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101.
102.
目的 研究蛋白多糖在大鼠肠系膜淋巴结高内皮微静脉(HEVs)中的分布,探讨蛋白多糖在淋 巴细胞归巢过程中的调节作用。方法 阳性胶体铁染色—酶连续阻断法,光镜和电镜观察蛋白多糖于HEVs 内的淋巴细胞、内皮细胞、基膜上的分布。结果 HEVs的基膜和邻接基膜的淋巴细胞胞膜呈强阳性染色,能 被透明质酸酶、肝素酶、软骨素酶ABC阻断;电镜显示,胶体颗粒主要排列于基膜的内、外侧及穿越基膜的淋 巴细胞胞膜上,内皮细胞、穿内皮细胞的淋巴细胞和腔内的淋巴细胞不着色。结论 蛋白多糖于大鼠肠系膜 淋巴结HEVs内主要分布于基膜和穿基膜的淋巴细胞胞膜上,可能对归巢淋巴细胞穿越HEVs管壁有调节作 用。  相似文献   
103.
目的 通过三维CT血管成像(CTA)评估分析直肠癌患者肠系膜下动脉(IMA)分型及解剖特点,为直肠癌手术血管处理提供参考。 方法 回顾分析2018年1月至2019年12月华中科技大学同济医学院附属协和医院接受IMA CTA检查的直肠癌患者临床及影像学资料。通过三维CT血管成像重建IMA图像。对IMA进行分类并测量统计肠系膜下血管各解剖参数。 结果 266例研究对象中男性187例,女性79例。111例(41.7%)左结肠动脉(LCA)从主干独立发出,112例(42.1%)LCA和乙状结肠动脉(SA)共干发出,33例(12.4%)LCA、SA及直肠上动脉(SRA)共干,10例(3.8%)缺乏LCA。全组IMA主干长度(LIMA)为(39.1±10.1)mm、IMA根部至髂血管分叉距离(DIMA)为(44.1±7.4)mm、IMA根部与肠系膜下静脉(IMV)水平距离为(24.6±8.9)mm、IMA分支点与IMV水平距离为(13.0±5.3)mm。LCA走行包括:122例(47.6%)高位型,88例(34.4%)中位型,46例(18.0%)低位型。65例(25.4%)LCA紧贴IMV内侧,136例(53.1%)LCA紧贴IMV外侧,55例(21.5%)LCA外侧远离IMV。 结论 术前利用三维CT血管成像可准确评估IMA分型及肠系膜下血管的形态走行关系,为直肠癌手术中血管处理提供指导。  相似文献   
104.
目的以健康人群为研究对象,探讨肠系膜淋巴结在薄层螺旋CT图像上的分布特点及其临床意义。方法选择60例健康体检者,其中男性35例,女性25例;年龄26~67岁,平均年龄55岁。用Siemens Definition AS 128层螺旋CT进行腹部扫描,成像参数:120 kV,280 mA,128 i×0.6 mm,0.5 s/r,螺距0.6,扫描层厚、层间距均为8 mm。由3名放射学工作者应用同一图像贮存和传输系统(PACS)工作站阅读所有CT图像,记录所有短轴大于3 mm的肠系膜淋巴结的大小、数目及位置(肠系膜根部、周边肠系膜或右下腹肠系膜区)。结果有54例检测到短轴直径大于3 mm肠系膜淋巴结,其中12例(22.2%)检测到10个以上淋巴结,31例(57.4%)检测到5个以上淋巴结,其余11例(20.4%)检测到5个以下淋巴结。同时所有体检者都检测到多个短轴直径小于3 mm的肠系膜淋巴结,短轴直径多为2 mm左右。在所有检测到的淋巴结中,最大淋巴结直径范围为5.4~9.2 mm,平均直径范围为3.5~6.5 mm。54例中,肠系膜根部发现较多淋巴结者25例(46.3%),右下腹肠系膜区22例(40.7%),肠系膜周边部7例(13.0%)。结论128层螺旋CT能检出更多、更小的肠系膜淋巴结。这些淋巴结直径可小于3 mm。在健康人群中发现这些淋巴结,无临床意义,不需要进一步的影像学检查及临床治疗。  相似文献   
105.
