Scanning electron microscopy (SEM) images of bone marrow fixed using the new method and using the conventional method did not differ. Large fat globules were not observed in the SEM specimens produced using either the new or the conventional method. 相似文献
44.
Dr M. Kimura T. Sugiura Y. Fukui T. Kimura Y. Harada 《Medical & biological engineering & computing》1992,30(2):155-161
Two ways of rate control for diaphragm pacing are proposed. One is rate control using only the patients' body temperature
(method I). The other is rate control by both the patients' heart rate and body temperature (method II). To test the effectiveness
of these methods, a diaphragm pacemaker which can be controlled by both heart rate and body temperature has been developed.
It was applied to nine mongrel dogs. The pacing rate is controlled by atrial blood temperature (method I) or by both heart
rate and temperature (method II). The animal's metabolism was elevated by the administration of a pyrogenic drug. It was found
that method I is not suited to rapid changes in metabolism; however, it is useful in extreme metabolic elevation. An animal's
metabolism was supported by using method II in all ranges of metabolism. This method proved more effective than method I for
rate-responsive diaphragm pacing. 相似文献
45.
Association of Actinobacillus actinomycetemcomitans leukotoxin with nucleic acids on the bacterial cell surface. 总被引:2,自引:1,他引:2 下载免费PDF全文
Actinobacillus actinomycetemcomitans, a periodontopathic gram-negative bacterium, produces a leukotoxin that is a member of the RTX cytotoxin family. Although genes may function in toxin secretion, the leukotoxin is not secreted extracellularly but remains associated with the bacterial cell surface. We report here that this toxin-cell surface association is mediated by nucleic acids and directly demonstrate that the extracellular secretion of toxin occurs in growing cultures with increased ionic strength of medium. All examinations were performed with freshly harvested A. actinomycetemcomitans 301-b from anaerobic fructose-limited chemostat cultures. The occurrence of cell surface-localized DNA was shown by directly digesting whole cells with the restriction endonuclease EcoRI or HindIII, which yielded many DNA fragments. The cell surface DNA constituted about 20% of the total cellular DNA. The leukotoxin was released from the whole cells by digestion with DNase I as well as restriction endonucleases. Because the leukotoxin binds ionically to DNA, it is dependent on the ionic strength of buffers or media. Accordingly, the toxin was released from cells suspended in saline at pH 7.5 in the presence of increasing amounts of MgCl2 (0 to 10 mM) or NaCl (0 to 50 mM). Moreover, a considerable quantity of leukotoxin was detected in the culture supernatant of fructose-limited chemostat cultures when sodium succinate solution was pumped into the steady state as an additional salt (30 and then 50 mM). This toxin-DNA association was also found in well-characterized strains including not only the leukotoxin-producing ATCC 29522 but also the toxin production-variable ATCC 29523 and the non-leukotoxin-producing ATCC 33384 when these strains were grown in the chemostat culture. 相似文献
46.
47.
Comparison of an immunochromatography test with multiplex reverse transcription-PCR for rapid diagnosis of respiratory syncytial virus infections 下载免费PDF全文
Kuroiwa Y Nagai K Okita L Ukae S Mori T Hotsubo T Tsutsumi H 《Journal of clinical microbiology》2004,42(10):4812-4814
A new commercial rapid 10-min one-step immunochromatography (IC) test, SAS RSV test, was compared to another IC test, Directigen EZ RSV, employing RT-PCR as the "gold standard" for detecting respiratory syncytial virus. Of 102 clinical samples, 79 were positive by RT-PCR, 66 (82.5%) were positive with the SAS RSV test, and 55 (69.6%) were positive with Directigen EZ RSV. The specificity of the new test was 91.3% (21 of 23), similar to that of Directigen EZ RSV (100% [23 of 23]). This test performs well enough to be used for patient care. 相似文献
48.
Hashimoto I Murakami G Nakanishi H Sakata-Haga H Seike T Sato TJ Fukui Y 《Okajimas folia anatomica Japonica》2001,78(1):23-30
We investigated the cutaneous blood supply in the gluteal and perineal regions of 35 donated cadavers to provide an anatomical basis for reliable vulvo-vaginal reconstruction using a skin flap such as the so-called gluteal fold flap. The cutaneous areas along the gluteal cleft and sulcus were likely to be supplied by 3 routes: 1) the internal pudendal artery (IPA), especially its first cutaneous branch; 2) perforators running through the gluteus maximus muscle and arising from the inferior gluteal artery (IGA); and 3) a non-perforator running around and inferior to the ischial tuberosity and originating from the IGA. Route 1 supplied the skin along the gluteal cleft, route 2 the gluteal fold (i.e., a bulky skin fold along the upper edge of the gluteal sulcus), and route 3, just along the gluteal sulcus. In those 3 routes, we noted the consistent morphology of the thick and long, first cutaneous branch of the IPA. The first arterial branch, 1.5 mm in diameter at its origin on average (ranging from 0.7-2.6 mm), usually originated from the IPA under the cover of or at the inferomedial or distal side of the sacrotuberous ligament (almost always less than 20 mm from the inferomedial margin of the ligament). The branch ran superomedially toward the coccyx or ran medially in the ischiorectal fat. It accompanied the vein and nerve at its distal (peripheral) course although the nerve often ran independently at its proxomal course near the ligament. Therefore, the first branch of the IPA seems to provide a reliable pedicle using the skin along the gluteal cleft whether the incision for approach is conducted along the gluteal sulcus or not. However, if the gluteus maximus muscle extended much inferomedially, the pedicle would be very short. In this case, preparation of the pedicle seems to be necessary along the arterial course under the cover of the muscle. 相似文献
49.
50.
Inhibitory effect of estradiol-17 beta and progesterone on bactericidal activity in uteri of rabbits infected with Escherichia coli. 下载免费PDF全文
The influence of ovarian hormones at different estrous stages on the bactericidal activity of the uterus in rabbits was investigated. When Escherichia coli cells were inoculated in ligated uteri, the survival period of the bacteria in the uterus at the luteal phase was clearly longer than that at the follicular phase. At the luteal phase, high levels of plasma estradiol-17 beta and progesterone were detected. A luteolytic treatment with prostaglandin F2 alpha and human chorionic gonadotropin at the luteal phase lowered plasma progesterone levels and prompted bacterial clearance from the uterus. In ovariectomized rabbits, E. coli from the uterine exudates was not detected 6 days after the inoculation in both the nontreated and estradiol-17 beta-treated animals. In the progesterone-treated rabbits, the survival period of E. coli was longer than that in the nontreated and estradiol-17 beta-treated animals. When estradiol-17 beta and progesterone at the ratio of 1:100 were administered concurrently, E. coli survived for the longest period in the rabbits treated with various doses of different hormones. Formalin-killed E. coli cells were inoculated into the uterine lumen, and 4 h later the proportion of heterophils phagocytizing the bacteria dropped in the progesterone-treated rabbits and in the estradiol-17 beta- and progesterone-treated rabbits, but there was no significant difference in heterophil numbers among the rabbits treated with different hormones. The present results suggest that progesterone inhibits the bactericidal activity of the uterus and that estrogen concurrently secreted at the luteal phase promotes the inhibitory action of progesterone, although estrogen alone hardly affects the uterine defense. In addition, the lowering of the bactericidal activity of the uterus at the luteal phase may be attributable to lower activity of phagocytosis by heterophils infiltrated into the uterine lumen. 相似文献