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Preterm birth remains one of the serious problems in perinatal medicine and is associated with an increased risk of neonatal complications and long-term morbidity. Although each day that delivery is delayed between 22 and 28 weeks of gestation increases survival by 3%, since most spontaneous preterm labour occurs between 28 and 34 weeks of gestation, this is of secondary concern; the primary goal of delay is to improve the function of certain systems in the fetus and to balance the risks of a hostile intrauterine environment with the complications of extrauterine preterm life. Although there is a lack of definitive evidence that tocolytic drugs improve outcome following spontaneous preterm labour and preterm birth, there is ample evidence that tocolysis delays delivery for long enough to permit administration of a complete course of antepartum glucocorticoids and to facilitate in utero transfer to a tertiary care unit where neonatal care will be optimal. Both these measures have been associated with improved outcomes; antepartum glucocorticoids reduce the incidence of respiratory distress syndrome, intraventricular haemorrhage, periventricular leucomalacia and necrotising enterocolitis, and in utero transfer is associated with decreased morbidity and mortality and less hospital-based intervention compared with postnatal transportation. Consequently, women who are more likely to benefit from tocolysis are those at early gestational ages, those needing transfer to a hospital that can provide neonatal intensive care and those who have not yet received a full course of antepartum glucocorticosteroids. In these cases, delaying labour for at least 48 hours with drugs such as atosiban should be considered, since it offers clear advantages for the fetus.  相似文献   
124.
Cross-sectional and prospective studies of men suggest a positive association between nephrolithiasis and hypertension. However, this association remains controversial in women. We conducted a prospective study of the relation between nephrolithiasis and the risk for hypertension in the Nurses' Health Study, a cohort of 89,376 women aged 34 to 59 years in 1980. Information on the history of nephrolithiasis, physician-diagnosed hypertension, and other relevant exposures was obtained by biennial mailed questionnaire. A history of nephrolithiasis before 1980 was reported by 2,558 women (2.9%), and a history of hypertension was reported by 11,883 women (13.3%). Among women without hypertension before 1980, 12,540 women reported a new diagnosis of hypertension between 1980 and 1992, during 711,039 person-years of follow-up. Compared with those without a history of nephrolithiasis, the age-adjusted relative risk (RR) for incident hypertension in women with such a history was 1.36 (95% confidence interval [CI], 1.20 to 1.43). After further adjustment for body mass index (BMI) and the intake of calcium, sodium, potassium, magnesium, caffeine, and alcohol, the RR was only slightly attenuated (RR=1.24; 95% CI, 1.13 to 1.37). In contrast, the occurrence of incident nephrolithiasis during follow-up was similar in women with hypertension at baseline compared with women without (adjusted odds ratio [OR]=1.01; 95% CI, 0.85 to 1.20). These data are consistent with the results obtained in men and support the hypothesis that a history of nephrolithiasis is associated with an increased risk for subsequent hypertension. Dietary factors, such as the intake of calcium, sodium, and potassium, do not explain this association. Unidentified pathogenic mechanisms common to nephrolithiasis and hypertension may be responsible for the development of both disorders.  相似文献   
125.
目的:观察电针对单纯性肥胖大鼠下丘脑瘦素和神经肽Y表达的影响,探索电针减肥的机制。方法:实验于2005-12/2006-06在中南大学湘雅医院中西医结合研究所实验室完成。①取1月龄刚断乳SD雄性大鼠,随机取6只饲以普通饲料为正常对照组,其他大鼠饲以高脂饲料,喂养3个月后,选择体质量超过正常对照组20%的单纯性肥胖大鼠12只,随机分为模型组和电针组2组,每组6只。②电针组大鼠电针双侧足三里、天枢、三阴交穴,采用疏密波,电流强度0.3~0.6mA,留针20min,1次/d,共20次;其他2组不电针。实验期间均饲以普通饲料。③观察实验大鼠体质量、体长、Lee's指数及体脂,采用Western-blot技术检测下丘脑组织中瘦素、神经肽Y表达的变化。结果:18只大鼠进入结果分析。①模型组大鼠体质量和Lee’s指数高于正常对照组[(451.8±14.8),(323.6±6.8)g;324.25±1.4,305.14±1.5;P均<0.01];电针组电针后体质量和Lee’s指数低于电针前[(372.2±20.4),(454.7±19.7)g;307.71±1.5,323.56±1.6;P均<0.01]。②模型组大鼠心包、肾周和附睾脂肪量均高于正常对照组(P<0.01);电针组电针后心包、肾周和附睾脂肪量低于电针前(P<0.01)。③模型组下丘脑组织中瘦素蛋白表达低于正常对照组(0.62±0.11,0.88±0.15,P<0.01),电针组高于模型组(0.85±0.13,P<0.01);模型组下丘脑组织中神经肽蛋白表达高于正常对照组(2.42±0.27,1.75±0.24,P<0.01),电针组高于模型组(1.87±0.21,P<0.01)。结论:电针有良好的减肥效果,其作用可能与电针增强下丘脑组织瘦素蛋白的表达、同时抑制下丘脑组织中的神经肽Y蛋白表达有关。  相似文献   
126.
