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21.
老年认知功能障碍与脑结构CT测量的相关性研究 总被引:1,自引:1,他引:0
目的探讨脑萎缩与老年认知功能障碍之间的相关性。方法对开滦集团公司1063名离退休职工进行健康查体,用简易精神状态量表(MMSE)评定认知功能,按分界值将本次研究对象分为认知功能障碍组和认知功能正常组,同时用CT线性测量脑的相关部位以诊断脑萎缩情况,并对各型脑萎缩与认知功能的相关系数及提示老年认知功能障碍的敏感度、特异度、准确度进行分析。结果1063名观察对象中符合入选标准并资料完整者共计511名,其中108名有认知功能障碍,髓质脑萎缩55名、皮质萎缩5名、混合型萎缩30名;认知功能正常者403名,髓质脑萎缩214名、皮质萎缩13名、混合型萎缩62名。认知功能障碍组脑萎缩的发病率高于认知功能正常组,差异具有统计学意义(P<0.005);2组间颞叶海马钩回间距(26.86mm±3.73mmvs25.95mm±3.80mm)及海马钩回间距/大脑左右径的比值(0.21±0.02vs0.20±0.02)差异具有统计学意义(P<0.05);海马钩回间距、皮质脑萎缩、混合型脑萎缩与认知功能障碍呈负相关(分别为r=-0.094,P=0.034,r=-0.156,P≈0.000,r=-0.147,P≈0.000),以海马钩回间距20mm提示老年认知功能障碍的敏感度最高(98.14%),混合型脑萎缩的特异度(84.86%)、准确度最高(72.80%)。结论CT测量相关脑结构,判断脑萎缩类型可以为老年认知功能障碍的诊断提供有价值的信息。 相似文献
22.
Although breast milk is recommended as the optimal source of infant nutrition, breastfeeding initiation is below recommended levels, especially among teenage mothers. Breastfeeding initiation rates among Michigan (US) teenage mothers (12-19 y) were compared by demographics and health behaviors. Multivariate analyses determined which factors were significant independent predictors of breastfeeding initiation among teenage mothers enrolled prenatally in the Michigan Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) program in 1995. Significant predictors independently associated with breastfeeding initiation were race/ethnicity, education, marital status, postpartum anemia status, parity, prenatal trimester of WIC enrollment, and smoking. The strongest predictor of breastfeeding initiation differed for white mothers (positive predictor: education beyond high school [OR = 3.13]) and black mothers (negative predictor: multiparous [OR = 0.25]). Initiation rates for this population of teenage mothers fall below the national average for mothers of all ages and the US Healthy People 2010 goals. Research is needed concerning how breastfeeding support and education can be improved to reach the US national health goals. 相似文献
23.
单甲氧聚乙二醇化学修饰药物酶的研究进展 总被引:4,自引:0,他引:4
用单甲氧基聚乙二醉(1)化学修饰药物酶是生化药物研究开发的重要手段之一。本文综述了1化学修饰药物酶的一般方法及修饰后酶在生物和理化性质方面的变化,同时对1研究前景进行展望,并指出了尚待解决的问题。 相似文献
24.
Importance of an immunodominant surface-exposed loop on outer membrane protein P2 of nontypeable Haemophilus influenzae. 总被引:1,自引:1,他引:0 下载免费PDF全文
Nontypeable Haemophilus influenzae (NTHI) frequently causes recurrent infections of the respiratory tract in humans. Previous indirect evidence suggested that a strain-specific immune response occurs following infection and that this immune response is directed at an immunodominant epitope on the bacterial surface. To test this hypothesis, mice and rabbits were immunized with whole cells of a strain of NTHI and the antiserum was characterized to identify the antigens to which antibodies were directed. All animals made a prominent antibody response to the loop 5 region of the P2 molecule, which is the major outer membrane protein. Rabbit serum showed complement-dependent bactericidal activity. Adsorption of the immune serum with the loop 5 fusion peptide removed bactericidal activity and also abolished reactivity to P2 detected by an immunoblot assay, an enzyme-linked immunosorbent assay, and a radioimmunoprecipitation assay. These data indicate that immunization with whole cells of NTHI results in a prominent antibody response which is directed at epitopes on the loop 5 region of the P2 molecule. Thus, a strain-specific immune response to NTHI occurs as a result of the expression of an immunodominant epitope on the P2 molecule. 相似文献
25.
本文对44例牙源性脓肿(尖周脓肿24例,牙周脓肿12例,冠周脓肿8例)脓液标本中的产黑色素类杆菌群菌株进行分离、培养、鉴定。其中38例存在产黑菌群,以中间型类杆菌阳性率最高。牙龈类杆菌在牙周脓肿中检出率最高。24例尖周脓肿可分离出6株牙髓类杆菌而其它两种牙源性脓肿则无牙髓类杆菌,推测该菌与牙髓尖周感染的病理过程有关。 相似文献
26.
Identification of Leishmania donovani isolates from different kala-azar foci in China by kDNA hybridization. 总被引:1,自引:0,他引:1
kDNA sequence homology of Leishmania donovani isolates from three types of kala-azar foci in China were analyzed by using dot and Southern hybridization with biotin- and 32P-labelled probes. The results revealed kDNA sequence heterogeneity among Leishmania donovani isolates from the three kala-azar foci: sequence homology between isolates of hill and desert foci was higher than that between hill and plain foci isolates. The kDNA hybridization technique was also found to be specific and sensitive for direct identification of Leishmania in animal tissues. In a preliminary survey, kDNA hybridization of cutaneous tissue blots of 71 dogs from endemic regions showed a positive rate of 40.8%, and the rate of double positive cases (touch blot hybridization and bone marrow smear) reached 91.3%. The direct identification of Leishmania in tissues by kDNA hybridization seems to be a useful and convenient method for epidemiological study and clinical diagnosis, especially for species/strain characterization. 相似文献
27.
