全文获取类型
收费全文 | 67529篇 |
免费 | 5816篇 |
国内免费 | 3666篇 |
专业分类
耳鼻咽喉 | 749篇 |
儿科学 | 879篇 |
妇产科学 | 671篇 |
基础医学 | 8530篇 |
口腔科学 | 1114篇 |
临床医学 | 7554篇 |
内科学 | 11214篇 |
皮肤病学 | 1107篇 |
神经病学 | 4209篇 |
特种医学 | 3214篇 |
外国民族医学 | 19篇 |
外科学 | 7341篇 |
综合类 | 8937篇 |
现状与发展 | 14篇 |
一般理论 | 10篇 |
预防医学 | 4246篇 |
眼科学 | 1688篇 |
药学 | 6791篇 |
51篇 | |
中国医学 | 2990篇 |
肿瘤学 | 5683篇 |
出版年
2024年 | 165篇 |
2023年 | 849篇 |
2022年 | 2174篇 |
2021年 | 3080篇 |
2020年 | 2186篇 |
2019年 | 2090篇 |
2018年 | 2248篇 |
2017年 | 2029篇 |
2016年 | 2235篇 |
2015年 | 3197篇 |
2014年 | 3765篇 |
2013年 | 3856篇 |
2012年 | 5584篇 |
2011年 | 5830篇 |
2010年 | 4073篇 |
2009年 | 3169篇 |
2008年 | 3972篇 |
2007年 | 3874篇 |
2006年 | 3491篇 |
2005年 | 3401篇 |
2004年 | 2559篇 |
2003年 | 2590篇 |
2002年 | 2194篇 |
2001年 | 1544篇 |
2000年 | 1238篇 |
1999年 | 1120篇 |
1998年 | 648篇 |
1997年 | 614篇 |
1996年 | 403篇 |
1995年 | 466篇 |
1994年 | 332篇 |
1993年 | 210篇 |
1992年 | 330篇 |
1991年 | 252篇 |
1990年 | 210篇 |
1989年 | 199篇 |
1988年 | 150篇 |
1987年 | 152篇 |
1986年 | 142篇 |
1985年 | 69篇 |
1984年 | 53篇 |
1983年 | 29篇 |
1982年 | 30篇 |
1981年 | 21篇 |
1980年 | 18篇 |
1979年 | 28篇 |
1977年 | 14篇 |
1974年 | 18篇 |
1973年 | 17篇 |
1969年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
PURPOSETo evaluate the efficacy, safety, and results of direct thrombolytic therapy in intracranial dural sinus thrombosis by infusion of alteplase (recombinant tissue plasminogen activator).METHODSNine patients were treated during a 2-year period for intracranial dural sinus thrombosis. A microcatheter was placed directly into the thrombus in the dural sinus via the transfemoral route. Thrombolysis was initiated with a rapid injection of 10 mg of alteplase over 10 minutes, followed in 3 hours by a continuous infusion of 50 mg, then a continuous infusion at 5 mg per hour until complete thrombolysis or a total dose of 100 mg per day had been reached. Repeat thrombolysis was tried the following day if complete recanalization did not occur at 100 mg per day.RESULTSSuccessful recanalization with improvement of symptoms was achieved in all cases. Time required for complete thrombolysis was between 8 and 43 hours. The total dose of alteplase ranged from 50 to 300 mg. Complications of a small intrapelvic hemorrhage and oozing at a femoral puncture site occurred in separate cases, but were not related to the amount of infused alteplase. MR venograms obtained 1 to 4 weeks after the procedure showed no evidence of reocclusion of the dural sinuses.CONCLUSIONDirect fibrinolytic therapy with alteplase is safe, fast, and effective in treating dural sinus thrombosis. However, to prevent hemorrhagic complications, further studies are required to determine its optimal dose and proper rate of administration. 相似文献
33.
