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51.
This review summarizes published as well as preliminary data on the biology of erythropoietin (Epo) in the developing and mature human central nervous system (CNS). Both Epo receptor (Epo-R) and Epo gene expression underlie developmental changes and a brain-specific regulation. These features suggest a different role of Epo in normal brain development than in neuroprotection and neuronal tissue repair after brain injury. Epo concentrations in the cerebrospinal fluid may have primary paracrine effects. While the transport of Epo across the intact blood brain barrier (BBB) is generally limited in humans, systemically produced or administrated Epo may cross during BBB dysfunction. Summarized data of the in vivo and in vitro effects of Epo in the CNS show significant neuroprotective and neurotrophic effects of this molecule. These effects are mediated by several mechanisms, including the activation of a variety of genes and their consecutive protein production. Therapeutic strategies involving activation of the CNS Epo-R are discussed, including the potential use of Epo mimetic peptides.  相似文献   
52.
Experience in the United States with intact abdominal aortic aneurysm repair   总被引:11,自引:0,他引:11  
OBJECTIVES: The purpose of this study was to determine the current outcome in the United States and to identify predictors of mortality and "bad outcome" after open, intact abdominal aortic aneurysm (AAA) repair. METHODS: In a retrospective analysis, data were obtained from the Nationwide Inpatient Sample during 1994-1996. The Nationwide Inpatient Sample is a 20% all-payer stratified sample of nonfederal United States hospitals. Patients older than 49 years were identified by the presence of primary diagnostic (441.4-intact AAA) and procedure (38.44-resection of abdominal aorta with replacement) codes of the International Classification of Diseases, Ninth Revision (ICD-9 ). In-hospital mortality rate, discharge disposition, bad outcome (death or discharge to an institution), complications (ICD-9 postoperative codes), length of stay, and charges were determined. The mortality rate and bad outcome were analyzed by the use of patient demographics (age, sex, race), patient comorbidities (ICD-9 diagnostic codes), calendar year, and hospital characteristics (size, location, teaching status) with univariate and multivariate analyses. RESULTS: We identified 16,450 intact AAAs repairs during the study years. The mean patient age was 72 +/- 7 (+/- SD) years, and most patients were male (79.7%) and white (94.6%). Most repairs were performed at large (67.3%), urban (92.5%), and nonteaching (66.7%) institutions. The in-hospital mortality rate was 4.2%, the overall complication rate was 32.4%, and 91.2% of patients were discharged home, whereas the bad outcome rate was 12.6%. The median length of stay was 8 days (mean, 10.0 +/- 8.1), and median hospital charges were $28,052 (mean, $35,681 +/- $33,006) in 1996 dollars. Multivariate analysis showed that the mortality rate (P <.05) increased with age (70-79 years, 1.8 odds ratio [OR] [95% CI, 1.4-2.3], > 79 years, 3.8 OR [95% CI, 2.9-4.9]), sex (female, 1.6 OR [95% CI, 1.3-1.9]), cerebral vascular occlusive disease (1.8 OR [95% CI, 1.3-2.5]), preoperative renal insufficiency (9.5 OR [95% CI, 7.7-11.7]), and more than three comorbidities (11.2 OR [95% CI, 3.6-35.4]). Multivariate analysis also showed that bad outcome was associated with the same variables in addition to hospital size (small/medium), year of procedure (1996), chronic obstructive pulmonary disease, and two to three comorbidities. CONCLUSIONS: Outcome after open repair of intact AAA across the United States is quite good. Older, sicker patients may benefit from nonoperative treatment or the potentially lower risk endovascular approaches.  相似文献   
53.
54.
BACKGROUND: Consent rates for brain donation were examined in 140 healthy elderly participants of the Oregon Brain Aging Study, a longitudinal study of successful aging. Subjects were initially selected for good health. The study population had a relatively high education level, a high socioeconomic status, and were predominantly white. METHODS: At each annual examination, a project physician asked participants to consider brain donation. This analysis examined variables that may affect the rate of brain donation consent: age, gender, education, socioeconomic status, marital status, religiosity, cognitive status, depression, and functional status. RESULTS: Of these variables only age was a meaningful factor. CONCLUSION: The oldest old participants (> or =85 years of age) were more likely to consent to donation than the younger participants (65-84 years of age).  相似文献   
55.
