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81.
Our objective was to correlate p16, p21cip1, p27kip1, and cyclin E protein expression with the degree of dysplasia on ThinPrep Papanicolaou (Pap) smears using a modified immunoperoxidase staining. Smears read as normal, atypical squamous cells of undetermined significance (ASC-US), low-grade squamous intraepithelial lesion (LSIL), or high-grade SIL (HSIL) were identified and tested for high-risk human papillomavirus (HR-HPV). Additional smears were processed for immunoperoxidase for p16, p21cip1, p27kip1, and cyclin E. Thirty-four smears were satisfactory for study. The p16 was positive in all nine HSIL, in four of nine LSIL, and in one of seven ASC-US. The p27kip1 was positive in all nine HSIL, in eight of nine LSIL, and in one of seven ASC-US. The p21cip1 was positive in all nine HSIL, in one of nine LSIL, and in one of seven ASC-US. Cyclin E was positive in seven of nine HSIL and in one of nine LSIL and in none of the ASC-US smears. Normal smears were negative for all the antigens. There was poor correlation of protein expression and HR-HPV infection. We concluded that p16, p21cip1, p27kip1, and cyclin E can be demonstrated on Pap smears and they are expressed differentially in dysplastic cells, with highest expression in HSIL. The p21cip1 and cyclin E showed the greatest correlation with HSIL.  相似文献   
82.
The indirect immunofluorescent method was employed to investigate the distribution of neuronal nitric oxide synthase-like immunoreactivity(nNOS-LI) in the spinal cord of the golden hamster and to compare it to data obtained from rats. Immunoreactive neurons were found throughout the cervico-sacral extent in the dorsal horn (mainly in laminae I-III) and in the preganglionic autonomic regions, i.e., the sympathetic intermediolateral nucleus (IML), lateral funicle (LF), intercalated region (IC), the area surrounding the central canal (CA), and the sacral preganglionic parasympathetic cell group. While the distribution of immunoreactive cells was generally similar in both species, some differences were observed. For example in the hamster LF, a higher percentage of stained neurons was seen than in the IML, while the situation was rather inverse in the rat. In order to study the coincidence of nNOS-LI in the population of preganglionic sympathetic neurons (PSN) that innervate the superior cervical ganglion (SCG), these were identified by retrograde axonal transport of fluoro-gold (FG) following unilateral injection into the SCG. PSN were localized ipsilateral to the injection site mainly in the IML and LF of spinal segments C7-Th4. The portion of double-labeled neurons of the IML were lower in hamster (17% in C7, 34% in C8) of FG-labeled cells) than in rat (47% in C8, 77% in Th2), while in the LF of segments C8-Th2 in both species the majority of FG-neurons contained nNOS. While only very few double-labeled neurons were detected in the IC in hamster and rat, a striking difference was observed in the CA, where no double-labeled neurons were found in hamster, but up to 50% in rat. Double immunofluorescence detection of nNOS and substance P (SP) showed that in both the autonomic regions and the dorsal horn, SP-LI fibers and puncta were present in close spatial relationship to nNOS-LI cell bodies. These results were basically identical in the hamster and rat. Unilateral transection of the dorsal roots of segments C6-Th2 in rats resulted in a clear reduction of SP-LI structures in the dorsal horn 5 days after rhizotomy, but not in the autonomic regions. Compared to the unlesioned side, the numbers of nNOS-LI neurons in the superficial laminae of the dorsal horn were reduced to 32-46% in the lesioned segments, and to 53% and 87%, respectively, in the two segments cranial to the rhizotomized segments but remained unchanged caudally to the lesion. Numbers of nNOS-LI cell bodies in the autonomic regions were not altered following dorsal root transection. The present study provides data on the widespread distribution of nNOS in the spinal cord of golden hamster and describes the partial coincidence of the enzyme in PSN. The effects of dorsal rhizotomy on nNOS-LI neurons in the dorsal horn reveal that primary-afferent fibers provide a stimulatory influence on neurons of the dorsal horn to generate the gaseous neuroactive substance, nitric oxide.  相似文献   
83.
