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61.
Aneurysms are uncommon in the pediatric age-group. Unlike adults, in which aneurysms appear after alteration of the arterial wall due to systemic diseases, in children the traumatic etiology has to be considered: blunt trauma may disrupt the arterial wall and cause false aneurysm (pseudoaneurysm). Most aneurysms are asymptomatic, or they present as a pulsatile mass on an arterial traject. Diagnosis is confirmed with Doppler ultrasound and angiography. We present the case of a girl who, after blunt trauma of the right upper limb developed a pulsatile mass on the traject of the right humeral artery. Doppler ultrasound and angiography confirmed aneurysm of the humeral artery. She was successfully treated with surgical resection of the aneurysm and reconstruction of the arterial wall.  相似文献   
62.
Myelodysplastic syndromes and acute myeloid leukemia (AML) are heterogeneous disorders in which conflicting results in apoptosis and multidrug resistance (MDR) have been reported. We have evaluated by multiparameter flow cytometry the expression of apoptosis- (APO2.7, bcl-2, and bax) and MDR-related proteins [P-glycoprotein (P-gp), multidrug resistance protein (MRP), and lung resistance protein (LRP)] specifically on bone marrow (BM) CD34+ cells, and their major CD32-/dim and CD32+ subsets, in de novo AML (n=90), high-risk myelodysplastic syndrome (n=9), and low-risk myelodysplastic syndrome (n=21) patients at diagnosis, and compared with normal BM CD34+ cells (n=6). CD34+ myeloid cells from AML and high-risk myelodysplastic syndrome patients displayed higher expression of bcl-2 (P <0.0001) and lower reactivity for APO2.7 (P=0.002) compared with low-risk myelodysplastic syndrome and normal controls. Similar results applied to the two predefined CD34+ myeloid cell subsets. No significant differences were found in the expression of P-gp, MRP, and LRP between low-risk myelodysplastic syndrome patients and normal BM, but decreased expression of MRP (P <0.03) in AML and high-risk myelodysplastic syndromes and P-gp (P=0.008) in high-risk myelodysplastic syndromes were detected. Hierarchical clustering analysis showed that low-risk myelodysplastic syndrome patients were clustered next to normal BM samples, whereas high-risk myelodysplastic syndromes were clustered together and mixed with the de novo AML patients. In summary, increased resistance to chemotherapy of CD34+ cells from both AML and high-risk myelodysplastic syndromes would be explained more appropriately in terms of an increased antiapoptotic phenotype rather than a MDR phenotype. In low-risk myelodysplastic syndromes abnormally high apoptotic rates would be restricted to the CD34- cell compartments.  相似文献   
63.
Lack of apoptosis has been linked to prolonged survival of malignant B cells expressing bcl-2. The aim of the present study was to analyze the amount of bcl-2 protein expressed along normal human B-cell maturation and to establish the frequency of aberrant bcl-2 expression in B-cell malignancies. In normal bone marrow (n=11), bcl-2 expression obtained by quantitative multiparametric flow cytometry was highly variable: very low in both CD34(+) and CD34(-) B-cell precursors, high in mature B-lymphocytes and very high in plasma cells. Bcl-2 expression of mature B-lymphocytes from peripheral blood (n=10), spleen (n=8) and lymph node (n=5) was significantly higher (P<0.02) in CD23(-) as compared to CD23(+) B cells, independent of the type of tissue analyzed. Upon comparison with normal human B-cell maturation, bcl-2 expression in neoplastic B cells from 144 patients was found to be aberrant in 66% of the cases, usually corresponding to bcl-2 overexpression (63%). Follicular lymphoma (FL) carrying t(14;18) and MALT lymphoma were the only diagnostic groups constantly showing overexpression of bcl-2. Bcl-2 overexpression was also frequently found in precursor B-acute lymphoblastic leukemia (84%), typical (77%) and atypical (75%) B-cell chronic lymphocytic leukemia, prolymphocytic leukemia (two of three cases), mantle cell lymphoma (55%), but not in t(14;18)(-) FL, splenic marginal zone lymphoma, Burkitt lymphoma and multiple myeloma.  相似文献   
64.