目的阐明腹腔镜右半结肠切除术(laparoscopic right hemicolectomy,LRH)相关血管的活体解剖学特点。方法对36例接受LRH的肿瘤病人进行术中观察和术后录像复习。结果肠系膜上静脉(superior mesenteric vein,SMV)为起于右髂窝上缘,位于小肠系膜和升结肠系膜交界部的蓝色条纹。肠系膜上动脉在系膜内难以目视辨认,走行于SMV左侧。回结肠血管出现率100%,为升结肠系膜内、十二指肠水平部下缘附近、搏动的条索。胃结肠干出现率77.8%(28/36),包含上右结肠静脉/右结肠静脉者占比为89.3%(25/28);后者亦可直接注入SMV。胃结肠干于胰切迹右缘的横结肠后间隙汇入SMV右壁。右结肠动脉在胰颈下缘起始,常与胃结肠干伴行或交叉。结论正确的间隙(肠系膜内间隙)、标志和线索(肠系膜上静脉),是LRH中血管定位的解剖学基础。  相似文献   
106.
An atypical case of abdominal vasculature, found in a 58-year-old woman is presented. The multidetector computed tomography angiogram revealed a large tortuous anastomotic vessel between the stem of the celiac trunk and the left colic artery, supplying branches for the left colon and pancreatic body and tail. We propose a simple embryological explanation for the development of this aberrant artery--the longitudinal ventral anastomosis, which connects the precursors of principal visceral arteries in a loop-like manner, loses its direct communication with the superior mesenteric artery but maintains its continuity above and below this level. This variation could pose a problem for radiological interpretation and affect surgical approaches to the aorta, left colon, and the pancreas.  相似文献   
107.
《Immunology》2017,152(1):52-64
Dendritic cells (DCs) in mesenteric lymph nodes (MLNs) induce Foxp3+ regulatory T cells to regulate immune responses to beneficial or non‐harmful agents in the intestine, such as commensal bacteria and foods. Several studies in MLN DCs have revealed that the CD103+ DC subset highly induces regulatory T cells, and another study has reported that MLN DCs from programmed death ligand 1 (PD‐L1) ‐deficient mice could not induce regulatory T cells. Hence, the present study investigated the expression of these molecules on MLN CD11c+ cells. Four distinct subsets expressing CD103 and/or PD‐L1 were identified, namely CD11b+ CD103+ PD‐L1High, CD11b CD103+ PD‐L1High, CD11b CD103+ PD‐L1Low and CD11b+ CD103 PD‐L1Int. Among them, the CD11b CD103+ PD‐L1High DC subset highly induced Foxp3+ T cells. This subset expressed Aldh1a2 and Itgb8 genes, which are involved in retinoic acid metabolism and transforming growth factor‐β (TGF‐β) activation, respectively. Exogenous TGF‐β supplementation equalized the level of Foxp3+ T‐cell induction by the four subsets whereas retinoic acid did not, which suggests that high ability to activate TGF‐β is determinant for the high Foxp3+ T‐cell induction by CD11b CD103+ PD‐L1High DC subset. Finally, this subset exhibited a migratory DC phenotype and could take up and present orally administered antigens. Collectively, the MLN CD11b CD103+ PD‐L1High DC subset probably takes up luminal antigens in the intestine, migrates to MLNs, and highly induces regulatory T cells through TGF‐β activation.  相似文献   
108.
