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51.
Objective. To perform an initial screening study of methicillin-resistant Staphylococcus aureus (MRSA) contamination in an ambulance fleet. Methods. This was a cross-sectional study of MRSA contamination in an ambulance fleet operating in the western United States in June 2006. Five specific areas within each of 21 ambulances (n = 105) were tested for MRSA contamination using dacron swabs moistened with a 0.85% sterile saline solution. These samples were then plated onto a screening media of mannitol salt agar containing 6.5% NaCl and4 mcg/mL oxacillin. Results. Thirteen samples isolated from 10 of the 21 ambulances (47.6%) in the sample group tested positive for MRSA. Conclusions. The results of this preliminary study suggest that ambulances operating in the emergency medical services (EMS) system may have a significant degree of MRSA contamination andmay represent an important reservoir in the transmission of potentially serious infections to patients. 相似文献
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54.
The safe and effective management of aggression has become an increasingly critical skill for mental health nurses, particularly those working in acute inpatient settings. There is considerable evidence to suggest that the psychological constructs of self-efficacy and locus of control are closely related to work performance in a variety of occupations. By drawing upon literature published in the past 15 years, this paper highlights this evidence and draws attention to the relationship between self-efficacy and locus of control. The central argument of the paper is that there may be direct relationships among mental health nurses” self-efficacy, their degree of internality or externality in relation to locus of control, and their ability to safely and effectively manage aggressive incidents. We argue the need to further investigate these relationships and discover whether these variables can be modified through professional development activities. 相似文献
55.
Margaret M. Dunn 《American journal of surgery》2010,200(4):558-152
A new job is a great opportunity to change and enhance your professional and personal life. Your new position will be defined through negotiation with the parties supporting your new position. Whether your new job is your first or your last, with a large organization or solo, urban or rural, the goal is the same, to define your expectations and communicate clearly to create a situation that you will find professionally and personally fulfilling. 相似文献
56.
BACKGROUND: In men with spinal cord injury (SCI), fertility is impaired because of a combination of ejaculatory dysfunction and poor semen quality. We hypothesized that ultrastructural and metabolic abnormalities of sperm could be an underlying factor in infertility in these men. METHODS: To investigate mechanisms contributing to the abnormal sperm parameters, we analyzed seminal constituents and sperm ultrastructure in ejaculates from 7 men with SCI and compared them with 5 control subjects. Sperm adenosine triphosphate (ATP) content was measured using a firefly luciferase bioluminescent assay kit, and ultrastructure was evaluated by electron microscopy. Seminal oxidative stress (8-iso-prostaglandin F-2alpha [8-iso-PGF2alpha]) and transforming growth factor-beta1 (TGF-beta1) levels were measured by specific enzyme-linked immunoabsorbent assay kits. RESULTS: Semen samples from men with SCI showed azoospermia (3) and severe asthenospermia (2; motility 0-5%). A majority (65%) of sperm from asthenospermic samples showed degenerative changes and significant axonemal defects. Incubation of normal sperm with SCI seminal plasma induced a concentration-dependent decrease in sperm motility (43%) accompanied by a significant drop in intracellular ATP content (33%). Semen samples from men with SCI exhibited levels of 8-iso-PGF2alpha 3.5-fold higher than those from controls and levels of TGF-beta1 that were 10% higher than those from controls. CONCLUSION: Our results suggest that seminal constituents of men with SCI are detrimental to sperm movement and that ultrastructural degenerative changes may contribute to the impaired sperm motility and viability seen in these patients. These preliminary results must be confirmed in larger patient populations and longitudinal studies. 相似文献
57.
