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551.
Joro R Lääperi AL Soimakallio S Järvenpää R Kuukasjärvi T Toivonen T Saaristo R Dastidar P 《Journal of medical engineering & technology》2008,32(4):325-335
Five combinations of image-processing algorithms were applied to dynamic infrared (IR) images of six breast cancer patients preoperatively to establish optimal enhancement of cancer tissue before frequency analysis. mid-wave photovoltaic (PV) IR cameras with 320x254 and 640x512 pixels were used. The signal-to-noise ratio and the specificity for breast cancer were evaluated with the image-processing combinations from the image series of each patient. Before image processing and frequency analysis the effect of patient movement was minimized with a stabilization program developed and tested in the study by stabilizing image slices using surface markers set as measurement points on the skin of the imaged breast. A mathematical equation for superiority value was developed for comparison of the key ratios of the image-processing combinations. The ability of each combination to locate the mammography finding of breast cancer in each patient was compared. Our results show that data collected with a 640x512-pixel mid-wave PV camera applying image-processing methods optimizing signal-to-noise ratio, morphological image processing and linear image restoration before frequency analysis possess the greatest superiority value, showing the cancer area most clearly also in the match centre of the mammography estimation. 相似文献
552.
The circumstances of diagnosis of human pasteurellosis are reviewed. The diagnosis is usually suspected for animal bite or scratch wounds. Conversely, in other infections the diagnosis is only based on bacteriological data. Phenotypic misidentification of Pasteurellaceae from clinical material is common. The phenotypic criteria of identification of the six species of human pathogen Pasteurella are presented. We emphasise that bite wound specimens have to be cultured for aerobic and anaerobic bacteria and yield an average of 5 bacterial isolates per culture. Antibiotic therapy relies upon amino-penicillins or cephalosporins, although b-lactamase producing strains are scarce. Fluoroquinolones can be an alternative for systemic infections. Molecular typing unequivocally points out the risk of transmission from pets to humans. Immunocompromised persons have to be made aware of precautions. 相似文献
553.
Taponen S Ahonkallio S Martikainen H Koivunen R Ruokonen A Sovio U Hartikainen AL Pouta A Laitinen J King V Franks S McCarthy MI Järvelin MR 《Human reproduction (Oxford, England)》2004,19(5):1083-1088
BACKGROUND: The aim of this study was to investigate the prevalence of polycystic ovaries (PCO) among women with self-reported oligomenorrhoea and/or hirsutism and to see whether women with symptoms and PCO have less favourable levels of biochemical markers than controls or women with symptoms and normal ovaries. METHODS: The ultrasonographic ovarian morphology and the hormonal and metabolic profile of female cases with self-reported symptoms typical of polycystic ovary syndrome (PCOS) (n = 196) and asymptomatic controls (n = 67) at the age of 31 years were examined in a general population-based Northern Finland Birth Cohort 1966. RESULTS: The prevalence of PCO (37.3 versus 18.2%; P = 0.004) was significantly higher in the cases (oligomenorrhoea and/or hirsutism) than in the controls. PCO morphology was detected in 18.4% of those who reported only hirsutism, in 47.9% of those reporting only oligomenorrhoea, and in 70.4% of those reporting both symptoms. In the cases with PCO compared to (i) the controls and (ii) the cases without PCO, body mass index (P = 0.026 and P = 0.011), ovarian volume [right P = 0.001, left P = 0.208 (non-significant) and right P < 0.001, left P = 0.022], mean follicle number (P < 0.001 and P < 0.001), testosterone (P = 0.063 and P = 0.029), free androgen index (P = 0.007 and P = 0.013) and insulin (P = 0.033 and P = 0.040) were higher, and sex hormone-binding globulin (P = 0.039 and P = 0.068) and glucose:insulin ratio (P = 0.060 and P = 0.054) lower. Cases with PCO also had higher waist:hip ratio (P = 0.011), infertility rate (P = 0.005) and glucose (P = 0.045) and lower insulin-like growth factor-binding protein-1 (P = 0.012) than controls. The clinical, hormonal and metabolic characteristics did not differ significantly between cases without PCO and controls with the exception of infertility rate, which was significantly higher in the cases without PCO (26.4 vs. 10.0%; P = 0.009). CONCLUSIONS: In a general population, women with symptoms of oligomenorrhoea and/or hirsutism more often have PCO than asymptomatic women. Levels of biochemical and clinical markers in symptomatic women with PCO differed from and were less favourable than those in symptomatic women without PCO or asymptomatic women, implying an increased risk for health. 相似文献
554.
