全文获取类型
收费全文 | 960篇 |
免费 | 53篇 |
国内免费 | 14篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 54篇 |
妇产科学 | 23篇 |
基础医学 | 93篇 |
口腔科学 | 73篇 |
临床医学 | 85篇 |
内科学 | 224篇 |
皮肤病学 | 10篇 |
神经病学 | 36篇 |
特种医学 | 117篇 |
外科学 | 117篇 |
综合类 | 25篇 |
预防医学 | 40篇 |
眼科学 | 39篇 |
药学 | 44篇 |
中国医学 | 1篇 |
肿瘤学 | 43篇 |
出版年
2023年 | 7篇 |
2022年 | 18篇 |
2021年 | 21篇 |
2020年 | 14篇 |
2019年 | 14篇 |
2018年 | 18篇 |
2017年 | 25篇 |
2016年 | 34篇 |
2015年 | 26篇 |
2014年 | 36篇 |
2013年 | 44篇 |
2012年 | 43篇 |
2011年 | 56篇 |
2010年 | 39篇 |
2009年 | 38篇 |
2008年 | 28篇 |
2007年 | 52篇 |
2006年 | 32篇 |
2005年 | 20篇 |
2004年 | 20篇 |
2003年 | 17篇 |
2002年 | 9篇 |
2001年 | 12篇 |
2000年 | 13篇 |
1999年 | 19篇 |
1998年 | 37篇 |
1997年 | 37篇 |
1996年 | 32篇 |
1995年 | 26篇 |
1994年 | 19篇 |
1993年 | 19篇 |
1992年 | 8篇 |
1991年 | 11篇 |
1990年 | 16篇 |
1989年 | 22篇 |
1988年 | 19篇 |
1987年 | 25篇 |
1986年 | 6篇 |
1985年 | 8篇 |
1984年 | 6篇 |
1983年 | 8篇 |
1980年 | 6篇 |
1977年 | 7篇 |
1976年 | 5篇 |
1975年 | 4篇 |
1973年 | 4篇 |
1972年 | 4篇 |
1971年 | 4篇 |
1970年 | 4篇 |
1967年 | 4篇 |
排序方式: 共有1027条查询结果,搜索用时 15 毫秒
51.
Ageing appearance in China: biophysical profile of facial skin and its relationship to perceived age
AE Mayes PG Murray DA Gunn CC Tomlin SD Catt YB Wen LP Zhou HQ Wang M Catt SP Granger 《Journal of the European Academy of Dermatology and Venereology》2010,24(3):341-348
Background Perceived age is important to women and is a primary driver for topical product use and facial cosmetic surgery. Changes in facial features and biophysical skin parameters with chronological age and their associations with perceived age have not been described in Asian populations. Objective To investigate the relationship between biophysical properties of the skin, visual features of skin ageing and perceived facial age in Chinese women. Methods Facial photographs were collected of 250 Chinese women, aged 25–70 years in Shanghai, China. The perceived facial age was determined and related to the chronological age for each participant and to a range of visual assessments of skin appearance and objective biophysical measurements of the skin. The profile of changes in these parameters with age was investigated together with the differences in those parameters for women judged to look younger than their chronological age and those judged to look older than their chronological age. Results Large discrepancies in perceived age (up to 29 years) were found in women of the same chronological age. Each objective skin measure and visual assessment parameter had a stronger correlation with perceived age than with chronological age. The strongest relationships to perceived age were for wrinkles and hyperpigmentation. Skin colour, hydration and trans‐epidermal water loss (TEWL) had weaker associations with perceived age. Women judged to look older than their chronological age had significantly higher scores than those judged to look younger for coarse wrinkles and hyperpigmentation across all age groups. The appearance differences between these groups were evident in composite facial images of the same average chronological age. Conclusions We have identified the skin attributes which differ with perceived age in Chinese women. Perceived age is a better measure of the biological age of facial skin than is chronological age in this population. 相似文献
52.
53.
