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991.
The presence of the human T cell lymphotropic virus (HTLV-I/II) in South America is well established. Its origin and spectrum in the continent still remain a matter of debate. There are signs now that HTLV-I/II was already present in the Amerindian population coming originally from Asia and that HTLV-I was also introduced with African slave trade and with immigration of individuals from endemic areas of Japan. South America has approximately 350 million inhabitants in its 13 countries. The presence of HTLV-I/II has been reported with impressive numbers in most of them and may be considered endemic in this continent. The distribution of HTLV I/II among native Amerindian populations has shown a geographic clustering of type I in the Andean highlands and Brazilian coast, while type II predominates in lowlands of South America. Although comparability between studies conducted among blood donors in different countries may be difficult, the data indicate that the viruses are also circulating among otherwise healthy individuals. Undoubtedly, HTLV-I/II infection and its related diseases should be considered a public health concern in South America and measures to prevent its spread should be emphasized.  相似文献   
992.
Pulmonary ventilation is adjusted to maintain balance between O2 demands and CO2 elimination, which is essential for acid–base status in land ectothermic vertebrates. Rising temperatures cause increases in O2 consumption (Q10 effect) and decreases in the O2 affinity of hemoglobin (a rightward shift in the oxygen–hemoglobin dissociation curve). These changes in air-breathing ectotherms are not proportional, i.e., the increased ventilation is relatively smaller than the change in metabolic rate. Therefore, the ratio between ventilation and metabolic rate is reduced, and consequently blood pH changes inversely with temperature. The combination of high temperatures and hypoxia exposure results in an amplified increase of ventilation, which may be explained by the balance between increased O2-demand and decreased O2-supply as well as increased O2-chemoreceptors sensitivity. High temperature also increases pulmonary diffusing capacity. Global warming is expected to have significant impacts on the world’s climate, with temperature changes affecting living organisms, in relation to their physiology and distribution. These physiological mechanisms and their capacity to respond appropriately to temperature illustrate the complexity of the relationship between ambient temperature and the respiratory function in ectothermic vertebrates, which are particularly susceptible to change in their environment.  相似文献   
993.
《Chronobiology international》2013,30(4-5):571-589
The homeostatic control of physiological processes is affected by a variety of temporal programs, such as circadian rhythms, estrous cycles, and circannual rhythms. The existence of circaseptan rhythms (endogenous rhythms with the duration of a week) has been postulated but not properly verified. In this study, we compared plasma concentration of lactic acid, systolic and diastolic blood pressure, and rectal temperature in athletic horses (maintained under a weekly training schedule) with those in sedentary horses (maintained under a constant schedule throughout the week). Although exercise had robust acute effects on the measured parameters, measurements conducted early in the morning or in the evening showed significant weekly rhythmicity only in one of the parameters (plasma concentration of lactic acid) in a few animals. This rhythmicity was feeble, was present only in athletic horses, and vanished if rigorous statistical criteria were applied. In contrast, 24 h rhythmicity was significant in all parameters in all horses. We conclude that the overall 7-day pattern in physiological parameters of the horse is feeble and is caused by the weekly schedule of activity. The available evidence does not support the notion of endogenous, circaseptan rhythms.  相似文献   
994.
This article is a brief review of baroreflex physiology, the definition and functional meaning of baroreflex sensitivity, and the methods used to measure baroreflex sensitivity. The arterial baroreflex is important for haemodynamic stability and for cardioprotection, and it has convincingly been demonstrated that baroreflex sensitivity, even when assessed with different methods, has a strong prognostic value. Development of new baroreflex assessing procedures is still ongoing, with a focus on increased reliability in difficult measuring circumstances, e.g., in patients with a weak baroreflex and in patients with frequent arrhythmias.  相似文献   
995.

Background

The present study addressed how 92% oxygen administration affects cognitive performance, blood oxygen saturation (SpO2), and heart rate (HR) of intellectually and developmentally disabled people.

Methods

Seven males (28.9 ± 1.8 years) and seven females (34.4 ± 8.3 years) with intellectual and developmental disabilities (disabled level 2.1 ± 0.5) completed an experiment consisting a 0-back task with normal air (21% oxygen) administered in one run and hyperoxic air (92% oxygen) administered in the other run. The experimental sequence in each run consisted of a 1-min adaptation phase, 2-min control phase, and 2-min 0-back task phase, where SpO2 and HR were gauged for each phase.

Results

The administration of 92% oxygen increased 0-back task performance of intellectually and developmentally disabled people, in association with increased SpO2 and decreased HR. Our results demonstrate that sufficient oxygen supply subserving cognitive functions, even as a short-term effect, could increase cognitive ability for the intellectually and developmentally disabled people.