The mortality rate of elderly persons with heart failure is high despite the introduction of several effective therapeutic interventions during the past decade. The management of end of life, often associated with distressing symptoms and multiple hospitalizations, is a significant clinical problem. Skillful and effective management requires expert knowledge of the heart failure syndrome, but the critical dimension of care relates to detailed knowledge about a patient's comorbidities, extent of debility, values, and desires. Discussing end-of-life issues early in the course of illness is essential for determining the appropriate levels of intensity of care and for defining the circumstances in which patients wish to be hospitalized and when hospital care offers little potential for increased comfort or longevity. Early and repeated discussions are needed to consider matters such as living wills, do-not-resuscitate orders, and power of attorney. In light of the complexity of the health care system, including involvement of multiple caregivers, end-of-life issues are among the most demanding of a physician's time, but when end-of-life care is managed effectively, health care providers often are rewarded with the gratitude of patients and their families for minimizing suffering and providing optimal opportunities for patients to participate in the affairs of family and the community.  相似文献   
127.
目的 体外比较曼氏血吸虫吡喹酮敏感株与抗性株成虫阶段对吡喹酮的反应性。方法 将各虫株成熟成虫分别培养于含吡喹酮分别为 3.2× 10 - 4、8× 10 - 4、1.6× 10 - 3m ol/ L的 MEM培养液中 ,37℃孵育 15、30、4 5、6 0、75 min后 ,分别在解剖镜下观察虫体的存活状况并计算存活率。结果 当孵育于含吡喹酮 3.2× 10 - 4m ol/ L的 MEM中 75 m in,敏感株与抗性株雌虫均能存活 ;但敏感株与抗性株雄虫的存活率仅为 11.5 % - 16 .0 %和 32 .7% - 36 .5 %。孵育于含吡喹酮 8× 10 - 4m ol/L 的 MEM中 15 min,抗性株雄虫与雌虫存活率为 4 8.3% - 5 0 .0 %和 5 7.9% - 6 3.6 % ;敏感株雄虫与雌虫的存活率为 2 2 .4 % - 2 5 .9%和 38.5 % - 4 8.3% ;75 min后 ,抗性株雄虫的存活率为 13.3%- 17.3% ,敏感株雄虫的存活率则为 0。孵育于含吡喹酮 1.6× 10 - 3m ol/ L 的 MEM中 15 min,抗性株雄虫与雌虫的存活率为 11.1% - 19.6 %和 2 7.5 % - 2 9.9% ;敏感株雄虫与雌虫的存活率均为 0。结论 将曼氏血吸虫吡喹酮抗性株和敏感株成虫孵育于含一定浓度吡喹酮的 MEM中不同时间后 ,抗性株的存活率高于敏感株 ;雌虫的存活率高于雄虫  相似文献   
128.
Dooms  GC; Hricak  H; Sollitto  RA; Higgins  CB 《Radiology》1985,157(2):479-483
This retrospective study was performed to assess the potential of magnetic resonance (MR) imaging for demonstrating various types of lipomatous tumors and tumors with fatty component and to compare the results of MR with those of computed tomography (CT). MR examinations of 17 patients with 18 lipomatous tumors (16, benign; two, liposarcoma) and two patients with fibrosarcomas were reviewed; CT scans were available for comparison in all patients. In the 16 benign lesions (12 benign lipomas, two ovarian dermoid cysts, and two renal angiomyolipomas), the fatty component of the tumors was readily demonstrated by both MR and CT. The T1 and T2 relaxation times and spin density of benign lipomatous tumors were in a range similar to those of normal subcutaneous fat. Differentiation between lipomas and liposarcomas was achieved with both MR and CT. On MR images using a short repetition time (TR = .5 sec), liposarcomas (long T1) were imaged with a lower MR intensity than lipomas (short T1).  相似文献   
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130.
In 1988 and again in 1990, the National Center for Health Statistics conducted a survey of the AIDS related knowledge and beliefs of Hispanic and non-Hispanic adults in the United States. A survey of Los Angeles Hispanic women was conducted in 1990, using the 1988 survey instrument. This study is an examination of the trends in knowledge and beliefs by comparing those of Hispanic Los Angeles women in 1990 to Hispanic and non-Hispanic female respondents in the 1988 national sample. Despite intense public health, local community, and media efforts to educate the public about AIDS, the women in the Los Angeles sample did not show appreciable differences in knowledge and beliefs compared with the 1988 national sample, and in many areas they were less knowledgeable. These results may be related to differing education and acculturation levels as well as possible differences in ethnicity. Hispanic groups will need focused prevention efforts which take into account specific areas of knowledge, educational level of information, adherence to traditional beliefs and practices, and ethnicity of the targeted community.  相似文献   
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