全文获取类型
收费全文 | 61410篇 |
免费 | 5326篇 |
国内免费 | 4064篇 |
专业分类
耳鼻咽喉 | 522篇 |
儿科学 | 804篇 |
妇产科学 | 1067篇 |
基础医学 | 7834篇 |
口腔科学 | 969篇 |
临床医学 | 7820篇 |
内科学 | 9608篇 |
皮肤病学 | 705篇 |
神经病学 | 3629篇 |
特种医学 | 2309篇 |
外国民族医学 | 53篇 |
外科学 | 6270篇 |
综合类 | 8273篇 |
现状与发展 | 20篇 |
一般理论 | 3篇 |
预防医学 | 4131篇 |
眼科学 | 1670篇 |
药学 | 6420篇 |
62篇 | |
中国医学 | 3053篇 |
肿瘤学 | 5578篇 |
出版年
2024年 | 178篇 |
2023年 | 940篇 |
2022年 | 2398篇 |
2021年 | 3139篇 |
2020年 | 2285篇 |
2019年 | 2136篇 |
2018年 | 2256篇 |
2017年 | 1893篇 |
2016年 | 1899篇 |
2015年 | 2713篇 |
2014年 | 3372篇 |
2013年 | 2838篇 |
2012年 | 4476篇 |
2011年 | 4948篇 |
2010年 | 2993篇 |
2009年 | 2297篇 |
2008年 | 3171篇 |
2007年 | 3194篇 |
2006年 | 3193篇 |
2005年 | 3161篇 |
2004年 | 2160篇 |
2003年 | 2093篇 |
2002年 | 1816篇 |
2001年 | 1276篇 |
2000年 | 1343篇 |
1999年 | 1435篇 |
1998年 | 940篇 |
1997年 | 898篇 |
1996年 | 686篇 |
1995年 | 628篇 |
1994年 | 517篇 |
1993年 | 333篇 |
1992年 | 424篇 |
1991年 | 373篇 |
1990年 | 331篇 |
1989年 | 286篇 |
1988年 | 295篇 |
1987年 | 241篇 |
1986年 | 234篇 |
1985年 | 184篇 |
1984年 | 127篇 |
1983年 | 98篇 |
1982年 | 54篇 |
1981年 | 52篇 |
1980年 | 40篇 |
1979年 | 97篇 |
1978年 | 41篇 |
1975年 | 40篇 |
1974年 | 52篇 |
1973年 | 30篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
B. B. Y. Ma A. Oza E. Eisenhauer† G. Stanimir‡ M. Carey§ W. Chapman¶ E. Latta¶ K. Sidhu J. Powers† W. Walsh† A. Fyles 《International journal of gynecological cancer》2004,14(4):650-658
A multicenter phase II trial was conducted to define the activity of letrozole in postmenopausal women with recurrent or advanced endometrial carcinoma, who had no more than one prior line of progestins and never had chemotherapy (except adjuvant). Archival paraffin-embedded tumor samples were retrieved to determine the expression level of estrogen (ER) and progesterone receptor (PgR), p53, HER-2, bcl-2 and PTEN protein, and phosphorylation status of protein kinase B (PKB/Akt). Thirty-two eligible patients were treated with letrozole at 2.5 mg daily continuously, of whom 10 (31%) had prior progestins. Of the 28 patients evaluated for response, one complete and two partial responses were noted; overall response was 9.4% (95% confidence interval 2-25%). Eleven patients had stable disease for a median duration of 6.7 months (range 3.7-19.3 months). Amongst 22 patients who had tumor blocks available, the proportion showing positive expression of the following markers includes: PgR (86%), ER (86%), PTEN (82%), phosphorylated PKB/Akt (59%), bcl-2 (45%), p53 (32%), and HER-2 (0%). None of these markers correlated with response to letrozole or disease progression. In conclusion, letrozole is well tolerated but has little overall activity in this cohort of women with endometrial cancer. 相似文献
112.
目的:探讨适合睫状体缝合复位术病人的护理方法。方法:对34例(34只眼)因外伤致睫状体分离和脱离导致低眼压,随后行睫状体缝合复位术的病人进行观察和护理。结果:32只眼术后1周至6个月眼压恢复正常,其中5只眼术后2~5个月内分别进行第二次手术或氩离子激光光凝而痊愈。视力改善者21例,无变化者13例。结论:睫状体缝合复位术是治疗外伤性睫状体分离和脱离的有效方法。术前行超声生物显微镜(UBM)检查、术后密切观察眼压变化并给予正确处理、做好心理护理和出院指导是确保手术成功的重要措施。 相似文献
113.
