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71.
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
72.
Direct identification of gram-positive cocci from routine blood cultures by using AccuProbe tests 下载免费PDF全文
Rapid and reliable identification of bacteria directly from blood cultures is important in clinical practice to guide appropriate antibiotic therapy. In this study, the performance of the AccuProbe (Gen-Probe, Inc., San Diego, Calif.) in direct identification of Staphylococcus aureus, Streptococcus pneumoniae, enterococci, and group A and B streptococci from positive blood culture bottles was evaluated by using 6-year routine clinical laboratory blood culture material from Paijat-Hame Central Hospital, Lahti, Finland. With the enterococcal and group A and B streptococcal probes, the diagnostic performance of the test was excellent at a cutoff value of 50,000 relative light units (RLU) as recommended by the manufacturer. However, with the S. aureus probe, although the specificity was very high (99.8%), the sensitivity was low (72.4%). To improve the clinical usability of the direct AccuProbe identification, optimal cutoff values for the individual AccuProbe tests were defined by using receiver-operating characteristic analysis. Consequently, cutoff values for S. aureus and S. pneumoniae tests were adjusted to 30,000 RLU and for enterococci and to 55,000 RLU for group A and B streptococci. With these adjustments, the performance of the AccuProbe tests, especially that for S. aureus, was significantly improved. 相似文献
73.
Lindström M Nevas M Kurki J Sauna-aho R Latvala-Kiesilä A Pölönen I Korkeala H 《Journal of clinical microbiology》2004,42(10):4718-4725
The largest reported outbreak of type C botulism in fur production animals is described. Epidemiological investigation of 117 out of 157 (response rate, 74.5%) farms revealed that 44,130 animals died or were euthanized, while 8,033 animals with milder symptoms recovered. The overall death rate in all animals at risk was 21.7%. The death rates were significantly higher in blue and shadow foxes (24.2 and 27.8%, respectively) than in silver and blue silver foxes and minks (below 4%). All minks had been immunized against botulinum toxin type C. Deaths were associated with feed manufactured by a local processor, 83 of whose customer farms (70.9%) reported dead or sick animals. Five feedlots out of 19 delivered to the farms on the day preceding the onset of the outbreak (day 2) were associated with a death rate higher than 40%. These feedlots consisted of fresh feed processed on day 2 and feed processed 1 day earlier (day 1). In laboratory analysis, the day 2 feed contained botulinum toxin type C (>600 minimum lethal doses/g), while the day 1 feed did not contain toxin. Toxin was not detected in feed raw-material samples. Clostridium botulinum type C was detected by PCR in some feed components and in feed. However, as the feed temperature was continuously 8 degrees C or below and the pH was continuously 5.6 or below according to the manufacturer, it seems unlikely that spore germination and toxin formation occurred during overnight storage. Hence, the events leading to toxin formation were not determined. 相似文献
74.
Alm JJ Heino TJ Hentunen TA Väänänen HK Aro HT 《Tissue engineering. Part C, Methods》2012,18(9):658-666
The development of in vitro culturing techniques for osteoblastic differentiation of human mesenchymal stem cells (hMSC) is important for cell biology research and the development of tissue-engineering applications. Dexamethasone (Dex) is a commonly used supplement, but the optimal use of Dex treatment is still unclear. By adjusting the timing of Dex supplementation, the negative effects of long-term Dex treatment could be overcome. Transient Dex treatment could contribute toward minimizing broad donor variation, which is a major challenge. We compared the two most widely used Dex concentrations of 10 and 100?nM as transient or continuous treatment and studied inter- and intraindividual variations in osteoblastic differentiation of hMSC. Characterized bone marrow-derived hMSC from 17 female donors of different age groups were used. During osteoblastic induction, the cells were treated with 10 or 100?nM Dex either transiently for different time periods or continuously. Differentiation was evaluated by measuring alkaline phosphatase (ALP) activity and staining for ALP, von Kossa, collagen type I, and osteocalcin. Cell proliferation, cell viability, and apoptosis were also monitored. The strongest osteoblastic differentiation was observed when 100?nM Dex was present for the first week. In terms of inter- and intraindividual coefficients of variations, transient treatment with 100?nM Dex was superior to the other culture conditions and showed the lowest variations in all age groups. This study demonstrates that the temporary presence of 100?nM Dex during the first week of induction culture promotes hMSC osteoblastic differentiation and reduces inter- and intraindividual variations. With this protocol, we can reproducibly produce functional osteoblasts in vitro from the hMSC of different donor populations. 相似文献
75.
