全文获取类型
收费全文 | 8153篇 |
免费 | 505篇 |
国内免费 | 126篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 44篇 |
妇产科学 | 1660篇 |
基础医学 | 1555篇 |
口腔科学 | 4篇 |
临床医学 | 477篇 |
内科学 | 275篇 |
皮肤病学 | 119篇 |
神经病学 | 55篇 |
特种医学 | 73篇 |
外国民族医学 | 1篇 |
外科学 | 1777篇 |
综合类 | 1182篇 |
一般理论 | 6篇 |
预防医学 | 584篇 |
眼科学 | 6篇 |
药学 | 349篇 |
3篇 | |
中国医学 | 526篇 |
肿瘤学 | 86篇 |
出版年
2024年 | 20篇 |
2023年 | 81篇 |
2022年 | 138篇 |
2021年 | 284篇 |
2020年 | 322篇 |
2019年 | 252篇 |
2018年 | 211篇 |
2017年 | 271篇 |
2016年 | 245篇 |
2015年 | 231篇 |
2014年 | 468篇 |
2013年 | 561篇 |
2012年 | 442篇 |
2011年 | 417篇 |
2010年 | 400篇 |
2009年 | 378篇 |
2008年 | 375篇 |
2007年 | 379篇 |
2006年 | 414篇 |
2005年 | 326篇 |
2004年 | 296篇 |
2003年 | 310篇 |
2002年 | 265篇 |
2001年 | 172篇 |
2000年 | 165篇 |
1999年 | 164篇 |
1998年 | 110篇 |
1997年 | 103篇 |
1996年 | 125篇 |
1995年 | 124篇 |
1994年 | 92篇 |
1993年 | 79篇 |
1992年 | 67篇 |
1991年 | 68篇 |
1990年 | 48篇 |
1989年 | 59篇 |
1988年 | 62篇 |
1987年 | 35篇 |
1986年 | 22篇 |
1985年 | 35篇 |
1984年 | 28篇 |
1983年 | 24篇 |
1982年 | 18篇 |
1981年 | 23篇 |
1980年 | 30篇 |
1979年 | 18篇 |
1978年 | 11篇 |
1977年 | 4篇 |
1976年 | 4篇 |
1972年 | 3篇 |
排序方式: 共有8784条查询结果,搜索用时 31 毫秒
51.
目的:研究枸杞地黄汤对老年小鼠学习记忆、自由基及免疫系统的影响。方法:采用水迷宫行为实验检测枸杞地黄汤对老年小鼠学习记忆的影响,通过测定皮层、海马中MDA和SOD水平检测药物对老年小鼠自由基系统异常改变的影响,通过测定老年小鼠免疫器官指数变化检测药物对老年免疫系统异常改变的影响。结果:5、10、20g/kg的枸杞地黄汤不同程度减小老年小鼠学习记忆障碍,降低皮层、海马中MDA水平,增加SOD活性,提高胸腺、脾指数。结论:枸杞地黄汤能够改善老年小鼠学习记忆障碍.调节不正常自由基系统和免疫系统。 相似文献
52.
男性不育患者精浆尿酸的检测及临床意义初探 总被引:4,自引:1,他引:3
目的 :检测男性不育患者精浆尿酸的含量 ,并探讨其与不育的关系。 方法 :2 0 0 3年 2~ 8月就诊的男性不育患者 1 6 3例 ,分为 4组 :梗阻性无精子症组 ,1 5例 ;非梗阻性无精子症组 ,36例 ;少精子症组 ,4 3例 ;弱精子症组 ,6 9例。 2 0例正常生育男性为正常对照组。上述各组均作精液参数分析及精浆尿酸含量的测定。 结果 :正常对照组精浆尿酸含量为 (396 .9± 5 3.1 ) μmol/L ,显著高于梗阻性无精子症组 [(79.5± 1 8.1 ) μmol/L]、非梗阻性无精子症组[(2 4 5 .8± 76 .5 ) μmol/L]、少精子症组 [(2 6 2 .2± 79.2 ) μmol/L]和弱精子症组 [(2 5 1 .4± 75 .4 ) μmol/L](P均 <0 .0 1 )。其中 ,梗阻性无精子症组精浆尿酸含量又显著低于其他各不育症组 (P均 <0 .0 1 ) ,其余各不育症组间精浆尿酸含量差异无显著性 (P >0 .0 5 )。 结论 :精浆中尿酸作为生殖系统中的一种重要抗氧化物 ,可能在男性生殖中具有一定意义。 相似文献
53.
I. D. MORRIS C. W. BARDIN G. GUNSALUS J. A. WARD 《International journal of andrology》1990,13(3):180-189
We examined the hypothesis that induction of reversible testicular atrophy, subsequent to withdrawal of gonadotrophin support, would alleviate the testicular toxicity of the anti-cancer drug procarbazine. In rats, severe but reversible testicular atrophy and suppression of spermatogenesis were induced 56 days after the subcutaneous insertion of a silastic implant containing oestradiol-17 beta. The effect of this treatment upon the testicular toxicity of four weekly doses of procarbazine (200 mg kg-1) was examined 56 days after the termination of procarbazine/oestrogen treatment. At this time the testicular endocrine and spermatogenic functions were close to normal in rats which has received only oestradiol-17 beta. Procarbazine produced severe testicular atrophy which was associated with azoospermia and destruction of the germinal epithelium. Serum LH and FSH concentrations were raised and were associated with low serum concentrations of both testosterone and androgen-binding protein. The combination of procarbazine with the oestrogen treatment did not change any of the testicular toxicity and in some cases it appeared to be exacerbated. In contrast to these experiments other studies have indicated that the testis can be protected if spermatogenesis is reversibly suppressed by other agents which are also active via the pituitary endocrine system. The data would therefore suggest that protection is achieved either by some testicular change other than withdrawal of pituitary gonadotrophin support or that oestradiol-17 beta has additional activity which is permissive for the development of the testicular toxicity of procarbazine. 相似文献
54.