Jin Woo Kim M.D. Ho Shik Kim M.D. In Kyung Kim M.D. Mee Ran Kim M.D. Eun Young Cho B.S. Heung Kee Kim M.D. Joon Mo Lee M.D. Sung Eun Namkoong M.D. 《Gynecologic oncology》1998,69(3):230-236
Transforming growth factor-β1 (TGF-β1) is known to be a potent growth inhibitor for many cell types, including most epithelial cells. In skin keratinocytes, TGF-β1 has been shown to inhibit growth and to rapidly reduce c-mycexpression. However, the molecular mechanism of TGF-β1 action on cell growth of cervical carcinoma has not yet been elucidated. We thus assessed the effect of TGF-β1 on the growth of cervical carcinoma cell lines. Two cervical squamous carcinoma cell lines, CUMC-3 and CUMC-6, were incubated with varying concentrations of TGF-β1, and growth inhibition was evaluated with tetrazolium-based colorimetric assay. After culture in TGF-β1 for 24 h, inhibition of growth was detected in a dose-dependent manner at concentrations of 0.1–10 ng/ml in both cell lines. This effect of TGF-β1 on cultured carcinoma cells was associated with apoptotic process including oligonucleosomal ladder DNA and apoptotic body formations. Northern blot analysis revealed c-mycmRNA expression was suppressed by 10 ng/ml of TGF-β1 following 3 h of treatment in both cell lines. Western blot analysis showed that the level of p27Kip1protein was increased after TGF-β1 treatment in both cell lines. These results suggest that the mechanisms by which TGF-β1 inhibits the growth of cervical carcinoma are complex and may include effects on down-regulation of c-mycgene, and overexpression of p27Kip1protein. 相似文献
34.
原发性小肠恶性肿瘤的CT诊断 总被引:15,自引:0,他引:15
本文回顾性分析34例经病理证实的原发性小肠恶性肿瘤的CT表现。病变包括腺癌16例,平滑肌肉瘤12例,淋巴瘤6例。CT扫描能明确肿瘤向腔内和腔外侵犯的程度,清晰显示肿瘤与邻近结构的关系,有无局部及远处转移等,为临床治疗提供帮助。鉴别诊断应包括小肠良性肿瘤、炎性病变和转移性肿瘤等。 相似文献
35.
B J Dong 《American journal of hospital pharmacy》1990,47(2):356-361
The patient-care activities of a pharmacist in a thyroid clinic are described. Since 1978 a pharmacist has been an active member of the staff of a thyroid clinic associated with a 500-bed university hospital. More than 1500 patients are referred to the clinic each year. The pharmacist initiates, maintains, or modifies the drug therapy of selected patients with physician-diagnosed thyroid disorders under the guidance of written protocols approved by the chief endocrinologist. Most patients treated by the pharmacist are receiving thyroid-suppression therapy, antithyroid drugs for Graves' disease, or thyroid hormone supplementation after surgery or after radioactive iodine therapy. The pharmacist assesses patients, prescribes medications, orders laboratory tests, charts visits and therapeutic plans, and educates patients about their conditions. Major changes in thyroid status and drug therapy are always discussed with the chief endocrinologist. The pharmacist also participates in educational programs to influence prescribing by physicians, provides drug information, serves as a preceptor to pharmacy students, and is investigating the equivalence of levothyroxine preparations in vivo and in vitro. An audit of patient outcomes showed that the pharmacist is highly effective in her role as a giver of direct patient care. A pharmacist's role in a thyroid clinic can consist of clinical practice, education, preceptorship, and research. 相似文献
36.
胃癌D17S261和D17S799位点二核苷酸重复序列不稳定性的意义 总被引:2,自引:2,他引:0
目的研究二核苷酸重复序列不稳定性〔DRSI〕在胃癌发生中的作用及其临床意义.方法采用PCR方法检测了D17S261和D17S799位点二核苷酸重复序列不稳定性.结果胃癌总DRSI发生率为34%(17/50),其中高中分化腺癌DRSI阳性率(667%,10/15)显著高于低分化癌(194%,6/31,P<001);肠型胃癌DRSI阳性率(556%,10/18)显著高于胃型胃癌(20%,6/30,P<005),DRSI与胃癌部位、大小、浸润、分期、淋巴结转移无显著相关.结论DRSI在胃癌的发生中可能起重要作用. 相似文献
37.
