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991.
目的 探讨分化抑制蛋白-1(Inhibitor of differentiation-1,Id1)在套细胞淋巴瘤患者中的表达情况及其临床意义.方法 采用SP免疫组化法检测并分析45例套细胞淋巴瘤和20例淋巴结反应性增生淋巴结组织中Id1表达水平,以及Id1的表达与其临床预后指标的关系.结果 Id1在套细胞淋巴瘤和淋巴结反应性增生淋巴结组织中阴性、弱阳性和强阳性的表达率分别是15.56%,31.11%,53.33%和65.00%,25.00%,10.00%(P<0.05).套细胞淋巴瘤组织中Id1阳性表达与患者LDH、临床分期、结外累及部位和近期疗效有关(P均<0.05);年龄、性别、WBC计数、PLT计数、HB含量无相关(P均>0.05).经过Log-rank检验显示,Id1低表达组和Id1高表达组的1年生存率分别是90.48%和79.17% (P >0.05);3年生存率分别是66.67%和33.33%(P<0.05);5年生存率分别是47.62%和16.67% (P <0.05),Kaplan-Meier生存分析显示Id1高表达组3年、5年生存率低于Id1低表达组(P<0.05).结论 Id1在套细胞淋巴瘤淋巴结中呈高表达,并与部分预后相关指标有关,Id1高表达组表现出低生存率,Id1可能成为套细胞淋巴瘤预后不良的评价指标.  相似文献   
992.
993.
目的:测定冷藏(4℃)保存48 h后血小板膜糖蛋白GPⅠbα末端糖基脱落情况。方法分别以一定浓度梯度的FITC-sWGA、FITC-RCA-1、FITC-ECA标记血小板,应用流式细胞仪检测,确定最佳工作浓度。检测冷藏保存48 h后血小板GPⅠbα末端唾液酸基及次末端半乳糖基脱落情况。结果 FITC-sWGA、FITC-RCA-1、FITC-ECA工作浓度分别为2μg/ml、2μg/ml、30μg/ml时标记效果好。冷藏保存48 h后GPⅠbα末端唾液酸基及次末端半乳糖基脱落较22℃常规保存明显增加,分别增至(156±18)%及(123±13)%,差异有统计学意义(P<0.01)。结论冷藏保存48 h可致血小板膜糖蛋白GPⅠbα末端糖基脱落增加。  相似文献   
994.

Background:

Plantar pressure serves as a key factor for predicting ulceration in the feet of diabetes patients. We designed this study to analyze plantar pressure changes and correlating risk factors in Chinese patients with type 2 diabetes.

Methods:

We recruited 65 patients with type 2 diabetes. They were invited to participate in the second wave 2 years later. The patients completed identical examinations at the baseline point and 2 years later. We obtained maximum force, maximum pressure, impulse, pressure-time integral, and loading rate values from 10 foot regions. We collected data on six history-based variables, six anthropometric variables, and four metabolic variables of the patients.

Results:

Over the course of the study, significant plantar pressure increases in some forefoot portions were identified (P < 0.05), especially in the second to forth metatarsal heads. Decreases in heel impulse and pressure-time integral levels were also found (P < 0.05). Plantar pressure parameters increased with body mass index (BMI) levels. Hemoglobin A1c (HbA1c) changes were positively correlated with maximum force (β = 0.364, P = 0.001) and maximum pressure (β = 0.366, P = 0.002) changes in the first metatarsal head. Cholesterol changes were positively correlated with impulse changes in the lateral portion of the heel (β = 0.179, P = 0.072) and pressure-time integral changes in the second metatarsal head (β = 0.236, P = 0.020). Ankle-brachial index (ABI) changes were positively correlated with maximum force changes in the first metatarsal head (β = 0.137, P = 0.048). Neuropathy symptom score (NSS) and common peroneal nerve sensory nerve conduction velocity (SCV) changes were positively correlated with some plantar pressure changes. In addition, plantar pressure changes had a correlation with the appearance of infections, blisters (β = 0.244, P = 0.014), and calluses over the course of the study.

Conclusions:

We should pay attention to the BMI, HbA1c, cholesterol, ABI, SCV, and NSS changes in the process of preventing high plantar pressure and ulceration. Some associated precautions may be taken with the appearance of infections, blisters, and calluses.  相似文献   
995.
996.
目的探讨G蛋白偶联受体激酶4(G protein-coupled receptor kinase 4,GRK4)对内皮素B型受体(endothelin receptor B,ETB)的异常调节在原发性高血压中的作用及机制。方法选用12~14周龄,体质量300 g左右的雄性自发性高血压大鼠(spontaneously hypertensive rats,SHRs)及其对照鼠(Wistar-Kyoto,WKY)各10只,通过无创鼠尾测压仪测定血压,采用右肾上腺静脉插管灌注ETB受体特异性激动剂BQ3020后观察尿流速及尿钠排泄率,荧光定量PCR检测大鼠肾脏GRK4 mRNA水平,Western blot测定大鼠肾脏GRK4及ETB受体的蛋白表达差异,免疫共沉淀法检测ETB受体磷酸化情况,在动物水平观察高血压状态下ETB受体的功能情况。结果 ETB受体激动剂BQ3020对WKY大鼠有明显利尿排钠作用,且这种利尿排钠作用可以被ETB受体抑制剂BQ788阻断,但在SHR大鼠BQ3020的利尿排钠作用受损[尿流速:(11.23±2.16)vs(3.49±1.32),P<0.05];尿钠排泄率:[(1 551.43±393.47)vs(601.16±128.15),P<0.05];在SHR大鼠肾皮质GRK4的蛋白水平及mRNA水平均较WKY大鼠高[蛋白:(1.38±0.10)vs(0.85±0.07),P<0.05];mRNA:[(2.23±0.15)vs(0.78±0.16),P<0.05],SHR大鼠ETB受体总蛋白水平与WKY大鼠相比差异无统计学意义(P>0.05),但ETB受体磷酸化水平增高。结论 GRK4可能通过对内皮素B型受体的异常调节,参与了原发性高血压发生与发病。  相似文献   
997.
Inhalers containing corticosteroids and long-acting beta2-agonists are becoming increasingly important in asthma management. A rapid effect is important to patients, particularly during exacerbations. We compared the onset of bronchodilation and patient-perceived relief from dyspnoea following single-inhaler budesonide/formoterol or salmeterol/fluticasone in a model of acute bronchoconstriction. A randomised, double-blind, double-dummy, single-dose, crossover study included 27 outpatients with asthma (mean age 35 years; mean FEV1 90% predicted normal). Immediately following methacholine-induced bronchoconstriction (fall in FEV1 > or = 30%), patients inhaled budesonide/formoterol (160/4.5 microg, 1 or 2 inhalations; Symbicort Turbuhaler), salmeterol/fluticasone (50/250 microg; Seretide Diskus) or placebo on 4 study days. Lung function and Borg score were assessed for 30 min. During methacholine-induced provocation (final mean FEV1 62.5% of baseline), mean Borg score increased 10-fold (from 0.3 to 3.0 units). Hereafter, mean FEV1 at 3 min improved significantly more after budesonide/formoterol 1 and 2 inhalations (37 and 38%, respectively) than after salmeterol/fluticasone (23%; P < 0.001) or placebo (10%; P < 0.001). Median recovery times to 85% of baseline FEV1 were shorter for budesonide/formoterol (1 or 2 inhalations: 3.3 and 2.8 min, respectively) than salmeterol/fluticasone (8.9 min; P < 0.001) and placebo (> 30 min). One min after budesonide/formoterol, dyspnoea was significantly reduced (Borg score -0.86 units, both doses) compared with salmeterol/fluticasone (-0.55 units; P < 0.05) and placebo (-0.23 units; P < 0.001). Budesonide/formoterol provides immediate bronchodilation, faster than salmeterol/fluticasone, which patients can feel during acute methacholine-induced bronchoconstriction.  相似文献   
998.
999.
OBJECTIVES: We sought to determine whether intrinsic mitochondrial function and regulation were altered in heart transplant recipients (HTRs) and to investigate the response of mitochondrial function to six-week endurance training in these patients. BACKGROUND: Despite the normalization of central oxygen transport during exercise, HTRs are still characterized by limited exercise capacity, which is thought to result from skeletal muscle metabolic abnormalities. METHODS: Twenty HTRS agreed to have vastus lateralis biopsies and exercise testing: before and after training for 12 of them and before and after the same control period for eight subjects unwilling to train. Mitochondrial respiration was evaluated on saponin-permeabilized muscle fibers in the absence or presence (maximum respiration rate [V(max)]) of saturating adenosine diphosphate. RESULTS: Mitochondrial function was preserved at the level of sedentary subjects in untrained HTRs, although they showed 28 +/- 5% functional aerobic impairment (FAI). After training, V(max), citrate synthase, cytochrome c oxidase, and mitochondrial creatine kinase (CK) activities were significantly increased by 48%, 40%, 67%, and 53%, respectively (p < 0.05), whereas FAI decreased to 12 +/- 5% (p < 0.01). The control of mitochondrial respiration by creatine and mitochondrial CK was also improved (p < 0.01), suggesting that phosphocreatine synthesis and transfer by the mitochondrial CK become coupled to oxidative phosphorylation, as shown in trained, healthy subjects. CONCLUSIONS: In HTRs, the mitochondrial properties of skeletal muscle were preserved and responded well to training, reaching values of physically active, healthy subjects. This suggests that, in HTRs, immunosuppressive drugs do not alter the intrinsic muscle oxidative capacities and that the patients' physical handicap results from nonmitochondrial mechanisms.  相似文献   
1000.
The major drug of abuse among teenagers in the United States continues to be ethanol (EtOH), but use is seen in children as young as nine. In the studies reported here, the impact of EtOH on biologic and hormonal parameters of puberty was assessed in female rats. Rats were fed a liquid diet containing EtOH, pair fed an identical liquid diet containing dextrimaltose instead of EtOH, or fed a liquid diet not containing EtOH ad libitum. Feeding was started at 21, 25, or 28 d of age. EtOH markedly delayed the age at vaginal opening (34.5±0.5 d in controls vs 48.5±2.4 d in EtOH animals; p<0.001), delayed the age at first estrous (40.9±0.6 d in controls vs 61.2±2.6 d in EtOH animals; p<0.001), increased the length of the estrous cycle, and decreased the number of proestrous days. EtOH, concomitant with reduced ovarian and uterine weight, decreased serum estradiol and progesterone. Associated with these changes in ovarian hormones there was a selective increase in follicle-stimulating hormone, but not luteinizing hormone. EtOH consistently reduced insulin-like growth factor-1. In general, EtOH-induced disruption was more severe the younger the animals were at the start of feeding. Opiate receptor blockade with naltrexone completely prevented the EtOH-induced delay in vaginal opening. The impact of EtOH on female puberty is dramatic, is an emerging public health problem, and deserves more study.  相似文献   
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