The present paper reports 11 cases of light chain disease (LCD) sequently found in several citles over Fujian province, Immunological classification of this group of LCD ww as follows: six of me cases belonged to type λ, four of them were type κ, and another one was a double LCD. We found that LCD was common in Fujlan only next to multiple myeloma (MM) of IgG class and accounted for 20% of the total 55 MM cases found in recent yean.It to well known that In matt patients of LCD M protein or Bence Jones proteinemia (BJPemia) to not detectable by conventional electro-phoresis. Our studies show that by making serum protein along with urinary BJP electrophoresis on the same one gel plate the sltuation can be greatly Improved It not only favour* the recognition of smail and faint band or bands of free light chain in serum, but also provides a repid and sensitive way, i. e. , immunofixation, to directly detect urinary light chain on the gel plate Immediately after electrophresis has been run. 相似文献
55.
目的探讨女方不明原因流产和不明原因不孕与其配偶精子染色质性状之间的关系;方法通过精子染色质结构分析(SCSA)对22例不明原因流产和36例不明原因不孕妇女配偶精子,以及20例正常对照者精子进行DNA完整性检测,并比较它们之间的差异;结果对照组与不明原因流产组以及不孕组之间精子DNA完整性存在差异,且差异具有统计学意义(P<0.05),而不明原因流产组与不孕组之间精子DNA完整性比较无明显差异(P>0.05);结论精子染色质结构分析有可能作为不明原因流产和不孕的辅助诊断方法在临床应用。 相似文献
56.
用复方泛影葡胺注射液对1,020例不孕症者作子宫输卵管造影。结果:子宫腔形态异常540例。双侧输卵管通畅但形态异常者268例。单侧输卵管通畅但形态异常者110例。结果表明:子宫输卵管形态异常与不孕有密切关系。 相似文献
57.
选择46例晚期肺癌患者应用LAK/IL-2疗法观察患者近期临床改善情况及治疗前后其免疫指标的变化情况。选择胎儿胸腺淋巴组织作前体细胞,体外用重组IL-2诱导制备LAK细胞,每输3次LAK细胞为1疗程,每次输入细胞数为05×109,化疗以采用丝裂霉素、长春新碱、顺铂或卡铂、鬼臼乙叉甙为主的方案,治疗结果:本组患者治疗有效率(CR+PR)达70%,同时患者免疫指标好转。本研究提示LAK/IL-2联合疗法临床近期疗效较满意,同时可显著改善机体免疫功能,是晚期肺癌患者一种可行的有效方法 相似文献
58.
This case report presents a very rare and long-standing causeof infertility, osseous metaplasia of the endometrium, and describesits successful management by hysteroscopy. A woman with a historyof induced abortion 12 years ago, failed to conceive from thattime on. The infertility work-up was unrevealing except forthe presence of intracavitary calcification on ultrasonography.After diagnostic hysteroscopy, solid bony spicules coveringthe posterior wall of the endometrial cavity were removed bywire loop resectoscope. Histology established the diagnosisof osseous metaplasia of the endometrium. The patient conceivedin her second spontaneous cycle and has an ongoing pregnancyat the time of writing. Hysteroscopy was an effective meansof extracting this heterotopic tissue, thereby re-establishingfertility even after a long period of infertility. 相似文献
59.
Erenpreiss J Jepson K Giwercman A Tsarev I Erenpreisa J Spano M 《Human reproduction (Oxford, England)》2004,19(10):2277-2282
BACKGROUND: Sperm DNA integrity (SDI) is an important factor in the prognosis of male fertility. Here we compare the toluidine blue (TB) image cytometry test, recently proposed by us for SDI assessment, with two other tests-the sperm chromatin structure assay (SCSA) and the terminal nick-end labelling (TUNEL) assay. METHODS: Sperm samples from 35 men were evaluated for standard sperm parameters and subjected to the TB test and SCSA. Eighteen of the 35 samples were also subjected to the TUNEL assay. RESULTS: The proportion of sperm cells with abnormal DNA integrity assayed by the TB test correlated strongly with the proportion of abnormal cells detected by the SCSA and TUNEL assay (rho=-0.84 and rho=0.80, P<0.001, respectively). Furthermore, the fractions of abnormal cells by the TB test corresponded closely to the sum of two SCSA parameters, the DNA fragmentation index (DFI) and the fraction of highly DNA-stainable cells (HDS) (medians 33.0 versus 32.0%, P=0.6). CONCLUSIONS: Abnormal cells in a TB test correspond to the sum of DFI and HDS fractions in the SCSA. TB-positive cells may represent sperm with fragmented DNA and/or abnormal chromatin structure. Because the TB test is an easy and inexpensive method, its potential use as a routine test for sperm DNA integrity, complementary to standard semen parameters, should be investigated further. 相似文献
60.
目的探讨无精子症,严重少精子症和少、弱精子症患者的遗传缺陷与男性不育的关系。方法采用外周血染色体核型分析技术和Y染色体基因微缺失检测方法,对120例无精子症,严重少精子症和少弱精子的患者进行了遗传咨询。结果在被筛查患者中发现异常染色体核型13例,异常核型发生率为10.83%;而其Y染色体微缺失检测中存在AZFc/SPGY基因缺失31例,缺失率25.83%。结论染色体核型异常和Y染色体微缺失与精子生成障碍有直接逻辑关系。Y染色体AZFc/SPGY区域的微缺失是中国男性不育的重要原因,因此,中国男性不育症患者有必要进行Y染色体AZFc/SPGY微缺失的常规筛查。 相似文献