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21.
COHEN M.; PARRY G.; ADAMS P.C.; XIONG J.; CHAMBERLAIN D.; WIECZOREK I.; FOX K. A. A.; KRONMAL R.; FUSTER V.; THE ANTITHROMBOTIC THERAPY IN ACUTE CORONARY SYNDROMES RESEARCH GROUP 《European heart journal》1994,15(9):1196-1203
The aim of this trial was to compare the efficacy of combinationantithrombotic therapy with a prostacyclin-sparing aspirin plusanticoagulation versus conventional aspirin plus anticoagulation,when added to antianginal therapy, in patients with unstableangina or non-Q wave myocardial infarction already being treatedwith aspirin. In a double-blind (for the aspirin) study, 144prior aspirin users were randomized; 72 patients received controiled-release,prostacyclin-sparing aspirin 75 mg daily plus anticoagulation(intravenous heparin followed by warfarin to maintain the internationalnormalized ratio at 23), and 72 patients received conventionalaspirin 75 mg daily plus the same anticoagulation. Controlled-releaseaspirin was formulated to preserve endothelial cell prostacyclinsynthesis. Trial therapy was begun by 13.2 ± 12.3 h ofqualifying pain, and continued for 12 weeks. The frequency of recurrent angina with electrocardiographicchanges, myocardial infarction, or death, was analysed by intentionto treat. At 12 weeks, events were 相似文献
22.
THEODORE COHEN M.D. F.A.C.G. ROBERT B. PFEFFER M.D. QUENTIN VALENSI M.D. 《The American journal of gastroenterology》1974,62(2):151-154
A 39-year old white female with a 19-year history of chronic ulcerative colitis was admitted to the hospital with fulminating disease and toxic megacolon requiring total colectomy.
The appendicial changes were most unusual. The pathological changes were typical of those seen in ulcerative colitis, namely, mucosal ulceration and crypt abscess formation ("ulcerative appendicitis"). Furthermore, these changes occurred as a skip lesion since the cecum and ascending colon were both free of disease. 相似文献
The appendicial changes were most unusual. The pathological changes were typical of those seen in ulcerative colitis, namely, mucosal ulceration and crypt abscess formation ("ulcerative appendicitis"). Furthermore, these changes occurred as a skip lesion since the cecum and ascending colon were both free of disease. 相似文献
23.
Michael L. ALOSCO Andreana BENITEZ John GUNSTAD Mary Beth SPITZNAGEL Jeanne M. MCCAFFERY John E. MCGEARY Athena POPPAS Robert H. PAUL Lawrence H. SWEET Ronald A. COHEN 《Psychogeriatrics》2013,13(1):35-40
Background: Much attention has been paid to the prevalence and predisposition of the fat mass and obesity‐associated (FTO) gene to obesity, although only a few studies have characterized the extent to which this affects cognitive function. This study examined differences between risk allele carriers (i.e. FTO‐AC/AA) and non‐carriers (i.e. FTO‐CC) on indices of attention/executive function/psychomotor speed, memory, language, and visual‐spatial ability in a sample of older patients with cardiovascular disease. Methods: We recruited 120 older adults from an outpatient cardiology clinic who underwent blood draw and completed neuropsychological testing. Participants were classified into two groups: one for those who were homozygous for the non‐risk‐conferring allele (i.e. FTO‐CC) (n= 49) and the other for those who had at least one copy of the obesity risk‐conferring A allele (i.e. FTO‐AC/AA) (n= 71). Results: Mancova analyses adjusting for age and years of education revealed the FTO‐AC/AA group performed significantly worse on indices of memory (λ= 0.94, F(2, 115) = 3.58, P= 0.03, partial η2= 0.06). Follow‐up tests revealed a significant effect for the FTO‐AC/AA group, relative to the non‐carrier group, on encoding (i.e. California Verbal Learning Test Total Learning) and California Verbal Learning Test long‐delay free recall (P < 0.05). No such differences between FTO carriers and non‐carriers emerged on tests of attention/executive function/psychomotor speed, language, or visual‐spatial ability (P > 0.05 for all). Conclusions: These findings suggest that the FTO risk allele is associated with reduced memory performance, particularly on aspects of memory encoding and delayed recall. To elucidate underlying mechanisms, these findings will need to be replicated in larger samples that utilize neuroimaging. 相似文献
24.
