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71.
Aim: To evaluate children born post-term (gestational age ≥42 weeks) with respect to developmental data obtained at the ages of 4 and 5.5 y. Methods: The study population included all children (n=354) born in 1991 at Huddinge University Hospital with a gestational age of ≥42 wk. The births were identified and perinatal data were collected through the Swedish National Birth Registry. Developmental assessments from the child health centres were analysed. Children born at term, but before a gestational age of 42 wk, served as controls. Logistic regression analysis was used to analyse the data. Results: Children born post-term had more developmental deviations than the controls (estimated odds ratio 2.20; 95% CI: 1.29-3.85). Boys had more deviations than girls (estimated odds ratio 1.92; 95% CI: 1.11-3.45).

Conclusion: Our results indicate that there might be an association between post-term birth and developmental deviations.  相似文献   
72.
Several lines of evidence suggest that D-serine, an endogenous agonist of the glycine site on the NMDA receptors, might play a role in the pathophysiology of schizophrenia. The purpose of this study was to determine whether levels of D- and L-serine or D-serine ratio (D-serine/total serine) in cerebrospinal fluid (CSF) were altered in first episode and drug-naive schizophrenic patients. The CSF levels of D- and L-serine in 25 male first episode and drug-naive schizophrenic patients and 17 age-matched male healthy subjects were measured using a column-switching high performance liquid chromatography system. The percentage of D-serine in the total serine of patients was significantly (z = -2.01, p = 0.044) lower than that of controls. This study suggests that synthetic or metabolic pathways of D-serine may be abnormal in the brain of drug-naive schizophrenic patients, supporting the NMDA receptor dysfunction hypothesis of schizophrenia.  相似文献   
73.
Sex steroid-related genes and male-to-female transsexualism   总被引:4,自引:0,他引:4  
Transsexualism is characterised by lifelong discomfort with the assigned sex and a strong identification with the opposite sex. The cause of transsexualism is unknown, but it has been suggested that an aberration in the early sexual differentiation of various brain structures may be involved. Animal experiments have revealed that the sexual differentiation of the brain is mainly due to an influence of testosterone, acting both via androgen receptors (ARs) and--after aromatase-catalyzed conversion to estradiol--via estrogen receptors (ERs). The present study examined the possible importance of three polymorphisms and their pairwise interactions for the development of male-to-female transsexualism: a CAG repeat sequence in the first exon of the AR gene, a tetra nucleotide repeat polymorphism in intron 4 of the aromatase gene, and a CA repeat polymorphism in intron 5 of the ERbeta gene. Subjects were 29 Caucasian male-to-female transsexuals and 229 healthy male controls. Transsexuals differed from controls with respect to the mean length of the ERbeta repeat polymorphism, but not with respect to the length of the other two studied polymorphisms. However, binary logistic regression analysis revealed significant partial effects for all three polymorphisms, as well as for the interaction between the AR and aromatase gene polymorphisms, on the risk of developing transsexualism. Given the small number of transsexuals in the study, the results should be interpreted with the utmost caution. Further study of the putative role of these and other sex steroid-related genes for the development of transsexualism may, however, be worthwhile.  相似文献   
74.
A hydrophobic grid membrane filter-colony hybridization (HGMF-CH) method for the enumeration and isolation of cpe gene-carrying (cpe-positive) Clostridium perfringens spores from feces was developed. A 425-bp DNA probe specific for the cpe gene was sensitive and specific when tested with bacterial DNA and pure cultures. The enumeration of cpe-positive C. perfringens by the HGMF-CH method proved to be as sensitive as nested PCR combined with the most-probable number technique when tested with fecal samples from healthy individuals. With the aid of the HGMF-CH method, positive hybridization signals were detected from two out of seven fecal samples obtained from healthy individuals. Furthermore, cpe-positive C. perfringens was successfully isolated from both of these samples. The detection of cpe-positive C. perfringens by the HGMF-CH method is dependent on the ratio of cpe-positive C. perfringens colonies to total C. perfringens colonies growing on the HGMF-tryptose-sulfite-cycloserine plate. cpe-positive C. perfringens could be isolated if the ratio of cpe-positive C. perfringens spores to total C. perfringens spores was 6 x 10(-5) or higher. The HGMF-CH method provides an aid in the investigation of fecal samples of patients suffering from food poisoning or other diseases caused by cpe-positive C. perfringens. The method also offers a new approach in the investigation of the epidemiology of cpe-positive C. perfringens strains.  相似文献   
75.
Tuomilehto J  Hu G  Bidel S  Lindström J  Jousilahti P 《JAMA》2004,291(10):1213-1219
Context  Only a few studies of coffee consumption and diabetes mellitus (DM) have been reported, even though coffee is the most consumed beverage in the world. Objective  To determine the relationship between coffee consumption and the incidence of type 2 DM among Finnish individuals, who have the highest coffee consumption in the world. Design, Setting, and Participants  A prospective study from combined surveys conducted in 1982, 1987, and 1992 of 6974 Finnish men and 7655 women aged 35 to 64 years without history of stroke, coronary heart disease, or DM at baseline, with 175 682 person-years of follow-up. Coffee consumption and other study parameters were determined at baseline using standardized measurements. Main Outcome Measures  Hazard ratios (HRs) for the incidence of type 2 DM were estimated for different levels of daily coffee consumption. Results  During a mean follow-up of 12 years, there were 381 incident cases of type 2 DM. After adjustment for confounding factors (age, study year, body mass index, systolic blood pressure, education, occupational, commuting and leisure-time physical activity, alcohol and tea consumption, and smoking), the HRs of DM associated with the amount of coffee consumed daily (0-2, 3-4, 5-6, 7-9, =" BORDER="0">10 cups) were 1.00, 0.71 (95% confidence interval [CI], 0.48-1.05), 0.39 (95% CI, 0.25-0.60), 0.39 (95% CI, 0.20-0.74), and 0.21 (95% CI, 0.06-0.69) (P for trend<.001) in women, and 1.00, 0.73 (95% CI, 0.47-1.13), 0.70 (95% CI, 0.45-1.05), 0.67 (95% CI, 0.40-1.12), and 0.45 (95% CI, 0.25-0.81) (P for trend = .12) in men, respectively. In both sexes combined, the multivariate-adjusted inverse association was significant (P for trend <.001) and persisted when stratified by younger and older than 50 years; smokers and never smokers; healthy weight, overweight, and obese participants; alcohol drinker and nondrinker; and participants drinking filtered and nonfiltered coffee. Conclusion  Coffee drinking has a graded inverse association with the risk of type 2 DM; however, the reasons for this risk reduction associated with coffee remain unclear.   相似文献   
76.
