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11.
Ten patients with DSM-III-R obsessive-compulsive disorder (OCD) underwent the desipramine (DMI) growth hormone (GH) stimulation test as well as the dexamethasone suppression test (DST). The results were compared with the responses in a group of matched healthy controls. The GH response to DMI did not differ between patients and controls and 9 of 10 patients showed cortisol suppression in response to dexamethasone. The data suggest that neither alpha 2 adrenergic dysfunction nor DST non-suppression are features of primary OCD.  相似文献   
12.
大剂量地塞米松及SOD在实验性脑损伤中的治疗作用   总被引:1,自引:0,他引:1  
大剂量地塞米松和SOD是外伤性脑继发性损害药物治疗的新方案。本实验在豚鼠局灶性脑损伤模型上试用该两种药物,通过脑含水量、灶周伊文斯兰渗出、血CK、Ca和LDH含室及光镜和电镜病理检查等指标。  相似文献   
13.
目的探讨体外循环不同途径给予鱼精蛋白所产生的不良反应及地塞米松对这些不良反应的预防作用。方法将 6 4例患者按给药途径及是否预防性给予地塞米松分为 4组 :A1,A2 ,B1和B2 组。A组升主动脉给药 ,B组颈内静脉给药 ;A1,B1组给予地塞米松 ,A2 ,B2 组不给予地塞米松。观察各组注射鱼精蛋白后 3,10 ,2 0 ,30min平均动脉压 (meanarterialpressure ,MAP)、平均肺动脉压 (meanpulmonaryarterialpressure ,MPAP)及气道压力(airwaypressure ,AP)的变化。结果A1组各时间点数据无显著性差异 (P >0 .0 5 ) ,A2 组给予鱼精蛋白 3min后血压下降 (P <0 .0 5 ) ;B1组给予鱼精蛋白 3min后血压下降 (P <0 .0 5 ) ,气道压力升高 (P <0 .0 5 ) ,B2 组给予鱼精蛋白 3,10 ,2 0min后血压明显下降 (P <0 .0 5 ,P <0 .0 1) ,气道压力升高 (P <0 .0 5 ,P <0 .0 1)。结论从主动脉根部注射鱼精蛋白对血流动力学影响较静脉给药小 ,地塞米松对鱼精蛋白的副作用有一定的预防作用  相似文献   
14.
阿昔洛韦对单纯疱疹病毒脑炎小鼠脑细胞的保护作用   总被引:1,自引:0,他引:1  
目的 了解单纯疱疹病毒脑炎(HSE)脑细胞结构的改变及药物的影响。方法 采用光学显微镜及透射电子显微镜观察HSE小鼠脑细胞结构的变化,并给予阿昔洛韦(ACV)及地塞米松(DEX)治疗,观察治疗后脑细胞结构的变化。结果 HSE小鼠脑神经细胞明显肿胀,核仁固缩,核内结构破坏,线粒体及高尔基体可见空泡样变性,核仁内可见病毒颗粒。用药物干预的小鼠脑神经细胞改变较轻微,未找到病毒颗粒;与单用ACV干预的小鼠相比,用ACV DEX干预的小鼠脑神经细胞及毛细血管周围水肿明显减轻。结论 HSE早期给予ACV DEX治疗,对HSE脑细胞结构有明显保护作用。  相似文献   
15.
In the past few years there have been numerous publications which have stressed the value of the dexamethasone suppression test (DST) as a diagnostic marker of endogenous depression. Our own studies in 333 psychiatric inpatients and 121 healthy subjects did not reveal a differential diagnostic use for the DST. This result is in good agreement with other results in the literature. Our data demonstrate that intervening variables such as severity of illness, weight loss, sleep disturbances, situational stress, drug and alcohol withdrawal, and the pharmacokinetics of dexamethasone have an important influence on DST results, regardless of the diagnostic classification.  相似文献   
16.
To determine if dexamethasone has a role in the treatment of meningeal leukemia, 8 consecutive patients with acute lymphoblastic and signs or symptoms of CNS were included in the study. After the confirmation of leukemic blast cells on cerebrospinal fluid, they received intrathecal and IV dexamethasone; 3 days later the patients received “triple” intrathecal chemotherapy with dexamethasone, methotrexate and cytarabine, and the spinal fluid was studied again. All patients had good clinical response and 7 out of the 8 patients showed reduction on the CSF cell count after the use of dexamethasone alone. The results suggest that dexamethasone is a lympholytic agent that could play a more active role in the prevention and therapy of meningeal leukemia and should be preferred over hydrocortisone in the so called “triple” intrathecal chemotherapy for the prevention and treatment of CNS leukemia. © 1995 Wiley-Liss, Inc.  相似文献   
17.
胸腺免疫抑制组分的抗变态反应作用   总被引:1,自引:0,他引:1  
整体实验表明,胸腺免疫抑制组分肌内注射1wk对大鼠被动皮肤过敏反应(8、20、50和125mg·kg-1)兔Arthus反应(4和12mg·kg-1)均有明显的抑制作用。体外实验表明,该药能抑制致敏豚鼠离体回肠平滑肌的过敏性收缩,IC50为446.7mg·L-1。上述结果表明,胸腺免疫抑制组分有抗Ⅰ和Ⅲ型变态反应的作用。  相似文献   
18.
To evaluate the catabolic effects of dexamethasone therapy on protein metabolism, amino acid concentrations and urinary 3-methylhistidine (3MH) were measured in 28 premature infants who were included in a double-blind controlled study using early dexamethasone therapy in the prevention of bronchopulmonary dysplasia. Fifteen infants received dexamethasone (0.5mg/kg/day i.v.) and 13 infants received normal saline as control. Heparinized venous blood samples for amino acid analysis were obtained before the study and again at day 5 after starting the study. Urinary 3MH was measured on days 1, 3, 5, 7, 14, 21, and 28 of treatment. A substantial increase in amino acid concentrations was observed in infants receiving dexamethasone. Alanine, glutamine, citrulline, ornithine and cystine concentrations increased twofold or more. The 3MH:creatinine ratio was increased in the treated group. These metabolic effects were most likely due to an increase in protein catabolism.  相似文献   
19.
Gene expression profiling using microarrays (rat-specific array RG-U34A, Affymetrix, U.S.A.) was employed for the investigation of: (1) hormonal regulation of renal function and (2) nephrotoxicity. For this purpose about 8,800 genes were analysed in kidney and, additionally, in liver tissue.

