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排序方式: 共有214条查询结果,搜索用时 535 毫秒
1.
目的探讨三康胶囊对高原人体运动后一氧化氮(NO)及其合酶(NOS)、乳酸(BLA)、血氨(Ammo)的影响.方法选择进驻海拔3 700 m高原1年的10名健康青年,口服三康胶囊15 d,在服药前后分别采用功量自行车进行渐增负荷运动,测定其血清 NO、NOS、BLA及Ammo含量.结果服药后较服药前运动后NO水平[(101.02±6.49) Vs (77.10±8.11)]和NOS活性[(71.40±7.23) Vs (56.29±6.28)]均增高, BLA[(7.58±0.79)Vs (6.13±0.74)]和Ammo[(80.11±9.44)Vs (69.38±8.86)]降低,有非常显著性差异(P<0.01).结论 三康胶囊能增强高原移居者运动后NOS活性,加速乳酸清除,减缓运动疲劳的发生. 相似文献
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The aim of the present study was to examine whether ischaemic episodes of less than 5 min could induce preconditioning or stunning in the isolated rat heart. Hearts were subjected to total global ischaemia of 1, 2 and 4 min followed by 10 min of reperfusion before an 18-min main ischaemic period and 30 min of reperfusion. The effects on physiology, purine metabolism and anaerobic glycolysis were compared with a control group subjected to the main ischaemia only. The brief ischaemic episodes did not produce stunning based on the recovery of left ventricular developed pressure (LVDP) and heart rate (HR) product during the first reperfusion. Preconditioning of 11–14% increased recovery of LVDP x HR during the second reperfusion was observed in the 1- and 4-min group. In the 2-min group a low repayment of flow debt during the first reperfusion was associated with a slightly reduced recovery of LVDP x HR compared to the other preconditioned groups during the second reperfusion. Only in the 4-min group was preconditioning associated with fewer breakdown products of the purine nucleotide pool (adenosine) and anaerobic glycolysis (lactate) in both tissue and effluate after the main ischaemia. Preconditioning (reflected in recovery of function) could be produced with ischaemic episodes of less than 5 min that did not produce stunning. Thus, stunning is probably not the primary cause of preconditioning. 相似文献
4.
Aberrant crypt focus promotion and glucose intolerance: correlation in the rat across diets differing in fat, n-3 fatty acids and energy 总被引:1,自引:0,他引:1
Koohestani N; Chia MC; Pham NA; Tran TT; Minkin S; Wolever TM; Bruce WR 《Carcinogenesis》1998,19(9):1679-1684
McKeown-Eyssen (Cancer Epidemiol. Biomarkers Prevent., 3, 687-695, 1994)
and Giovannucci (Cancer Causes Control, 6, 164-179, 1995), noting the
striking similarity in lifestyle risk factors for colorectal cancer and
insulin resistance, proposed that the hyperinsulinemia, glycemia and
hypertriglyceridemia associated with insulin resistance promotes colon
cancer. To compare the effect of diet on colon cancer promotion and insulin
resistance in the F344 rat, we assessed the effect of fat, n-3 fatty acids
and energy in pairwise comparisons on average size of aberrant crypt foci
(ACF) and on glucose intolerance in the same animals in a single
experiment. Diets high in fat and energy increased and diets with increased
n-3 fatty acids and calorie restriction decreased both ACF growth and
glucose intolerance compared with control diets. The measures of promotion
of colon cancer and insulin resistance were strongly correlated (n = 98, r
= 0.67, P < 0.001). In addition, both were highly correlated with daily
energy intake (r = 0.62 and 0.66) and were also correlated with basal
(post-prandial) insulin, glucose and triglycerides (r = 0.31-0.53, P <
0.01). We concluded that ACF growth and glucose intolerance are correlated
for a wide range of diets and that increased circulating energy (glucose
and triglycerides) may lead to both colon cancer promotion and insulin
resistance.
相似文献
5.
Nicole Schupf Sandra Barral Thomas Perls Anne Newman Kaare Christensen Bharat Thyagarajan Michael Province Winifred K. Rossi Richard Mayeux 《Neurobiology of aging》2013
Exceptional longevity is associated with substantial heritability. The ?4 allele in apolipoprotein E and the linked G allele in rs2075650 of TOMM40 have been associated with increased mortality and the ?2 allele with decreased mortality, although inconsistently. Offspring from long-lived families and spouse controls were recruited at 3 sites in the United States and Denmark. We used generalized estimating equations to compare the likelihood of carrying risk alleles in offspring (n = 2307) and spouse controls (n = 764), adjusting for age, sex, level of education, and family membership. The likelihood of carrying an APOE ?4 allele or a G allele in rs2075650 was lower (odds ratio [OR], 0.75; p = 0.005 and OR, 0.70; p = 0.002) and the likelihood of carrying an APOE ?2 allele was higher (OR, 1.5; p = 0.007) among family members in the offspring generation than among their spouse controls. Our findings support the hypothesis that both reduction in the frequency of the ?4 allele and increase in the frequency of the ?2 allele contribute to longevity. 相似文献
6.