77.
The hepatic detoxification system in Baltic flounder and rainbow trout was characterized under experimental conditions. Fish were exposed to benzo[a]pyrene (BaP, 10 and 50mg/kg, ip) or vehicle for 2, 5, and 10 days (in rainbow trout also for 20 days) and then sacrificed. Control fish were sampled at days 0 and 10 (flounder) or day 20 (rainbow trout). The hepatic distribution of CYP1A was analyzed immunohistochemically and microsomal ethoxyresorufin O-deethylase activity was determined spectrophotometrically. The kinetics of the CYP1A responses (EROD) was similar in both species, while a species-specific difference in the magnitude of the response was observed. CYP1A was demonstrated in the hepatocytes in both fish species 2 days after BaP administration and throughout the experiment. In rainbow trout a CYP1A response in the vascular endothelium of liver parenchyma was detected 2 days postadministration, while the corresponding reaction in flounder was seen 5 days postadministration. Thus, our results confirm previous reports that the CYP1A response is species specific. Furthermore, the induction of hepatic CYP1A in Baltic flounder reflects pathophysiological effects induced by polycyclic aromatic hydrocarbon compounds and, consequently, is a parameter useful when monitoring the anthropogenic effects on the Baltic Sea environment.  相似文献   
78.
We describe the synthesis and antibacterial properties of a novel antimicrobial peptidyl derivative, (2S)-2-(Nalpha-benzyloxycarbonyl-arginyl-leucylamido-1-[(E)-cinnamoylamido]-3-methylbutane, structurally based upon the inhibitory centre of the human cysteine protease inhibitor, cystatin C. The derivative, here called Cystapep 1, displayed antibacterial activity against several clinically important gram-positive bacteria. It displayed minimal inhibitory and bactericidal concentrations of about 16 microg/ml for both Staphylococcus aureus and Streptococcus pyogenes. In radial agar diffusion assays, groups A, B, C and G streptococci as well as staphylococci were generally susceptible to the action of Cystapep 1, whereas pneumococci and enterococci were less susceptible. No activity against gram-negative bacteria was observed. Cystapep 1 also showed high activity against methicillin-resistant S. aureus (MRSA) and multiantibiotic-resistant coagulase-negative staphylococci (CNS), suggesting that its mechanism of action differs from those of most currently used antibiotics.  相似文献   
79.
AIM: Oliguria is seen during elevated intraperitoneal pressure, but the physiological mechanisms are not yet clarified. The purpose of the present study was to investigate the changes in renal function, cardiac output and distribution of systemic blood flow (BF) that occur in connection with an elevation of intra-abdominal pressure (IAP) in a rat model by isotope-labelled microsphere technique. METHODS: A 5 or 10 mmHg IAP was created by CO2 insufflation and maintained for 90 min in anaesthetized and mechanically ventilated rats. Rats with normal IAP served as controls. Blood flow and cardiac output measurements by injection of isotope-labelled microspheres were conducted at three time points. Acid-base balance, urine output, glomerular filtration rate (GFR) and urinary excretion products were also followed. RESULTS: Glomerular filtration rate decreased [0.7-0.1 mL min(-1) g(-1) kidney weight (KW)] with elevated IAP, as did urine output (8.5-0.6 microL min(-1) g(-1) KW). Dramatic decreases were seen in renal excretion of sodium (by 97%), potassium (by 94%) and osmotic active substances (by 93%). Cardiac output was diminished by 54% at 5 mmHg and by 65% at 10 mmHg intraperitoneal pressure and systemic vascular resistance (SVR) was elevated threefold. CONCLUSION: Cardiac output, measured by microsphere technique, decreased during elevated intraperitoneal pressure by CO2 in anaesthetized rats, while SVR was elevated and renal excretory functions were decreased to a large extent.  相似文献   
80.
The aim of this study was to investigate whether differences in Ixodes ricinus (L.) nymphal relative density exist among different vegetation types in southern Sweden. Nymphal I. ricinus were sampled in southeastern Scania in southern Sweden during June-August 1997. A total of 110-180 25-m2 samples were taken by blanket-dragging from each of nine different vegetation types. There was a highly significant difference in nymphal abundance between the open areas as one group and the forested areas as another group (P < 0.0001). Vegetation types that differed significantly in median nymphal abundance from all other vegetation types were pine forest (16 nymphs/100 m2) and beech forest (40 nymphs/100 m2). No significant differences in median nymphal density were revealed among mixed deciduous forest, alder forest, oak forest, and hazel forest (28-32 nymphs/100 m2), or among dry meadow, meadow, and heath (0 nymphs/100 m2). Forestation of open areas is likely to lead to increased I. ricinus abundance and disease risk.  相似文献   
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