The role of laparoscopy in penetrating abdominal trauma. 总被引:1,自引:0,他引:1
Erik J Miles Ernest Dunn Dot Howard Alicia Mangram 《JSLS, Journal of the Society of Laparoendoscopic Surgeons》2004,8(4):304-309
BACKGROUND: Minimally invasive surgery has become increasingly utilized in the trauma setting. When properly applied, it offers several advantages, including reduced morbidity, lower rates of negative laparotomy, and shortened length of hospital stay. The purpose of this study was to evaluate the role of laparoscopy in the management of trauma patients with penetrating abdominal injuries. METHODS: We conducted a 3-year retrospective chart review of 4541 trauma patients admitted to our urban Level II trauma center. Penetrating abdominal injuries accounted for 209 of these admissions. Patients were divided into 3 treatment groups based on the characteristics of their abdominal injuries. Management was either observation, immediate laparotomy, or screening laparoscopy. RESULTS: Thirty-three patients were observed in the Emergency Department based on their initial physical examination and radiologic studies. After Emergency Department evaluation, 154 patients underwent immediate laparotomy. In this group, 119 therapeutic laparotomies, 11 nontherapeutic laparotomies, and 24 negative laparotomies were performed. A review of the negative laparotomies revealed that possibly 8 of 10 gun shot wounds and all 14 stab wounds could have been done laparoscopically. Twenty-two patients underwent laparoscopic evaluation, 9 of which were converted to open procedures. CONCLUSION: Minimally invasive surgical techniques are particularly helpful as a screening tool for anterior abdominal wall wounds and lower chest injuries to rule out peritoneal penetration. Increased use of laparoscopy in select patients with penetrating abdominal trauma will decrease the rate of negative and nontherapeutic laparotomies, thus lowering morbidity and decreasing length of hospitalization. As technology and expertise among surgeons continues to improve, more therapeutic intervention may be done laparoscopically in the future. 相似文献
58.
R Binder P J Stone J D Calore D M Dunn G L Snider C Franzblau C R Valeri 《Respiration; international review of thoracic diseases》1985,47(4):267-277
In order to assess blood factors which might explain why some cigarette smokers develop airflow obstruction while others do not, we compared two groups of PiM phenotype volunteers matched for age, sex and total pack-years of cigarette smoking; one group had airflow obstruction and the other did not. Functional levels of alpha-2-macroglobulin (alpha-2-M) and alpha-1-protease inhibitor (alpha-1-PI) were separately assessed by a protease binding procedure. Neutrophils were isolated from blood by counterflow centrifugation, and their elastase content was assayed with 3H-elastin-SDS (sodium dodecyl sulfate). The obstructed and nonobstructed groups were not different with respect to functional or immunoreactive levels of alpha-1-PI and alpha-2-M or elastase levels in their neutrophils. We do not find imbalances of circulating elastase or antielastase levels in PiM phenotype smokers with airflow obstruction. 相似文献
59.
The functional significance of coronary collateral flow from a nonobstructed supply artery was studied in 121 patients with severe (greater than or equal to 80%) single-vessel disease, 64 with and 57 without Q wave infarction. All patients underwent exercise thallium imaging and coronary angiography. On angiography, collateral flow was present in 85% of 74 occluded arteries compared with only 17% of 47 arteries with subtotal obstruction (p less than .001). Collateral flow was not seen in arteries with lesions of less than 90% obstruction. Collateral flow was present in 100% of 29 occluded arteries in patients without Q wave infarction compared with only 76% of 45 occluded arteries with Q wave infarction (p less than .005). Clinical variables did not correlate with collateral flow. Collateral flow did not prevent ischemia on exercise thallium imaging in patients without Q wave infarction: 30 of 33 (91%) with collateral flow had reversible thallium defects compared with 24 of 24 (100%) without collateral flow (p = NS). In patients with Q wave infarction, partially reversible exercise thallium defects (peri-infarctional ischemia) were more common with flow to the area from either subtotal obstruction (73%) or collateral flow (45%) than with no flow from total occlusion (27%; p = .05). In patients with severe single-vessel disease the presence of collateral flow is principally determined by coronary occlusion. Collateral flow may protect from Q wave infarction but does not prevent exercise ischemia on thallium imaging. 相似文献
60.
Siobhán Stynes Kika Konstantinou Kate M. Dunn Martyn Lewis Elaine M. Hay 《European spine journal》2016,25(9):2734-2740