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41.
28例经手术或脑穿刺病理证实的脑脓肿病例,均行CT平扫和增强检查,其中23例行MRI检查。其CT与MRI表现为:单发24例,多发4例。CT平扫示各个时期的脑脓肿表现不完全相同,典型病灶主要表现为低密度囊性病灶或等低混杂密度的囊实性病灶(20~42Hu),其中2例病灶内含气体,增强后病灶中央无强化。周围有明显强化的壁,除6例囊壁欠光整外,其余病灶囊壁较光整。MRI平扫示病灶中央呈低T1WI、高T2WI信号灶,有环形的高信号的壁,增强后壁强化明显,病灶中央无强化。认为脑脓肿CT与MRI表现有一定特征性,CT、MRI对脑脓肿有极高的诊断价值。  相似文献   
42.
肾宁口服液对兔膜性肾病模型肾保护作用的实验研究   总被引:1,自引:0,他引:1  
目的观察肾宁口服液治疗膜性肾病的实验研究.方法用阳离子牛血清白蛋白(C-BSA)制备家免膜性肾病模型,设立正常对照组、中药治疗组、激素治疗组和模型组.每周测定一次24h尿蛋白,实验结束时测定血浆白蛋白、血脂和肾功能等生化指标.结果肾宁口服液中药治疗组的24h尿蛋白、血脂和肾功能等生化指标较模型组明显改善(P<0.01或P<0.05),而激素治疗组与模型组比较无明显差异(P>0.05).结论肾宁口服液能降低尿蛋白,提高血浆白蛋白,改善肾功能,对膜性肾病有显著疗效.  相似文献   
43.
BACKGROUND: Sevelamer hydrochloride was recently proposed as a phosphate binder to prevent hypercalcaemia in place of calcium alkaline salts in dialysis patients. So far, it has been evaluated only in patients receiving calcitriol, without comparison with CaCO(3) alone, although the latter was found to be as effective as the combination of calcitriol and Al(OH)(3) in suppressing parathyroid hormone (PTH) without inducing hypercalcaemia and to have a better lowering effect on serum phosphate. Moreover, this bile salt binder may decrease serum 25-OH vitamin D. Therefore, we compared for 5 months two strategies for controlling moderate hyperparathyroidism: CaCO(3) alone vs sevelamer in conjunction with measures to increase calcium balance. METHODS: Forty-two patients were randomized: 21 continued their treatment with 4.8 g/day CaCO(3) and 21 were switched to sevelamer (initial dose: 2.4 g/day, increased to 4.4 g/day). Each month, when serum-corrected calcium decreased below 2.30 mmol/l, dialysate calcium was increased or alphacalcidol was given at each dialysis session, according to serum PO(4) levels. The following parameters were monitored: serum Ca, PO(4), bicarbonate and protein, weekly; and serum PTH, 25-OH vitamin D and total, LDL and HDL cholesterol monthly. RESULTS: Except for higher serum phosphate at month 1, lower serum bicarbonate at month 2 and lower LDL cholesterol at month 5 in the sevelamer group, no difference was found between the two groups. Compared with baseline levels, PTH increased and 25-OH vitamin D decreased significantly in both groups, these two parameters being inversely correlated. CONCLUSIONS: Given comparable control of plasma calcium, phosphate and 25-OH vitamin D, PTH control is comparable in both strategies. Sevelamer does not induce greater vitamin D depletion than CaCO(3). The transient decrease of serum bicarbonate after discontinuation of CaCO(3) in the sevelamer group suggests a less optimal prevention of acidosis. The sevelamer-induced decrease in LDL cholesterol gives this drug a potential advantage in cardiovascular prevention.  相似文献   
44.
乙型肝炎患者可溶性白细胞介素2受体水平变化   总被引:5,自引:0,他引:5  
本研究应用酶联免疫吸附试验(ELISA)检测了103例乙型肝炎各型患者及26倒乙肝病毒(HBV)携带者血清中可溶性白细胞介素2受体(sIL-2R)水平,并结合临床资料进行分析。结果发现:各型患者及HBV 携带者sIL-2R 水平均明显高于正常对照(P<0.01~0.001),其升高程度与病情轻重呈正比,在去除危重患者酶—胆分离时谷丙转氨酶(ALT)过低的影响后,sIL-2R 水平与ALT 有良好的正相关关系(r=0.38.p<0.05);作者认为sIL-2R 能够较好地反映疾病的活动状况,动态观察血清sIL-2R 水平的变化,对判断和评价HBV 感染后的病情演变及免疫失衡状态具有重要意义。  相似文献   
45.
