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101.
The haemodynamic response to the insertion of the laryngeal mask airway: a comparison with laryngoscopy and tracheal intubation 总被引:3,自引:0,他引:3
The haemodynamic response to the insertion of the laryngeal mask airway (LMA) was assessed and compared to that of laryngoscopy and tracheal intubation in a study of forty patients (ASA 1) randomly allocated into two groups and anaesthetised using a standard balanced anaesthetic technique. The results show that the changes in all cardiovascular parameters measured following LMA insertion were significantly less (P<0.05) when compared with those following laryngoscopy and tracheal intubation. We conclude that airway management with the LMA may be used to avoid the haemodynamic response to tracheal intubation where such a response is undersirable. 相似文献
102.
在排除电场干扰伪迹后,耳蜗微音电位响应曲线可以作为反映近全耳蜗电生理功能的一项测试指标。能方便而迅速地完成测试,结果可靠。船舶噪声暴露后,显示耳蜗损伤频带主要在3.15~8kHz范围。这与人噪声性听力损失的特征非常类似。 相似文献
103.
作者于1991年7~9月,对波纹龙虱捕食淡色库蚊幼虫功能反应进行了研究。结果表明。在实验室条件下,波纹龙虱的捕食量随着蚊幼密度的增加而增大,其曲线符合Holling Ⅱ型功能反应,即其捕食量与猎物密度呈负加速曲线型。并根据Holling圆盘方程,建立了波纹龙虱捕食功能反应数学模型。波纹龙虱的寻找效应随着猜物密度的增加而降低。 相似文献
104.
Shuu-Jiun Wang Kwong-Kum Liao Hung-Hsiang Liou Shei-Shee Lee Ching-Piao Tsai Kon-Ping Lin Ko-Pei Kao Zin-An Wu 《Muscle & nerve》1994,17(4):411-418
Sympathetic skin response (SSR) and R–R interval variation (RRIV) were studied in 36 chronic, nondiabetic uremics to compare with their nerve conduction studies (NCS) and clinical dysautonomia. Abnormal SSR was noted in 5 (13.9%) patients, abnormal RRIV in 14 (38.9%), and abnormal NCS in 26 (72.2%). The patients were classified into three groups: group (GP) 1: “normal,” n = 21 (58.3%), normal RRIV and SSR; GP 2: “isolated parasympathetic dysfunction,” n = 10 (27.8%), abnormal RRIV and normal SSR; and GP 3: “sympathetic sudomotor dysfunction,” n = 5 (13.9%), abnormal SSR. A significant difference in age was found among the three groups (GP 3 > GP 2 > GP 1; P < 0.0001, ANOVA). After controlling the age factor, we still noted a tendency toward increasing NCS disturbances (distal latency and nerve conduction velocity of peroneal nerve; P < 0.05, multiple regression analysis) and frequencies of clinical autonomic symptoms (postural dizziness and impotence; P < 0.05, Mantel–Hanszel test) from GP 1 to GP 3. Patients with abnormal SSR (GP 3) displayed significantly higher frequencies of postural dizziness and impotence, indicating the relationship between an absence of SSR and clinical dysautonomia. © 1994 John Wiley & Sons, Inc. 相似文献
105.
Albano C.; Smitz J.; Camus M.; Riethmuller-Winzen H.; Siebert-Weigel M.; Diedrich K.; Van Steirteghem A.C.; Devroey P. 《Human reproduction (Oxford, England)》1996,11(10):2114-2118
A third-generation gonadotrophin-releasing hormone antagonist(Cetrorelix) was used during ovarian stimulation in 32 patientsundergoing assisted reproduction, in order to prevent the prematureluteinizing hormone (LH) surge. In all patients, ovarian stimulationwas carried out with two or three ampoules of human menopausalgonadotrophin (HMG), starting on day 2 of the menstrual cycle.In addition, 0.5 mg of Cetrorelix was administered daily fromday 6 of HMG treatment until the day of ovulation inductionby human chorionic gonadotrophin (HCG). A significant drop inplasma LH concentration was observed within a few hours of thefirst administration of Cetrorelix (P<0.005). Moreover, noLH surge was detected at any point in the treatment period inany of the 32 patients. A mean oestradiol concentration of 2122±935ng/1 was observed on the day of the HCG administration, indicatingnormal folliculogenesis. Like LH, progesterone concentrationalso dropped within a few hours of the first administrationof Cetrorelix (P< 0.005). A 0.5 mg daily dose of Cetrorelixprevented a premature LH surge in all the 32 patients treated. 相似文献
106.
107.
胆红素对新生豚鼠蜗核损伤的动态研究 总被引:2,自引:0,他引:2
目的 探讨听性脑干反应 (ABR)在胆红素所致听力损伤中的监测价值。方法 2 0只新生 5日豚鼠随机分为胆红素组和对照组 ,胆红素组腹腔注射胆红素 (2 0 0 μg/ g) ,对照组腹腔注射相应体积的生理盐水 (0 1ml/g) ,于腹腔注射前和后 4h、 8h分别记录ABR并观察神经行为状况 ,每组各取 5只于腹腔注射后 4h、 8h分别行蜗核形态学观察。结果 注射胆红素后 ,ABR波潜伏期、波间期呈逐渐延长趋势 ,振幅呈逐渐下降趋势 ,其中波Ⅱ改变出现最早且最明显。用药后 4h ,无明显神经系统症状和形态学改变时 ,Ⅰ -Ⅱ波间期延长及波Ⅱ振幅下降与对照组及用药前比较差异有显著性 (P <0 0 1) ;用药后 8hABR改变更明显 ,同时伴有神经症状和镜下形态学改变 ,蜗核体积及大椭圆细胞截面积显著性减小 (P <0 0 1)。结论 ABR是监测胆红素所致听力损害早期的敏感指标 ,优于耳蜗电图和耳声发射等主要反映周围听觉系统功能状态的电生理技术 ,加强高胆红素血症新生儿的ABR动态监测有非常重要的临床意义 相似文献
108.
