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121.
Most disaster plans depend on using emergency physicians, nurses, emergency department support staff, and out-of-hospital personnel to maintain the health care system's front line during crises that involve personal risk to themselves or their families. Planners automatically assume that emergency health care workers will respond. However, we need to ask: Should they, and will they, work rather than flee? The answer involves basic moral and personal issues. This article identifies and examines the factors that influence health care workers' decisions in these situations. After reviewing physicians' response to past disasters and epidemics, we evaluate how much danger they actually faced. Next, we examine guidelines from medical professional organizations about physicians' duty to provide care despite personal risks, although we acknowledge that individuals will interpret and apply professional expectations and norms according to their own situation and values. The article goes on to articulate moral arguments for a duty to treat during disasters and social crises, as well as moral reasons that may limit or override such a duty. How fear influences behavior is examined, as are the institutional and social measures that can be taken to control fear and to encourage health professionals to provide treatment in crisis situations. Finally, the article emphasizes the importance of effective risk communication in enabling health care professionals and the public to make informed and defensible decisions during disasters. We conclude that the decision to stay or leave will ultimately depend on individuals' risk assessment and their value systems. Preparations for the next pandemic or disaster should include policies that encourage emergency physicians, who are inevitably among those at highest risk, to "stay and fight."  相似文献   
122.
AIM: Small dense LDL particles are associated with an increased risk of coronary heart disease and are prevalent in obesity related dyslipidaemia. This study evaluated the effect of weight loss in nine children (BMI 33.4 +/- 8.4 kg.m(-2) and age 15.1 +/- 2.9 years) on LDL peak particle size, and cholesterol concentrations within particular LDL sub-fractions. METHODS: Each child undertook fun based physical activity, dietary restriction and modification and lifestyle education classes in a residential summer weight loss intervention. Blood was drawn before and after intervention and LDL heterogeneity measured by ultracentrifugation. RESULTS: The mean change in body weight were -6.8 +/- 4.9 kg, BMI units -2.5 +/- 1.4 kg.m(-2), and waist circumference -6.3 +/- 6.3 cm (all p < 0.01). Absolute LDL-c concentration reduced from 106.2 mg/dL to 88.3 mg/dL (p < 0.01). The cholesterol contained within the small dense LDL sub-fraction (LDL-c III) reduced from 54.1 mg/dL to 40.4 mg/dL (p < 0.01). Peak particle density decreased from 1.041g/mL to 1.035g/mL (p < 0.01). At pre intervention 50.9% of absolute cholesterol was within LDL-c III particles, changing to 46.2%. CONCLUSION: Mean weight loss of -6.8 +/- 4.9 kg lowers absolute LDL-c and the cholesterol specifically within LDL-c III particles. LDL peak particle size increased and a degree of LDL particle remodelling occurred. These favourable adaptations, accrued in a matter of 4 weeks, maybe associated with a reduction in CHD risk.  相似文献   
123.
Objective To assess the diagnostic value of chest radiographs in patients presenting to a busy inner-city Emergency Department with subsequently proven acute aortic dissection. Methods A retrospective review of initial chest radiographs and charts of patients with the confirmed diagnosis of acute aortic dissection was done for a period of 5 years from 1998 to 2003. A comparison was made between the initial readings of chest radiographs prior to confirmation of the aortic dissection, and a retrospective review of the same radiographs by two board-certified radiologists with special attention to the classic findings of acute aortic dissection identifiable on plain films. Results The charts of nine patients (four men, five women) with proven acute aortic dissection were reviewed. All nine patients were suspected of having acute aortic dissection based on presenting history and symptoms of chest pain (66% ), migratory pain (89% ), back pain (89% ), and the abruptness of onset of pain (89% ). Initial plain portable chest X-rays were obtained in the Emergency Department in all nine patients. Six of nine (67%) radiographs were read as normal, while three (33%) demonstrated a widened mediastinum (> 8.0cm), two (22%) showed an abnormal aortic contour, with one ( 11% ) displaying an apical cap. Confirmation of the diagnosis was obtained with either a spiral CT angiogram or transesophageal echocardiography (TEE). All nine plain radiographs were retrospectively reviewed by two board-certified radiologists aware of the diagnosis of acute dissection without a change in the readings. Conclusions Plain portable chest radiographs are of limited usefulness for the screening of acute aortic dissection. Further radiologic evaluation should be dictated by the clinical presentation and an awareness of the low sensitivity of portable chest X- rays.  相似文献   
124.
