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991.
992.
This study examined whether psychosocial assistance in childhood predicted coping strategies, family atmosphere, learning experiences and mental health in adulthood. Participants were 153 Chileans (14–30 years old) who, as children, had lost a family member through political imprisonment, execution, disappearance, or expulsion from the country. SEM‐modeling revealed that early timing and substantial duration of psychosocial assistance in childhood predicted good mental health and positive learning experiences in adulthood via effective coping strategies. In addition, a family atmosphere characterized by high cohesion and a low level of conflict associated with good mental health and positive learning experiences. Both the nature of childhood trauma and the timing and duration of assistance turned out to be crucial for later resourcefulness and well‐being. Children who had lost a parent as executed or disappeared were the most task‐oriented and conscientious students and enjoyed a harmonious family life. Early initiation and substantial duration of assistance predicted lower levels of poor mental health symptoms (posttraumatic, depressive, anxiety, somatic, and aggressive) in adulthood. © 2001 John Wiley & Sons, Inc.  相似文献   
993.
Aging is commonly associated with decreased sleep quality and increased periodic breathing (PB) that can influence heart rate variability (HRV). Cardiac autonomic control, as inferred from HRV analysis, was determined, taking into account the sleep quality and breathing patterns. Two groups of 12 young (21.1 +/- 0.8 years) and 12 older (64.9 +/- 1.9 years) volunteers underwent electroencephalographic, cardiac, and respiratory recordings during one experimental night. Time and frequency domain indices of HRV were calculated in 5-min segments, together with electroencephalographic and respiratory power spectra. In the elderly, large R-R oscillations in the very-low frequency (VLF) range emerged, that reflected the frequency of PB observed in 18% of the sleep time. PB occurred more frequently during rapid eye movement sleep (REM) sleep and caused a significant (P < 0.02) increase in the standard deviation of normal R-R intervals (SDNN) and absolute low-frequency (LF) power. With normal respiratory patterns, SDNN, absolute VLF, LF, and high frequency (HF) power fell during each sleep stage (P < 0.01) compared with young subjects, with no significant sleep-stage dependent variations. An overall decrease (P < 0.01) in normalized HF/(LF + HF) was observed in the elderly, suggesting a predominant loss of parasympathetic activity which may be related to decreased slow-wave sleep duration. These results indicate that two distinct breathing features, implying different levels of autonomic drive to the heart, influence HRV in the elderly during sleep. The breathing pattern must be considered to correctly interpret HRV in the elderly.  相似文献   
994.
We compared a rapid slide latex agglutination test (LAT; Oxoid, Basingstoke, United Kingdom) that detects penicillin binding protein 2a (PBP2a) with MicroScan conventional panels (Dade Behring, West Sacramento, CA) for detection of oxacillin resistance in Staphylococcus aureus. The PBP2a LAT demonstrated 99% agreement with MicroScan oxacillin MIC results for 388 isolates of S. aureus. All 249 oxacillin-resistant isolates gave strong positive reactions in the LAT (100% sensitivity). Three of the 139 oxacillin-susceptible isolates were also strongly positive and one was weakly positive in the LAT (97.1% specificity). The three oxacillin-susceptible isolates with strongly positive reactions were further characterized. The mecA gene was detected in all three by PCR; one isolate was determined to be resistant to oxacillin by reference broth microdilution testing (MIC, 8 microg/ml), one isolate was inducibly resistant to oxacillin (MIC of 16 microg/ml after overnight induction), and one isolate remained susceptible regardless of the method used for testing. Sequence analysis of a 2.1-kb gene fragment of the mecA gene from the susceptible isolate revealed a one-base substitution at nucleotide position 1449 which results in a Met-to-Ile change for amino acid residue 483. This amino acid substitution has not been previously reported and may be associated with a change in the function of PBP2a resulting in oxacillin susceptibility. An additional 487 isolates were tested in parallel with the both the LAT and MicroScan panels using criteria in which only strong (3 to 4+) or repeatedly weak (1 to 2+) LAT reactions were considered positive, and the results showed 99.4% agreement. The PBP2a LAT provided rapid and reliable detection of oxacillin resistance and proved a useful adjunct to the phenotypic method. Both methods provided reliable detection of oxacillin-resistant S. aureus and facilitated the discovery of a novel, functionally impaired form of PBP2a.  相似文献   
995.