TODD J. COHEN ENRICO P. VELTRI J. JOHN LATTUCA MORTON M. MOWER 《Pacing and clinical electrophysiology : PACE》1988,11(11):1522-1528
The hemodynamic responses to rapid atrial and ventricular pacing were examined in 10 closed-chest anesthetized dogs in an attempt to distinguish hemodynamically stable from unstable tachycardias. Pressure monitoring catheters were placed in the femoral artery, right atrium, and right ventricle to measure mean arterial pressure, mean right atrial pressure, and mean right ventricular pressure at baseline heart rate and after rapid high right atrial and right ventricular apex pacing. Pressures recorded during rapid pacing (average of the pressures at 30 and 60 seconds of pacing) at pacing rates of 180, 250, and 280/minute were compared to those recorded initially at baseline heart rates. Rapid right ventricular apex pacing resulted in significant increases in mean right atrial pressure (from 6 ± 1 mmHg (mean ± standard error) to 12 ± 1 mmHg, a 100% increase, P < 0.001) and mean right ventricular pressure (from 11 ±1 mmHg to 16 ± 1 mmHg, a 45% increase, p < 0.02) with marked hemodynamic compromise (mean arterial pressure decreased from 85 ± 6 mmHg to 50 ± 6 mmHg, a 41% decrease, P < 0.01). These parameters remained stable (no statistically significant difference from baseline) during high right atrial pacing. In half of the dogs high right atrial pacing at rates 250 resulted in atrioventricular Wenckebach. Thus, it is concluded that mean right atrial pressure and mean right ventricular pressure may be useful in distinguishing hemodynamically significant tachycardias, and in the future design of antitachycardia devices. 相似文献
25.
Estimating impossible curves using NONMEM 总被引:3,自引:11,他引:3
1 On fitting model equations to experimental data, the situation may arise that individual subjects provide insufficient information to obtain adequate parameter estimates due to the fact that not all aspects are exhibited by all subjects or that the models are simply too complex. This may be solved by applying nonlinear mixed effect modelling to the data, which integrates the information provided by different subjects.
2 We aim to provide insight into the methodology and its use in these situations, illustrated by three examples: determination of pharmacokinetics in a rising dose design, where the lower doses provide insufficient information (due to assay limitations) to estimate terminal half-life; determination of the kinetics of the low molecular weight heparin enoxaparine (Clexane® ) using anti-Xa activity, effectively dealing with lingering low/basal activity; simultaneous estimation of the pharmacokinetics and pharmacodynamics of the low molecular weight heparin dalteparine (Fragmin® ) after subcutaneous and intravenous administration. 相似文献
2 We aim to provide insight into the methodology and its use in these situations, illustrated by three examples: determination of pharmacokinetics in a rising dose design, where the lower doses provide insufficient information (due to assay limitations) to estimate terminal half-life; determination of the kinetics of the low molecular weight heparin enoxaparine (Clexane
26.
ARIELA HIDAS JOEL COHEN MAURIT BEERI JOSEPH SHAPIRA DORON STEINBERG MOTI MOSKOVITZ 《International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children》2010,20(3):179-185
International Journal of Paediatric Dentistry 2010; 20: 179–185 Objectives. This study examined caries level, amount of calculus, and oral microbial environment in gastrostomy tube (GT)‐fed children compared with healthy children and children with disabilities orally fed (PO). Study design. The study group consisted of 12 GT‐fed children and the two control groups consisted of 16 children with disabilities orally fed and 17 healthy children. DMF‐T/dmf‐t index, calculus index, Mutans Streptococci (MS), Lactobacilli (LB) levels and salivary buffer capacity were examined. Results. DMF‐T/dmf‐t index was significantly lower in the tube‐fed group. Calculus index was highest in the tube‐fed group. MS and LB levels were the lowest in the tube‐fed children. Correlation was found between MS and DMF‐T/dmf‐t. Conclusions. Tube‐fed children demonstrated significantly higher calculus levels and less caries, MS, and LB levels then healthy children or children with disabilities eating PO. 相似文献
27.