[目的] 研究三七总皂苷眼用凝胶在兔眼组织的药物分布。[方法] 选取12只新西兰大白兔,随机分为4组,每组3只兔子。每只兔眼分别给予凝胶41.67 μL/kg(即三七皂苷R1 0.132 mg/kg,人参皂苷Rg1 0.452 mg/kg)。给药后于0.5、1、1.5、2 h空气栓塞各处死1组兔子。取眼球,分离各眼组织。采用UPLC-MS检测不同时间点各眼组织的药物含量。[结果] 兔眼给予三七总皂苷眼用凝胶后,三七皂苷R1在兔角膜、晶状体、房水、玻璃体中的最大含量分别为13.16、1.16、0.86、0.10 μg/g,人参皂苷Rg1在角膜、晶状体、房水、玻璃体中的最大含量分别为38.49、4.50、3.38、0.28 μg/g。[结论] 三七总皂苷眼用凝胶滴到兔眼后,三七皂苷R1和人参皂苷Rg1可透过角膜分散到各眼组织。在0~2 h内,各眼组织中的药物含量由高到低依次为角膜、晶状体、房水、玻璃体,表明三七皂苷R1和人参皂苷Rg1可透过角膜,到达眼后部组织,在2 h时各眼部组织的药物含量依然较高,在眼组织的保留时间长。  相似文献   
46.
47.
IL-18 Receptor Expression on Epithelial Cells is Upregulated by TNF Alpha   总被引:1,自引:0,他引:1  
IL-18 is a multifunctional cytokine that augments both innate and acquired immunity and potentiates Th1 and Th2 reactions. We studied the expression of IL-18 receptor (IL-18R) on renal and respiratory epithelial cell lines. Both cell lines upregulated IL-18R mRNA and IL-18R membrane expression in response to TNF alpha and other proinflammatory cytokines. The function of IL-18R was confirmed by induction of IL-8 release from epithelial cells in response to recombinant IL-18. Epithelial cells may represent an important target for IL-18, mainly under inflammatory conditions associated with TNF alpha release.  相似文献   
48.
We have established hybridoma lines which secrete mouse monoclonal antibodies (Mabs) to human pituitary growth hormone, hGH. Using indirect competitive ELISA and indirect passive hemagglutination inhibition twelve different Mabs were characterized with regard to cross-reactivity with the hGH-related hormones, human chorionic somatomammotropin, hCS, and human prolactin, hPRL. The reactivity of these Mabs with pituitary hGH was compared to that with either bacterially-produced methionyl-hGH or to that of reduced and S-carboxymethylated hGH, which has an altered conformation. None of the Mabs reacted with hPRL. Four did not react with hCS whereas the others showed varying degree of cross-reactivity with hCS. All Mabs reacted more weakly with reduced and S-carboxymethylated hGH than with the native form of the hormone, which was not seen with conventional rabbit antisera to hGH. Thus in the case of hGH the Mabs are superior to conventional antisera in revealing small conformational differences. However the pituitary and bacterially-derived methionyl-hGH were indistinguishable as determined by the 12 Mabs.  相似文献   
49.
It has been suggested for many years that the regulation of the immune system for the maintenance of peripheral tolerance may involve regulatory/suppressor T cells. In the past few years, several investigators have demonstrated that these cells can be generated in vitro. It has also been shown that they can inhibit the progression of various autoimmune disease models when infused into susceptible mice. We have generated two murine T cell lines in the presence of KLH-specific T cell clones from BALB/c or DBA2 mice. The lines are characterized by a low proliferative response to mitogens, the capacity to secrete high amounts of IL-10 and TGF-beta, and small amounts of IFN-gamma. Interestingly, these cells are unable to produce IL-2, IL-4 or IL-5. The study of the surface phenotype of both lines revealed CD4+, CD25high, CD44low and CTLA-4- cells. When injected intravenously in (CBy.D2) F1 mice, these cells were able to inhibit 50-100% of the TNP-specific antibody production, when the hapten was coupled to KLH. In the present study we offer another evidence for the existence of regulatory T cells in the T lymphocyte repertoire, suggesting that they can also regulate immune responses to foreign antigens. Furthermore, we demonstrate an alternative pathway to generate these cells different from approaches used thus far.  相似文献   
50.
Robert D.  Hare  Daniel  Craigen 《Psychophysiology》1974,11(2):197-206
Heart rate (HR) and skin conductance (SC) were recorded while 17 psychopathic (P) and 17 nonpsychopathic (NP) inmates (referred to as A) were engaged in a mixed-motive game situation with another S (referred to as B). On each trial A had to choose the intensity of shock to be delivered to himself and to B. B then was given a chance to retaliate, although his choices were actually overridden by the experimenter. A 10 sec tone (CS) preceded delivery of shock to each S. There were no differences between Groups P and NP in the intensity of shock chosen for themselves and for the other (B) Ss. Compared with Group NP, Group P gave small unconditioned skin conductance (SC) responses to shock directly received and to shocks delivered to the other S. There were no differences between groups in the unconditioned HR response to either direct shock (acceleration) or to shocks delivered to the other S (slight deceleration). Group P gave small electrodermal orienting responses (ORs) and anticipatory responses (ARs) to the CS preceding shock to self and shock to other; Group NP gave relatively large ORs and ARs to the CS preceding shock to self, and small ones prior to shock to other. Both Groups gave a biphasic conditioned HR response–acceleration followed by deceleration; each component was larger in Group P than in Group NP, and the acceleratory component in Group P appeared on the first trial. The electrodermal data were consistent with the view that psychopaths experience little fear arousal prior to reception of aversive stimuli by themselves or by others. It was suggested that the anticipatory HR responses of the psychopathic Ss were part of an adaptive response that helped them to cope with stress.  相似文献   
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