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991.
AIM: To assess whether mean daily intake of copper or maximal concentration of copper in drinking water is related to the incidence of diarrhoea and vomiting among young children. METHODS: Mean daily intake of copper from drinking water was estimated prior to episodes of diarrhoea among 430 children aged 9 to 21 mo. A total of 4703 samples of tap water were collected in the homes of the children. The mean daily intake of copper and the maximal concentration of copper in samples of consumed water were used as measures of exposure. The cumulative incidence of acute diarrhoea and vomiting was studied during 12 wk of follow-up. Cases of diarrhoea caused by viral and bacterial infections were identified. RESULTS: The median copper level of the mean value for each child was 0.61 mg/L with 10th and 90th percentiles of 0.04 and 1.57 mg/L. Among the 430 children, 43 had episodes of acute diarrhoea, of which 23 had no identified viral or bacterial origin, and vomiting was reported in 95 children. No significant associations were found between daily intake of copper or maximal concentration of copper in drinking water and the risk of diarrhoea or vomiting. CONCLUSION: There is unlikely to be a strong association between daily intake of copper or maximal concentration of copper in drinking water and the risk of diarrhoea or vomiting within the range of copper intakes/concentrations studied.  相似文献   
992.
In communities where early age of childbearing is common and HIV prevalence is high, adolescents may place themselves at risk of HIV because positive or ambivalent attitudes towards pregnancy reduce their motivation to abstain from sex, have sex less often or use condoms. In this study, we analyse cross-sectional survey data from KwaZulu Natal, South Africa, to explore whether an association exists between the desire for pregnancy and perceptions of HIV risk among 1,426 adolescents in 110 local communities. Our findings suggest that some adolescents, girls more than boys, were more concerned about a pregnancy if they lived in environments where youth were perceived to be at high risk of HIV infection. The probability that pregnancy was considered a problem by boys was positively correlated with the proportion of adult community members who thought youth were at risk of acquiring HIV, and for girls by the proportion of peers in the community who thought youth were at risk of HIV. We also found that becoming pregnant would be a bigger problem for the African girls than the white and Indian girls. The analysis suggests that for some adolescents, in addition to effects on educational and employment opportunities, the danger of HIV infection is becoming part of the calculus of the desirability of a pregnancy.  相似文献   
993.
A study of maternal complications after elective Caesarean section in HIV-infected women was carried out from January 1999 to April 2001. The control group consisted of all the seronegative pregnant women who underwent the elective Caesarean section during the study period. The study group was divided into two subgroups. Subgroup 1 patients were given 600 mg zidovudine (ZDV) orally and 300 mg lamivudine (3TC) daily from 34 to 38 weeks' gestation. Subgroup 2 patients were given 600 mg ZDV orally daily from 34 to 38 weeks' gestation and 150 mg nevirapine orally on the morning of the Caesarean section day. In both groups, the elective Caesarean section was carried out at 38 weeks' gestation and ZDV syrup (2 mg/kg) was given orally to the newborn immediately in the operating theatre and then every 6 h for 4 weeks. No statistically significant differences in maternal complications were found between the HIV-infected and non HIV-infected women.  相似文献   
994.
楼超华  沈燕  涂晓雯  高尔生 《生殖与避孕》2003,23(5):283-290,298
目的:评价社区性与生殖健康教育和服务对未婚青(少)年性相关态度的影响。方法:在上海市某区两个乡镇开展以社区为基础的持续20个月干预性研究,干预组和对照组分别为15~24岁未婚青(少)年1220名和1007名。干预活动包括发放宣教材料、播放教育录像、组织讲座和小组讨论、提供咨询和避孕服务。通过干预前后的问卷调查对干预项目的效果进行。结果:干预组和对照组对象对绝大多数性相关问题的态度与看法在基线调查时无明显差别。两组总随访率为92%。干预后调查发现,干预组对象对男、女性婚前性行为持赞成态度的比例明显低于对照组,而持理解态度的比例高于对照组;认为婚前性行为对男、女未婚青年“有不良影响”的比例高于对照组。此外,干预组对象的安全性行为和自我保护意识增强。多因素分析结果显示,在调整了其它可能影响对婚前性行为和未婚妊娠态度的因素后,干预仍是影响对象对婚前性行为和未婚妊娠态度的因素之一。结论:以社区为基础开展的未婚青(少)年性与生殖健康教育和服务可在一定程度上改变青(少)年的性观念,使他们对性相关问题持更为积极和理性的态度。  相似文献   
995.