Previous findings from this laboratory with the intracerebral microinjection technique suggested that the periaqueductal gray (PAG), nucleus accumbens, and habenula might constitute a unidirectional loop to play their roles in pain modulation. In the present study we demonstrate that intra-habenular injection of naloxone antagonizes the analgesia elicited by morphine injected into the periaqueductal gray (PAG) and that intra-accumbens injection of naloxone is capable of attenuating the analgesic effects of morphine injected into the habenula. These results indicate that the relationships between these nuclei may be more complex than the putative unidirectional loop. 相似文献
114.
1988~1991年对内蒙古锡盟地区389例蒙古族新生儿进行了活体观察测量,取得了22项总体发育指标及相应的各项性别指标的均值数据,并以其中体重、身长、顶臀长(坐高)、头围、胸围及上臂围等6项指标与国内外有关资料作了比较和性别间的对比分析,从结果来看,体重高于本地区平均水平110g,高于国内某些城市140~202g;身长及坐高分别矮于本地区平均水平5.13cm及6.54cm,分别矮于国内某些城市4.88~4.89cm及6.60cm。呈圆头型、手足宽短、身躯宽短的粗壮体型。 相似文献
115.
116.
117.
N S Ma 《中华整形烧伤外科杂志》1992,8(2):127-9, 165-6
The portal circulation was reduced to 50% for one hour by partially occluding the superior mesenteric artery, and the relationship between the changes in malondialdehyde (MDA) and multiple organ damage was studied. The results showed that there was a marked change in hepatic enzymology, with MDA values significantly elevated in serum and lung and liver tissues after the reperfusion when compared with controls. These results suggested that lipid peroxidation initiated by free oxygen radicals played an important role in the multiple organ damages, and the extent of organ damage was closely correlated with the contents of MDA in tissues. 相似文献
118.
Hemorrhagic shock-induced bacterial translocation is reduced by xanthine oxidase inhibition or inactivation 总被引:11,自引:0,他引:11
E A Deitch W Bridges J Baker J W Ma L Ma M B Grisham D N Granger R D Specian R Berg 《Surgery》1988,104(2):191-198
Experiments were performed to determine whether bacterial translocation (BT) after hemorrhagic shock is due to a reperfusion injury mediated by xanthine oxidase-derived oxidants. Rats were subjected to 30 minutes of shock (30 mm Hg) followed by reinfusion of shed blood. Twenty-four hours after hemorrhage and reinfusion, the mesenteric lymph node, liver, and spleen were harvested from each animal for bacterial culture, and the ileum and cecum were examined histologically. Sham-shocked (control) rats were instrumented, but blood was not withdrawn. The incidence of BT was higher in the shocked rats (61%) than in the sham-shocked animals (7%) (p less than 0.01). Allopurinol (50 mg/kg, administered orally), a competitive inhibitor of xanthine oxidase, reduced the incidence of shock-induced BT to 14% (p = 0.02). Similarly, rats fed a tungsten-supplemented molybdenum-free diet, which inactivates xanthine oxidase, reduced shock-induced BT to 10% (p = 0.02). The histologic damage cause by hemorrhagic shock was prevented by blocking xanthine oxidase activity. Thus hemorrhagic shock-induced bacterial translocation from the gut appears to be mediated by oxidants generated by activation of the xanthine oxidase system. 相似文献
119.
Manifestation of EGF receptors and enhancement of an anticancer agent by EGF were studied in cultured cells derived from female genital cancers. 1) The numbers of EGF-receptors of SKG-3a, RMUG-s, HUOA, A-431 and HEC-1 were 1.22 x 10(4), 6.94 x 10(4), 2.75 x 10(4), 5.25 x 10(5) and 0.92 x 10(4) sites per cell respectively. The values for the dissociation constant (Kd) of RMUG-s, SKG-3a, HUOA and HEC-1 were 340pM, 477pM, 989pM and 2,187pM, respectively. 2) All cell lines were stimulated by EGF at low concentrations and inhibited at higher concentrations. The growth stimulation rates for SKG-3a, HEC-1, HUOA and RMUG-s in the presence of 0.01 nM EGF at 48 hours were 8, 18, 21.1 and 3.7%, respectively. The growth inhibition rates for SKG-3a, A-431, HEC-1, HUOA and RMUG-s in the presence of 1.0 nM EGF at 48 hours were 32, 28, 25.8, 11.2 and 6.8%, respectively. 3) The antitumor effect of CDDP was enhanced by the presence of EGF at both a concentration of 0.01 nM (except for A-431) and a concentration of 1.0 nM, in all cell lines. 4) EGF receptors of RMUG-s and HUOA were decreased by CDDP. The values for RMUG-s and HUOA were 1.71 x 10(4), 0.52 x 10(4) (CDDP 0.4 microgram/ml) and 0.95 x 10(4), 0.29 x 10(4) sites per cell (CDDP 2.0 micrograms/ml), respectively. The effect of CDDP on EGF receptors was not recognized in SKG-3a and HEC-1. In brief, EGF receptors were significantly expressed in cell lines derived from female genital cancers.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
120.