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51.
Covalently crosslinked liquid crystalline networks with elastic properties were prepared in isotropic solution from linear liquid crystalline polymers. As linear precursors for the networks were used: (i) polymers with the mesogenic groups in the side groups (polyacrylates and polymethacrylates), (ii) polymers with the mesogenic groups in the main chain (polymalonates) and (iii) polymers with the mesogenic groups in main chain and side groups (“combined liquid crystalline polymers”). In all crosslinked polymers the liquid crystalline phases of the linear polymers are retained. For low degrees of crosslinking (≤2 mol-%) the phase transition temperatures remain nearly unchanged. These elastomers are very soft above Tg and can be easily stretched for more than 100%. For higher degrees of crosslinking the phase transition temperatures are reduced. 相似文献
52.
Fürstenau Daniel Haneke Hannah Spies Claudia Walz Tim Schewina Kai Höft Moritz Mörgeli Rudolf Balzer Felix 《Zeitschrift fur Gesundheitswissenschaften》2022,30(1):99-110
Journal of Public Health - The purpose of this paper is to investigate the implementation of value-based care principles in the context of frailty in the perioperative process, highlighting the... 相似文献
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55.
Quality-of-Life Outcome After Laparoscopic Adjustable Gastric Banding for Morbid Obesity 总被引:3,自引:0,他引:3
Background: The definition of success and failure of a bariatric procedure should include weight loss as well as improvement
of comorbidity and quality-of-life (QoL) assessment. QoL measures changes in physical, functional, mental, and social health
in order to evaluate benefits of new programs and interventions. Material and Methods: From April 1995 until March 1999, 287
patients underwent laparoscopic adjustable silicone gastric banding (LASGB) at Northwest Hospital Frankfurt a.M. (Germany).
In this study, 100 of 287 patients (preoperative mean BMI 48.3 kg/m2; mean age 35.2 years) with a follow-up >18 month were evaluated. All patients underwent anonymous questionnaire (26 questions
with a maximum score of 60) about different aspects of QoL outcome after LSAGB. Results: In this study, 4 of 100 patients
refused to give an answer to the QoL questions. Therefore 96 patients were evaluated. The QoL auto-evaluation of the patients
shows that QoL generally improved after surgery in 92%. Using the scoring system, 44% of patients have excellent, 52% good,
and only 4% bad results. The 4 patients who refused had to be classified as failure. General acceptance of LSAGB is wide,
but gastrointestinal side effects are recognizable in more than 78% of operated patients. Successful weight loss is followed
by an improvement of comorbidities. Conclusions: Safe, effective bariatric procedures increase the quality of life in morbidly
obese patients markedly. Bariatric surgeons are committed to support and help their patients until they reach a new quality
of life after obesity surgery. 相似文献
56.
This study investigated Subjective Quality of Life (SQOL) in 42 women with depression, 70 women with alcoholism, and 73 women with schizophrenia within 3 weeks after hospital admission. Twenty-eight of the depressive patients were re-examined after 6 months. SQOL was assessed using the German version of the Lancashire Quality of Life Profile. On average, depressive women expressed dissatisfaction with life as a whole and with 4 out of 8 life domains, and had a lower SQOL than the other two diagnostic groups. Differences remain statistically significant when the influence of age and anxiety/depression is controlled for. SQOL in depressive women improved significantly within the follow up period. Positive SQOL change was moderately correlated with an improvement of depressive symptoms. The results indicate that depressive women after hospital admission express an unusually low SQOL, which seems to have some diagnostic specificity and improves over time. Changes in depressive symptoms do not fully explain SQOL changes. 相似文献
57.