Nandakumar Narayanaswamy Surulivel Rajan Mallayasamy Anand R Manoharan SD Rajendiran 《The International journal of pharmacy practice》2007,15(1):69-73
Objective India is a country with the availability of a large number of pharmaceutical preparations as branded generics. At the time of this study there was no established pharmacovigilance system at the national level except a co‐ordinating centre at the national capital. The study site was a tertiary care teaching hospital with a bed capacity of 500 and with an average of 200 outpatient visits and 50 inpatient admissions per day. The hospital did not have any system of monitoring and documenting adverse drug reactions. The objective of the study was to introduce an adverse drug reaction (ADR) monitoring programme at a tertiary care teaching hospital and assess ADR‐related issues in both inpatient and outpatient departments. Method All departments willing to report ADRs were included in the study, which was carried out for one year. Physicians and nurses filled in the notification forms when they encountered suspected ADR cases. These cases were then assessed by a panel of four judges. According to Naranjo's algorithm, the ADRs were assessed and classified based on World Health Organization (WHO) classification. Key findings A total of 288 suspected cases were reported and 264 ADRs were confirmed by the panel. According to Naranjo's probability scale, 83 cases were categorized as ‘probable’, 181 cases were classified as ‘possible’, and none were classified as ‘unlikely’ or ‘definite’. The most common classes of drugs involved were antibiotics (25%), psychotropics (20%), analgesic and cardiovascular agents (14% each). Generalised itch and rash, tremors, urticarial drug reaction, oral ulcer, gastritis and akathesia and extrapyramidal symptoms were found to be the most common ADRs observed; 2.1% of the patients in the studied departments had ADRs. Conclusion The ADR reporting system was initiated at the hospital and was well received by the physicians. Appreciable participation of physicians was noted during the study in reporting ADRs. The study also gave an insight into the awareness of physicians about ADR‐related issues. The number of ADRs reported was reasonably comparable with the findings of other authors from India. 相似文献
54.
Howells RE Tucker H Millinship J Shroff JF Dhar KK Jones PW Redman CW 《BJOG : an international journal of obstetrics and gynaecology》2000,107(1):28-32
Objective To test the hypothesis that prilocaine with felypressin causes fewer side effects than lignocaine with adrenaline when performing large loop excision of the transformation zone of the cervix.
Design Randomised trial.
Setting Colposcopy clinic in a large district general hospital.
Participants Two hundred consecutive women undergoing large loop excision of the transformation zone of the cervix.
Methods Two different local anaesthetic combinations (prilocaine with felypressin and lignocaine with adrenaline) were compared in women undergoing large loop excision of the transformation zone. Prospective collection of clinical and treatment data was undertaken with scoring using an ordinal scale of pain experienced by the women during the procedure. Peri-operative blood loss and any side effects were also recorded.
Main outcome measures Side effects associated with the local anaesthetic agents.
Results Lignocaine with adrenaline resulted in less blood loss ( P = 0.006 ) but was more likely to cause side effects, such as feeling faint ( P = 0.017 ) and shaking ( P < 0.001 ).
Conclusion Prilocaine with felypressin causes fewer side effects than lignocaine with adrenaline and is therefore the preferred local anaesthetic combination for large loop excision of the transformation zone. 相似文献
Design Randomised trial.
Setting Colposcopy clinic in a large district general hospital.
Participants Two hundred consecutive women undergoing large loop excision of the transformation zone of the cervix.
Methods Two different local anaesthetic combinations (prilocaine with felypressin and lignocaine with adrenaline) were compared in women undergoing large loop excision of the transformation zone. Prospective collection of clinical and treatment data was undertaken with scoring using an ordinal scale of pain experienced by the women during the procedure. Peri-operative blood loss and any side effects were also recorded.
Main outcome measures Side effects associated with the local anaesthetic agents.
Results Lignocaine with adrenaline resulted in less blood loss ( P = 0.006 ) but was more likely to cause side effects, such as feeling faint ( P = 0.017 ) and shaking ( P < 0.001 ).
Conclusion Prilocaine with felypressin causes fewer side effects than lignocaine with adrenaline and is therefore the preferred local anaesthetic combination for large loop excision of the transformation zone. 相似文献
55.
