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121.
Pramilla Senanayake Dorine G. Kramer 《American journal of obstetrics and gynecology》1980,138(7):852-860
The dramatic increase in use of contraception worldwide makes it imperative to understand the effects of contraceptives on the health of women using them. In this article, we review the literature on the relationships of modern nonsurgical contraception with pelvic inflammatory disease. Subsequently, we identify areas where further research is needed to better define the risks and benefits of these contraceptive methods in various settings. From our review, two new conclusions emerge. First, our reanalysis of published data on the risk of PID associated with intrauterine device (IUD) use compared with no contraceptive use shows, with one exception, less risk than the previous comparisons to all non-IUD use. Second, and probably most importantly, the studies, when taken together, strongly imply that oral contraceptives have a protective effect against PID. Only one study of 11 is equivocal on this point. 相似文献
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H Collas M Delbarre P A De Preville P Courville C Neveu A Dompmartin X Balguerie B Lemaistre J C Rzeznik B Thiebot M C Boullie P Bravard Y Michel M Krug C Le Corvaisier-Pieto P Young E Thomine C Boivin J Ziade A Pellerin M F Hellot D Leroy P Lauret J Benichou P Joly 《Annales de dermatologie et de vénéréologie》1999,126(6-7):494-500
INTRODUCTION: The necessity of excising melanomas characterized by a slight thickness at an early stage, leads dermatologists to remove pigmented lesions which do not correspond to melanomas. The aims of this study were: a) to prospectively assess the accuracy of melanoma diagnosis, b) to quantify the number of excisions performed according to the degree of melanoma suspicion, c) to determine the specific clinical sign or signs of relevant diagnostic value. PATIENTS AND METHODS: This study was conducted prospectively from January 1996 to August 1997 by dermatologists in private practice and dermatologists from a University Hospital staff. When it was decided to excise a pigmented lesion, a form was filled out choosing the most appropriate clinical diagnosis, the degree of melanoma suspicion, and clinical signs which lead to surgery. Based on histological findings as the reference, the sensitivity, specificity, accuracy of melanoma diagnosis and the kappa test that evaluates the concordance between clinical and histological diagnosis, were performed. The diagnostic value of clinical signs was assessed by variance analysis. RESULTS: Of the 353 excised lesions, 38 (10.7 p. 100) were identified as melanoma on histologic examination. The sensitivity, the specificity and diagnostic accuracy were: 79 p. 100, 94 p. 100 and 53 p. 100 respectively. The kappa test concordance between clinical and histological diagnosis was 0.66. Two hundred and two lesions (57 p. 100) were excised even though the clinical suspicion of melanoma was poorly considered. Only one of these 202 lesions was identified histologically as a true melanoma. Thirty seven (24.5 p. 100) of the 151 remaining excised lesions with an "average" or "strong" suspicion were true melanomas. The clinical signs considered, alone or associated, had a poor predictive positive value (< 38 p. 100). An analytical approach performed with a logistic model permitted the identification of two associated signs suggesting a best diagnostic value. DISCUSSION: This is the only study, to our knowledge, reported in the literature which prospectively assesses the sensitivity, specificity and concordance between clinical and histological diagnosis of melanoma. Results were considered from average to good. The originality of this study was to assess the number of pigmented lesions excised according to the degree of melanoma suspicion, suggesting the possibility of reducing the number of nevi removed when the melanoma risk was considered clinically poor. Finally, this study emphasizes the limits of clinical semiology and the need for future diagnostic methods in the assessment of melanoma. 相似文献
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126.
Liversedge SP Rayner K White SJ Vergilino-Perez D Findlay JM Kentridge RW 《Vision research》2004,44(10):1013-1024
Readers' eye movements were monitored when they read either normal sentences or sentences with masked or disappearing text (in which the fixated word disappeared or was masked after 60 ms). The goals of the research were to investigate (1) whether a gap effect occurred in reading and (2) the influence of linguistic and visual factors on oculomotor control. The results of a number of global analyses of eye movements under disappearing text conditions clearly demonstrated that there is no gap effect in reading. However, comparative analyses across a number of local measures in the experiments indicated that cognitive/lexical processes, as well as the continual uptake of visual information, influence eye movement control during reading. A persistent visual object throughout fixation caused refixations and even when a fixated word had disappeared (or been masked), there were significant effects of word frequency and word length. 相似文献
127.