Marsollier L Aubry J Saint-André JP Robert R Legras P Manceau AL Bourdon S Audrain C Carbonnelle B 《Pathologie-biologie》2003,51(8-9):490-495
Mycobacterium ulcerans is an environmental pathogen concerning mainly the tropical countries; it is the causative agent of Buruli ulcer, which has become the third most important mycobacterial disease. In spite of water-linked epidemiological studies to identify the sources of M. ulcerans, the reservoir and the mode of transmission of this organism remain elusive. To determine the ecology and the mode of transmission of M. ulcerans we have set up an experimental model. This experimental model demonstrated that water bugs were able to transmit M. ulcerans by bites. In insects, the bacilli were localized exclusively within salivary glands, where it could both multiply contrary to other mycobacteria species. In another experimental study, we report that the crude extracts from aquatic plants stimulate in vitro the growth of M. ulcerans as much as the biofilm formation by M. ulcerans has been observed on aquatic plants. Given that the water bugs are essentially carnivorous, it is difficult to imagine a direct contact in the contamination of aquatic bugs and plants. It seems very likely that an intermediate host exists. In an endemic area of Daloa in C?te d'Ivoire, our observations were confirmed. 相似文献
555.
Germline and de novo mutations in the HRPT2 tumour suppressor gene in familial isolated hyperparathyroidism (FIHP) 总被引:2,自引:1,他引:2 下载免费PDF全文
556.
Defective opsonization of Haemophilus influenzae by sera of elderly patients. 总被引:1,自引:0,他引:1 下载免费PDF全文
The elderly are prone to respiratory infection but the role of disordered immunity is uncertain. Opsonization of bacteria is an important early host defence mechanism required for optimal phagocytosis. There are conflicting reports in the literature as to the ability of the elderly to perform this function and one reason may be the use of in vitro tests in which the 'target' microorganism is clinically unrealistic. We have tested the hypothesis that use of a more clinically relevant microorganism Haemophilus influenzae, which commonly infects the respiratory tract of such persons, may detect abnormalities of opsonization in the elderly. Using an in vitro luminol-enhanced chemiluminescence (CL) assay we have compared sera from 45 elderly subjects (age greater than 70 years without known immune deficiency or current infection) with sera from 12 young, healthy subjects, for their capacity to opsonize Staphylococcus aureus (Oxford strain) and H. influenzae (non-capsulated) expressed as percentage CL obtained using pooled normal human serum (PNHS). There was no significant difference (median) between the elderly (95%) and the young (108%) with regard to S. aureus but opsonization of H. influenzae was poor in the elderly (63%) compared with that in the younger group (87%; P = 0.002); the sera of 11 elderly subjects having an opsonic capacity less than 30% that of PNHS. We conclude that use of the more clinically relevant microorganism, H. influenzae, appears to differentiate a subgroup of the elderly with reduced serum opsonic capacity. It remains to be determined prospectively whether these individuals are in fact more prone to infection. 相似文献
557.
Lee DS Park J Kay KA Christakis NA Oltvai ZN Barabási AL 《Proceedings of the National Academy of Sciences of the United States of America》2008,105(29):9880-9885
Most diseases are the consequence of the breakdown of cellular processes, but the relationships among genetic/epigenetic defects, the molecular interaction networks underlying them, and the disease phenotypes remain poorly understood. To gain insights into such relationships, here we constructed a bipartite human disease association network in which nodes are diseases and two diseases are linked if mutated enzymes associated with them catalyze adjacent metabolic reactions. We find that connected disease pairs display higher correlated reaction flux rate, corresponding enzyme-encoding gene coexpression, and higher comorbidity than those that have no metabolic link between them. Furthermore, the more connected a disease is to other diseases, the higher is its prevalence and associated mortality rate. The network topology-based approach also helps to uncover potential mechanisms that contribute to their shared pathophysiology. Thus, the structure and modeled function of the human metabolic network can provide insights into disease comorbidity, with potentially important consequences for disease diagnosis and prevention. 相似文献
558.