K. Kuuliala A. Kuuliala M. Hmlinen R. Koivuniemi H. Kautiainen E. Moilanen H. Repo M. Leirisalo‐Repo 《Scandinavian journal of immunology》2017,85(2):155-161
It has been proposed that the Akt kinase pathway provides a regulatory mechanism to limit the inflammatory response. We examined the activation of Akt upon lipopolysaccharide (LPS) challenge in monocytes of patients with rheumatoid arthritis (RA) and correlated it with disease activity. Twelve subjects with recent‐onset, DMARD‐naïve RA, thirteen patients with chronic, DMARD therapy–non‐responding RA and 27 healthy volunteers provided whole blood samples for phosphospecific flow cytometric measurement of unstimulated and LPS‐stimulated Akt phosphorylation at serine 473 in monocytes, determined in relative fluorescence units (RFU). Activation capability, that is responsiveness of monocytes, was determined as the difference between stimulated and unstimulated samples and compared between groups using Mann–Whitney test. CRP and ESR, swollen and tender joint counts, patients’ global assessment of disease activity, DAS28 score and plasma IL‐6 determined by ELISA were correlated with Akt activation using Spearman method. Median (interquartile range) Akt activation capability was significantly lower in DMARD‐naïve (379 RFU [285, 432], P = 0.016) and even lower in DMARD‐non‐responding RA (258 RFU [213, 338], P < 0.001), compared to healthy controls (505 RFU[408, 639]) and showed a negative correlation with swollen joint count (r = −0.48, CI −0.78 to −0.05, P = 0.014), CRP (r = −0.42, CI −0.80 to −0.02, P = 0.039) and plasma IL‐6 levels (r = −0.44, CI −0.65 to −0.17, P = 0.001). In conclusion, Akt activation capability of monocytes is low in early untreated RA and even lower in chronic, DMARD‐non‐responding RA, suggesting a role for Akt pathway in the pathogenesis of RA. 相似文献
76.
Xingchen Wu Seyoum Nerisho Prasun Dastidar Pertti Ryymin Ritva Järvenpää Hannu Pertovaara Hannu Eskola Pirkko‐Liisa Kellokumpu‐Lehtinen 《NMR in biomedicine》2013,26(9):1186-1194
To compare different MRI sequences for the detection of lesions and the evaluation of response to chemotherapy in patients with diffuse large B‐cell lymphoma (DLBCL), 18 patients with histology‐confirmed DLBCL underwent 3‐T MRI scanning prior to and 1 week after chemotherapy. The MRI sequences included T1‐weighted pre‐ and post‐contrast, T2‐weighted with and without fat suppression, and a single‐shot echo‐planar diffusion‐weighted imaging (DWI) with two b values (0 and 800 s/mm2). Conventional MRI sequence comparisons were performed using the contrast ratio between tumor and normal vertebral body instead of signal intensity. The apparent diffusion coefficient (ADC) of the tumor was measured directly on the parametric ADC map. The tumor volume was used as a reference for the evaluation of chemotherapy response. The mean tumor volume was 374 mL at baseline, and decreased by 65% 1 week after chemotherapy (p < 0.01). The T2‐weighted image with fat suppression showed a significantly higher contrast ratio compared with images from all other conventional MRI sequences, both before and after treatment (p < 0.01, respectively). The contrast ratio of the T2‐weighted image with fat suppression decreased significantly (p < 0.01), and that of the T1‐weighted pre‐contrast image increased significantly (p < 0.01), after treatment. However, there was no correlation between the change in contrast ratio and tumor volume. The mean ADC value was 0.68 × 10–3 mm2/s at baseline; it increased by 89% after chemotherapy (p < 0.001), and the change in ADC value correlated with the change in tumor volume (r = 0.66, p < 0.01). The baseline ADC value also correlated inversely with the percentage change in ADC after treatment (r = ?0.62, p < 0.01). In conclusion, this study indicates that T2‐weighted imaging with fat suppression is the best conventional sequence for the detection of lesions and evaluation of the efficacy of chemotherapy in DLBCL. DWI with ADC mapping is an imaging modality with both diagnostic and prognostic value that could complement conventional MRI. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
77.