目的 明确颈深筋膜的分层及筋膜间隙的位置、毗邻 ,为颈深筋膜间隙的影像识别与分析提供参考 ,为临床诊治感染蔓延、肿瘤侵润提供解剖学依据。 方法 采用低温冰冻和生物塑化技术用 17例标本 ,制作了颈部连续薄层横断面 ,对颈深筋膜及筋膜间隙进行了观测。从颈部薄层塑化断面标本上 ,用双线提取间隙轮廓的方法 ,在SGI工作站上对颈深筋膜间隙进行三维重建。 结果  1.颈深筋膜应分为四层 ,颈深筋膜深层分为翼筋膜和椎前筋膜 ,颈深筋膜各层均参与颈动脉鞘的形成。 2 .颈动脉间隙是一开放的间隙 ,其后外侧与颈后间隙相通 ;证实了危险间隙的存在。 3.重建出咽后间隙、颈动脉间隙和内脏间隙的三维图像 ,并能同时显示间隙内的主要结构。结论 得出了颈深筋膜和筋膜间隙的模式图 ,并为筋膜间隙的三维重建提供了一种新的方法。  相似文献   
84.
人宫颈癌细胞产生的免疫抑制因子(TDSF)作用于人外周血单个核细胞(PBMC)6h,即可抑制白细胞介素2(IL-2)产生,与对照组相比,P<0.01。当TDSF存在时,经PHA-P驯化的PBMC效应细胞对外源性IL-2反应显著减弱,表明TDSF能抑制IL-2的作用。PHA-P刺激PBMC增殖,但TDSF使其增殖抑制。表明TDSF能抑制IL-2产生及其作用;抗癌药对TDSF的分泌有部分阻抑作用。  相似文献   
85.
CAM 5.2 is a monoclonal antibody which identifies lower molecular weight cytokeratin proteins (50, 43 and 38 kD). It is an antibody which works reliably on formalin-fixed, paraffin-embedded tissues. In this study, using CAM 5.2 in the indirect immunoperoxidase method we have examined ectocervical epithelium ranging from normal, through metaplasia and cervical intraepithelial neoplasia to invasive squamous carcinoma. CAM 5.2 is demonstrated to be a useful indicator of changes associated with malignant transformation in the ectocervix.  相似文献   
86.
目的 探讨术前颈椎过伸功能与颈椎后路单开门椎管扩大成形术后前凸角度丢失的关系。方法 回顾性分析首都医科大学大兴教学医院骨科2017年1月-2018年12月58例行颈椎后路单开门椎管扩大成形术患者临床资料,其中男45例、女13例,年龄49~85岁(平均64.8岁)。术前测量患者中立侧位X线片上的T1倾斜角、矢状面垂直轴(SVA),以及中立侧位、过伸位X线片的C2~C7 Cobb角。随访12~24个月,术后再次测量中立侧位X线片上的C2~C7 Cobb角。术前颈椎过伸功能测量值为术前过伸位X线片C2~C7 Cobb角度减去术前中立侧位X线片C2~C7 Cobb角。前凸角度丢失量为术前中立侧位片C2~C7 Cobb角减去末次随访时中立侧位片C2~C7 Cobb角。依据58例患者术前颈椎过伸功能均值(8.7°)分为两组,≥8.7°为A组,<8.7°为 B 组。比较两组患者术前及术后影像及临床资料,同时对58例患者的影像学资料与临床资料进行相关性分析。结果 A组25例患者年龄54~83岁,B组33例患者年龄49~85岁,两组患者术前年龄、性别、疾病种类差异均无统计学意义(P值均>0.05)。术前A组颈椎过伸功能(14.09°±4.75°)大于B组(4.62°±2.54°),A组T1倾斜角(17.00°±3.40°)小于B组(29.68°±6.34°),颈椎前凸角度丢失[1.10(-0.85,4.00)]小于B组[8.60 (7.70,12.40)],差异均有统计学意义(P值均<0.01)。颈椎过伸功能与前凸角度丢失之间呈负相关(r=-0.965, P<0.01),T1倾斜角与前凸角度丢失之间呈正相关(r=0.954, P<0.01),颈椎过伸功能与T1倾斜角呈负相关(r=-0.900, P<0.01);SVA与T1倾斜角、颈椎过伸功能、术后前凸角度丢失均无相关性(r=-0.065、0.216、-0.202, P>0.05)。术后JOA评分改善率与过伸角度变化、SVA及T1倾斜角均无相关性(r=0.201、-0.034、-0.213, P值均>0.05)。A组术后JOA改善率为69%±23%,B 组术后JOA改善率为62%±23%,两组差异无统计学意义(t=1.147, P>0.05)。术后Odom's分级评价A组优良率为88.0%(22/25),B组优良率为63.6%(21/33),差异有统计学意义(χ2 =4.403, P<0.05)。结论 对于后路单开门椎管扩大成形术患者,颈椎过伸功能与前凸角度丢失存在相关性,术前过伸功能越低,术后越易发生前凸角度丢失,可作为术前预判术后颈椎曲度变化的参数之一。  相似文献   
87.