介绍一种用单片机构成的自动灌流控制系统。它以灌流压为控制指标,以LDB-M电子蠕动泵作为执行机构,构成闭环控制系统,能实现用户设定的各种液流压曲线。系统内采用了EEPROM存储器,可对用户设定的多达10条灌流曲线进行长期保存。 相似文献
28.
格林—巴利综合征患者血清和脑脊液中的抗硫脂抗体 总被引:5,自引:1,他引:4
探讨抗硫脂抗体与格林-巴利综合征(GBS)的关系。方法采用固相酶联免疫吸附法对急性期GBS患者血清和脑脊液(CSF)中抗硫脂IgG和IgM抗体进行检测。结果GBS患者血清和CSF中抗硫脂IgG及IgM抗体的阳性率均明显高于正常对照组;血清中抗硫脂IgM抗体滴度与标本收集时患者发病天数呈负相关(P<0.05),而血清中抗硫脂IgG抗体滴度与临床分级(P<0.01)、CSF中抗硫脂IgG抗体滴度(P<0.01)呈正相关;血清中抗硫脂IgG或IgM阳性的GBS患者,体检时有不同程度的感觉障碍患者为56%,而血清中抗硫脂抗体阴性患者仅为16%,两者之间差异有显著意义(P<0.05)。结论抗硫脂抗体可能在GBS的病理过程中起重要作用 相似文献
29.
选择性髂内动脉结扎与栓塞对盆腔血供的影响 总被引:5,自引:0,他引:5
目的:旨在探讨选择性髂内动脉结扎与栓塞两种方法对盆腔血供的影响。方法:将两组犬在膀胱上动脉分支以下之髂内动脉分别行结扎与栓塞,对比观察两组膀胱创面出血、盆腔动脉造影及盆腔脏器组织学变化,以确定其盆腔脏器的血供情况。结果:①结扎组膀胱创面出血明显大于栓塞组;②结扎组髂内动脉侧支循环建立时间明显早于且数目多于栓塞组;③两组盆腔脏器均未见缺血坏死。结论:栓塞组阻断髂内动脉侧支循环的数目多于结扎组,故对盆腔血供的影响大于结扎组。避免髂内动脉阻断范围过广可减少盆腔脏器缺血坏死的机会。 相似文献
30.
Jiang He Mary Rusckowski Yi Wang Shuping Dou Xinrong Liu Surong Zhang Guozheng Liu Donald J. Hnatowich 《Molecular imaging and biology》2007,9(1):17-23
Objective Pretargeting with radioactivity has significantly improved tumor to normal tissue radioactivity ratios over conventional antibody
imaging in both animal studies and clinical trials. This laboratory is investigating DNA analogues such as phosphorodiamidate
morpholinos (MORFs) for pretargeting using technetium-99m (99mTc) for detection. However, the unique properties of fluorescence activation and quenching combined with oligomers with their
unique properties of hybridization may be particularly useful when used together for pretargeting with optical detection.
The use of linear fluorophore-conjugated oligomer duplexes have been little used in animals, and to our knowledge, have not
previously been considered for pretargeting applications.
Methods A MORF/cDNA pair was selected such that when hybridized, the fluorescence of the Cy5.5-conjugated 25 mer MORF (Cy5.5–MORF25)
is inhibited with a BHQ3-conjugated 18 mer complementary DNA (BHQ3–cDNA18). The short BHQ3–cDNA18 was selected to dissociate
in the presence of a long cMORF25 in the pretargeted tumor, thus releasing the inhibitor from the Cy5.5 emitter. In this manner,
the Cy5.5 fluorescence will be inhibited everywhere but in the target. The dissociation was first examined in vitro by adding the duplex to the cMORF25 both in solution and immobilized on polystyrene microspheres and by surface plasmon resonance
(SPR). Thereafter, biotinylated cMORF25 immobilized on streptavidin polystyrene microspheres were administered intramuscularly
in one thigh of hairless SKH-1 mice as target while an identical weight of the identical microspheres but without the cMORF25
was administered in the contralateral thigh as control. The animals then received IV the Cy5.5–MORF25/BHQ3–cDNA18 duplex or
equal molar dosage of single-chain Cy5.5–MORF25 and were imaged.
Results The SPR studies showed that the immobilized cDNA18 rapidly captured the flowing MORF25 to provide a duplex with a slow dissociation
rate constant. Furthermore, when cMORF25 was next allowed to flow over the now immobilized duplex, the cDNA18 was unable to
prevent dissociation of the heteroduplex and the formation and release of the cMORF25-MORF25 homoduplex. Images of animals
obtained soon after receiving the Cy5.5–MORF25 singlet showed intense whole body fluorescence obscuring the target thigh.
However, only 5 minutes after receiving the Cy5.5–MORF25/BHQ3–cDNA18 duplex, the target thigh was clearly visible along with
only the kidneys.
Conclusions This first study of optical pretargeting provides a proof of concept that oligomer pretargeting found to be useful with radioactivity
detection is applicable with fluorescent detection as well. In addition, our results demonstrate that by using linear oligomers
for optical pretargeting, chain lengths (and base sequences) may be manipulated to provide duplexes with stabilities and fluorescence
inhibition optimized for pretargeting and other in vivo applications of optical imaging. 相似文献