Tourula M Fukazawa T Isola A Hassi J Tochihara Y Rintamäki H 《European journal of applied physiology》2011,111(4):633-640
It is a common practice in Northern countries that children aged about 2 weeks to 2 years take their daytime sleep outdoors
in prams in winter. The aim was to evaluate the thermal insulation of clothing of infants sleeping outdoors in winter. Clothing
data of infants aged 3.5 months was collected, and sleep duration, skin and microclimate temperatures, humidity inside middle
wear, air temperature and velocity of the outdoor environment were recorded during sleep taken outdoors (n = 34) and indoors (n = 33) in families’ homes. The insulation of clothing ensembles was measured by using a baby-size thermal manikin, and the
values were used for defining clothing insulation of the observed infants. Required clothing insulation for each condition
was estimated according to ISO 11079. Clothing insulation did not correlate with ambient air temperature. The observed and
required insulation of the study group was equal at about −5°C, but overdressing existed in warmer and deficiency in thermal
insulation in colder temperatures (r
s 0.739, p < 0.001). However, even at −5°C a slow cooling (ca. 0.012°C/min) of mean skin temperature (T
sk) was observed. When the difference between observed and required insulation increased, the cooling rate of T
sk increased linearly (r
s 0.605, p < 0.001) and the infants slept for a shorter period (r
s 0.524, p = 0.001). The results of this study show the difficulty of adjusting systematically the optimal thermal insulation for outdoor
sleeping infants during northern winter. Therefore, the necessity for guidelines is obvious. The study provides information
for adequate cold protection of infants sleeping in cold conditions. 相似文献
78.
Paajanen H Syvähuoko I Airo I 《Surgical laparoscopy, endoscopy & percutaneous techniques》2004,14(4):215-218
Sportsman's hernia is a term used to describe a weakness or disruption of is a term used to describe the musculotendinous part of the posterior inguinal wall, which causes persistent groin pain in athletes. A video-assisted placement of extraperitoneal synthetic mesh to support the damaged area may heal this injury. Forty-one male athletes at an elite level (mean age 27 +/- 7.1 years) with chronic groin pain, which was resistant to conservative therapy, were referred to surgery by sports clinics or club doctors. The majority of the patients were soccer (58%) or ice hockey players (27%) at a professional level. A 10 x 15 cm polypropylene mesh was placed into the preperitoneal space using a totally extraperitoneal video-assisted technique. The severity of pain, and the time to return to sports, were determined after 1 month and after the mean follow-up of 4 years. On operation, no macroscopic abnormality was found in 24 patients (58%), obvious musculotendinous tear was present in 10 patients, and muscle asymmetry was present in 7 patients. All except 2 patients (95%) returned to their sport activities after 1 month of convalescence. No immediate or long-term complications were associated with the operation. The placement of a retropubic mesh was safe and a mini-invasive method to repair sportsman's hernia and chronic groin pain of athletes. 相似文献
79.
Kari Rantavuori Satu Lahti Hannu Hausen Liisa Seppä Sakari Kärkkäinen 《Acta odontologica Scandinavica》2013,71(4):207-213
Objectives: Our aim was to describe the occurrence of dental fear among Finnish children of different ages and to ascertain how oral health and family characteristics are associated with dental fear. Methods: The subject groups were aged 3, 6, 9, 12, and 15 years in two middle‐sized cities, and the 1474 participants were distributed over fairly equal samples of each age. A questionnaire given to each child to be filled out at home enquired about social background, oral hygiene habits, diet, and dental fear. Oral health status was examined clinically and radiographically by two calibrated dentists. Multiple logistic regression analyses were performed for each age group in order to study the associations between dental fear and selected factors. Results: Dental fear was higher among 12‐ and 15‐year‐old children than among the younger ones. Pain, drilling, and local anesthesia were reported to be the most frightening aspects. Excluding the 12‐year‐olds, children whose family members reported dental fear were more likely to report dental fear than children whose family members did not report dental fear. Six‐ and 12‐year‐olds who had experienced caries were more likely to report dental fear than were caries‐free children. Among 6‐year‐olds, father's education modified the effect of a child's caries experience on child dental fear. Frequent intake of sugary items and a limit on eating candies to only one day per week were associated with higher dental fear. Conclusions: Fear of dental treatment is still fairly common among Finnish children, and the factors associated with it differ with the age of the child. 相似文献
80.
Sari Castrén Caroline E. Temcheff Jeffrey Derevensky Kim Josefsson Hannu Alho Anne H. Salonen 《International journal of mental health and addiction》2017,15(2):295-311
Empirical evidence has shown that youth gamble on both regulated and unregulated games, despite legislative prohibitions. This study assesses middle and high school teachers’ awareness and attitudes regarding adolescent gambling and other potentially high-risk behaviours in Finland. A convenience sample of teachers (N?=?157) from 13 provinces participated in the survey. The results suggest that teachers in Finland were more knowledgeable of the age limits of other adolescent high-risk behaviours than the legal age for gambling. Teachers were somewhat familiar with the behaviours and consequences associated with adolescent gambling. All other risk behaviours were perceived as being more important than gambling. Teachers’ awareness about gambling prevention material in Finnish schools was limited. Results suggest that initiatives are required to enhance teachers’ knowledge of adolescent problem gambling and its harmful short- and long-term consequences. School policies and guidelines including gambling behavior should be implemented in middle and high schools globally. 相似文献