全文获取类型
收费全文 | 1123篇 |
免费 | 40篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 9篇 |
儿科学 | 35篇 |
妇产科学 | 39篇 |
基础医学 | 118篇 |
口腔科学 | 22篇 |
临床医学 | 79篇 |
内科学 | 243篇 |
皮肤病学 | 28篇 |
神经病学 | 150篇 |
特种医学 | 39篇 |
外科学 | 89篇 |
综合类 | 2篇 |
预防医学 | 97篇 |
眼科学 | 8篇 |
药学 | 89篇 |
中国医学 | 8篇 |
肿瘤学 | 114篇 |
出版年
2024年 | 1篇 |
2023年 | 11篇 |
2022年 | 44篇 |
2021年 | 47篇 |
2020年 | 15篇 |
2019年 | 27篇 |
2018年 | 47篇 |
2017年 | 29篇 |
2016年 | 38篇 |
2015年 | 44篇 |
2014年 | 55篇 |
2013年 | 64篇 |
2012年 | 108篇 |
2011年 | 105篇 |
2010年 | 60篇 |
2009年 | 41篇 |
2008年 | 74篇 |
2007年 | 48篇 |
2006年 | 68篇 |
2005年 | 63篇 |
2004年 | 51篇 |
2003年 | 41篇 |
2002年 | 31篇 |
2001年 | 6篇 |
2000年 | 2篇 |
1999年 | 2篇 |
1998年 | 8篇 |
1997年 | 5篇 |
1996年 | 5篇 |
1995年 | 4篇 |
1994年 | 5篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1990年 | 1篇 |
1988年 | 4篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1982年 | 3篇 |
1980年 | 1篇 |
1975年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有1169条查询结果,搜索用时 18 毫秒
61.
Brambilla F Mellado C Alciati A Pisu MG Purdy RH Zanone S Perini G Serra M Serra M Biggio G 《Psychiatry research》2005,135(3):185-190
Plasma concentrations of neuroactive steroids in men with panic disorder (PD) were measured to evaluate their relations to psychopathology both before and during treatment. Participants comprised 13 men with PD and 10 normal controls. Patients were evaluated while drug-free as well as after 1 and 2 months of paroxetine therapy. Psychopathology was assessed by the State-Trait Anxiety Inventory (STAI), the Panic-Associated Symptom Scale, and the Fear Questionnaire total score. Plasma concentrations of steroids were measured by radioimmunoassay. The plasma concentrations of progesterone and dehydroepiandrosterone were greater in drug-free patients than in controls, whereas those of allopregnanolone and tetrahydrodeoxycorticosterone did not differ between the two groups. Paroxetine treatment for 2 months significantly increased the plasma concentration of allopregnanolone but did not affect those of the other steroids. At 2 months of therapy, allopregnanolone concentrations in patients were significantly greater than those in controls. The plasma concentrations of progesterone and tetrahydrodeoxycorticosterone correlated with the STAI state score in patients before treatment. Our data suggest that neuroactive steroids may play a role in PD in men. 相似文献
62.
Sciarra A Voria G Monti S Mazzone L Mariotti G Pozza M D'Eramo G Silverio FD 《The Prostate》2004,58(4):421-428
PURPOSE: To evaluate whether the pretreatment determination of serum chromogranin A (CgA) can provide information beyond that obtained with serum prostate specific antigen (PSA) and Gleason score at biopsy as a predictive factor of clinical understaging (T2-pT3) of prostate adenocarcinoma. MATERIALS: In this prospective study, we analyzed 83 consecutive patients with clinical T2N0M0 prostate adenocarcinoma submitted to radical prostatectomy (RRP). On the same day of RRP, before surgery, a blood sample for the determination of serum total PSA and CgA levels (RIA) was obtained. RESULTS: After RRP, 27 of the 83 cases (32.5%) showed extracapsular disease extension (pT3) at the final pathological examination and were considered clinically understaged. A significant association between serum CgA and pathological stage (r = 0.3830; P = 0.0004) was found. At the multivariate analysis, serum CgA and PSA, but not biopsy Gleason score, were found to be significant pretreatment independent predictors of pT3 at RRP (P = 0.00004 and P = 0.0018, respectively). The relative risk of clinical understaging significantly varied according to serum CgA levels. Using a CgA cut-off value of 60 ng/ml, PPV and NPV for clinical understaging were 0.5161 and 0.7885, respectively (P = 0.0072). CONCLUSIONS: Serum CgA could be incorporated into risk assessment models of newly diagnosed prostate cancer. 相似文献
63.