Body size from birth to adulthood as a predictor of self-reported polycystic ovary syndrome symptoms
Laitinen J Taponen S Martikainen H Pouta A Millwood I Hartikainen AL Ruokonen A Sovio U McCarthy MI Franks S Järvelin MR 《International journal of obesity (2005)》2003,27(6):710-715
OBJECTIVE: To study the association between body size from birth to adulthood and self-reported symptoms of polycystic ovary syndrome (PCOS), particularly hirsutism and menstrual disturbances. DESIGN: Longitudinal, population-based study of a cohort of women born in 1966 in northern Finland. The study population included 2007 women who were not pregnant and did not use hormonal contraception. Of these 528 (26%) had self-reported symptoms of PCOS. RESULTS: Weight at birth, gestational age, being small for gestational age or growth retardation at birth were not associated with PCOS symptoms at 31 y. An increased risk of PCOS symptoms was observed among women with abdominal obesity (waist/hip ratio >85th percentile) at 31 y who had normal weight in adolescence and were overweight (body mass index (BMI) 25.0-29.9 kg/m(2)) or obese (BMI>30.0 kg/m(2)) at 31 y (relative risk (RR) (95% CI) 1.44(1.10-1.89)), and among women with abdominal obesity who were overweight or obese at both 14 and 31 y (1.71 (1.30-2.24)). A total of 30% and 41% of the women with PCOS symptoms in these groups could be attributed, respectively, to overweight, obesity and abdominal obesity at 31 y. CONCLUSIONS: These results suggest that obesity in adolescence and in adulthood, and also weight gain after adolescence, particularly in the presence of abdominal obesity, are associated with self-reported PCOS symptoms in adulthood. Thus, based on the results from intervention studies treating PCOS and the results of this study, the prevention of obesity and abdominal obesity is important among young women. 相似文献
559.
Jia AL Ding XQ Chen DL Chao ZZ Liu ZY Chao RB 《Journal of Asian natural products research》2008,10(1-2):105-109
A new indole alkaloid, named donasine, has been isolated from the rhizomes of Arundo donax L. Its structure was determined by X-ray crystallographic analysis and spectral methods. The primary pharmacological test showed that the compound has an action of reducing fever. 相似文献
560.
Determining the apical terminus of root-end resected teeth using three modern apex locators: a comparative ex vivo study 总被引:4,自引:0,他引:4
AIM: To assess ex vivo the accuracy of various electronic apex locators in locating the apical terminus of root-end resected teeth. METHODOLOGY: Ninety extracted human posterior teeth (182 root canals) were prepared to a minimum size of 40 and filled with gutta-percha and sealer. After resection of the apical 3 mm of the root, the root canal filling was removed using HERO rotary instruments. The size of the root canal at the apical terminus after removal of the filling ranged from size 50 to 90. The root canal length to the apical terminus was determined using 3 apex locators (Root ZX, Raypex4 and Apex Pointer). A new mounting model that utilized a micrometer was used to perform the measurements and to visually determine the actual position of the apical terminus. The frequency of locating the apical terminus and the corresponding 95% confidence interval (CI) were calculated. Additionally, the coefficient of repeatability of each apex locator and the limits of inter-operator agreement were determined. RESULTS: All apex locators showed an acceptable repeatability (0.02-0.03 mm coefficient of repeatability) and narrow limits of inter-operator agreement (+0.07 and -0.07 mm). The accuracy of determining the apical terminus within 1 mm in the root canal was as follows: Root ZX 90% (164/182 root-canals) [95%CI: 86-94%], Raypex4 74% (135/182 root-canals) [95%CI: 68-80%], and Apex Pointer 71% (129/182 root canals) [95%CI: 65-77%]. No over-instrumentation resulted when the Root ZX device was used. In contrast, using the Raypex4 or the Apex Pointer device resulted in over-instrumentation in 8 of 182 root canals (4%). CONCLUSIONS: Under the conditions of this study all three apex locators were able to detect the apical terminus of root-end resected teeth with an acceptable range. The Root ZX device was the most accurate without over-instrumentation of the root canals. 相似文献