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21.
Distributed computing can be applied to CT or MRI scanner image acquisition, printing, and archiving by interfacing the scanner with a computer network. Also on the network must be a computer workstation that has image management software to capture the images sent over the network by the scanner. This software must also allow the radiology staff to print and archive the images. Several benefits are realized by this network configuration. First, the scanner console is solely used for scanning patients; delays are not encountered because the console is being used for printing and archiving images. Also, the workstation printing software can be developed so that useful features not available at the scanner console can be incorporated. Finally, sophisticated archiving strategies can be implemented at the workstation. We have developed a network image management station at the Fox Chase Cancer Center using a reduced instruction set computer (RISC) workstation. Hardware and software is utilized to convert all scanner image data to the American College of Radiology-National Electrical Manufacturers Association format. All workstation software is developed using the open X-Windows standard. Digital audio tape is used for image archiving. 相似文献
22.
Monovision correction for diplopia 总被引:1,自引:0,他引:1
R London 《Journal of the American Optometric Association》1987,58(7):568-570
Acquired, incomitant strabismus frequently results in diplopia. Affected patients complain of chronic annoyance and frustration with the false image. Therapy has usually been aimed at either re-establishing binocularity by using prisms or vision training, or by eliminating one image through occlusion. An alternative approach is to allow each eye its own "domain," one eye corrected for distance vision and the other for near vision. This alternative may eliminate the competitive, unfusible images and yet maintain visual function in each eye. 相似文献
23.
A E George M J de Leon C I Gentes J Miller E London G N Budzilovich S Ferris N Chase 《AJNR. American journal of neuroradiology》1986,7(4):561-566
Central white matter lucencies are commonly seen in CT scans of elderly patients. Reports in the literature have implicated demyelination due to subcortical vascular disease (Binswanger disease) as the cause of these lucencies. Binswanger disease, however, is thought to be rare. Because of this apparent discrepancy we decided to determine the incidence and to attempt to define the clinical significance of the CT white-matter changes in a study population at New York University Medical Center. The studies of 275 normal and demented subjects, ages 23 to 85 years, were reviewed. All subjects received neurologic, psychiatric, and medical evaluation, formal psychometric evaluation of their cognitive status, and a CT scan. CT scans were evaluated for the presence and severity of white-matter changes (leukoencephalopathy). The incidence and severity of white-matter changes increased significantly with age (p less than 0.01). Leukoencephalopathy was consistently more common in demented patients than in normal subjects, but the difference was not statistically significant, and the severity of the leukoencephalopathy was not related to the severity of dementia (p less than 0.05). Five patients (ages 74 to 95 years) with a clinical diagnosis of Alzheimer disease who had CT evidence of lucencies were examined at autopsy. Neuropathology demonstrated extensive changes of Alzheimer disease in one brain and mild-to-moderate changes in the other four brains; areas of white-matter rarefaction were present in all brains, with microscopic evidence of arteriolar hyalinization. This study demonstrates that leukoencephalopathy is strongly related to the aging process and is seen in both "normal" and cognitively impaired individuals who have no other evidence of vascular disease.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
24.
This study was designed to determine the effects of four well-characterized dietary brans on large bowel tumorigenesis induced in mice with 1,2-dimethylhydrazine (DMH). Eight-week-old barrier-derived male Balb/c mice were fed a semisynthetic diet with 20% bran added (either corn, soybean, soft winter wheat, or hard spring wheat) or a no-fiber-added control diet. Half of each group was given DMH (20 mg/kg body weight/week, subcutaneously for 10 weeks) beginning at 11 weeks of age. Surviving mice were killed 40 weeks after the first DMH injection. Tumors were not found in mice not subjected to DMH. In DMH-treated mice, tumors were found almost exclusively in the distal colon. Tumor incidences were as follows: controls, 11%; soybean group, 44%; soft winter wheat group, 48%; hard spring wheat group, 58%; and corn group, 72%. Tumors per tumor-bearing mouse ranged from 1.4 to 1.6, except in the corn group, which had 2.1. A positive correlation was found between percentage of neutral detergent fiber in the brans and tumor incidences but not between the individual components of cellulose, hemicellulose, or lignin. The enhancement of DMH-induced large bowel tumorigenesis by all four bran types may reflect a species and/or mouse strain effect that is bran-source related. These data emphasize the importance of using well-defined bran in all "fiber" studies. 相似文献
25.
