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61.
Laserspectroscopy with near-infrared light is newly available for clinical application. The equipment consists of a near-infrared data collection unit (NIRDCU) and a personal computer. Emission of laser light at wavelengths of 775, 805, 845 and 904 nm is provided by the four laser diodes of the NIRDCU. By analyzing changes of optical density during laser radiation, information is obtained regarding the intracellular redox state and relative changes of blood volume. During measurement with the system on the fetal scalp during delivery we were able to get a first impression of the method's potential. While the application of the laser sensors is still cumbersome, signals providing information of the relative changes of hemoglobin concentration, relative changes of blood volume and cytochrome aa3 seems achievable. Laserspectrophotometric monitors may become safe, low cost and portable instruments for the non-invasive assessment of the biochemical and biophysical status in the fetus.  相似文献   
62.
The formation of toxic substances in the skin, due to the influence of thermal energy, is supposed to be one possible mechanism responsible for the high mortality rate after severe burns covering large areas of the body surface. The effects of low-molecular-weight volatile substances (dry distillates) generated after burning mouse skin were investigated. They led to reductions of the respiratory activity of rat liver mitochondria. Among other substances carbon disulphide, methylethylketone and pyrrole were isolated and characterized using gas chromatography. All of them had strong uncoupling effects on mitochondrial respiration. In a second study respiratory measurements were made on mitochondria from rats with 20-30 per cent TBSA full skin thickness burns. A decreased respiratory control ratio and thus uncoupling of mitochondrial respiration was found on days 1, 2 and 5 postburn. The basal mitochondrial respiration was significantly decreased on day 5, which could be important for the mortality mentioned above. Finally after cross-transplantations rats having burned skin grafted showed a reduction of the RCR when compared with rats with the unburned graft. Thus it can be concluded that toxic substances must have been present in burned skin.  相似文献   
63.
64.
Dorsal root ganglion cells with axons innervating the cat's knee joint via the medial articular nerve were retrogradely labelled with Fast blue. Neurokinin A-like immunoreactivity was found in 4.5 +/- 1.1% (mean +/- S.D. of 5 nerves and 695 cells) of the articular afferents. Colchicine treatment of the ganglia increased the percentage of immunopositive cells to 8.5 +/- 0.7% (mean +/- S.D. of 6 nerves and 554 cells) after 3-22 h. The diameter distribution of the immunopositive somata ranged from 20 to 50 microns with a maximum at 26-30 microns. Comparing the proportions of neurokinin A-immunopositive cells with those of substance P, it can be calculated on the basis of mRNA encoding that neurokinin A is synthetized in about half of the substance P-containing primary articular afferents.  相似文献   
65.
Five male and female rats per dose-group received 2,3,7,8-tetrabromodibenzo-p-dioxin (2,3,7,8-TBDD) once on the first day of the study. Doses of 10, 33, 100, or 300 micrograms 2,3,7,8-TBDD/kg body wt. and the vehicle control were administered by gavage. About 20% of 2,3,7,8-TBDD was excreted via feces. Severe body weight retardation was observed in the 100 and 300 micrograms/kg dose-groups. Most animals in the 300 micrograms/kg dose-group and the females receiving 100 micrograms/kg showed emaciation, rough coat and a poor health (wasting syndrome). Of the animals dosed with 300 micrograms/kg, 3 males and all females died. After 100 micrograms 2,3,7,8-TBDD/kg 3 females died. Measured 4 weeks after dosing, triiodothyronine (T3) was increased and thyroxin (T4) was reduced dose dependently in serum. A dose-dependent decrease in thymus weights was observed at necropsy and histological examinations showed that thymus and spleen were depleted of mature lymphocytes. An increase in liver-to-body weight ratio was observed in all dose-groups. The histological examination revealed hypertrophy of centrilobular hepatocytes in the liver of animals treated with 100 micrograms/kg, which was less severe at the 33 micrograms/kg dose. Hypertrophic hepatocytes were also detected in some animals at the lowest dose. Induction of enzyme activities of the mixed function oxidases ethoxycoumarin O-deethylase (ECOD), ethoxyresorufin O-deethylase (EROD) and aryl hydrocarbon hydroxylase (AHH) in liver tissue differed for each of the three enzymes. Two days after administration, enzyme activities were increased but did not differ substantially between dose-groups. Twenty-eight days after dosing the increase in activity after 10 micrograms/kg was largest and the EROD of the 100 micrograms/kg dose-group in females was close to that of the control. This inverse dose-response relationship may be due to impaired liver cell function at higher doses.  相似文献   
66.