Hyperbaric oxygen therapy improves angiogenesis and bone formation in critical sized diaphyseal defects 下载免费PDF全文
JP Grassmann J Schneppendahl AR Hakimi M Herten M Betsch TT Lögters S Thelen M Sager M Wild J Windolf P Jungbluth M Hakimi 《Journal of orthopaedic research》2015,33(4):513-520
Besides the use of autologous bone grafting several osteoconductive and osteoinductive methods have been reported to improve bone healing. However, persistent non‐union occurs in a considerable number of cases and compromised angiogenesis is suspected to impede bone regeneration. Hyperbaric oxygen therapy (HBO) improves angiogenesis. This study evaluates the effects of HBO on bone defects treated with autologous bone grafting in a bone defect model in rabbits. Twenty‐four New‐Zealand White Rabbits were subjected to a unilateral critical sized diaphyseal radius bone defect and treated with autologous cancellous bone transplantation. The study groups were exposed to an additional HBO treatment regimen. Bone regeneration was evaluated radiologically and histologically at 3 and 6 weeks, angiogenesis was assessed by immunohistochemistry at three and six weeks. The additional administration of HBO resulted in a significantly increased new bone formation and angiogenesis compared to the sole treatment with autologous bone grafting. These results were apparent after three and six weeks of treatment. The addition of HBO therapy to autologous bone grafts leads to significantly improved bone regeneration. The increase in angiogenesis observed could play a crucial role for the results observed. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 33:513–520, 2015. 相似文献
7.
Andersen SL Terry DF Wilcox MA Babineau T Malek K Perls TT 《Mechanisms of ageing and development》2005,126(2):263-267
Our previous work revealed that 88% of centenarians delay or escape the age-related lethal diseases cardiac disease, stroke and diabetes. In the cases of those having a history of cancer we have observed anecdotes of centenarians presenting with large primary tumors that would have otherwise been expected to have metastasized and to have been lethal. However, these tumors were removed without consequence. To better understand the relationship between cancer and exceptional longevity, we quantified age of cancer diagnoses, life-time clinically evident cancer prevalence, tobacco use and family histories through medical record review and interviews. One thousand one hundred and forty-three subjects were studied revealing 20% (N=152) of female and 22% (N=80) of male centenarians with a history of non-skin cancer. The most common cancers were prostate (11.7% of males), breast (8.2% of females), and colon (5.7%). The average age of diagnosis was 80.5 years compared to 63.2 years in the general population according to National Cancer Institute SEER data. Similar delays were noted when age of onset was examined according to specific type of cancer. In conclusion, the age of diagnosis of cancer is relatively delayed in those who live to 100 years. Some cancers are very rare among these individuals suggesting that there are certain cancers that may be incompatible with survival to extreme old age. 相似文献
8.
There is a substantial distinction to be made between the genetics of aging and the genetics of exceptional longevity. Twin studies suggest that the average set of genetic variations facilitates the average human's ability to live well into their octogenarian years. Other studies indicate that taking full advantage of this average set results in spending the majority of those years in good health. However, many people counteract such genetic endowment with poor health habits, resulting in a substantially lower average life expectancy and relatively more time spent in poor health. To live beyond the octogenarian years, life-span experiments in lower organisms and mammals and population and molecular genetic studies of centenarian sibships suggest that genetic factors play an important role in exceptional longevity. These factors are likely to influence basic mechanisms of aging, which in turn broadly influence susceptibility to age-related illnesses. Lacking genetic variations that predispose to disease, and having variations that confer disease resistance (longevity enabling genes), are probably both important to such a remarkable survival advantage. Recent studies indicate the likelihood that such factors will be elucidated in the near future. 相似文献
9.
Silver MH Jilinskaia E Perls TT 《The journals of gerontology. Series B, Psychological sciences and social sciences》2001,56(3):P134-P140
The New England Centenarian Study is a population-based study of all centenarians in 8 towns near Boston, MA. Age was confirmed for 43 centenarians all alive on a designated date. To determine prevalence of dementia in centenarians, the authors analyzed neuropsychological, medical, and functional status data for 34 (79%) of the centenarians. Definition of dementia was based on the Consortium to Establish a Registry for Alzheimer's Disease criteria, and a Clinical Dementia Rating (CDR) score was formulated for each participant. Seven (21%) had no dementia (CDR score 0), and an additional 4 (12%) were assigned a CDR score of 0.5, uncertain or deferred diagnosis. The remaining 22 (64%) had at least some degree of dementia. The authors calculated Barthel Index scores to determine ability to perform activities of daily living. There was a statistically significant correlation between CDR scores and Barthel Index scores (r = -0.73). Correlation was strongest for those with no or severe dementia, with the greatest range of function measured among those with moderate dementia. 相似文献
10.
Hoang L Phuong Tran TT Nga Phan T Giao Le Q Hung Tran Q Binh Nguyen V Nam Nico Nagelkerke Peter J de Vries 《BMC health services research》2010,10(1):275