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51.
BACKGROUND: Mobile mammography can be useful in reaching medically underserved women. However, it is not known whether self-referral for mobile mammography is the best approach for reaching the most vulnerable populations. OBJECTIVES: 1) To describe the community outreach patterns of a county-sponsored mobile mammography unit, 2) To characterize the follow-up patterns for women with abnormal screening mammograms, and 3) to identify reasons why women screened on mobile units seek follow-up care outside of the safety-net system. METHODS: We prospectively followed women aged > or = 40 years who received mobile mammograms using electronic records and medical chart review, and surveyed women who had no evidence of diagnostic follow-up. We also reviewed administrative records to determine outreach patterns of the mobile mammography units. RESULTS: Seventy-five percent of mobile visits were with community-based organizations or community health centers. At least one quarter of women chose to follow-up outside of the safety-net for evaluation of abnormal screening mammograms. Of these, nearly 40% reported having insurance or a private physician as the primary reason for having diagnostic evaluation outside of the public hospital system. CONCLUSIONS: Despite serving primarily community-based facilities, self-referral for mobile mammography may not optimally target medically underserved women most in need of breast cancer screening. 相似文献
52.
SP Walker M Permezel SF Berkovic 《BJOG : an international journal of obstetrics and gynaecology》2009,116(6):758-767
While most women with epilepsy can expect a normal pregnancy outcome, epilepsy remains a significant contributor to both maternal and perinatal morbidity. Pre-pregnancy planning must address reliable contraception and optimisation of antiepileptic drug (AED) regimens to minimise teratogenic risk while maintaining seizure control. The most recent data from the AED registries regarding malformations is presented in this review, as is the limited data on the newer AEDs and studies linking neurocognitive outcomes to AED exposure. During pregnancy, important considerations include; therapeutic drug monitoring, surveillance for obstetric complications and vigilance for seizures during the intrapartum and postpartum period. 相似文献
53.
MC Chau SF Leung KM Kam KY Cheung WH Kwan KH Yu KW Chiu TC Chan 《Journal of Medical Imaging and Radiation Oncology》2007,51(5):480-484
To assess the dosimetric effect of using interpolated contours in planning intensity‐modulated radiation therapy (IMRT) for advanced T‐stage nasopharyngeal carcinoma. The present study focused on T3–T4 tumours where the proximity of targets to neurological organs poses a stringent test on the feasibility of such an approach. Contours of targets and organs were delineated on CT images of 2.5‐mm interval and a reference IMRT plan was generated. An investigative (INV) IMRT plan was then generated with the same planning protocol, but based on interpolated contours that replaced deleted contours on alternate slices. The reference and INV plans were compared. Regarding target coverage, all targets in the INV plans met the acceptance criteria except for the PTV in one case. Regarding organs, the mean dose to 1% volume of the brainstem and spinal cord in the INV plans were kept below their dose limits. No significant differences in the mean doses to others organs were found. Satisfactory target coverage and protection of critical organs to a degree similar to full‐scale contouring could be achieved with use of interpolated contours. The saving in manpower time for contouring is expected to significantly improve the throughput of the IMRT planning process. 相似文献
54.
SF Slaney AO Wilkie MC Hirst R Charlton M McKinley J Pointon Z Christodoulou SM Huson KE Davies 《Archives of disease in childhood》1995,72(1):33-37
Fragile X syndrome is the most common inherited cause of mental retardation. Early diagnosis is important not only for appropriate management of individuals but also to identify carriers who are unaware of their high risk of having an affected child. The disorder is associated with a cytogenetically visible fragile site (FRAXA) at Xq27.3, caused by amplification of a (CGG)n repeat sequence within the gene at this locus designated FMR1. Clinical and molecular studies have been undertaken to screen for fragile X syndrome in 154 children with moderate and severe learning difficulties of previously unknown origin. Southern blot analysis of peripheral blood showed the characteristic abnormally large (CGG)n repeat sequence associated with fragile X syndrome in four of the 154 children. The findings were confirmed by cytogenetic observation of the fragile site and by further molecular studies. The families of the affected children were offered genetic counselling and DNA tests to determine their carrier status. These findings show that there are still unrecognised cases of fragile X syndrome. Given the difficulty of making a clinical diagnosis and the implications for families when the diagnosis is missed, screening in high risk populations may be justified. The issues involved in screening all children in special schools for fragile X syndrome are discussed. 相似文献
55.
