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991.
PURPOSE: Many academic medical centers (i.e., teaching hospitals) have established primary care networks for not only assuring a referral base but also for educating students in the primary care setting. Such networks generally are not profitable when analyzed on an individual facility basis. However, revenues generated at the medical center in terms of inpatient admissions, laboratory testing etc., usually are much larger than generated on site. In this study, the downstream revenue from 18 practice sites was evaluated at The Ohio State University Medical Center. METHOD: Revenues in fiscal year July 1, 2003, to June 30, 2004, were broken down into four streams, including inpatient and outpatient charges and collections for both network and specialist physicians. A fifth stream evaluated specialist professional fees. The authors developed a novel conservative weighting system to capture the concept that not all revenues generated from network patients were actually dependent on the use of the network. RESULTS: Findings included that the downstream direct contribution margin of US dollars 14 million just from the admissions and outpatient tests and procedures directly generated by network physicians alone was nearly twice the US dollars 8.3 million network operating loss. The total downstream net revenue of nearly US dollars 115 million was more than 6 times the US dollars 18.9 million net revenue to the network. The downstream direct contribution margin of US dollars 52 million was 6.3 times the network loss. Total downstream gross revenue (charges) to the medical center was over US dollars 250 million and over US dollars 300 million when the specialist gross revenues were included. CONCLUSIONS: This study demonstrates that a primary care network can generate significant financial support for an academic medical center.  相似文献   
992.
The intent of ethics is to establish a set of standards that will provide a framework to modify, regulate, and possibly enhance moral behaviour. Eleven focus groups were conducted with physicians from six culturally distinct countries to explore their perception of formalized, written ethical guidelines (i.e., codes of ethics, credos, value and mission statements) that attempt to direct their ethical practice. Six themes emerged from the data: lack of awareness, no impact, marginal impact, other codes or value statements supersede, personal codes or values dictate, and ethical guidelines are useful. Overall, codes were valued only when they were congruent with existing personal morality. The findings suggest the need to re-evaluate the purpose, content, and delivery of codes for them to improve their function in promoting ethical conduct.  相似文献   
993.
The (R)-enantiomer of racemic albuterol produces bronchodilation, whereas the (S)-enantiomer may increase airway reactivity. After oral or intravenous administration of racemic albuterol, the (R)- enantiomer is metabolized several times faster than the (S)-enantiomer; however, enantiomer disposition after inhaling racemic albuterol with a metered-dose inhaler (MDI) is not known. Accordingly, 10 healthy subjects inhaled racemic albuterol with a MDI alone and with a MDI and holding chamber. We measured plasma levels of unchanged (R)- and (S)-albuterol before and up to 4 h after inhalation of racemic albuterol, and determined the unchanged R/S ratio in urine before and at 0.5, 4, 8, and 24 h later. The disposition of albuterol's enantiomers with a MDI and holding chamber was similar to that with a MDI alone. The area under the curve (AUC) of the plasma levels over time was significantly lower for the (S)- than for the (R)-enantiomer-395.5 +/- 141.0 (SE) versus 882.7 +/- 126.4 ng. ml(-)(1). min (p < 0.05)-indicating preferential retention of (S)-albuterol in the lung. The R/S ratio in urine at 0. 5 h after albuterol was > 1, reflecting the higher plasma level of the (R)-enantiomer. In conclusion, preferential retention of the (S)- compared with the (R)-enantiomer in the lung could lead to accumulation of the (S)-enantiomer after long-term use of racemic albuterol.  相似文献   
994.
995.
Circadian rhythm sleep disorders are characterized by a desynchronization between the timing of the intrinsic circadian clock and the extrinsic light-dark and social/activity cycles resulting in symptoms of excessive sleepiness and insomnia. This article explores the six recognized circadian rhythm sleep disorders: delayed sleep phase syndrome, advanced sleep phase syndrome, non-24-hour sleep-wake syndrome, irregular sleep-wake pattern, shift work sleep syndrome, and time zone change syndrome. Additionally discussed are the therapeutic roles of synchronizing agents, such as light and melatonin.  相似文献   
996.