Pain can begin in the first year of life for individuals with sickle cell disease (SCD) and continue in an unpredictably recurrent manner throughout their life span. Sickle vaso-occlusive pain (sickle pain) can also occur simultaneously with pain of other origins, complicating both assessment and management. Aims of this research were to describe the reliability and validity of a daily diary for data collection with children and adolescents with SCD and to describe characteristics of vaso-occlusive sickle pain episodes (VOE) and other pain reported by children and adolescents with SCD along with home pain management strategies. Thirty-nine children and adolescents (mean age, 10.9 +/- 3.6 years) completed diaries twice daily at home for up to 3 years (mean, 417.9 +/- 272.2 diary days) with excellent compliance. Sickle pain alone was reported on 8.4% of days (n = 1515 days), whereas other pain occurred on 2.7% of days (n = 490) and both sickle pain and other pain on 5.7% (n = 1041 days). Other pain only episodes were shorter and involved fewer sites than sickle pain only episodes. Sickle pain occurred in the extremities and hips, whereas most other pain occurred in the head-neck area. Analgesic medication was taken on 85% of days of sickle pain, whereas analgesics were taken on only 60% of days with other pain. The diary used in this study is a valid and reliable self-report tool. The use of home diaries will improve the understanding of sickle pain and its management and assist in identifying other pain syndromes that may require alternative management.  相似文献   
125.
The cause of chronic lung disease of early infancy, often called bronchopulmonary dysplasia (BPD), remains unclear, partly because large-animal models that reliably reproduce BPD have not been available. We developed a model of BPD in lambs that are delivered prematurely and ventilated for 3 to 4 wk after birth to determine whether the histopathology of chronic lung injury in premature lambs mimics that which occurs in preterm infants who die with BPD, and to compare two ventilation strategies to test the hypothesis that differences in tidal volume (VT) influence histopathologic outcome. The two ventilation strategies were slow, deep ventilation (20 breaths/min, 15 +/- 2 ml/kg body weight VT; n = 5) or rapid, shallow ventilation (60 breaths/min, 6 +/- 1 ml/kg body weight VT; n = 5). Lambs were delivered at 125 +/- 4 d gestation (term = 147 d), treated with surfactant, and mechanically ventilated with sufficient supplemental oxygen to maintain normal arterial oxygenation (60 to 90 mm Hg). Quantitative histologic analysis revealed lung structural abnormalities for both groups of experimental lambs compared with lungs of control term lambs that were < 1 d old (matched for developmental age; n = 5) or 3 to 4 wk old (matched for postnatal age; n = 5). Compared with control lambs, chronically ventilated preterm lambs had pulmonary histopathology characterized by nonuniform inflation patterns, impaired alveolar formation, abnormal abundance of elastin, increased muscularization of terminal bronchioles, and inflammation and edema. Slow, deep ventilation was associated with less atelectasis, less alveolar formation, and more elastin when compared with rapid, shallow ventilation. We conclude that prolonged mechanical ventilation of preterm lambs disrupts lung development and produces pulmonary histopathologic changes that are very similar to those that are seen in the lungs of preterm infants who die with BPD. This chronic lung disease is not prevented by surfactant replacement at birth, does not appear to require arterial hyperoxia, and is influenced by VT.  相似文献   
126.
Identification of a polymorphic Plasmodium vivax microsatellite marker   总被引:2,自引:0,他引:2  
Microsatellite markers derived from simple sequence repeats have been useful in studying a number of human pathogens, including the human malaria parasite Plasmodium falciparum. Genetic markers for P. vivax would likewise help elucidate the genetics and population characteristics of this other important human malaria parasite. We have identified a locus in a P. vivax telomeric clone that contains simple sequence repeats. Primers were designed to amplify this region using a two-step semi-nested polymerase chain reaction protocol. The primers did not amplify template obtained from non-infected individuals, nor DNA from primates infected with the other human malaria parasites (P. ovale, P. malariae, or P. falciparum). The marker was polymorphic in P. vivax-infected field isolates obtained from Papua New Guinea, Indonesia and Guyana. This microsatellite marker may be useful in genetic and epidemiologic studies of P. vivax malaria.  相似文献   
127.