Meek B Klaren VN van Haeringen NJ Kijlstra A Peek R 《Investigative ophthalmology & visual science》2000,41(9):2584-2590
PURPOSE: To investigate whether mucosal immune responses directed against the ubiquitous parasite Toxoplasma gondii can be detected in tears of healthy humans. METHODS: Nonstimulated tears and blood were obtained from 62 healthy humans (mean age, 35 +/- 10 [SD] years). Serum anti-T. gondii immunoglobulin titers were determined by Sabin-Feldman (SF) dye test. Western blot analysis was used to compare the anti-T. gondii repertoire in tears and serum, and antibody avidity was determined by urea elution. Diluted tear and serum samples were incubated with the intact parasite to determine whether the antibodies found in tears and serum are capable of binding to surface exposed antigens of T. gondii. RESULTS: Eighty-one percent of the individuals tested had an anti-T. gondii IgA response in their tears, whereas only 23% had evidence of systemic immunity against the parasite. There was no apparent relation between chronic infection and presence of anti-T. gondii IgA in tears. Characteristically, the antigens recognized by the IgA antibodies in tears were often limited to at least one of four antigens with molecular weights of 74, 70, 49, and 34 kDa. The avidity of the anti-T. gondii IgA antibodies in tears was similar to the avidity of serum IgG antibodies. IgA antibodies directed against the 49- and 74-kDa antigens recognized epitopes exposed on the surface of the parasite. CONCLUSIONS: A major finding of this study is that tears of many individuals, chronically infected or not, contain IgA antibodies against T. gondii. It is not known whether these frequently observed antibody responses are the result of common mucosal immune responses against T. gondii or represent the natural antibody repertoire. 相似文献
56.
John C. Peek Vernon J. Choy Wayne B. Watkins Frederick M. Graham 《Journal of assisted reproduction and genetics》1987,4(2):103-106
Oxytocinlike immunoreactivity, estradiol, and progesterone were measured in follicular fluid collected during oocyte collection in an in vitro fertilization program in which clomiphene citrate was used to stimulate follicular development. Follicles which yielded morphologically normal embryos after fertilization of the oocyte had oxytocin concentrations ranging from <10 to 600 ng/liter. Oxytocin concentrations did not differ between follicles from 12 pregnancy cycles (median, 169; N=21 and follicles from 12 nonpregnancy cycles (median, 110; N= 18). Oxytocin concentrations were correlated negatively with progesterone concentrations (Spearman's rank correlation coefficient r=–0.50; P=0.001). In cycles with some follicles having progesterone concentrations <10 and some >10 mol/liter, oxytocin concentrations were higher in the less progestogenic follicles in 15 of 16 cases. 相似文献
57.
The suitability of an air-exposed culture model consisting of a collagen matrix was investigated for constructing an advancing front (AF) of human middle ear epithelium (MEE) and meatal epidermis (ME). Three different culture settings were used: (i ) MEE; (ii) ME; and (iii) AF (MEE + ME). Small tissue biopsies were placed on a fibroblast-populated collagen matrix and grown at the air-liquid interface. After 3 weeks of culture, the MEE and ME outgrowth was differentiated. Light, scanning electron and transmission electron microscopy showed no visible differences compared to native MEE and ME. Cytokeratin 8 and cytokeratin 10 expressions were comparable to the expression seen in the native MEE and ME tissues. Proliferation, which was demonstrated by the expression of Ki-67, was present in the basal layers of cultured MEE and ME. A double layer of cells in which the ME covered the MEE formed the AF. In the AF, the MEE and ME showed the same morphological and immunohistochemical characteristics as in their native tissues. The results of the study show that this in vitro system is a well-defined model system offering the possibility to study the effects of external stimuli on the different epithelia of the AF involved in the pathogenesis of cholesteatoma. 相似文献
58.