直肠癌远侧癌旁黏膜p53基因突变及其蛋白表达   总被引:4,自引:0,他引:4  
目的 探讨直肠癌安全远侧切缘的合适长度。方法 分别采用PCR—SSCP和免疫组织化学方法,检测68例直肠癌远侧癌旁黏膜p53基因突变及p53蛋白表达情况。结果 26.47%(18/68)直肠癌远侧癌旁黏膜存在p53基因突变,突变范围均未超出肿瘤远侧3.0cm;23.53%(16/68)直肠癌远侧癌旁教膜存在p53蛋白表达,表达范围亦未超出肿瘤远侧3.0cm;直肠癌远侧癌旁黏膜p53基因突变及其蛋白表达与直肠癌临床病理学特征无相关性。结论 直肠肿瘤远侧3.0cm可能是直肠癌安全远侧切缘的合适长度。  相似文献   
65.
PURPOSE: We analyzed the successes and failures of SWL in the treatment of 2016 urinary calculi stratified according to size and position in the urinary tract. METHODS: All the patients were treated with a Modulith SL-20 (Storz Medical). RESULTS: The overall stone-free rate, regardless of the size and position of the stone, was 87.4%. The rate was different for kidney and ureteral stones. The stone-free rate observed for the different positions of the calculi within the kidney was upper calix 89.2%, middle calix 90.5% lower calix 84.8%, and renal pelvis 86.0%. For staghorn calculi, the stone-free rate was 60.0%. The stone-free rate for the different positions of calculi within the ureter was: upper ureter 84.3%, iliac ureter 82.4%, and pelvic ureter 91.0%. For calculi >24 mm, the retreatment rate increased, and the success rate dropped sharply. CONCLUSION: Extracorporal shockwave lithotripsy should be the first therapeutic option for urinary calculi of <24 mm regardless of their position in the urinary tract.  相似文献   
66.
The hypervariable regions of immunoglobulin heavy-chain (IgH) rearrangements provide a specific tumor marker in multiple myeloma (MM). Recently, real-time PCR assays have been developed in order to quantify the number of tumor cells after treatment. However, these strategies are hampered by the presence of somatic hypermutation (SH) in VDJH rearrangements from multiple myeloma (MM) patients, which causes mismatches between primers and/or probes and the target, leading to a nonaccurate quantification of tumor cells. Our group has recently described a 60% incidence of incomplete DJH rearrangements in MM patients, with no or very low rates of SH. In this study, we compare the efficiency of a real-time PCR approach for the analysis of both complete and incomplete IgH rearrangements in eight MM patients using only three JH consensus probes. We were able to design an allele-specific oligonucleotide for both the complete and incomplete rearrangement in all patients. DJH rearrangements fulfilled the criteria of effectiveness for real-time PCR in all samples (ie no unspecific amplification, detection of less than 10 tumor cells within 10(5) polyclonal background and correlation coefficients of standard curves higher than 0.98). By contrast, only three out of eight VDJH rearrangements fulfilled these criteria. Further analyses showed that the remaining five VDJH rearrangements carried three or more somatic mutations in the probe and primer sites, leading to a dramatic decrease in the melting temperature. These results support the use of incomplete DJH rearrangements instead of complete somatically mutated VDJH rearrangements for investigation of minimal residual disease in multiple myeloma.  相似文献   
67.
The aim of this animal study was to investigate the effects of intravitreal injection of indocyanine green (ICG) applied in macular hole surgery on retinal functional, morphology, and histologic changes. Eighteen (18) New Zealand albino rabbits were divided equally into three groups (6 rabbits in each). In Group A, both eyes of each rabbit were vitrectomized by perflouropropane gas compression. One (1) month later, 0.1 cc of different doses of ICG was injected into the vitreous in the left eyes. In the right eyes, 0.1 cc of balanced salt solution was injected intravitreally, allowing them to serve as control eyes. In Group B, the same doses of ICG were injected intravitreally. ICG was washed out by fluid-fluid exchange 3 minutes after injection. In Group C, the same doses of ICG were injected intravitreally in nonvitectomized eyes. Scotopic and photopic electroretinogram (ERG) recordings and indirect ophthalmoscopy examinations were performed to detect any functional and morphologic changes. Rabbit eyes were enucleated 4 months after ICG injections to observe histologic changes. Significant decreased of scotopic and photopic ERG amplitude and marked histologic changes were noted in eyes injected with 0.5 mg/cc and 0.1 mg/cc of ICG in nonvitrectomized eyes (Group C). In vitrectomized eyes (Group A), decreased scotopic and photopic ERGs and mild histologic changes were noted in eyes injected with 0.5 mg/cc, but no histologic changes were noted in eyes injected with 0.1 mg/cc. There was a transient, mild decrease in scotopic and photopic ERGs and no morphologic changes were noted in the eyes with fluid-fluid exchange (Group B). The toxicity of intravitreous ICG is dose- and time-dependent. ICG at 0.5 mg/cc, with short exposure time, is recommended in macular hole surgery.  相似文献   
68.