Background  

The Pro12Ala Single Nucleotide Polymorphism (SNP) of the Peroxisome Proliferator-Activated Receptor gamma 2 (PPAR-gamma 2) has been associated with insulin resistance and type 2 diabetes (T2D) and also inconsistently with obesity. The aim of this study was to evaluate the impact of this SNP with regards to T2D and childhood and adult obesity in the French Caucasian population.  相似文献   
996.
Kallmann syndrome (KAL) combines hypogonadotropic hypogonadism and anosmia. Hypogonadism is due to Gonadotropin Releasing Hormone (GnRH) deficiency and anosmia is related to hypoplasia of the olfactory bulbs. Occasional symptoms include renal agenesis, bimanual synkinesia, cleft lip palate, dental agenesis. KAL is genetically heterogeneous and two genes have so far been identified, namely KAL1 (Xp22.3) and FGFR1/KAL2 (8p12), which underlie the X chromosome‐linked form and an autosomal dominant form of the disease, respectively. We studied a cohort of 98 unrelated Caucasian KAL patients. We identified KAL1 mutations in 14 patients, of which 7 (c.3G>A (p.M1?), g.IVS1+1G>T, c.570_571insA (p.R191fsX14), c.784G>C (p.R262P), c.958G>T (p.E320X), c.1651_1654delinsAGCT (p.P551_E552delinsSX), c.1711T>A (p.W571R)) have not been previously reported. In addition, we found FGFR1 mutations in 7 patients, namely c.303G>A (p.V102I), C.385A>C (p.D129A), c.810G>A (p.V273M), c.1093_1094delAG (p.R365fsX41), c.1561G>A (p.A520T), c.1836_1837insT (p.Y613fsX42), c.2190C>G (p.Y730X), all of which were novel mutations. In this study, unilateral renal agenesis and bimanual synkinesia were exclusively found associated with KAL1mutations, cleft palate and dental agenesia with FGFR1mutations. © 2004 Wiley‐Liss, Inc.  相似文献   
997.
Summary: Light‐induced reversible changes in elasticity of semi‐interpenetrating network (semi‐IPN) films bearing azobenzene moieties were achieved under both ultraviolet (UV) and visible light irradiation. The semi‐IPN film was prepared by a cationic copolymerization of azobenzene‐containing vinyl ethers in a linear polycarbonate (PC) film as a matrix. When the irradiation was switched on and off, the semi‐IPN film showed rapid reversible deformation with the same behavior occurring over a range of wavelengths, including both the UV and visible regions. The observed reversible deformation of the film was attributed to the decrease in the film's elasticity, which was assumed to be caused by the frequent transcis cycling isomerization of azobenzene moieties taking place during the UV and visible light irradiation. This cycling makes it difficult for the azobenzene groups to aggregate, thus hindering their ability to function as pseudo‐crosslinking points.

  相似文献   

998.
999.
We describe for the first time extended haplotypes in a Croatian population. The present study gives the HLA‐A, ‐B, ‐DRB1, ‐DQA1 and ‐DQB1 allele and haplotype frequencies in 105 families with at least two offspring. All individuals were studied by conventional serology for HLA class I antigens (A and B), while class II alleles (DRB1, DQA1, DQB1) were typed using the PCR–SSOP method. HLA genotyping was performed by segregation in all 105 families. For extended haplotype analysis, 420 independent parental haplotypes were included. Fourteen HLA‐A, 18 HLA‐B, 28 DRB1, 9 DQA1 and 11 DQB1 alleles were found in the studied population. Most of the DRB1 alleles in our population had an exclusive association with one specific DQA1‐DQB1 combination. This strong linkage disequilibrium within the HLA class II region is often extended to the HLA‐B locus. A total of 10 HLA‐A, ‐B, ‐DRB1, ‐DQA1, ‐DQB1 haplotypes were observed with a frequency ≤ 1.0%. The three most frequent haplotypes were HLA‐A1, B8, DRB1*0301, DQA1*0501, DQB1*0201; HLA‐A3, B7, DRB1*1501, DQA1*0102, DQB1*0602 and HLA‐A24, B44, DRB1*0701, DQA1*0201, DQB1*02. These results should provide a useful reference for further anthropological studies, transplantation studies, and studies of associations between HLA and diseases.  相似文献   
1000.
STUDY OBJECTIVES: To develop a single-administration instrument yielding equivalent measures of sleep to those obtained from a formal (2-week) sleep diary. DESIGN & SETTING: A single-administration Sleep riming Questionnaire (STQ) is described (and reproduced in the Appendix). Test-retest reliability was examined in 40 subjects who were given the STQ on two occasions separated by less than 1 year. Convergent validity was measured both by comparing STO-derived measures with objective measures derived from wrist actigraphy (n=23) and by comparing STQ-derived measures with other subjective measures derived from a detailed 2-week sleep diary in two nonoverlapping samples (n=101, 93). Correlations of STQ measures with age and momingness-eveningness (chronotype) were also examined. SUBJECTS: The analyses used sample sizes of 40, 23, 101, and 93 (both genders, overall age range 20y-89y). Most subjects were healthy volunteers; some Study 4 subjects were patients (enrolled in research protocols). RESULTS: Test-retest reliability for the STQ was demonstrated for estimates of bedtime (r = 0.705, p < 0.001) and waketime (r = 0.826, p < 0.001). Convergent validity using wrist actigraphy was demonstrated by correlations of 0.592 (p < 0.005) for bedtime, and of 0.769 (p < 0.001) for waketime. Diary studies indicated STQ bedtime and waketime data to be highly correlated (at about 0.8) with those obtained from a formal 2-week sleep diary. The STQ also provided data on estimated sleep latency and wake after sleep onset (WASO), which correlated reliably (at about 0.7) with average nightly ratings of these variables from a 2-week sleep diary. Mean estimated values of sleep latency and WASO from the two instruments were within 1 minute of each other. ST-derived bedtimes and waketimes correlated with both age and chronotype in the expected direction (older subjects earlier, morning types earlier). CONCLUSION: The STQ may be a reliable valid measure of sleep timing that could provide a time-efficient alternative to traditional sleep diaries.  相似文献   
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