DANIEL J. COHEN AMY BEGLEY JENNIE J. ALMAN DAVID J. CASHMERE REGINA N. PIETRONE ROBERT J. SERES ANNE GERMAIN 《Journal of sleep research》2013,22(1):76-82
Sleep disturbances are a hallmark feature of post‐traumatic stress disorder (PTSD), and associated with poor clinical outcomes. Few studies have examined sleep quantitative electroencephalography (qEEG), a technique able to detect subtle differences that polysomnography does not capture. We hypothesized that greater high‐frequency qEEG would reflect ‘hyperarousal’ in combat veterans with PTSD (n = 16) compared to veterans without PTSD (n = 13). EEG power in traditional EEG frequency bands was computed for artifact‐free sleep epochs across an entire night. Correlations were performed between qEEG and ratings of PTSD symptoms and combat exposure. The groups did not differ significantly in whole‐night qEEG measures for either rapid eye movement (REM) or non‐REM (NREM) sleep. Non‐significant medium effect sizes suggest less REM beta (opposite to our hypothesis), less REM and NREM sigma and more NREM gamma in combat veterans with PTSD. Positive correlations were found between combat exposure and NREM beta (PTSD group only), and REM and NREM sigma (non‐PTSD group only). Results did not support global hyperarousal in PTSD as indexed by increased beta qEEG activity. The correlation of sigma activity with combat exposure in those without PTSD and the non‐significant trend towards less sigma activity during both REM and NREM sleep in combat veterans with PTSD suggests that differential information processing during sleep may characterize combat‐exposed military veterans with and without PTSD. 相似文献
28.
CONTRASTING EFFECTS OF SUBCUTANEOUS PULSATILE GnRH THERAPY IN CONGENITAL ADRENAL HYPOPLASIA AND KALLMANN''S SYNDROME 总被引:1,自引:0,他引:1
D. GORDON H. N. COHEN G. H. BEASTALL I. D. HAY J. A. THOMSON 《Clinical endocrinology》1984,21(6):597-603
A patient with congenital adrenal hypoplasia (AH) and hypogonadotrophic hypogonadism was treated with pulsatile subcutaneous GnRH therapy for 16 weeks in an attempt to induce puberty. No rise in serum LH or FSH concentrations occurred despite increasing doses of GnRH (2.8 micrograms/pulse-22.4 micrograms/pulse). In contrast a similar programme of therapy successfully initiated the biochemical changes of puberty in a patient with Kallmann's syndrome. Both patients before therapy had low basal serum LH and FSH concentrations with blunted LH and FSH responses to GnRH stimulation. After 1 week, serum LH and FSH rose into the normal adult range in the patient with Kallmann's syndrome. This study fails to confirm a previous report which suggested that intermittent low dose GnRH therapy may be of value in inducing puberty in AH. The reasons for the difference of pituitary responsiveness to GnRH in AH and Kallmann's syndrome are unclear at present. 相似文献
29.
BARRY WIENER MSN C CCRN RN SOOSAN CHACKO BS RN TAMMY R. BROWN MSN ACNP-C RN STANLEY G. CRON MSPH MARLENE Z. COHEN PhD FAAN RN 《Journal of nursing management》2009,17(5):532-538
Aim To identify nurses' priorities for topics and issues to be addressed by a developing nursing research program at a county hospital.
Background Delphi surveys have been effective at other hospitals to identify research priorities of nurses.
Methods A Delphi survey was performed in two rounds. Questionnaires were distributed to all 415 nurses who worked at the hospital.
Results A total of 274 nurses returned the Round I questionnaire (response rate, 66%), and 249 returned the Round II questionnaire (response rate, 60%).
Conclusions The Delphi survey was successfully used to identify nurses' research priorities at a county hospital. A total of 39 topics were identified from content analysis of research areas described by nurses. Factor analysis revealed three factors: work environment, newborn issues and effects of leadership.
Implications for nursing management The Delphi survey is a useful way to begin a program of research. Nurses who have a successful experience with research are more likely to become further involved in research, which will allow them to more effectively participate in decision making and improving the work environment. In addition, items were identified that needed to be addressed by nursing managers. 相似文献
Background Delphi surveys have been effective at other hospitals to identify research priorities of nurses.
Methods A Delphi survey was performed in two rounds. Questionnaires were distributed to all 415 nurses who worked at the hospital.
Results A total of 274 nurses returned the Round I questionnaire (response rate, 66%), and 249 returned the Round II questionnaire (response rate, 60%).
Conclusions The Delphi survey was successfully used to identify nurses' research priorities at a county hospital. A total of 39 topics were identified from content analysis of research areas described by nurses. Factor analysis revealed three factors: work environment, newborn issues and effects of leadership.
Implications for nursing management The Delphi survey is a useful way to begin a program of research. Nurses who have a successful experience with research are more likely to become further involved in research, which will allow them to more effectively participate in decision making and improving the work environment. In addition, items were identified that needed to be addressed by nursing managers. 相似文献
30.