56.
Interobserver variation in the interpretation of abdominal radiographs   总被引:2,自引:0,他引:2  
A total of 140 sets of abdominal radiographs were reviewed independently by four qualified diagnostic radiologists. The degree of interobserver agreement was determined by calculating kappa values for 19 commonly used radiographic signs and diagnoses. There was fair to excellent interobserver agreement for 11 signs and diagnoses and poor agreement for the remaining eight. The signs and diagnoses for which agreement is poor cannot be considered reliable and include particularly large bowel obstruction and nonspecific gas pattern.  相似文献   
57.
Effect of intersection spacing on MR image contrast and study time   总被引:1,自引:0,他引:1  
Kneeland  JB; Shimakawa  A; Wehrli  FW 《Radiology》1986,158(3):819-822
The effects of section separation on image contrast and calculated T1 relaxation times were investigated in healthy volunteers and a phantom using an early commercial version magnetic resonance imaging system. The effects are explained qualitatively on the basis of side lobes of excitation occurring outside the selected section resulting in reduction of the time permitted for T1 relaxation. The options for dealing with imperfect section selection, including separation of the sections (i.e., leaving gaps) and nonsequential excitation, are illustrated and the trade-offs involved in each explained.  相似文献   
58.
This review summarizes the biology of thrombopoietin (TPO) in childhood. Studies on TPO and its receptor (c-mpl) have improved the understanding of inherited and acquired thrombocytopenias in childhood. Data are presented in this review regarding the molecular biology of TPO, differences in cellular effects on megakaryopoiesis, the regulation of TPO production, and TPO concentrations in health and disease. For neonatal thrombocytopenia, the focus is on early-onset thrombocytopenia associated with maternal diabetes, pregnancy-induced hypertension, intrauterine growth retardation, hypoxia, and sepsis. Fetal alloimmune thrombocytopenia allows insight into the biology of TPO when fetal megakaryopoiesis is chronically stimulated. In the thrombocytopenia absent radii syndrome and congenital amegakaryocytic thrombocytopenia, thrombocytopenia is caused by a disorder in the signal transduction at the c-mpl level and respectively directly on c-mpl. TPO concentrations in other inherited thrombocytopenias such as Fanconi anemia, Shwachman syndrome, Wiskott-Aldrich syndrome, and Bernard-Soulier syndrome are discussed. For acquired thrombocytopenias, data on TPO in aplastic anemia, immune thrombocytopenia, human immunodeficiency virus infection, and liver disease are given. Possible indications for a treatment with recombinant TPO in childhood are discussed, but the criteria to identify patients who would benefit need detailed evaluation.  相似文献   
59.
Kim  D; Porter  DH; Siegel  JB; Simon  M 《Radiology》1989,172(3):721-723
Various complications have been reported after insertion of the Greenfield filter. This report describes an unusual complication after suprarenal placement of this filter: spreading of the filter struts, with perforation of the inferior vena cava, and penetration of the aorta and a vertebral body, followed by fracture of one of the struts.  相似文献   
60.
The predictive value of three parameters (amniotic fluid insulin and C-peptide, and HbA1) in prognosticating major neonatal symptomatology was investigated in 57 pregnancies of diabetic women. The prediction of a healthy neonate can be achieved with a 90% accuracy by measurement of the amniotic fluid insulin alone. The correct prognosis for a child with major neonatal problems due to maternal diabetes can be made with 70% certainty using the same method. All other parameters can be judged less valuable based on our results. By using more than one of those parameters mentioned, the prediction of a healthy child can be made more correctly with a certainty of almost 100%. The accuracy in predicting a child with major symptoms cannot be increased any further.  相似文献   
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