The binding parameters of 5-HT(2A) and levels of its second messenger, 1,4,5-trisphosphate (IP(3)), were simultaneously studied in frontal cortex and hippocampus from the brains of 18 control subjects and 18 depressed suicide victims. All suicides met DSM-III-R criteria for depressive symptoms, suffered a violent death and had not taken any antidepressant drugs for at least 6 months prior to death. A significant decrease in the number of 5-HT(2A) binding sites (154+/-22 vs. 254+/-36 fmol/mg), together with a significantly lower apparent affinity constant (1.02+/- 0.08 vs. 1. 36+/-0.09 nM), was detected in hippocampus but not in frontal cortex from the depressed suicides compared to the control subjects. Furthermore, IP(3) concentrations were significantly increased in hippocampus (3.2+/-0.3 vs. 2.1+/-0.3 pmol/g) but not in frontal cortex (1.3+/-0.3 vs. 2.7+/-0.5 pmol/g) from the suicide victims. The reported results may indicate a significant hypersensitivity of the 5-HT(2A) postsynaptic receptor located in the hippocampus from depressed suicide victims, giving rise to an enhancement of its intracellular signaling system with higher IP(3) production.  相似文献   
69.
目的:本研究在于分析低龄急性心肌梗死(AMI)患者血脂代谢异常的特点。方法:入选2001年10月-2004年12 月在我院收治的非糖尿病AMI患者230例,按年龄分组:年龄<55岁(I组),共78人;年龄≥55岁(Ⅱ组),共152人。测定血CHO、LDL-C、HDL-C、TG及CK、CK-MB峰值。结果:I组患者HDL-C[(34.8±7.61)mg/dL vs(40.0±13.6) mg/dL,P=0.032]水平明显低于Ⅱ组,有显著的统计学意义。TG水平却完全相反,I组明显高于Ⅱ组[(144.01±80.8) mg/dL vs(113.79±60.6)mg/dL,P=0.002],也有显著的统计学意义。LDL-C[(110.6±32.9)mg/dL vs(108.39± 32.13)mg/dL,P=0.597]和TC[(176.88±37.97)mg/dL vs(175.78±39.11)mg/dL,P=0.864]水平两组间没有显著性差异。讨论:所有入选的心肌梗死患者均为非糖尿病患者,其HDL-C均值都低于60mg/dL的水平,而且在I组中患者 HDL-C的水平较Ⅱ组更低,不到40mg/dL,同时与Ⅱ组相比TG水平偏高。非糖尿病急性心肌梗死患者血脂代谢紊乱在不同的年龄存在着不同的特点;年轻患者的血脂紊乱以低HDL-C和高甘油三酯为特点;分析原因考虑年轻患者与老龄患者生活方式的不同所致的饮食差异有关。结论:年轻非糖尿病AMI患者血脂代谢紊乱的特点与老年患者相比HDL- C更低而TG较高,两组LDL没有明显差异。  相似文献   
70.
乐胃饮干预功能性消化不良大鼠SP和VIP的研究   总被引:2,自引:2,他引:2  
[目的]通过实验研究,揭示乐胃饮治疗功能性消化不良的作用机制。[方法]Wistar大鼠随机分为正常对照组、自然恢复组、吗叮啉组、参苓白术丸组、乐胃饮低剂量组、乐胃饮中剂量组、乐胃饮高剂量组等7组,每组6只。分别给予各组按2ml/100g按组分别灌服蒸馏水、吗叮啉、参苓白术丸液、乐胃饮低中高剂量液,每天1次,自造模结束后一天起连续给药14天。观察胃黏膜形态,检测胃肠激素SP和VIP。[结果]乐胃饮能有效增加实验鼠胃窦组织中SP和降低VIP含量。[结论]乐胃饮能提高胃肠道神经兴奋性,调节胃肠道平滑肌的收缩,这可能是乐胃饮治疗FD的主要作用机制。  相似文献   
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