We used a short‐term bioassay—the Tradescantia stamen‐hair assay (TSH)—to evaluate the toxicity of ambient particles with an aerodynamic diameter less than 10 μm sampled in the metropolitan region of São Paulo, Brazil. Two exposure locations were selected: downtown São Paulo and Caucaia do Alto (mean PM10 levels of 64 and 14 μg/m3, respectively). The experiment was conducted July 11–August 15, 2002, and toxicity was assessed with the Tradescantia stamen‐hair assay (TSH) employing clone KU‐20 of Tradescantia. Four experimental groups were defined: inflorescences collected from plants cultivated in Caucaia, inflorescences collected from plants cultivated in São Paulo (to establish the baseline level of mutations in stamen hairs at both sites), inflorescences collected from plants cultivated in Caucaia and brought to São Paulo and maintained in chambers that received ambient air, and inflorescences collected from plants cultivated in Caucaia and brought to São Paulo and maintained in chambers that received air passed through a particle filter. The frequency of mutations observed in Caucaia was significantly lower than that in the remaining groups. Flower cuttings brought from Caucaia and receiving ambient air of São Paulo showed a rate of mutations similar to that of plants cultivated in São Paulo. Filtering particles from the air reduced the rate of mutation but not sufficiently to reach the level of that in Caucaia. The frequency of mutations observed in São Paulo was significantly associated with PM10 levels on the fifth day before the opening of the flowers (r = 0.47, p = 0.025). Our results indicate that urban particles play a significant role in the development of pollution‐dependent mutations. © 2004 Wiley Periodicals, Inc. Environ Toxicol 19: 578–584, 2004. 相似文献
64.
Hardoy MC Carta MG Catena M Hardoy MJ Cadeddu M Dell'Osso L Hugdahl K Carpiniello B 《Psychiatry research》2004,127(1-2):163-166
The Judgment of Line Orientation Test, a visuospatial processing task, was administered to normal subjects, to schizophrenic patients and to patients with delusional disorder. Significantly better performance was seen in the normal subjects than in the schizophrenic and delusional patients. Delusional patients, in turn, showed better performance than the schizophrenic patients. 相似文献
65.
Mauro?Giovanni?CartaEmail author Andrea?Loviselli Maria?Carolina?Hardoy Sergio?Massa Mariangela?Cadeddu Claudia?Sardu Bernardo?Carpiniello Liliana?Dell'Osso Stefano?Mariotti 《BMC psychiatry》2004,4(1):25
Background
To evaluate the association between mood and anxiety disorders and thyroid autoimmunity in a community sample. Methods: A community based sample of 222 subjects was examined. Psychiatric diagnoses were formulated using the International Composite Diagnostic Interview Simplified (CIDIS), according to DSM-IV criteria. All subjects underwent a complete thyroid evaluation including physical examination, thyroid echography and measure of serum free T4 (FT4), free T3 (FT3), thyroid-stimulating hormone (TSH) and anti-thyroid peroxidase autoantibodies (anti-TPO).Results
16.6% of the overall sample had an anti-TPO value above the normal cut-off. Subjects with at least one diagnosis of anxiety disorders (OR = 4.2, C.L. 95% 1.9–38.8) or mood disorders (OR = 2.9, Cl 95% 1.4–6.6, P < 0.011) were positive for serum anti-TPO more frequently than subjects without mood or anxiety disorders. A statistically significant association with anti-TPO+ was found in Anxiety Disorder Not Otherwise Specified (OR = 4.0, CL 95% 1.1–15.5), in Major Depressive Episode (OR = 2.7, CL 95% 1.1–6.7) and Depressive Disorder Not Otherwise Specified (OR = 4.4, S CL 95% 1–19.3).Conclusions
The study seems to suggest that individuals in the community with thyroid autoimmunity may be at high risk for mood and anxiety disorders. The psychiatric disorders and the autoimmune reaction seem to be rooted in a same (and not easy correctable) aberrancy in the immuno-endocrine system. Should our results be confirmed, the findings may be of great interest for future preventive and case finding projects.66.
Florio P Perrone S Luisi S Longini M Tanganelli D Petraglia F Buonocore G 《Pediatric research》2003,54(5):696-700
Activin-A is a growth factor involved in cell growth and differentiation, neuronal survival, early embryonic development and erythropoiesis. Hypoxemia is a specific trigger for increasing activin-A in fetal lamb circulation. We tested the hypothesis that fetal hypoxia induces activin-A secretion in preterm newborn infants. Fifty newborn infants with gestational ages ranging from 26 to 36 wk were enrolled in a prospective study performed at the Pediatrics, Obstetrics and Reproductive Medicine Department, University of Siena, Italy. Heparinized blood samples were obtained from the umbilical vein after cord clamping, immediately after delivery. Activin A, hypoxanthine (Hx), xanthine (Xa) plasma levels and absolute nucleated red blood cell (NRBC) count were measured. Activin-A levels (p < 0.0001) and NRBC (p < 0.0001) were significantly higher in hypoxic than in non hypoxic preterm newborns. Cord activin A levels were significantly related with Hx (taua=0.64, taub=0.64, p < 0.0001) and Xa (taua=0.56, taub=0.57, p < 0.0001) levels, NRBC ((taua=-0.45, taub=-0.46, p < 0.0001) count; pH (taua=-0.47, taub=-0.48, p < 0.0001) and base deficit (taua=-0.36, taub=0.-0.36, p = 0.0002). Preterm newborns with signs of perinatal hypoxia at birth have increased activin-A levels, suggesting that activin-A may reflect indirectly intrauterine hypoxia. 相似文献
67.