Morphine-induced metabolic changes in human brain. Studies with positron emission tomography and [fluorine 18]fluorodeoxyglucose 总被引:1,自引:0,他引:1
E D London E P Broussolle J M Links D F Wong N G Cascella R F Dannals M Sano R Herning F R Snyder L R Rippetoe 《Archives of general psychiatry》1990,47(1):73-81
Morphine sulfate effects (30 mg, intramuscularly) on cerebral glucose utilization and subjective self-reports were examined in 12 polydrug abusers by positron emission tomography and [fluorine 18]fluorodeoxyglucose in a double-blind placebo-controlled crossover study. During testing, subjects sat with eyes covered, listening to white noise and "beep" prompts. Morphine significantly reduced glucose utilization by 10% in whole brain and by about 5% to 15% in telencephalic areas and the cerebellar cortex, assuming no contribution of hypercapnia. When the contribution of PaCO2 (45 minutes after morphine was administered) was partialled out, significant morphine-induced reductions persisted in whole brain and six cortical areas. Irrespective of morphine, left-greater-than-right asymmetry occurred in the temporal cortex, and an interaction between hemisphere and drug was noted in the postcentral gyrus. In most cases, effects on glucose utilization were not significantly related to measures of euphoria. 相似文献
26.
4-Phenyl-1-(4-phenylbutyl)piperidine(4-PPBP) is a very potent ligand for σ (Sigma) receptors. The present study was undertaken to evaluate [3H]4-PPBPas a radioligand for in vivo labeling of cerebral σ receptors. After intravenous administration of [3H]4-PPBP to mice, there is high uptake of radioactivity in the brain. The regional distribution of radioactivity in the brain 2 h after intravenous injection of [3H]4-PPBP parallels the in vitro binding of the radioligand in rat brain (pons/medulla > cerebellum ≥ prefrontal cortex ≥ parietal cortex > hypothalamus > olfactory tubercle ≥ thalamus > hippocampus > striatum). Pretreatment with haloperidol (2 mg/kg) significantly decreases the radioactivity measured in the brain 30–120 min after injection of [3H]4-PPBP. Pretreatment with unlabeled 4-PPBP or ifenprodil also significantly decreases radioactivity in the brain 2 h after injection of [3H]4-PPBP, in a dosedependent manner. The in vivo binding of [3H]4-PPBP in the brain also is significantly inhibited by SL 82.0715, BMY 14802, 1,3-di-o-tolylguanidine (DTG), and (+)-enantiomers of pentazocine, SKF 10,047, and 3-PPP, but not by the corresponding (?)-enantiomers, consistent with stereoselectivity of inhibition obtained in in vitro binding studies. In contrast, pretreatment with dizocilpine and spiperone does not inhibit in vivo binding of [3H]4-PPBP. The results indicate that [3H]4-PPBP would be a suitable radioligand for in vivo labeling of σ receptors in brain. © 1995 Wiley-Liss, Inc. 1 This article is a US Government work and, as such, is in the public domain in the United States of America . 相似文献
27.
Comparison of 7-nitroindazole with other nitric oxide synthase inhibitors as attenuators of opioid withdrawal 总被引:3,自引:0,他引:3
D. Bruce Vaupel Alane S. Kimes Edythe D. London Edythe D. London 《Psychopharmacology》1995,118(4):361-368
Previously, we demonstrated that two nonselective inhibitors of nitric oxide synthase (NOS),l-N
G-nitroarginine (l-NNA) andl-N
G-nitroarginine methyl ester (l-NAME), reduced some signs of morphine withdrawal in rats. The present work extended these studies to include 7-nitroindazole (7-NI), an inhibitor specific for cerebral NOS, andN(5)-(1-iminoethyl)-l-ornithine (l-NIO), a potent inhibitor of endothelial NOS. Behavioral effects of these four NOS inhibitors and clonidine, an
2-adrenoceptor, agonist, on morphine withdrawal in rats were assessed. Rats received one 75-mg morphine pellet subcutaneously (SC). Three days later, NOS inhibitors were administered IP 1 h before withdrawal was precipitated with naloxone (0.5 mg/kg, SC) and scored. 7-NI,l-NIO,l-NAME andl-NNA produced dose-related decreases in weight loss, diarrhea, wet dog shakes and grooming. 7-NI also reduced mastication, salivation and genital effects. Clonidine produced effects similar to 7-NI. In awake, morphine-naive and morphine-dependent rats not subjected to withdrawal, 7-NI was the only NOS inhibitor that did not increase blood pressure. Because 7-NI attenuated more signs of opioid withdrawal thanl-NNA,l-NAME orl-NIO without causing hypertension, 7-NI appears to warrant further testing as a potential candidate for human use.Abstracts were presented at the annual meetings of the College on Problems of Drug Dependence, West Palm Beach, Fla., 18–23, June 1994; International Narcotics Research Conference, North Falmouth, Cape Cod, Mass., 16–21, July 1994; and a Satellite Symposium to IUPHAR, Montreal, Canada, 22–24, July 1994. 相似文献
28.
