全文获取类型
收费全文 | 557篇 |
免费 | 31篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 38篇 |
妇产科学 | 1篇 |
基础医学 | 69篇 |
口腔科学 | 17篇 |
临床医学 | 67篇 |
内科学 | 110篇 |
皮肤病学 | 20篇 |
神经病学 | 26篇 |
特种医学 | 121篇 |
外科学 | 36篇 |
综合类 | 12篇 |
预防医学 | 30篇 |
眼科学 | 1篇 |
药学 | 25篇 |
肿瘤学 | 33篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 14篇 |
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 3篇 |
2017年 | 7篇 |
2016年 | 8篇 |
2015年 | 12篇 |
2014年 | 14篇 |
2013年 | 20篇 |
2012年 | 9篇 |
2011年 | 13篇 |
2010年 | 31篇 |
2009年 | 36篇 |
2008年 | 11篇 |
2007年 | 26篇 |
2006年 | 18篇 |
2005年 | 14篇 |
2004年 | 13篇 |
2003年 | 3篇 |
2002年 | 7篇 |
2001年 | 11篇 |
2000年 | 4篇 |
1999年 | 8篇 |
1998年 | 35篇 |
1997年 | 37篇 |
1996年 | 30篇 |
1995年 | 29篇 |
1994年 | 11篇 |
1993年 | 19篇 |
1992年 | 3篇 |
1991年 | 6篇 |
1990年 | 11篇 |
1989年 | 13篇 |
1988年 | 19篇 |
1987年 | 15篇 |
1986年 | 9篇 |
1985年 | 12篇 |
1984年 | 6篇 |
1983年 | 7篇 |
1982年 | 12篇 |
1981年 | 5篇 |
1980年 | 9篇 |
1978年 | 7篇 |
1977年 | 6篇 |
1976年 | 7篇 |
1975年 | 5篇 |
1957年 | 1篇 |
1953年 | 1篇 |
排序方式: 共有609条查询结果,搜索用时 15 毫秒
31.
A Ross GM Raab J Mok S Gilkison B Hamilton FD Johnstone 《Archives of disease in childhood》1995,73(6):490-495
OBJECTIVE: To determine the separate effects of maternal HIV infection and drug use during pregnancy on growth of uninfected children in their first 3 years. DESIGN: Retrospective analysis of measurements from health visitor records made during routine child health surveillance at 6 weeks, 10 months, and 3 years of age. Multilevel analysis allowed for between-infant variation in fitted growth lines, and adjustment for other factors. Growth was described in terms of an intercept (z score at term) and growth slopes (change in z score per year) up to, and from, 4 months. SUBJECTS: 290 case babies delivered in Edinburgh hospitals to women who reported injection drug use by either themselves or their HIV infected partner, and 186 community controls. A total of 131 (45%) of the case babies were born to women who used drugs, predominantly opiates, during pregnancy and 93 (32%) to HIV infected women. The eight infected children were excluded from analysis. MAIN OUTCOME MEASURES: Age and sex standardised z scores for height, weight, and body mass index. RESULTS: 459 (96%) of the 476 records for cases and controls were traced, yielding 1432 weight and 939 height measurements. Maternal HIV infection was not found to affect growth; at 3 years the estimated effect on weight z score was 0.16 with 95% confidence interval (-0.25 to 0.57) and for height 0.18 (-0.19 to 0.55). Drug use during pregnancy was associated with lighter babies at 40 weeks followed by depressed growth in the first four months, these infants remaining just slightly smaller at 3 years with an estimated effect on z scores of -0.5 for weight with 95% confidence interval (-0.89 to -0.11) and -0.37 (-0.72 to -0.02) for height. CONCLUSIONS: Maternal HIV infection does not adversely affect growth in uninfected infants, and the effect of drug use during pregnancy is limited to small decrease in size at 3 years. 相似文献
32.
GM Thambugala A Mohamed GFA O Neill MJ Fulham 《Journal of Medical Imaging and Radiation Oncology》2006,50(6):604-606
We present the FDG PET‐CT findings in a patient with persistent pain 7 weeks after a nephrectomy and lymph node dissection for a sarcomatoid renal cell carcinoma. Although conventional imaging was unable to detect evidence of metastatic spread outside the para‐aortic nodes, a PET‐CT scan showed unexpected extensive dissemination. Currently, there are no reports in the literature of the PET‐CT findings in sarcomatoid renal cell carcinomas. 相似文献
33.
34.
A striking difference between two structurally related anti-estrogen
medicines is that tamoxifen is strongly hepatocarcinogenic in the rat,
whereas toremifene lacks such activity. To study the basis for this
difference, the initiating potential of tamoxifen and toremifene were
studied by measurement of rapid induction of hepatocellular altered foci
(HAF) that express placental-type glutathione S-transferase in the livers
of female Sprague-Dawley (S-D) rats and female Fischer 344 (F344) rats.