Interleukin-1beta and interleukin-1 receptor antagonist gene polymorphisms and gastric cancer: a meta-analysis. 总被引:6,自引:0,他引:6
M Constanza Camargo Robertino Mera Pelayo Correa Richard M Peek Elizabeth T H Fontham Karen J Goodman M Blanca Piazuelo Liviu Sicinschi Jovanny Zabaleta Barbara G Schneider 《Cancer epidemiology, biomarkers & prevention》2006,15(9):1674-1687
BACKGROUND: Polymorphisms of interleukin-1B (IL1B) and its receptor antagonist (IL1RN) genes have been inconsistently associated with gastric cancer risk. We examined these associations by performing meta-analyses. MATERIALS AND METHODS: Twenty-five studies testing the association between IL1B and/or IL1RN gene polymorphisms and gastric cancer were examined: 14 studies of IL1B-511, 14 studies of IL1B-31, 8 studies of IL1B+3954, and 23 studies of IL1RN. Overall and ethnicity-specific summary odds ratios and corresponding 95% confidence intervals for gastric cancer associated with these polymorphisms were estimated using fixed- and random-effects models. Heterogeneity and publication bias were evaluated. RESULTS: IL1B-511T and IL1RN*2 were associated with gastric cancer risk in Caucasians, but not in Asians. For IL1B-511T, the association in Caucasians was stronger when intestinal-subtype and noncardia gastric cancer cases were examined. A nonsignificant trend was observed between IL1B-31C and gastric cancer in Caucasians. No significant association of IL1B+3954T and gastric cancer risk was detected. Studies with better methodologic characteristics reported stronger effects. There was no evidence of publication bias. CONCLUSION: IL1B-511T is associated with gastric cancer susceptibility in Caucasians. The meta-analyses suggest that the conflicting results among studies may be explained by variation in allele frequencies among the ethnic groups and variation in tumor types, as well as by the methodologic quality of the studies. 相似文献
59.
Objective : Inhaled nitric oxide (iNO) has been shown to cause selective pulmonary vasodilatation and improve ventilation-perfusion matching and may be an important therapeutic option for the treatment of persistent pulmonary hypertension of the newborn (PPHN). We report our experience on the use of iNO in neonates with severe PPHN.
Methodology : Inhaled NO was administered to 10 infants with PPHN and persistent hypoxaemia (meconium aspiration syndrome, n = 9; pneumonia, n = 1) after failure of conventional therapy to improve oxygenation. With the exception of one infant, iNO was commenced at 10 ppm.
Results : After 30 min exposure to iNO, the arterial oxygen tension (PaO2 ) rose from a median of 49 mmHg (6.5 kPa) [range 12-82 mmHg (1.6-10.9 kPa)] to 75 mmHg (10 kPa) [range 17-450 mmHg (2.3-60 kPa)] ( P = 0.005), while the median oxygenation index fell (pre-iNO of 37 vs post-iNO 20) ( P = 0.005) and median systemic arterial pressure rose (pre-iNO 46.5 mmHg (6.2 kPa) [range 32-63 mmHg (4.3 to 8.4 kPa vs post-iNO 54.5 mmHg (7.3 kPa) [range 36-74 kPa]) P = 0.005). All infants subsequently continued to receive iNO with the duration of exposure to iNO ranging from 12 to 168 h (median duration 100 h). Three infants died despite showing an initial beneficial response to iNO. The mean duration of intubation for survivors was 11.9 ± 2.6 days. Methaemoglobinaemia and toxic levels of nitrogen dioxide were not seen during iNO administration. Of the seven survivors, 12 month follow up in two infants and 4 month follow up in four infants showed age-appropriate neurodevelopmental skills, with one infant having very mild hearing loss.
Conclusions : Inhaled NO reduces the oxygenation index by improving the PaO2 and decreasing ventilation pressures, and appears to be clinically useful in severely hypoxaemic infants with PPHN refractory to conventional treatment. 相似文献
Methodology : Inhaled NO was administered to 10 infants with PPHN and persistent hypoxaemia (meconium aspiration syndrome, n = 9; pneumonia, n = 1) after failure of conventional therapy to improve oxygenation. With the exception of one infant, iNO was commenced at 10 ppm.
Results : After 30 min exposure to iNO, the arterial oxygen tension (PaO
Conclusions : Inhaled NO reduces the oxygenation index by improving the PaO
60.
ABSTRACT Inhaled nitric oxide is currently being investigated as a selective pulmonary vasodilator for neonates with persistent pulmonary hypertension. The use of continuous inhaled nitric oxide during emergency transportation of three critically ill neonates with meconium aspiration and pulmonary hypertension is described. The successful application of this technique may allow safer transportation of neonates who require high level intensive care including ongoing nitric oxide, high frequency ventilation and/or extracorporeal life support. Regionally based nitric oxide-equipped retrieval teams may relieve the pressure on smaller neonatal intensive care units to provide inhaled nitric oxide therapy and allow centralization of nitric oxide resources, thus facilitating development of expertise and the completion of meaningful research programs with substantial recruitment. 相似文献