The hepatic peptide hormone hepcidin is the central regulator of iron metabolism and mediator of anemia of inflammation. To date, only one specific immuno-dot assay to measure hepcidin in urine had been documented. Here we report an alternative approach for quantification of hepcidin in urine by surface-enhanced laser desorption/ionization time-of-flight mass spectrometry (SELDI-TOF-MS). Peptide peaks were detected corresponding to the 3 forms of hepcidin normally found in urine. The identity of the peptide peak equivalent to hepcidin-25 was confirmed using synthetic human hepcidin-25. Validation of our MS data on samples with various hepcidin levels showed a strong correlation with previous immuno-dot assay results (Spearman R = 0.9275, P < .001). Most importantly, this hepcidin assay clearly discriminates between relevant clinical iron disorders. In conclusion, this novel MS urine hepcidin assay is easy to perform and available to a wide audience. This enables the implementation of hepcidin measurements in large clinical studies. 相似文献
128.
Can endobronchial biopsy analysis be recommended to discriminate between asthma and COPD in routine practice?
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BACKGROUND: International guidelines stress the importance of accurately discriminating between asthma and chronic obstructive pulmonary disease (COPD). Although characteristic pathological features have been described for both conditions, their discriminatory power has never been systematically assessed. METHODS: Endobronchial biopsy (EBB) specimens from patients with a clear clinical diagnosis of asthma and COPD (50 per group) were examined by three pathologists in a double blind manner. They were asked to propose a pathological diagnosis of either asthma or COPD and to analyse qualitatively the most frequent abnormalities reported in the literature. RESULTS: The sensitivity and specificity of EBB ranged from 36% to 48% and from 56% to 79%, respectively. Eosinophils strongly biased the pathological diagnoses in favour of asthma, whereas their estimated prevalence was similar (11-37% in asthma and 13-41% in COPD). Metaplasia (11-39% in COPD, 1-18% in asthma) and epithelial inflammation (28-61% in COPD, 11-38% in asthma) tended to be specific to COPD, whereas epithelial desquamation (80-98% in asthma, 61-88% in COPD) and basement membrane thickening (71-94% in asthma, 53-88% in COPD) tended to be associated with asthma. There was acceptable intra- and inter-observer agreement only for metaplasia and epithelial eosinophils. CONCLUSIONS: Specific histopathological features of asthma and COPD probably exist, but current routine analysis procedures to assess EBB specimens are not sufficiently discriminatory. This might be rectified by improving pathological definitions. 相似文献
129.
Cunningham TJ Jing H Akerblom I Morgan R Fisher TS Neveu M 《Experimental neurology》2002,177(1):32-39
We identified the human cDNA encoding a peptide that has been partially purified from the secretions of oxidatively stressed neural cell lines, murine adenocarcinoma cells, and group Abeta-hemolytic steptococci. We then genetically modified mouse and human neural cells to overexpress this peptide and found these modified cells to be remarkably hearty, surviving under conditions of severe oxidative stress, in xenocultures when exposed to activated macrophages, and as xenografts in the brain of rats that were not immunosuppressed. The peptide is called DSEP (dee-sep) for diffusible survival evasion peptide. Part of the survival advantage of DSEP overexpressors may be due to their attenuated response to all-trans-retinoic acid, which regulates differentiation and apoptosis of several cell types including neural and immune cells. 相似文献
130.
Vitamin and homocysteine status of mothers and infants and the risk of nonsyndromic orofacial clefts
van Rooij IA Swinkels DW Blom HJ Merkus HM Steegers-Theunissen RP 《American journal of obstetrics and gynecology》2003,189(4):1155-1160
OBJECTIVE: This study was undertaken to investigate the involvement of maternal and infant B vitamins and homocysteine as risk factors for orofacial clefting. STUDY DESIGN: Venous blood samples were taken from 96 infants with nonsyndromic orofacial clefts and 88 infants without a congenital malformation and from their mothers at approximately 14 months after the index pregnancy. Red blood cell and serum folate, serum vitamin B(12), whole blood vitamin B(6) as pyridoxal-5'-phosphate (PLP), and plasma homocysteine concentrations were measured. RESULTS: A vitamin B(12) concentration of 185 pmol/L or less and a PLP concentration of 44 nmol/L or less in mothers increased the risk of having a child with an orofacial cleft (odds ratio [OR]=3.1; 95% CI: 1.3-7.4, OR=2.9; 95% CI: 1.2-7.1, respectively). Infants with orofacial clefts had a 15% lower serum folate concentration compared with controls (P=.06). CONCLUSION: A low vitamin B(12) and PLP concentration in mothers increased the risk of orofacial clefts in the offspring. A possible role of the infant's folate status is suggested. 相似文献