Hea-Young P. Choo Hea-Ran Yoon Hwha-Soon Park Dong-Hyun Kim Jongsei Park Dong H. Kim 《Archives of pharmacal research》1998,21(2):168-173
The epoxyalkanoyl derivatives were designed and synthesized as ACE inhibitors. Coupling of unsaturated carboxylic acids with amino acids and following epoxidation with dimethyldioxirane gave the epoxyalkanoyls with high yield. The inhibitory activity of synthesized compounds on angiotensin converting enzyme was IC50 values of 0.06≈5.5 μM. 相似文献
38.
39.
传统腺样体切除术后腺样体残留情况调查 总被引:39,自引:0,他引:39
体统的腺样体手术为腺样体刮除术,为非直视下的手术,虽然多数患者手术后症状得得缓解,但临床上也常常看到手术后短时间内症状复发或者缓解不彻底的患儿,这类情况往往和腺样体手术切除不彻底有关。本院自2003年1月-2004年9月间对腺样体切除术后复发再次手术患者,以鼻内镜观察记录腺样体残留情况,对初次手术患者在进行传统腺样体刮除术并止血后,立即进行鼻内镜检查,了解腺样体残留情况并进行鼻内镜下处理,报告如下。 相似文献
40.
Zhong Rui-kun钟瑞琨 Dong Yong-he董永和and Lu Dao-pei陆道培Institute of Hematology Beijing Medical University Beijing 《中华医学杂志(英文版)》1989,102(7):537-544
In order to understand the mechanism of immunosuppression caused by infusion of placental gamma globulin (PGG) in patients with renal allografts, rheumatoid arthritis, and graft – versus –host disease (GCHD) following bone marrow transplantation (BMT) ,we have examined the effect of PGG in vitro and in a model of the xenogeneic , local graft –ver- sus – host reaction (LGVHR) .PGG inhibited lymphocyte proliferation in mixed lymphocyte cultures (MLC) (P<0.005) and depressed interleukin -2 (IL-2) levels in such cultures at 72 hours (P<0.01) . In contrast phytohemagglutinin (PHA) –and pokeweed mitogen (PWM) –induced T and B lymphocyte blastogenesis was not affected by such PGG treatment .PGG treatment .PGG neither decreased the [3H] TdR pulse incorporation in unstimulated lymphocytes nor affected cell viability .Cell cycle analysis by flow cytometry showed that PGG reduced the percentage of cells in S and G2, M phases during the MLC, but did not alter cell cycling during PWM-stimulated proliferation .
An immunosuppressive effect of PGG on the LGCHR was tested in a model of intracutaneous transplantation of PGG –treat human lymphocytes into cyclophosphamide – immunosuppressed rats. Lymphoprep – separated human tonsillar lymphocytes were incubated with RPMI-1640 buffer containing:(1)PGG,4mg/ml,(2) human plasma albumin,4mg/ml,(3)mitomycin-C,25ug/ml, or (4) no additive. Cell of each preparation (3x107cells in 0.1ml) were injected intracutaneously into cyclophosphamide-treated male rats at separate abdominal locations. A fifth site received only the buffer solution. Five days after injection of cells ,each rat received [125 I]IUdR (10uCi) intraperitoneally and was killed after 5 hours. For each site of injection, the diameters of induration were measured and 125 I was counted . There was no difference between buffer – treated and a ibumin – treated groups either in the diameter of the area of induration (t=0.66;P>0.5)or in radioactive counts(t=0.22;P>0.05).In the PGG –treated group, the induration and radioactivity measurements were significantly less than in control groups (t=3.72 and P<0.1;t=2.62 and P<0.02,respectively ) Cytophilic antibodies in PGG were thought to inhibit an early phase of T cell activation, and not to be cytotoxicity .In the LGVHR, the immune response might be abrogated either by immuno- regulatory suppression of T cell function or by toxicity to the infused lymphoid cells. For some clinical purposes, immuno- modulating, human antibodies might be preferred to murine, monoclonal antibodies. 相似文献