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961.
Patricia K P Burnell Lars Asking Lars Borgstr?m Steve C Nichols Bo Olsson David Prime Ian Shrubb 《Journal of aerosol medicine》2007,20(3):269-281
Magnetic resonance imaging (MRI) of the oropharyngeal region from 20 adult volunteers using four model inhalation devices (varying mouthpiece diameters, airflow resistances) and tidal breathing was carried out. Statistical analysis (convex hull method) selected 12 scans from 80 data sets representing the extremes of all dimensions in the population. Twelve physical mouth-throat models were made by stereolithography using the exact scan data. The aim was to produce models with varying dimensions to span the adult population, and to investigate if oropharyngeal dimensions affected throat retention for different delivery systems. In an in vitro analysis, the models were used to determine the retention effect of the oropharyngeal airspaces when drug aerosols were administered from four inhalation delivery systems: a pressurised metered dose inhaler (pMDI), two different dry powder inhalers (DPIs A and B), and a nebulizer. The aims of this work were to determine the key parameters governing mouth-throat retention and whether retention was dependent on the delivery system used. Characterizing the throat models by measuring 51 different dimensional variables enabled determination of the most influential variables for dose retention for each inhalation delivery system. Throat model retention was found to be dependent on the delivery system (pMDI approximately DPI(A) > DPI(B) > Neb.). The most influential variable was the total throat model volume. Throat models representing high, median, and low oropharyngeal filtration in healthy adults have been identified. 相似文献
962.
963.
E. P. Kemertelidze K. G. Shalashvili B. M. Korsantiya N. O. Nizharadze N. Sh. Chipashvili 《Pharmaceutical Chemistry Journal》2007,41(1):10-13
The sum of phenolic compounds was obtained from the leaves of Caucasian endemic plant Rhododendron ungernii (Trautv.) in the amount of 7%. The extract contains flavonoids, catechins, and anthocyanidins, in particular, quercetin,
isoquercetin, quercitrin, hyperin, rutin, (+)-catechin, (−)-epicatechin, (+)-gallocatechin, and leucoanthocyanidins. The sum
of phenolic compounds from Rhododendron ungernii completely inhibits Herpes simplex virus reproduction in a bioassay. A new medicinal preparation (Rhodopes) in the form of
a 5% ointment was created on the basis of this extract and tested under clinical conditions at a dental clinic and three other
specialized medical departments. The results showed a high therapeutic efficacy: Rhodopes favorably influenced the state of
patients and caused neither mucosa irritation nor allergic and other adverse reactions. Rhodopes has received State Registration
and is recommended for the treatment of all forms of herpetic disorders.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 41, No. 1, pp. 10–13, January, 2007. 相似文献
964.
965.
966.
Background Pityrosporum ovale is a common saprophyte on the skin capable of inducing IgE antibody production in atopic dermatitis (AD) patients. Allergens ofP. ovale have been examined in several studies, but consensus on them is lacking. Objective This study was carried out to obtain more information about the IgE antibody response against P. ovale. including niunnun. Methods Sera from 64 AD patients and 10 healthy controls were analysed with immuno-blotting and the nitrocellulose radio allergosorbent test (RAST) method specifically developed to detect antimannan P. ovale IgE antibodies. Results In immunoblotting a total of 39 different IgE stained protein bands were seen. A high molecular weight staining was also seen especially in patients who displayed elevated mannan P. ovale RAST values. The most commonly stained protein bands in immunoblotting were 9 and 96 kD bands with antibodies in 73 and 65% of AD patients who had been positive in commercial P. orbiculare RAST with total serum IgE less than 4000 kU/I. Mannan RAST appeared positive in 77% of them. Positive immunoblotting to either of these bands was seen in 90% and, if added with staining with ihe 20 kD band, in 100% of these AD patients. A comhination of 9 kD IgE staining and mannan P. ovale RAST was positive in 92% of the patients and % kD and mannan P. ovale RAST in 85% of the patients. Conclusion It is evident that P. ovale has several allergens, the 9. 96 and 20 kD regions being the most important. According to our results mannan is also an important allegen of P. ovale 相似文献
967.