BACKGROUND: There is uncertainty about which children with cough are most and least likely to experience complications. AIM: To derive a clinical prediction rule for complications in pre-school children presenting to primary care with acute cough. Design of study: Prospective cohort study. SETTING: Eight general practices in Leicestershire, United Kingdom. METHOD: Pre-school children with cough for < or =28 days and without asthma were recruited. Sociodemographic, clinical history, and examination data were collected and univariable logistic regression used to explore the associations with complications. These were defined as any new symptom, sign or diagnosis identified by a primary care clinician at a parent initiated reconsultation, or hospital admission, before cough resolution. Those factors with stronger relationships (P< 0.2) were then modelled using multivariable logistic regression to identify the factors independently associated with complications. RESULTS: The pre-test probability of complications was 10%. On univariable analysis, fever (odds ratio [OR] = 4.86; 95% confidence interval [CI] = 1.74 to 13.6), chest signs (OR = 2.72; CI = 1.06 to 6.96), and tachypnoea (OR = 3.80; CI = 1.22 to 11.8) were associated with complications. On multivariable analysis, only fever (OR = 5.56; CI = 1.75 to 17.6) and chest signs (OR = 2.88; CI = 1.02 to 8.05) were independently associated with complications. These ORs translate into post-test probabilities of complications of 6% for children with neither fever nor chest signs, 18% for children with chest signs, 28% for children with fever, and 40% for children with fever and chest signs. CONCLUSIONS: If validated, this clinical prediction rule could be used to individualise the management of acute cough in pre-school children.  相似文献   
997.
998.
The use of tympanic thermometry is attractive in primary care, but a recent systematic review highlighted the paucity of data comparing tympanic thermometry with conventional methods. We report a study of 94 preschool children presenting to primary care in the United Kingdom (UK) with acute cough in whom tympanic infrared and axillary mercury thermometry are compared. Infrared thermometry showed poor agreement, poor sensitivity and high specificity. Infrared thermometry is too insensitive to be used as a screening test for fever, but when fever is already suspected, for example by touch, it may be useful as a 'rule in' test.  相似文献   
999.
Human immunodeficiency virus type 1(HIV-1) induces extensive immune cell alterations which can be detected by changes both in serum levels of soluble immune activation products and in several lymphoid phenotypic markers. The current studies were conducted in 70 HIV-1 seropositive subjects to determine whether changes among four important serum immune activation markers (neopterin, beta-2 microglobulin, soluble CD8, and soluble IL-2 receptor) and seven lymphoid phenotypic markers (CD38, HLA-DR, CD57, CD11b, CD45RA, leu8, and CD71) reflect similar or disparate aspects of immune pathology. On the basis of correlation coefficient calculation, four groups of related markers (Fig. 1) were identified: Group A, sIL-2R was related to group B where serum neopterin, beta 2M, sCD8 levels, and lymphocyte CD38 antigen expression correlated closely. Loss of CD45RA or Leu 8 antigens in group C correlated with group B and D markers increase. HLA-D in group D was a more distantly related immune activation marker. Phenotypic markers CD57, CD11b, and CD71 did not correlate with the immune activation processes reflected by the serum and phenotypic marker groups A-D. Correlations between serum and certain lymphoid phenotypic markers were generally stronger later in HIV-1 infection when CD4 levels were less than 500/mm3. This study provides information for selecting markers for investigating immune changes in HIV-1 infection and immune-related diseases. Many serum and lymphoid phenotypic markers reflect related aspects of immune dysregulation. However, some markers can indicate different aspects of disease.  相似文献   
1000.
The prognosis of Hodgkin's disease in older adults   总被引:2,自引:0,他引:2  
This investigation was undertaken to assess the apparent poor survival of older patients with Hodgkin's disease. The clinical course of Hodgkin's disease in 136 patients, 60 to 79 years of age, was compared with that of 223 patients, 40 to 59 years of age. The patients registered from November 1977 through December 1983 had not been previously treated, and were treated at eight cancer centers. When the prognosis of all patients was examined by age, a definite change in the pattern of survival first appeared in the 60- to 69-year-old cohort. The entire older group (60 to 79 years) experienced twice the risk of dying from Hodgkin's disease and four times the risk of dying from other causes than did the younger group. In both groups, stage of disease was the strongest factor in predicting adjusted survival. Delay in treatment and advanced stage at presentation were not characteristic of Hodgkin's disease in older patients as has been postulated. Older patients responded to therapy with a similar complete remission rate (84% v 88% in the younger group, P = .24). From this study, we conclude that (1) Hodgkin's disease in the older adult does not have a different natural history, its major risk factors are similar to those known in other age groups, and thus should be amenable to existing therapeutic approaches; and (2) the prognosis of older patients with Hodgkin's disease has been obscured in previous studies by the inclusion of deaths due to other causes in survival estimates.  相似文献   
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