Conclusions

It is concluded that enriched oxygen can positively affect, at least in the short-term, the working memory of those with intellectual and developmental disability.  相似文献   
996.
为探讨不同低氧环境适应动物的血液理化特征,用美国雅培手掌血气分析仪分别测定常氧适应4周的高原鼢鼠(Myospalax baileyi)及甘肃鼢鼠(M.cansus)血液的血气、酸碱及电解质指标,并与SD大鼠(Rattus norvegicus)进行比较。结果显示,常氧适应后,甘肃鼢鼠与高原鼢鼠动脉氧分压(PaO2)、静脉氧分压(PvO2)、动静脉氧分压差(PaO2﹣PvO2)、动脉氧饱和度(SaO2)、静脉氧饱和度(SvO2)及氧利用率均无显著性差异,两种动物静脉血的氧分压和氧饱和度均极显著低于SD大鼠,氧利用率极显著高于SD大鼠;高原鼢鼠与甘肃鼢鼠动、静脉血红蛋白(Hb)及动、静脉红细胞压积(HCT)无显著性差异,血红蛋白含量与SD大鼠无显著性差异,但红细胞压积(HCT)极显著低于SD大鼠;高原鼢鼠和甘肃鼢鼠血液酸碱特征趋于一致,不同于SD大鼠,动静脉pH差(pHa﹣pHv)及动静脉CO2总含量差(TvCO2﹣TaCO2)显著高于SD大鼠,动脉二氧化碳分压(PaCO2)极显著低于SD大鼠,动静脉二氧化碳分压差(PvCO2﹣PaCO2)极显著高于SD大鼠;高原鼢鼠和甘肃鼢鼠血浆中钠离子(Na+)浓度、钾离子(K+)浓度、游离钙离子(iCa2+)浓度及动静脉钠离子浓度差(Na+v﹣Na+a)、钾离子浓度差(K+v﹣K+a)和游离钙离子浓度差(iCa2+v﹣iCa2+a)无显著性差异;高原鼢鼠动脉血钾离子浓度显著低于SD大鼠,钾离子浓度差显著高于SD大鼠;甘肃鼢鼠钾离子浓度差及动、静脉血钙离子浓度显著高于SD大鼠。这些结果说明,低氧适应动物血气、酸碱及电解质特征一致,与地面生活的SD大鼠差异很大,表现出较低的红细胞压积和较高的氧利用率,血液能耐受较宽范围的酸碱变化,维持电解质稳定,保证内环境稳态。  相似文献   
997.
998.
ObjectiveTo assess blood glucose in patients with uncontrolled type 2 diabetes mellitus treated with oral antidiabetic drugs in primary care at the time of referral to specialized endocrinologists, and the degree of implementation of the national consensus guidelines of the Spanish Society of Diabetes by evaluating steps one (S1), two (S2), and three (S3) of the escalating therapy.Material and methodsRetrospective, observational study where 81 endocrinologists evaluated patients ≥40 years of age referred from primary care between July 2012 and July 2013, treated with 1 to 2 oral antidiabetic drugs but no insulin therapy, and with glycosylated hemoglobin (HbA1c) levels ≥6.5%. Patients also had to have HbA1c levels and both fasting and postprandial plasma glucose measurements from the previous three months.ResultsA total of 285 patients (57.6% males) were assessed. Mean (SD) age was 63.1 (9.7) years, mean HbA1c was 8.5 (1.2) %, mean FPG was 171.7 (43) mg/dL, and mean postprandial plasma glucose was 206.8 (50) mg/dL. In primary care, 26.0% of patients were at S1 and 74.0% were at S2. After referral to the endocrinologist, 9.8% of patients moved onto S1, 42.8% onto S2, and 47.4% onto S3. Oral antidiabetic drugs most commonly prescribed in primary care were metformin (90.2%), DPP-4 inhibitors (34.4%), and sulfonylureas (30.5%), while drugs most commonly used in the specialized endocrinology setting were metformin (86%), insulin (56.8%), and DPP-4 inhibitors (49.8%). The most commonly followed guidelines were those of the American Diabetes Association and the consensus guidelines of the Spanish Society of Diabetes, in 77% and 45% of cases respectively.ConclusionsApproximately half the patients treated with oral antidiabetic drugs in primary care are prescribed insulin after referral to an endocrinology specialist. The most commonly followed guidelines in specialized care are the American Diabetes Association guidelines.  相似文献   
999.
目的:研究回生口服液对晚期非小细胞肺癌患者血浆纤维蛋白原和血小板水平的影响。方法:选取2011年1月至2013年7月已被收治的112例晚期非小细胞肺癌患者按照知情同意原则随机分为治疗组(60例)和对照组(52例)两组,治疗组在支持、对症治疗的基础上口服回生口服液治疗,对照组仅给予支持、对症治疗,4周后观察两组患者经两种不同的治疗方案治疗后患者血浆纤维蛋白原及血小板水平变化。结果:治疗组经给药治疗后血浆纤维蛋白原及血小板水平与治疗前相近,差异均无统计学意义(P〉0.05);对照组经治疗后血浆纤维蛋白原及血小板水平较治疗前高,差异均有统计学意义(P〈0.05);治疗组给药治疗后血浆纤维蛋白原及血小板水平均较对照组低,差异均有统计学意义(P〈0.05)。结论:回生口服液可能是通过降低血浆纤维蛋白原及血小板的含量从而改善晚期非小细胞肺癌患者的血液高凝状态。  相似文献   
1000.
刘涛  张旎娴  何凤  张丹  项方  卢斌 《生物磁学》2014,(2):368-371
肿瘤的生物治疗尤其是用免疫活性细胞输注的过继免疫治疗是目前研究热点之一,是继手术、放疗、化疗三大常规治疗的又一新的治疗肿瘤的方法。此疗法不仅是常规抗肿瘤治疗的补充,更是为晚期不宜手术或无法承受放疗化疗所带来的副作用的患者开辟了一个新的治疗途径,可取得常规方法无法达到的疗效,成为人类抗击肿瘤最有希望的战略措施之一。细胞因子诱导的杀伤细胞是用于肿瘤过继免疫治疗较为有效的免疫效应细胞之一,是目前所知杀伤活性最高的肿瘤杀伤细胞,具有增殖速度快、杀瘤活性高、杀瘤谱广的特点,对正常骨髓造血前体毒性小,已大量应用于临床。脐血CIK细胞增殖速度、杀瘤活性优于外周血CIK细胞,移植后移植物抗宿主病发生率更低等优点,因而受到广泛关注。本文就脐血CIK细胞的抗肿瘤研究的特点及,临床应用进展作一综述。  相似文献   
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