Zusammenfassung Grundlagen: Der Zweck war es, die Anzahl der im Mammogramm entdeckten duktalen Carcinoma in situ (DCIS) und multizentrische Karzinome aufzudecken. Die verschiedenen Methoden der Biopsie werden diskutiert. Methodik: Rastermammographie (Fokus 0,3 mm) und hochaufl?sende Sonographie (7,5 bis 10 MHz) wurden bei Brustkrebspatientinnen eingesetzt. Ergebnisse: Der Zeitraum der aufgelisteten Patientinnen erstreckt sich über 20 Jahre. Die Zahl der DCIS hat in den letzten Jahren zugenommen und betr?gt nun 18%. Die Mammographie ist hoch sensitiv für Entdeckung von Mikrokalzifikationen. Die Spezifit?t ist gering. Schlu?folgerungen: Die Anzahl der entdeckten DCIS ist in den letzten Jahren besonders angestiegen und wird auch noch weiter bei Verbesserung der mammographischen Techniken ansteigen. Diese Studie wurde vom Ludwig-Boltzmann-Institut für radiologisch-physikalische Tumordiagnostik unterstützt.  相似文献   
67.
Based on the hypothesis that condensation products of neurotransmitters with aldehydes are involved in the pathogenesis of alcoholism, aromatic beta-carbolines (norharman and harman) were measured in the blood plasma of alcoholics and nonalcoholics. The identity of the extracted compounds was confirmed by various elution conditions of the high performance liquid chromatography (HPLC), newly developed radioreceptor assays, and the mass spectrum of norharman. The levels of norharman and harman in nonalcoholics were unchanged after a load with ethanol (1 g/kg body weight). The norharman levels of the alcoholics were significantly higher than that of the nonalcoholic controls (99.5 +/- 26.6 pg/ml vs. 26.9 +/- 10.7 pg/ml; p less than 0.001) and did not change significantly during a 3-week detoxication period. In the subgroup of alcoholics with delirium or hallucinosis, a slight increase of norharman during detoxication could be detected while in alcoholics with vegetative withdrawal symptoms norharman levels dropped slightly over time (p = 0.07). No difference was found with respect to harman between nonalcoholics and alcoholics. These results suggest disturbed regulatory processes in the formation and/or metabolism of norharman in alcoholics. Further investigations are needed to reveal a possible marker function of norharman in alcoholic patients.  相似文献   
68.
This study was designed to assess the reliability and validity of a Quality of Life (QOL) instrument on a sample of 179 allogeneic Bone Marrow Transplant (BMT) survivors. The QOL-BMT tool was developed specifically for this population and was based on the investigators' prior research and a conceptual model of Quality of Life. Patients who were at least 100 days post BMT completed the 30 item visual analogue questionnaire. The instrument measured physical symptoms (e.g., weight loss, frequent colds, skin changes, cataracts, sexual problems), psychological to illness, social concerns (e.g., relationship adjustment, return to work), and spiritual well-being (e.g., sense of control, future goals). Psychometric analysis of the instrument included measures of reliability and validity. The study findings demonstrate the unique aspects of QOL dimensions in BMT survivors and the value of QOL assessment in clinical practice and research.This study was supported by the City of Hope National Medical Center, NCI Cancer Center Core Grant, R30 CA 33572 and the City of Hope BRSG Grant Support.  相似文献   
69.
Using an experimental model of continuous endotoxin infusion, the effects of castration, testosterone and estrogen substitution on disseminated intravascular coagulation in male rats were investigated. Male rats which are not pretreated react in the same way to an endotoxin infusion as female animals, with an increase in free plasma hemoglobin, decrease of fibrinogen level, decrease of hematocrit and platelets and glomerular fibrin depositions. Different experimental groups of testectomized rats were pretreated with (i) 0.3 micrograms (pregnancy-conserving dose) or (ii) 30 micrograms ethinylestradiol (ovulation-suppression dose) or (iii) 250 mg testosterone. They were then compared to groups of animals treated with sesame oil as well as untreated group of rats. The pretreatment with testosterone and estrogens in the small-dose group had only an insignificant effect on the shock sequence. Only those animals which were treated with a high dose of estrogens showed a dramatic enhancement of their endotoxin sensitivity. It was also shown that in male animals an increased estrogen level might mediate a state of 'preparation', but testosterone does not 'prepare' castrated rats for the generalized Schwartzman reaction. The possible significance of enhancement of endotoxin toxicity by estrogens in explaining some pathophysiological characteristics of disseminated intravascular coagulation in pregnancy is discussed.  相似文献   
70.
In the sick sinus syndrome, in sinu-atrial conduction defects or in atrial flutter or fibrillation a stress-adapted, frequency-adapted stimulation cannot be obtained by the processing of the atrial potential. Here one depends on partly extracardiac parameters which contain informations about the metabolic and stress situation, respectively. A survey of the parameters for a frequency-adapted stimulation discussed at present is given and a critical valuation of them is carried out. It is shown that all parameters up to now experimentally and clinically, respectively, tested are more or less problematic and that the way out of the difficulty most consist in deriving the controlled variable for a stress adapted stimulation rate from several parameters.  相似文献   
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