128.
The goal of this study was to verify the existence and prevalence of large vessel lesions outside the central nervous system in young patients with sickle cell disease. Thus, 17 spleens resected because of episodes of sequestration or infarction and 41 controls were studied. Anomalies of arteries and veins were detected in all spleens from sickle cell disease patients, but no definite correlation with age, sex, type of sickle hemoglobin, or frequency of sequestration episodes could be established. The most consistent lesions were intimal proliferation affecting large arteries and veins, reduplication of the internal elastic lamina of large arteries, and a lesion not previously documented in this condition, that of subendothelial infiltration of the large veins by activated T cells. Endotheliitis showing some similarity with the one seen in sickle cell disease spleens was noted in 5 of 41 spleens of patients who did not suffer from sickle cell disease. However, when present it was usually mild. Very limited damage to the arterial elastica was noted in only 1 of the 41 controls. Minimal endothelial proliferation was seen in 2 of 41 controls. Received December 28, 2000; accepted March 15, 2001.  相似文献   
129.
Several recent studies have documented that signaling can be fundamentally different in vivo and in vitro. However, studies of signaling and cytokine production by macrophages are often conducted in vitro, without confirmation in vivo. In addition, the direct effects of drugs and chemicals, including ethanol, on these processes are also often investigated in vitro. The purpose of the present study was to compare production of interleukin-6 (IL-6), IL-10, and IL-12 by macrophages in response to two different ligands for toll-like receptors and the effects of acute ethanol exposure on these responses in vivo and in vitro. The macrophage-like cell line RAW 264.7 is also widely used in cytokine and signaling studies, so these cells were also evaluated in this study. The results indicate that IL-6 production and the effects of Ethanol on IL-6 were similar in vivo and in vitro. In contrast, IL-10 was produced to a much greater extent in vitro than in vivo, and IL-12 was often undetectable in vitro even though it was produced at greater concentrations than IL-10 in vivo. To determine the role of altered secretion of preformed IL-10 as compared to new synthesis, cells were treated in vitro with protein and mRNA synthesis inhibitors. The results suggest that preformed IL-10 is released in vivo, but almost all IL-10 secreted in vitro is newly synthesized. Ethanol suppressed IL-12 and enhanced or had no effect on IL-10 production in vivo, whereas it decreased IL-10 production in vitro. These effects were similar at different times and using different concentrations of toll-like receptor ligands. In general, RAW 264.7 cells responded similarly to peritoneal macrophages in vitro. This suggests that results for cytokine studies and probably signaling studies as well that are conducted in vitro should be interpreted with caution and confirmed in vivo, particularly if they involve IL-10 and IL-12.  相似文献   
130.
Objective/Hypothesis One European multicenter study has reported favorable outcomes after ossicular reconstruction with the titanium Kurz prosthesis. At the time of this study, however, no study has analyzed its outcomes when used for reconstruction after prior failure with another implant (revision reconstruction). The study reports our experience with the titanium Kurz prosthesis for revision ossicular reconstruction. Study Design A retrospective review was made of all revision ossicular reconstructions at our institution from October 1998 to September 2001. Methods Seventeen cases were reviewed. Patients were divided into two groups: patients who underwent revision ossicular reconstruction with the Kurz prosthesis and patients who underwent revision ossicular reconstruction with another prosthesis (the “other” group). Audiograms were reviewed and air–bone gaps were calculated for each patient. Results The average postoperative air–bone gap after Kurz revision was 15.6 dB, a statistically significant improvement over the average postoperative air–bone gap from the “other” revision group (P = .022). Conclusion The titanium Kurz prosthesis has been an effective implant at our institution for revision ossicular reconstruction. Future research should focus on a prospective, randomized trial comparing the Kurz prosthesis with other prostheses currently in use.  相似文献   
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