Shroff R Trompeter R Cubitt D Thaker U Rees L 《Pediatric nephrology (Berlin, Germany)》2002,17(9):770-775
Prospective Epstein-Barr virus (EBV) surveillance post transplant was undertaken by qualitative polymerase chain reaction testing for EBV DNA in plasma so as to detect EBV viremia as early as possible and thereby attempt to pre-empt post-transplant lymphoproliferative disease by reduction of immunosuppression. Forty-three children (46 transplants) were followed for a median (range) of 15.5 (3-25) months. Thirty-one children (67%) were EBV seropositive pre transplant. Twenty children (44%) developed EBV viremia; of these 9 (60%) were seronegative and 11 (36%) seropositive recipients. Primary infection developed later (median difference 14.2 weeks, P=0.009), was more likely to be symptomatic (odds ratio 2.91, 95% confidence interval 0.95-4.88) and associated with a rise in serum creatinine (odds ratio 6.13, 95% confidence interval 4.13-8.13) than reactivation disease. There was a higher incidence of EBV disease in children receiving quadruple therapy and tacrolimus (odds ratio 13.2, 95% confidence interval 11.5-14.9) compared with those given cyclosporin-based immunosuppression. Immunosuppression was reduced when EBV infection was detected. All children became asymptomatic and renal function returned to normal by a median (range) of 17 (6-52) days, although mild relapses occurred in 3 children. Regular EBV surveillance allowed prompt reduction of immunosuppression and was associated with a good outcome in this group of children. 相似文献
56.
Perkins SN; Hursting SD; Haines DC; James SJ; Miller BJ; Phang JM 《Carcinogenesis》1997,18(5):989-994
Transgenic mice with both alleles of the p53 tumor suppressor gene product
'knocked out' by gene targeting are susceptible to early development of
tumors, chiefly lymphomas and sarcomas. Compared with the control group,
administration of dehydroepiandrosterone (DHEA) at 0.3% of the diet to male
p53-deficient mice extended their lifespan by delaying death due to
neoplasms (from 105 to 166 days on study, P = 0.002), primarily by
suppressing lymphoblastic lymphoma (from 45 to 6% of neoplastic deaths, P =
0.010). Treatment with a synthetic DHEA analog,
16alpha-fluoro-5-androsten-17-one (compound 8354), at 0.15% of the diet
also increased lifespan, to 140 days for mice that developed tumors (P =
0.037). The effects of these steroids on lifespan and tumor development did
not appear to be strongly related to inhibition of food consumption and
weight gain, in that a group pair-fed with control diet to the reduced food
consumption of the DHEA-treated group developed and died of the same types
of neoplasms at the same rate as the controls fed ad libitum. The
chemopreventive effect of these steroids has been proposed to be due to
suppression of DNA synthesis by inhibition of glucose 6-phosphate
dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway.
Although DHEA and its analog are strong non- competitive inhibitors of this
enzyme in vitro, treatment with DHEA did not deplete cellular nucleotide
pools in the liver, as would have been predicted. The chemopreventive
effect of DHEA in this model may be due to steroid-induced thymic atrophy
and suppression of T cell lymphoma, permitting these mice to survive long
enough to develop tumors with longer latency.
相似文献
57.
58.
A high-pressure liquid chromatographic method is described for analyzing triflubazam [1-methyl-5-phenyl-7-trifluoromethyl-1H-1,5-benzodiazepine-2,4(3H,5H)-dione] and its primary metabolites in blood and urine. Adsorption chromatography, using pellicular silica gel as the stationary phase and dioxane-isooctane as the mobile phase, permitted rapid sample analysis. After extraction of blood and urine samples with toluene, quantitation is achieved using liquid chromatography with an internal standard. The method is sensitive above 50 ng/ml of triflubazam and its known metabolites. Recoveries for all compounds from blood or urine averaged above 95 percent. The specificity of the method was established by collecting samples separated by liquid chromatography and characterizing them by mass spectrometry. Human and animal data are presented to illustrate the utility of the method. 相似文献
59.
60.