This study investigated the effect of education and audit on the identification and management of medical inpatients with excessive alcohol consumptions by use of a cross-sectional survey of medical and nursing notes, compared with historical controls. We report the proportion of medical and nursing notes containing qualitative and quantitative drinking histories, the use of the CAGE questionnaire, and notification of alcohol consumption in discharge summaries. A total of 1,979 out of 2,680 (74%) notes of eligible patients were examined. The number of medical notes containing quantitative alcohol histories rose from 175/792 (22%) among historical controls, to 242/690 (35%) after training of junior medical and nursing staff, and to 241/497 (48%) after feedback of results in a clinical audit meeting. The number of medical notes with no recorded alcohol history changed from 309/792 (39%) to 287/690 (42%) to 152/497 (31%), respectively (chi 2 for trend = 97.2, p < 0.0001). The number of nursing notes containing quantified alcohol histories rose from 31/792 (4%) among historical controls, to 123/690 (18%) after training, and to 237/497 (48%) after feedback of results in a clinical audit meeting. The number of nursing notes with no recorded alcohol history fell from 309/792 (90%), to 512/690 (74%), to 205/497 (41%) respectively (chi 2 for trend = 353.7, p < 0.0001). The proportion of patients found to be drinking excessively rose from 40/792 (5.1%) to 57/690 (8.3%) to 45/497 (9.1%) (chi 2 for trend = 8.25, p = 0.004). There was little worthwhile improvement in use of the CAGE questionnaire and in discharge summaries. Education and audit are effective ways of improving the identification of excessive drinkers by both junior doctors and nurses alike. Other aspects of management are less responsive. 相似文献
29.
Pavelchak N Church L Roerig S London M Welles W Casey G 《Applied occupational and environmental hygiene》1999,14(1):34-38
Exposure to silo gas is a recognized agricultural hazard. Silo gas produced from corn fermentation may consist of oxides of nitrogen and carbon dioxide. The presence of potentially lethal concentrations of nitrogen dioxide (NO2) within vertical silos has been well documented. The risk of silo gas exposure from other silage storage methodologies--including horizontal "ag-bags" and concrete bunkers--has been less well characterized. A dry growing season is known to be a factor for elevating nitrate levels in corn plants and can result in increased NO2 production. Farms in the northeastern United States faced drought conditions during the 1995 growing season. The New York State (NYS) Department of Health (DOH) and the New York Center for Agricultural Medicine and Health (NYCAMH) investigated four exposure incidents involving six farmworkers during September/October 1995. Four of these workers were hospitalized for multiple days, with two workers receiving treatment in intensive care units. The remaining two workers were treated in hospital emergency departments; one refused admission and left against medical advice. We monitored NO2 levels from "ag-bags" at several New York farms. For four days, outdoor concentrations of NO2 at one site remained in excess of the National Institute for Occupational Safety and Health's (NIOSH) immediately dangerous to life and health value (IDLH) of 20 ppm. As a result of the clinical and industrial hygiene data, and the growing season's abnormal weather conditions, DOH and NYCAMH issued statewide health hazard alerts and conducted educational activities to warn farmers and their families. The findings of this study reinforce the potential hazards associated with silo gas exposure and identify the use of ag-bags as a relatively new avenue for significant worker exposure. 相似文献
30.