OBJECTIVE: To determine the endometrial safety of 2 years of treatment with lower doses of continuous combined conjugated equine estrogens (CEE) and medroxyprogesterone acetate (MPA). DESIGN: Randomized, double-blind, placebo-controlled, multicenter metabolic and osteoporosis substudy of the Women's Health, Osteoporosis, Progestin, Estrogen (Women's HOPE) study. SETTING: Nineteen study centers across the United States. PATIENT(S): Healthy, postmenopausal women (n = 822) with an intact uterus were recruited. INTERVENTION(S): Patients received CEE 0.625, CEE 0.625/MPA 2.5, CEE 0.45, CEE 0.45/MPA 2.5, CEE 0.45/MPA 1.5, CEE 0.3, CEE 0.3/MPA 1.5 (all doses mg/day), or placebo for 2 years. Endometrial biopsies were evaluated at baseline and years 0.5, 1, 1.5, and 2 using a centralized protocol. MAIN OUTCOME MEASURE(S): Efficacy of lower doses of CEE/MPA in reducing the incidence of endometrial hyperplasia rates associated with unopposed estrogen (E). RESULT(S): No cases of endometrial hyperplasia were seen in the four CEE/MPA groups. For the CEE-alone groups, a dose-related increase in incidence rates from 3.17% (CEE 0.3 mg) to 27.27% (CEE 0.625 mg) was seen at 2 years. The number of cases increased from year 1 to year 2. For the CEE-alone groups, the incidence rates and types of hyperplasia diagnosed varied among the pathologists. CONCLUSION(S): Two years of treatment with lower doses of CEE/MPA provided endometrial protection comparable to that seen with commonly prescribed doses. These regimens should be considered for postmenopausal women who are candidates for hormone therapy.  相似文献   
996.
Summary ¶The aims of the Polish survey were to assess efficacy of screening for depression in gynecological practice and to estimate prevalence of depressive disorders in midlife women visiting gynecologists. The study included 2262 female outpatients aged 45–55, who were screened by 120 gynecologists throughout Poland. Patients completed the Becks Depression Inventory (BDI) and were assessed by gynecologists to verify the presence of symptoms of a current Depressive Episode according to ICD-10 diagnostic criteria. Patients who obtained a score of 12 points or more on the BDI were referred for psychiatric evaluation, including the modified version of Mini International Neuropsychiatric Interview (MINI). The study showed that gynecologists in Poland are able to perform screenings for depression effectively in outpatient settings. Results also suggested that about 19% of women aged 45 to 55 years visiting gynecologists may suffer from depressive disorders.Received December 4, 2003; accepted May 9, 2003 Published online July 3, 2003  相似文献   
997.
We report the case of a 29-yr-old man with multiple myeloma who presented initially with subcutaneous plasmacytomas. These are the atypical features of his clinical course: (a) age of the patient; (b) unusual clinical presentation with subcutaneous masses; (c) lack of 'typical' features of multiple myeloma (renal failure, hypercalcaemia, and bone pain); and (d) disease progression as extramedullary recurrences.  相似文献   
998.
