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81.
The protein patterns of tissue homogenates from human deciduaand placenta of first trimester pregnancies were investigated.Particular attention was paid to the low molecular weight componentsof these tissues, since substantial evidence has accumulatedthat some of these smaller proteins show a characteristic cyclicand pregnancy expression. Two specific bands were purified fromhomogenates of first trimester decidua and placenta using gelfiltration and anion exchange chromatography. These bands wereseparated by gel electrophoresis and blotting onto polyvinylidendifluoridemembrane. Partial amino acid sequencing of both proteins revealedsequences identical to human cyclophilin A. One protein wassequenced V-N-P-T-V-F-F-D-I-A-V-D-G-E-P-L-G-R-(X)-S-F-E-L-F-A-D-K-V-Pand identified as the 17 kDa isoform of cyclophilin A. The otherprotein was sequenced V-N-P-T-V-F-F-D-I-A and identified asthe 18 kDa isoform of cyclophilin A. cyclophilin A/decidua/placenta/progesterone/progesterone receptor  相似文献   
82.
The DR7-associated Dw specificities, Dw11, Dw17 and DB1 were investigated with regard to DRB- and DQB-gene polymorphism, as revealed by RFLP analysis using the restriction enzyme TaqI. In the 22 DR7 homozygous cell lines investigated, each of these Dw specificities was found to correlate to one specific RFLP defined DR-DQ haplotype. In addition, a clear linkage disequilibrium to a specific HLA-B locus allele for each Dw specificity was noted, indicating that the Dw subtypes of DR7 often are associated with a conserved HLA-B-DR-DQ haplotype. Only one genetically homozygous cell line, PLH, deviated from these correlations. This cell line, notably derived from an individual with a deletion of the 21-hydroxylase B-gene (21-OHB), caries the HLA haplotype Bw47, DR7, DQw2, DB1, but displayed a DRB RFLP otherwise found in association with Dw17.  相似文献   
83.
Pulsed presentations of auditory stimulation have been shown to be particularly effective in eliciting cardiac deceleration (orienting) during earliest infancy. In the present study the processing of pulsed as compared to continuous stimulation was studied developmentally for two infant age groups (13–18 and 26–35 weeks) and one adult group. Ten habituation trials of either a pulsed or a continuous 10-sec tone were followed by 2 dishabituation trials, in which the temporal pattern (continuous vs pulsed) was shifted. The dishabituation data showed that the two kinds of stimulation were discriminated, but the only finding of differential processing relating to the relevance of pulsed stimulation for younger infants was a tendency for infant subjects, unlike adults, to show prolonged orienting to initial presentations of the pulsed tone. For rate of habituation there were no differential effects. Only in the adult group was the response during dishabituation influenced by the direction of change of temporal pattern. Orienting to stimulus offset was observed on initial presentations of the continuous stimulus for the older infant group.  相似文献   
84.
Postural effects on muscle nerve sympathetic activity in man   总被引:6,自引:4,他引:6       下载免费PDF全文
1. Pulse-synchronous bursts of multi-unit sympathetic activity (MSA) were recorded in peroneal muscle nerve fascicles in eight healthy subjects when lying, sitting and standing. The sympathetic activity was quantitated by counting the number of bursts in the mean voltage neurogram/min. Postural changes were analysed by considering the total activity to be a product of the number of bursts in relation to the number of heart beats (burst incidence) and the heart rate.2. In lying there were large interindividual differences in total activity, but for all subjects the activity increased when going from lying to sitting and from sitting to standing. With a few exceptions the increase between the lying and sitting postures was associated with an increase in both burst incidence and heart rate whereas between the sitting and standing postures there was an increase in heart rate but on the average no change in burst incidence.3. When going from lying to sitting or from sitting to standing the magnitude of the change in burst incidence was inversely related to the initial burst incidence so that subjects with low initial values usually showed greater increases in burst incidence than subjects with high initial values. Some subjects with high initial values decreased their burst incidence.4. With changes in postures there was an inverse linear relationship between the fraction of the change in MSA associated with a change in burst incidence and the fraction associated with a change in heart rate. An increase in total activity could be obtained by changing only burst incidence, by increasing heart rate without changing burst incidence, or by appropriate changes in both parameters. The slope of the regression line was -0.53 indicating that for adequate postural compensation fewer additional bursts were required when the compensatory response involved an increase in heart rate rather than an increase in only burst incidence.5. It is suggested that an impairment of the ability to regulate heart rate will make subjects with high burst incidence in the lying position orthostatically more vulnerable than those with low burst incidence.6. Shortly after standing up one subject developed bradycardia and subsequently fainted. The nerve recording was maintained until the subject collapsed. During the initial bradycardia no sympathetic bursts occurred suggesting that the syncope was associated with an interruption of normal baroreflex feedback between blood pressure and sympathetic outflow.  相似文献   
85.