Background: Retinal pigment epithelium (RPE)lesions are predictive congenital phenotypic markersfor familial adenomatous polyposis (FAP). Thisprospective screening study aims at assessing theincidence and significance of these lesions in FAPpatients and their family members.Methods: Sixty-two members from three familiesincluding five patients with the diagnosis of FAP havebeen ophthalmologically surveyed. All RPE lesions weredocumented with fundus photography and fluoresceinangiography was performed in 13 subjects.Sigmoidoscopy and/or radiological examination wereperformed annually in 9 family members with typicalRPE lesions during 4 years to allow early diagnosis ofFAP.Results: Typical RPE lesions were present infive FAP patients and 15 family members.Telangiectatic dilatations in the retinal peripherywith small dot-like hemorrhages were detected in 6subjects from 3 families These lesions wereparticularly evident on fluorescein angiography.Annual colon analysis showed polyps in 3 out of 9subjects who were positive for RPE lesions.Conclusion: RPE lesions are valuable as aclinical marker in predicting FAP. The co-existingperipheral vascular alterations which have not beenreported before, are probably related to FAP. 相似文献
968.
Dr. E. Mietzsch M. Koch M. Schaldach J. Werner B. Bellenberg K. U. Wentz 《Medical & biological engineering & computing》1998,36(6):673-678
The application of spin-echo magnetic resonance imaging sequences on non-invasive temperature imaging for temperature mapping
of human limbs is investigated. In an in vitro expriment performed on a meat sample, the equilibrium magnetisation P and the
spin-lattice relaxation time T1 are calculated from the values for the repetition time TR and the signal intensities obtained by a spin-echo sequence at
different tissue temperatures tures as measured by a fibre-optic probe. T1 is linearly correlated to the tissue temperature, and P is linearly correlated to the reciprocal value of the absolute temperature.
Both effects, taken together, lead to a non-linear dependency of the signal intensity on temperature. Therefore a TR leading
to maximum temperature dependency of the signal intensity is calculated and used in the futher experiments. In the in vivo
experiments, the lower legs of two volunteers are cooled from outside. Images are acquired with a spin-echo sequence (1.5T,
TR=1200 ms, TE=10 ms). A rise in signal intensity in the muscle with falling skin temperature is observed, particularly in
more peripheral muscle layers. This study shows that spin-echo sequences can be used to monitor temperature changes and temperature
differences in living muscle tissue. 相似文献
969.
Back pain in in-vitro fertilized and spontaneous pregnancies 总被引:1,自引:0,他引:1
Kristiansson P; Nilsson-Wikmar L; von Schoultz B; Svardsudd K; Wramsby H 《Human reproduction (Oxford, England)》1998,13(11):3233-3238
The influence of ovarian stimulation in in-vitro fertilization (IVF) on the
prevalence of back pain with onset during pregnancy was studied in 31 women
who became pregnant after IVF treatment and compared with that of 200
spontaneously pregnant women. A two times higher prevalence rate of sacral
pain in late pregnancy was reported among IVF pregnant women (P <
0.0001), as well as a significantly higher prevalence rate of positive
results of pelvic pain provocation tests performed in late pregnancy
(0.0001 < or = P < or = 0.015), as compared with that of the
spontaneously pregnant women. Among the IVF pregnant women, there was a
significant positive correlation between relaxin concentrations in early
pregnancy and the outcome of pelvic pain provocation tests (0.44 < or =
r < or = 0.51, P < 0.05). In addition, the serum relaxin
concentration was the factor that best explained differences in sacral pain
prevalence. When the influence of serum relaxin concentration on back pain
prevalence was taken into account, women carrying multiple pregnancies had
no more pain than women carrying singletons, and IVF pregnant women had no
more pain than spontaneously pregnant women. These results support the
hypothesis that relaxin is involved in the generation of pelvic pain in
pregnant women.
相似文献
970.