BACKGROUND: This study was conducted on human cervical mucus using light microscopy (LM) and scanning electron microscopy (SEM). The objective was the morphological characterization of the different mucus types, with samples taken from the lumen of the cervix and from the different secretory zones of the cervical mucosa. METHODS: A total of 230 samples from 195 women were spread out on slides and air dried. The phenomenon of 'ferning' was observed and assessed in these samples using both LM and SEM. Further samples from the lumen of the cervix and the different secretory crypts were spread out on cover slips and fixed with glutaraldehyde (2.5%) to be studied by SEM. RESULTS: The results show the presence of four different morphological mucus types, namely L, S, P and G, in both types of sample using dried and fixed techniques. CONCLUSIONS: Mucus from the lumen of the cervix appears to be a morphologically heterogeneous entity. It contains different types of secretions, the proportions of which vary throughout the menstrual cycle. The different mucosal types show different types of crystallization, different patterns of ultrastructure (probably related to the arrangement of the glycoprotein network) and are produced in different secretory zones of the crypts in the cervix.  相似文献   
88.
The present study was undertaken to evaluate the systemic absorption and cervical tissue uptake of all-transretinoic acid (TRA), delivered via a collagen spongecervical cap delivery device in patients with intraepithelial cervical dysplasia. Ten patients with histologically proven mild or moderate cervical dysplasia were included in this pharmacologic study. The two TRA concentrations (0.05% and 0.372%) selected for study represent the starting and maximally tolerated doses used in phase I clinical trial. All-trans-retinoic-11-3H acid (3H-TRA, 500 Ci) was used to facilitate cervical tissue uptake studies. Cervical biopsies and post-treatment blood samples were obtained from each patient after TRA exposure. The uptake of TRA into cervical tissues four hours after drug administration was significantly increased at the maximally tolerated TRA dose. There was a rapid decrease in cervical tissue concentration of TRA at the 0.372% dose between 4 and 24 h after drug exposure, suggesting a relatively short elimination half-life of TRA in cervical tissues. HPLC analysis of post-treatment blood samples indicate that there was no systemic absorption of TRA after local cervical administration.  相似文献   
89.
Summary The effect of bath-applied adenosine on transmission in the isolated superior cervical ganglion of the rat was investigated. The compound post ganglionic action potential was recorded as an index of ganglionic transmission. Adenosine and 2-chloroadenosine were equipotent in producing a dose-dependent inhibition of the amplitude of the compound action potential. At the highest concentration tested (1 mM) adenosine and 2-chloroadenosine produced about 30% decrease in the amplitude of the compound action potential. This inhibitory effect was antagonized by theophylline (1 and 100 M) which by itself had no significant effect on ganglionic transmission. The adenosine uptake blocker dipyridamole (1 and 100 M) failed to potentiate the inhibitory action of adenosine. Both 4-aminopyridine (20 M) and high frequencies of stimulation (3, 10 and 20 Hz) were effective in nearly completely abolishing the inhibitory effect of adenosine on ganglionic transmission.The results suggest that the inhibitory effect of adenosine on ganglionic transmission may be the result of activation of presynaptic adenosine receptors in the ganglion.  相似文献   
90.
宫颈癌是最常见的妇科恶性肿瘤之一。目前人乳头瘤病毒(HPV)检测及细胞学检查是宫颈癌及其癌前病变(CCPL)的主要筛查手段。由于上述传统筛查方法,仍然存在对CCPL漏诊的风险,因此寻找有效识别CCPL的特异性分子标志物,具有重要临床意义。对具有序列相似性家族19成员A4(FAM19A4)基因启动子甲基化定量检测,可有效检出CCPL组织,较传统筛查方法有较高特异度,有望成为CCPL筛查的特异性分子标志物。笔者拟就FAM19A4基因启动子甲基化定量检测,在CCPL筛查中应用的最新研究现状进行阐述,旨在为进一步推进CCPL筛查方法的开发,提供思路。  相似文献   
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