The isthmo-optic nuclei (ION) and ectopic neurons, which constitute the centrifugal visual system (CVS), are thought to be cholinoceptive and nitrergic. However, it is not clear which neurons express these markers, namely the ones that project to the retina rather than in neurons that only participate in a local circuit. Therefore, to characterize the neurochemical patterns of the centrifugal visual system in the post-hatched chick, retinopetal cells of the isthmo-optic nuclei and the ectopic region were identified via immunolabeling for cholera toxin, a neuronal tracer, which has been injected in the ocular globe. Then, double labeled with acetylcholinesterase histochemistry to reveal cholinergic synapses, or NADPH-diaphorase histochemistry as a nitrergic marker. Briefly, acetylcholinesterase activity was present mainly in cholera toxin labeled cell bodies of the isthmo-optic nucleus and the ectopic region indicating that retinal projecting neurons of centrifugal visual system comprise a cholinoceptive pathway. On the other hand, NADPH-diaphorase histochemistry was present in the neuropile and sparse cell bodies inside of the isthmo-optic nucleus and in ectopic neurons which were not cholera toxin positive suggesting their role in an intrinsic circuit of the centrifugal visual system. These data support the idea that these two neurochemical systems are present in distinct neuronal populations in the centrifugal visual system.  相似文献   
86.
Summary The purpose of the study was to analyse the effect of arm-shoulder fatigue on manual performance. Ten experienced carpenters performed three standardized tasks (nailing, sawing and screwing). Electromyographic activity was recorded from six arm-shoulder muscles and the performances were video-filmed. After 45 min of standardized arm-cranking (arm-shoulder-fatiguing exercise of approximately 70%–80% maximal oxygen consumption), the tasks were repeated. The number of work movements and the time taken for each task were recorded and the quality of the work performed was compared. After the fatiguing exercise, only nailing was perceived as being harder and more mistakes were made during nailing and sawing. Movement performance was not influenced during nailing but was slightly slower during sawing and faster during screwing. However, there were increased mean EMG amplitudes in the upper trapezius and biceps muscles during nailing, in the upper trapezius, anterior deltoid and infraspinatus muscles during sawing and in the anterior deltoid muscle during screwing. Of the muscles studied the upper trapezius and anterior deltoid muscles increased their activity most after the arm-shoulder-fatiguing exercise.  相似文献   
87.
Quality of Life Research - The objective of this study was to determine the influence of postanesthesia care unit (PACU) delirium on self-reported cognitive function and perceived health...  相似文献   
88.
89.
Pertussis is a globally distributed infectious disease that is a significant cause of morbidity and mortality, especially in infants who are too young to be immunized. This disease is common in childhood, and when it occurs during the first few months of life, it leads to hospitalization and, sometimes, death. Brazil has adopted the strategy of maternal immunization against pertussis in late 2014. This study aims to analyze public data on the disease to determine whether there was an impact on the disease burden following the introduction of the vaccine Tdap in pregnant women and its magnitude. We performed a time-series analysis of the incidence of pertussis between October 2010 and January 2019. We stratified the population of interest into three groups: infants aged less than two months old, infants aged two to six months, and infants aged six months to one year, according to Brazil's vaccination schedule. We found a protective effect of maternal vaccination in all age groups, more prominent on the first group. Before the intervention, infants under two months had a higher risk of getting pertussis in comparison with infants two to six months old (HR 1.15, CI 95%: 1.11–1.19). After the intervention, age under two months is a protective factor compared with two to six months (HR 0.90, CI 95%: 0.82–0.98). The pertussis incidence reduced in all age groups and all Brazil's Regions.  相似文献   
90.
Objective:Knowledge of the relationship between psychosocial strain in the work environment and smoking during pregnancy is scarce. This study aimed to examine the association between psychosocial job strain and change in smoking behavior during pregnancy.Methods:The cohort included 65 645 pregnancies from the Danish National Birth Cohort (1996–2002), where pregnant women were interviewed on job factors and lifestyle during the first and third trimesters. Smoking was categorized into non-, non-daily, and daily smoking at each interview. Psychosocial job strain was categorized into four groups based on the concept of Karasek’s demand–control model: low strain (reference), passive, active and high strain. Associations between psychosocial strain and change in smoking status between the first and second interviews were analyzed by multinomial logistic regression, separately for each smoking category at first interview.Results:Non-smoking women exposed to high strain work were more likely to become daily smokers [adjusted odds ratio (ORadj) 1.41, (95% confidence interval (CI) 1.08–1.83)] compared to non-smoking women exposed to low strain work. Non-smoking women exposed to passive work were more likely to become both non-daily and daily smokers [ORadj 1.59 (95% CI 1.21–2.08) and ORadj 1.32 (95% CI 1.03–1.70), respectively]. Daily smoking women exposed to high strain work were less likely to decrease their smoking [ORadj 0.57 (95% CI 0.32–0.99)] compared to daily smoking women exposed to low strain work.Conclusions:Psychosocial strain influenced the women’s smoking behavior during pregnancy, especially in job types with low control.  相似文献   
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