Ad 1.) Kidney functions develop during postnatal life. Thus, in vivo transport and accumulation of p-aminohippurate (PAH) was investigated on renal cortical slices (RCS) from 10- and 55-day-old rats. The animals were treated with dexamethasone (DEXA; 60 μg/100 g b.wt./day) for 3 days, which caused a significant reduction in the accumulation of PAH in 10-day-old rats (42 ± 5% whereas it was only slightly reduced in 55-day-old rats (70 ± 8%). To further clarify the regulation of renal function by DEXA, results were compared with those obtained previously after in vitro stimulation with DEXA. RCS were incubated for 24 hours in DEXA-containing medium (10−9 M). Under these conditions DEXA significantly increased the PAH uptake capacity in RCS obtained from 10- and 55-day-old rats up to 126 and 136%, respectively. Thus a stimulation of tubular transport capacity is possible in vitro. The effect of DEXA treatment on the gene expression of the kidney (in vivo) was moderate. Focussing especially on transporters, ion channels, ATPases, glucuronyltransferases, glutathione-S-transferase and cytochrome P450, the expression of only few genes were significantly changed (3 to 50-fold up- or down-regulation). Moreover, distinct age differences were found after in vivo administration of DEXA. The investigation of in vitro effects of DEXA is currently been performed.

Ad 2.) The kidney is threatened by nephrotoxins because of its ability to accumulate them. We used a single administration of uranyl nitrate (UN; 0.5 mg/100 g b.wt.) as a model for chronic renal failure (CRF). Clearance experiments were performed 10 weeks after UN administration (maximal symptoms of CRF) in adult female rats. As expected, UN induced interstitial cicatrices with reduced GFR and diminished PAH transport capacity. Despite the impressive morphological and functional changes in the kidney after exposure to UN, the gene expression profiles in the kidneys were only minimally affected: we found significantly changed expression levels for only 20 genes (5 genes were up-regulated [e.g. transgelin], 15 down-regulated [among these the Na-K-Cl-symporter, insulin-like growth factor, kallikrein, and ornithine decarboxylase). The lack of agreement between gene expression data and the nephrotoxic effects of UN can probably be explained by the long time interval between dosing and the assessment of the effect. The results confirm that primary genomic responses are likely to be strongest transiently after exposure and then decrease in intensity.  相似文献   

20.
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