Using children's na?ve theory of biology as a framework, this study examined children's illness conceptions. Children (aged 4-11), presented with one of four exemplars (child, dog, duck or rosebush) suffering an imaginary illness, were asked whether various entities from six categories, biological and non-biological, could also be afflicted. The children's illness generalizations differentiated between all of the categories; they not only distinguished between living and non-living things, but also recognized biological subkinds. Furthermore, the children's generalizations were significantly greater to the category of exemplar, indicating that human prototypicality is not the sole basis for children's generalizations. It is concluded that children's understanding of illness is mediated by a na?ve biological theory that facilitates their systematic predictions of susceptibility to illness. 相似文献
68.
Quantitative determination of sufentanil in human plasma by liquid chromatography-tandem mass spectrometry 总被引:2,自引:0,他引:2
Palleschi L Lucentini L Ferretti E Anastasi F Amoroso M Draisci G 《Journal of pharmaceutical and biomedical analysis》2003,32(2):329-336
A sensitive and specific method for the quantification of sufentanil in human plasma by liquid chromatography coupled with tandem mass spectrometry has been developed. Fentanyl was used as the internal standard. Rapid sample preparation involved purification on a C(18) solid-phase extraction column. Chromatographic separation of the analytes was obtained using an RP-C(18) mu-HPLC column. LC-MS-MS detection was performed by atmospheric pressure ionisation (API) source equipped with an ionspray (IS) interface operating in the positive ion mode. For unambiguous substance confirmation, three analyte precursor-product ion combinations were monitored during multiple reaction monitoring (MRM) LC-MS-MS analysis. The method's performance characteristics were evaluated in blank and spiked control plasma samples. Overall accuracy (relative error, R.E., %), repeatability (relative standard deviations, R.S.D., %) and within-laboratory reproducibility (R.S.D., %) ranged from -9.28 to -2.71%, from 6.42 to 2.82% and from 13.52 to 6.06%, respectively, for sufentanil. The limit of quantification for sufentanil in human plasma samples was 0.3 ng ml(-1). Due to its high sensitivity and specificity, the method was successfully employed for sufentanil determination in maternal plasma samples collected immediately before epidural administration of a single sufentanil dose to women in labour, 20 min after drug administration, and at birth in arterial and venous umbilical cord plasma samples from the newborn babies. Research is in progress to adopt the method for performance of complete pharmacokinetic studies of sufentanil in human plasma. 相似文献
69.
Comparison of synthetic hydroxyapatite and porous polyethylene implants in eviscerated rabbit eyes 总被引:2,自引:0,他引:2
Schellini SA Marques ME Padovani CR Taga EM Rossa R 《Ophthalmic plastic and reconstructive surgery》2003,19(2):136-139
PURPOSE: Synthetic hydroxyapatite and porous polyethylene (Polipore) spheres were placed in rabbits' eviscerated cavities to evaluate tissue reaction and volume maintenance. METHODS: Fifty-six Norfolk albino rabbits underwent unilateral evisceration and implantation of synthetic hydroxyapatite (H group, 28 animals) or porous polyethylene spheres (P group, 28 animals). Postoperative reactions, animal behavior, and socket conditions were monitored. Light microscopy and morphometric evaluation with statistical analysis of the exenterated orbits were performed at 7, 15, 30, 60, 90, 120, and 180 days. Scanning electron microscopy was appraised 7, 60, and 180 days after surgery. RESULTS: Two animals from the H group and 1 from the P group had extrusion 7 days after surgery. Throughout the experimental period, the synthetic hydroxyapatite caused more inflammation than the porous polyethylene material. Ingrowth in the sphere occurred 7 to 15 days after the surgery in both groups, and the tissue reaction became denser at approximately 60 to 90 days, when bony metaplasia began in the H group. Volume maintenance was better in the P group and with a smaller pseudocapsule surrounding the implanted sphere than in the H group. CONCLUSIONS: Clinical findings demonstrated mild inflammation inside the sphere and in the pseudocapsule surrounding it and better cavity volume maintenance in the P group animals. The authors consider porous polyethylene a more suitable material than synthetic hydroxyapatite for use in anophthalmic cavity reconstruction. 相似文献
70.
The authors report their experience with a case of a voluminous malignant pleomorphic histiocytoma of the anterior abdominal wall occurring in an 81-year-old female patient. She presented with a one-year history of a non-painful, poorly mobile tumefaction which had grown in size over the 2 months prior to admission. A preoperative CT scan confirmed the presence of a 10-cm mass located in the anterior abdominal wall. The patient underwent resection of the tumour and was discharged on postoperative day 15. A 12-month follow-up has so far revealed no evidence of recurrence. The authors go on to examine the diagnostic and therapeutic treatments of these rare neoplasms with reference to the international scientific literature. They confirm the validity of radiotherapy but stress the elective role of surgical treatment. 相似文献