Penetration of ciprofloxacin, norfloxacin and ofloxacin into the aqueous humor using different topical application modes 总被引:3,自引:0,他引:3
R. Beck Jan van Keyserlingk Ulrike Fischer Rudolf Guthoff Bernd Drewelow 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1999,237(2):89-92
· Background: A prospective study was undertaken to determine the transcorneal penetration of three topically applied fluoroquinolones
into aqueous humor. · Methods: Cataract patients (n=224) preoperatively received topically applied gyrase inhibitors (0.3% ciprofloxacin, 0.3% norfloxacin, 0.3% ofloxacin) in
two different application modes. In application mode I, patients received on the day before operation 3×1 eye drop at 2-h
intervals, and on the day of operation 3 drops at 1-h intervals. In application mode II, patients received 9 drops at 15-min
intervals on the day of operation only. Just before cataract surgery 50–100 μl aqueous humor was aspirated and stored at –80
°C. The HPLC method was used for measuring the concentration. · Results: The highest concentrations of all tested antibiotics
were measured after the mode of application in which one drop was given every 15 min between 06:00 and 08:00 hours before
operation. In this mode, ciprofloxacin achieved a mean aqueous level of 379.8±327.8 μg/l (range 33–1388 μg/l), norfloxacin
182.1±118.1 μg/l (range 38–480 μg/l) and ofloxacin 563.9±372.1 μg/l (range 64–1455 μg/l). These mean concentration are all
above the MIC90 of gram-negative bacteria like Proteus mirabilis and Escherichia coli. In some cases the concentrations of ciprofloxacin and ofloxacin, but never norfloxacin, reached therapeutic values above
the MIC90 of Staphylococcus aureus and Staphylococcus epidermidis · Conclusions: The mean concentration value of 0.3% ciprofloxacin and of 0.3% ofloxacin in the aqueous humor reached the MIC90 values of the frequently occurring gram-positive and gram-negative bacteria. Of the currently available topical fluoroquinolones,
ofloxacin achieved the highest aqueous humor concentration. Considering the higher antimicrobial activity of ciprofloxacin,
both ciprofloxacin and ofloxacin may be useful ophthalmic agents in antibacterial management, but they are not efficient against
Streptococcus pneumoniae and Pseudomonas aeruginosa.
Received: 8 September 1997 Revised version received: 19 March 1998 Accepted: 8 April 1998 相似文献
58.
59.
K.J. Wirth E. Klaus H.C. Englert B.A. Schölkens W. Linz 《Naunyn-Schmiedeberg's archives of pharmacology》1999,360(3):295-300
Ventricular fibrillation (VF) is a major cause of sudden cardiac death in which myocardial ischemia plays a leading role. During ischaemia activation of ATP-sensitive potassium channels (K(ATP)) occurs, leading to potassium efflux from cardiomyocytes and shortening of the action potential favoring the genesis of ventricular fibrillation. In confirmation of this concept the sulfonylurea glibenclamide, which stimulates insulin release by inhibition of pancreatic K(ATP) channels, has been shown to inhibit VF in different models of ischaemia by inhibition of myocardial K(ATP) channels. HMR 1883 (1-[15-12-(5-chloro-o-anisamido)ethyl]-methoxyphenyl]sulfonyl]-3-m ethylthiourea) was designed as a cardioselective K(ATP) channel blocker. The aim of this study was to show that with this compound it is possible to separate the antifibrillatory from the insulin-releasing effect for the treatment of patients at risk of ischaemia-induced arrhythmias and sudden death. In the present study HMR 1883 reduced VF in Sprague-Dawley rats during prolonged ischaemia and also diminished mortality and the duration of VF in a separate reperfusion experiment at 3 mg/kg and 10 mg/kg with no effect on blood glucose or insulin. Glibenclamide, which was antifibrillatory at 0.3 mg/kg and 1 mg/kg, increased plasma insulin and lowered blood glucose already at a dose as low as 0.01 mg/kg. In conclusion, based on its antifibrillatory action and the absence of significant pancreatic effects at therapeutic doses, HMR 1883 is of potential clinical utility for the prevention of severe arrhythmias in patients with ischaemic heart disease. 相似文献
60.
Thomas Dierks Stefan Barta Lothar Demisch Klaus Schmeck Ekkehart Englert Andrea Kewitz Konrad Maurer Fritz Poustka 《Psychopharmacology》1999,146(1):101-107
Rationale: The intensity dependence of the auditory evoked potentials (AEP) has been suggested to be a specific biological marker of
central serotonergic activity. Objective: While previous studies used circumstantial evidence to support this hypothesis, we manipulated (decreased) cerebral levels
of serotonin directly by using tryptophan depletion. Methods: Twelve healthy young subjects were investigated using placebo and two different amino acid mixtures in a double blind cross
over design on three different occasions. AEPs recorded during tryptophan depletion were analyzed by dipole analysis and regional
sources using methods published in the literature. Results: For none of the mixtures a significant effect of tryptophan depletion was found. There was a trend towards reduced intensity
dependency after tryptophan depletion, especially in the right hemisphere. This reduction correlated with the amount of reduced
tryptophan in plasma. Conclusions: The results indicate, in contrast to earlier indirect studies, that the intensity dependence of AEPs is not a specific marker
of central serotonergic activity.
Received: 8 March 1999 / Final version: 25 May 1999 相似文献