Eduardo M. B. Tinoco Ståle P. Lyngstadaas Hans R. Preus Per Gjermo 《Journal of clinical periodontology》1997,24(12):937-944
Abstract Immunological data have been suggested to be a potential tool in the diagnosis, classification and monitoring of periodontal diseases. However, the role of circulating antibodies in periodontal patients is poorly understood. Patients suffering from localized juvenile periodontitis (LJP) are often reported to show high titers of serum IgG antibodies against Aetinobaeillus actinomycetemcomitans (A. actinomycetemcotnitans), but several affected patients do not. Most studies use well-known reference strains of the bacterium for testing against the patients' sera. The aim of the present investigation was to study the relationship between serum IgG antibody levels to autologous A. actinomycetemcomitans strains and clinical attachment loss (CAL). In addition, we wanted to assess the patients’serum titers against 4 well-known reference strains of the bacterium as well as their general potential immunoglobulin response. Intravenous blood samples were taken from 23 LJP patients and 10 healthy individuals, and autologous A. actinomycetemcomitans strains were cultured from 18 of the L.JP patients. CAL was measured at 4 different sites around ail present teeth and assessed as a % of teeth with at least 1 site moderately ≥2<5 mm) or severely (≥5 mm) involved. An enzyme-linked immunosorbent assay (ELISA) was performed to evaluate the serum titers of IgG antibodies to A. actinomycetemcomitans antigens. No significant correlation was found between serum IgG antibody titers to autologous strains and CAL. However, there was a trend that low responders had more moderately affected teeth than had high responders and patients with undetectable A. actinomycetemcomitans levels, which is in agreement with a hypothetically protective role of the antibodies. The total counts of immunoglobulin assessed in all participants showed that the predominant class was IgG and the reference group displayed significantly less (p<0.05) IgG and IgG1 counts than the LJP patients. Both the reaction pattern against reference and autologous strains varied widely. We conclude that the specific antibody response against A. actinomycetemcomitans shows a weak correlation to clinical attachment levels in LJP patients. 相似文献
109.
JAIME VILA MARÍA NIEVES PÉREZ MARÍA DEL CARMEN FERNÁNDEZ JOAQUÍN PEGALAJAR MARÍA SÁNCHEZ 《Psychophysiology》1997,34(4):482-487
How cardiac components of the defense reaction are modulated by attentional factors related to sensory intake versus sensory rejection was examined. Forty-eight men participated in a test of the heart rate response to three presentations of an intense auditory stimulus while performing one of three attentional tasks during the 80 s following stimulus onset: (a) internal (rejection) task, (b) external (intake) task, and (c) no task. Results showed a potentiation of the defense response only under the external attention condition. We concluded that defensive reactions, far from provoking the rejection of the aversive stimulus, require allocation of attention to processing that stimulus in detail. 相似文献
110.
Objective : To define the individual neonatal response to the artificial surfactant, Exosurf, and factors that may influence the response.
Methodology : Eighty-two consecutive, preterm neonates with respiratory distress syndrome, who received Exosurf at <12h of age were studied. Their response was categorized from the graphical change in the oxygenation index with postnatal age, for 12h after each of two doses of surfactant and assessed independently by two observers. Clinical factors were analysed for their effect on the four pre-defined categories of response, namely: none; mild; good; relapsed; and good: sustained.
Results : Within the first 12h, 11% of the neonates showed no response, 5% a mild response and 84% a good response, but 34% relapsed. By 24h, 6% still showed no response (all died), 11% showed a mild response and 83% a good response, of whom half relapsed. At 24h, no response was significantly associated with low gestational age and asphyxia mild response with less severe lung disease. According to the response there was a gradation in the risk of death during the first week.
Conclusions : The response to Exosurf can be individually and reproducibly categorized and demonstrated that 83% of neonates had a good response but half relapsed. No response was associated with extreme prematurity and asphyxia 相似文献
Methodology : Eighty-two consecutive, preterm neonates with respiratory distress syndrome, who received Exosurf at <12h of age were studied. Their response was categorized from the graphical change in the oxygenation index with postnatal age, for 12h after each of two doses of surfactant and assessed independently by two observers. Clinical factors were analysed for their effect on the four pre-defined categories of response, namely: none; mild; good; relapsed; and good: sustained.
Results : Within the first 12h, 11% of the neonates showed no response, 5% a mild response and 84% a good response, but 34% relapsed. By 24h, 6% still showed no response (all died), 11% showed a mild response and 83% a good response, of whom half relapsed. At 24h, no response was significantly associated with low gestational age and asphyxia mild response with less severe lung disease. According to the response there was a gradation in the risk of death during the first week.
Conclusions : The response to Exosurf can be individually and reproducibly categorized and demonstrated that 83% of neonates had a good response but half relapsed. No response was associated with extreme prematurity and asphyxia 相似文献