Both agents were administered by gavage at equimolar doses up to a dose
that produced marked weight gain suppression. In rats given the high dose
of 40 mg/kg per day tamoxifen continuously for 36 weeks, 75% of S-D rats
developed liver neoplasms, in contrast to only 10% of F344 rats. In the S-D
strain, tamoxifen produced a tendency to increased HAF at 2 weeks at the
dose of 40 mg/kg per day and by 12 weeks, a dose-related increase was
evident. In contrast, toremifene induced no HAF even at the equimolar high
dose of 42.4 mg/kg per day for 12 weeks. The induction of HAF by tamoxifen
was less in the F344 rats. Neither agent elicited increases in
hepatocellular proliferation in S-D or F344 rats. When phenobarbital was
administered for 24 weeks as a promoting agent after the anti-estrogens,
S-D rats given tamoxifen at 20 mg/kg per day for 12 weeks, developed liver
neoplasms, but not F344 rats or rats of either strain given even a higher
dose (42.4 mg/kg) of toremifene. Thus, tamoxifen has initiating activity in
these rat strains whereas toremifene does not.
相似文献
35.
36.
De Angelis MV Capasso M Anghiari C Cavallaro T Di Muzio A Fabrizi GM Uncini A . 《Journal of the peripheral nervous system : JPNS》2004,9(2):121-121
Painful sensory neuropathies consist of a wide range of neuropathies that can involve large as well as small nerve fibres. Even if most cases remain of unknown cause, some of them may be associated with an underlying disorder such as diabetes, HIV, infections, amyloidosis, and Sjogren's syndrome. Since in some cases an autoimmune mechanism has been postulated, we investigated a panel of circulating autoantibodies including anti‐gliadin (AGA), anti‐endomysium (EmA), anti‐transglutaminase (tTGA) and anti‐nuclear (ANA) antibodies in the sera of patients with unexplained painful sensory neuropathies in order to identify other potentially treatable disorders. We tested the sera of 10 patients (4M; 6F) previously investigated for other causes of neuropathies, including anti‐nerve, onconeural, anti‐extractable nuclear, anti‐neutrophil cytoplasmic, anti‐thyroglobulin (TgA) and anti‐peroxidase (TPOA) antibodies. We found the presence of AGA positivity in 4 patients (40%), ANA in 7 (70%) and AGA + ANA in 4 (40%), two of whom were negative for celiac disease by gastrointestinal biopsy. None of the patients had EmA positivity. Three (30%) had TgA and TPOA and none had anti‐nerve or onconeural antibodies. Whether the presence of circulating autoantibodies in patients with unexplained painful neuropathy reflects an autoimmune involvement which may be amenable to immune therapy and not only to symptomatic treatment remains to be established. 相似文献
37.
38.
39.
Diet and cancer prevention: the fiber first diet 总被引:3,自引:0,他引:3
Diet can play a major role in cancer prevention. The international
differences in cancer incidence are largely accounted for by lifestyle
practices that include nutrition, exercise, and alcohol and tobacco use.
About 50% of cancer incidence and 35% of cancer mortality in the U.S.,
represented by cancers of the breast, prostate, pancreas, ovary,
endometrium, and colon, are associated with Western dietary habits. Cancer
of the stomach, currently a major disease in the Far East, relates to
distinct, specific nutritional elements such as excessive salt intake. For
these cancers, information is available on possible initiating genotoxic
factors, promoting elements, and prophylactic agents. In general, the
typical diet in the United States contains low levels of the potent
carcinogenic agents, heterocyclic amines, formed during the cooking of
meats. It provides only about half the potent appropriate fiber intake and
is high in calories. About twice as many calories as would be desirable
come from fat, certain kinds of which enhance the development of cancers.
Other foods with functional properties, such as soy products and tea, can
be beneficial. To achieve reduction in risk of certain cancers, diet must
be optimized, primarily to reduce caloric intake and the fat component. The
latter should be 20% or less of total caloric intake and fiber should be
increased to 25- 35 g per day for adults. One approach to achieving these
goals is the Fiber First Diet, a diet designed around adequate fiber intake
from grains, especially cereals, vegetables, legumes, and fruits, which
thereby reduces both calorie and fat intake. Such dietary improvements will
not only reduce cancer and other chronic disease risks, but will contribute
to a healthy life to an advanced age. A corollary benefit is a lower cost
of medical care.
相似文献
40.
GM Durbin NJ Hunter N McIntosh EO Reynolds PD Wimberley 《Archives of disease in childhood》1976,51(3):163-169
A controlled trial of elective intervention with continuous inflating pressure (CIP) was performed in infants with severe hyaline membrane disease who weighed more than 1000 g at birth. Infants entered the trial if their arterial oxygen tension (PaO2) fell below 60 mmHg while breathing a fractional inspired oxygen concentration (F1O2) greater than 0-95. 11 out of 12 infants in the CIP-treated group and 10 out of 12 in the control group survived. 7 treated and 6 control infants required mechanical ventilation. When CIP was started the Pao2 of the treated infants increased, and they breathed high concentrations of oxygen for a significantly shorter period than the control infants. During the 31-month duration of the trial 107 other infants with severe hyaline membrane disease were admitted who did not meet the criteria for entry to the trial. 37 survived after breathing high concentrations of oxygen (F1O2 greater than 0-60) spontaneously without any ventilatory assistance, and the remaining 70 infants were already being ventilated on their arrival in the unit, usually because they had required mechanical ventilation during transfer from other hospitals. The neonatal survival rate for those infants born in this hospital during the study period was 88% (50 out of 57 infants) and for those referred from other hospitals it was 69% (51 out of 74 infants). The maximum further increase in overall survival rate that might have been achieved in our population of infants if CIP had been initiated very early in the course of the illness was 5%--i.e. from 77% (101/131) to 82% (107/131). 相似文献