The present study was designed to investigate involvement of angiotensin II (Ang II) type 2 receptors (AT2 receptors) in restoration of perivascular nerve innervation injured by topical phenol treatment. Male Wistar rats underwent in vivo topical application of 10% phenol around the superior mesenteric artery. After phenol treatment, animals were subjected to immunohistochemistry of the third branch of small arteries, Western blot analysis of AT2 receptor protein expression in dorsal root ganglia (DRG) and studies of mesenteric neurogenic vasoresponsiveness. Ang II (750 ng/kg/day), nerve growth factor (NGF; 20 microg/kg/day) and PD123,319 (AT2 receptor antagonist; 10 mg/kg/day) were intraperitoneally administered for 7 days using osmotic mini-pumps immediately after topical phenol treatment. Losartan (AT1 receptor antagonist) was administered in drinking water (0.025%). Phenol treatment markedly reduced densities of both calcitonin gene-related peptide (CGRP)-like immunoreactivity (LI) and neuropeptide Y (NPY)-LI-containing fibers. NGF restored densities of both nerve fibers to the sham control level. Coadministration of Ang II and losartan significantly increased the density of CGRP-LI-fibers but not NPY-LI-fibers compared with saline control. The increase of the density of CGRP-LI-fibers by coadministration of Ang II and losartan was suppressed by adding PD123,319. Coadministration of Ang II and losartan ameliorated reduction of CGRP nerve-mediated vasodilation of perfused mesenteric arteries caused by phenol treatment. The AT2 receptor protein expression detected in DRG was markedly increased by NGF. These results suggest that selective stimulation of AT2 receptors by Ang II facilitates reinnervation of mesenteric perivascular CGRP-containing nerves injured by topical phenol application in the rat.  相似文献   
109.
A.P. Gesase   《Annals of anatomy》2007,189(1):53-58
The current observations have documented rare vascular anomalies in the right and left kidneys from a male and female cadaver, respectively. In the female left kidney in addition to being supplied by the normal renal artery and vein it contained a left lower polar renal artery and vein. The polar artery took origin from the inferior mesenteric artery to supply the lower pole and was drained by the left lower polar vein that opened into the left common iliac vein. The right kidney from a male cadaver showed supernumerary renal arteries and veins. The supernumerary upper renal artery took origin from the aorta and after a short course it gave rise into a cranial branch that took a long course to supply the lower pole and a caudal branch that entered the right kidney at the hilum. The supernumerary lower renal artery also took origin from the aorta and passed to supply the lower pole of the right kidney. Therefore, the lower pole of the right kidney received two arteries, but was not associated with a polar vein. The right kidney in addition to the normal right renal vein contained a supernumerary right renal vein. The vein was seen at the hilum and was the most posterior structure; passing behind the supernumerary lower renal artery to open into the posterior surface of the inferior vena cava. The anomalies described in the current observation present a unique pattern of congenital renal vascular abnormalities that may be of surgical importance.  相似文献   
110.
Our previous report showed that innervation of calcitonin gene-related peptide (CGRP)- and neuropeptide Y (NPY)-containing nerves in rat mesenteric resistance arteries was markedly reduced by topical application of phenol, and that nerve growth factor (NGF) facilitates the reinnervation of both nerves. We also demonstrated that a CGRP superfamily peptide, adrenomedullin, is distributed in perivascular nerves of rat mesenteric resistance arteries. In the present study, we investigated the influence of adrenomedullin on the reinnervation of mesenteric perivascular nerves following topical phenol treatment. Under pentobarbital-Na anesthesia, 8-week-old Wistar rats underwent in vivo topical application of phenol (10% phenol in 90% ethanol) to the superior mesenteric artery proximal to the bifurcation of the abdominal aorta. After the treatment, the animals were subjected to immunohistochemistry of the third branch of small arteries proximal to the intestine and to vascular responsiveness testing on day 7. Topical phenol treatment caused marked reduction of the density of NPY-like immunoreactive (LI)- and CGRP-LI nerve fibers in the arteries. Adrenomedullin (360 or 1000 ng/h) or NGF (250 ng/h), which was administered intraperitoneally for 7 days using an osmotic mini-pump immediately after topical phenol treatment, significantly increased the density of CGRP-LI- and NPY-LI nerve fibers compared with saline. Treatment with adrenomedullin (1000 ng/h) or NGF restored adrenergic nerve-mediated vasoconstriction and CGRP nerve-mediated vasodilation in the perfused mesenteric artery treated topically with phenol. These results suggest that adrenomedullin, like NGF, has a facilitatory effect on the reinnervation of perivascular nerves.  相似文献   
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