OBJECTIVES: To examine trends in sex ratios for different manifestations of coronary disease. DESIGN: National Swedish registers on hospital discharges and cause-specific deaths were used to calculate age- and sex-specific trends and sex ratios for coronary admissions and deaths. SETTING: Nineteen Swedish counties, average population 4.8-5.1 million in the investigated age groups. SUBJECTS: All patients aged 25-84 years with first hospital admissions or deaths as a result of coronary heart disease in 1984-99, in total 432,871 cases. MAIN OUTCOME MEASURES: Ratio men/women and rates (per 100,000) of acute myocardial infarction (AMI), acute admissions for angina and total of all acute admissions for any coronary disease. RESULTS: Below age of 65 years AMI incidence decreased more for men than for women and rates of acute admissions for angina increased more in women than in men. In men and women above 65 years trends were almost identical. In 1984-87 the ratio men/women with respect to myocardial infarction was 5.6 at age 25-44 years, but decreased to 3.7 in 1996-99. Corresponding sex ratios for angina decreased from 3.2 to 1.8 and for total coronary heart disease from 4.7 to 2.8. Amongst men and women aged 45-54 years, the sex ratio with respect to myocardial infarction decreased from 5.6 to 4.1, for angina from 2.4 to 1.7 and for total acute coronary disease from 4.2 to 2.7. Ratios men/women decreased less at higher ages and remained unchanged throughout the period in the oldest age group. CONCLUSIONS: Overall, we found decreasing sex ratios at ages below 65, but above age 65 years trends in men and women were similar. These developments could be due to changing criteria for admission and diagnosis, but true differences in the clinical manifestation of coronary disease, possibly in response to secular trends in risk factor levels, cannot be excluded.  相似文献   
999.
Aims To model consumption patterns and problems associated with alcohol, cannabis, ecstasy, amphetamine and cocaine hydrochloride use in a non‐treatment sample of young polysubstance users. Design A cross‐sectional survey of 364 16–22‐year‐old (56.3% male) polysubstance users recruited and interviewed by peer interviewers. Measurements Structured questionnaires were used to gather identical datasets on the five target psychoactive substances, recording patterns of substance use; adverse consequences from use; negative effects; functions for substance use; and perceived peer use. Findings Functions for substance use strongly predicted intensity of use in all five substances when peer use, age of first use and demographics were controlled, explaining an additional 11–19% of the variance in scores. Functions also explained an average of 22% of the variance in problem scores over and above the effects of background variables and current intensity of use. In particular, functions concerned with relief from negative mood states were strong predictors of problem scores in alcohol, cannabis and cocaine. Conclusions The potential implications of using a functional approach to explaining and responding to substance use are considerable. This could help to enhance our understanding of how experimental substance use becomes regular and how regular use becomes problematic, and could thus inform prevention, education and intervention efforts.  相似文献   
1000.
Androgen supplementation in older women: too much hype,not enough data   总被引:3,自引:0,他引:3  
Androgen supplementation in women has received enormous attention in the scientific and lay communities. That it enhances some aspects of cognitive function, sexual function, muscle mass, strength, and sense of well-being is not in question. What is not known is whether physiological testosterone replacement can improve health-related outcome in older women without its virilizing side effects. Although it is assumed that the testosterone dose-response relationship is different in women than in men and that clinically relevant outcomes on the above-mentioned effects can be achieved at lower testosterone doses, these assumptions have not been tested rigorously. Androgen deficiency has no clear-cut definition. Clinical features may include impaired sexual function, low energy, depression, and a total testosterone level of less than 15 ng/dL, the lower end of the normal range. Measurement of free testosterone is ideal, because it provides a better estimate of the biologically relevant fraction. It is not widely used in clinical practice, because some methods of measuring free testosterone assay are hampered by methodological difficulties. In marked contrast to the abrupt decline in estrogen and progesterone production at menopause, serum testosterone is lower in older women than in menstruating women, with the decline becoming apparent a decade before menopause. This article reviews testosterone's effects on sexual function, cognitive function, muscle mass, body composition, and immune function in postmenopausal women.  相似文献   
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