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991.
Large number of epidemiological studies to know the effect of air pollution on the general mortality and morbidity, and the cardiopulmonary morbidity and mortality are concentrated in USA and Europe. Regional differences in air pollution necessitate regional level health effects studies. Present study is a cross sectional pilot study from India, an Asian country. A sample of population from an industrial town 'Mandi Gobindgarh' and a nonindustrial town 'Morinda' were selected. A cross-sectional household survey was done in both the towns. One hundred subjects were selected from each of the towns. Ambient air quality data was collected for both towns over a period of 10-months to assess seasonal variations. In the present study the average PM10 (particulate matter with < or = 10 microm aerodynamic diameter) levels in Morinda were 99.54 microg/m3 and in Mandi Gobindgarh 161.20 microg/m3. As per NAAQS the permitted levels of PM10 is 50 microg/m3 taken as annual average (arithmetic mean). Elemental analysis of the aerosol samples found the concentration levels to be higher in Mandi- Gobindgarh than Morinda. The population in Gobindgarh shows a higher prevalence of symptoms of angina and cardiovascular disease considered in the study as compared to Morinda. When the same data is viewed in terms of male and female population, the female population is found to show these symptoms marginally higher than their counterparts. Considering the results of present study it can be stated that the increased levels of different pollutants and the higher prevalence of cardiovascular symptoms in Mandi-Gobindgarh (Industrial town) than the Morinda (Non-Industrial town) is because of the association of PM pollution with cardiovascular diseases. Keeping in view the current status of literature, further studies in this direction are needed in a country like India. Such data will also be globally relevant.  相似文献   
992.
993.
AIM: This paper is a report of a study to explore perceptions of ageing, dementia and ageing-associated mental health difficulties amongst British people of Punjabi Indian origin. BACKGROUND: People from ethnic minorities are often under-represented in mental health services. Contributing factors may include lack of knowledge of dementia in these communities, lack of detection in primary care, expectations of family care and lack of appropriate services. For this to change, greater knowledge is needed about awareness and conceptualization of dementia in minority ethnic communities. METHOD: A focus-group study was conducted between 2001 and 2003 with 49 English-, Hindi- and Punjabi-speaking British South Asians, aged 17-61 years. Views of ageing and ageing-associated difficulties were explored in initial groups. In a second set of groups, vignettes were used for more specific exploration of awareness and understanding of dementia. Data were subjected to thematic analysis. FINDINGS: Ageing was seen as a time of withdrawal and isolation, and problems as physical or emotional; cognitive impairment was seldom mentioned. There was an implication that symptoms of dementia partly resulted from lack of effort by the person themselves and possibly from lack of family care. Therefore people should overcome their own problems and family action might be part of the solution. There was a sense of stigma and a lack of knowledge about mental illness and services, alongside disillusionment with doctors and exclusion from services. CONCLUSION: Health promotion and health interventions delivered with respect for the cultural context are needed, as well as education of healthcare professionals about South Asian conceptualizations of dementia.  相似文献   
994.
995.
The role of reactive oxygen species (ROS) as signaling agents is increasingly appreciated. Studies of ROS functions in the central nervous system, however, are only in their infancy. Using fast-scan cyclic voltammetry and fluorescence imaging in brain slices, the authors discovered that hydrogen peroxide (H2O2) is an endogenous regulator of dopamine release in the dorsal striatum. Given the key role of dopamine in motor, reward, and cognitive pathways, regulation by H2O2 has implications for normal dopamine function, as well as for dysfunction of dopamine transmission. In this review, data are summarized to show that H2O2 is a diffusible messenger in the striatum, generated downstream from glutamate receptor activation, and an intracellular signal in dopamine neurons of the substantia nigra, generated during normal pacemaker activity. The mechanism by which H2O2 inhibits dopamine release and dopamine cell activity is activation of ATP-sensitive K+ (KATP) channels. Characteristics of the neuronal and glial antioxidant networks required to permit H2O2 signaling, yet prevent oxidative damage, are also considered. Lastly, estimates of physiological H2O2 levels are discussed, and strengths and limitations of currently available methods for H2O2 detection, including fluorescence imaging using dichlorofluorescein (DCF) and the next generation of fluorescent probes, are considered.  相似文献   
996.
Purpose  Acute liver failure (ALF) is characterized by a rapid and massive destruction of hepatocytes. The role of oxidative stress in perpetuating the injury is undefined and may be a potential therapeutic target. Our aim was to study serial variation in oxidative stress and antioxidant status in patients with ALF. Methods  The study involved a prospective case–control study set in a tertiary care referral center. Thirty-two consecutive patients admitted with ALF were included with 23 healthy controls for comparison. Level of systemic oxidative stress as defined by superoxide dismutase (SOD), lipid peroxidation products (thiobarbituric acid reactive derivatives [TBARS]), and the total antioxidant capacity as the ferric reducing ability of plasma (FRAP) was measured at baseline on days 3 and 7. Results  The patients were aged 24 years (range 13–60 years) and included 20 females. Thirteen (40.6%) patients died. Patients with ALF had significantly increased systemic oxidative stress at presentation, as reflected by higher levels of SOD (P < 0.001) and TBARS (P < 0.001) than controls. Both TBARS levels and FRAP decreased progressively from admission to the end of first week among the survivors (P = 0.004 and 0.015, respectively). The antioxidant status reflected by FRAP (P = 0.001) was significantly lower in ALF patients than controls. No relation was found between the level of oxidative stress and the mortality or complications. Conclusion  A high level of systemic oxidative stress exists in ALF, with depletion of antioxidant reserves. Further studies are needed to define the clinical correlation of the large pro-oxidant burden.  相似文献   
997.
OBJECTIVE: To determine whether an isolated echogenic intracardiac focus in the fetal heart in the mid-trimester (16-24 weeks) in women aged 18-34 years of age is associated with trisomy 21. METHOD: This was a prospective population-based observational study. A search of all obstetric sonograms performed in our region from January 1997 to December 1999 was carried out. From 12,373 pregnancies we identified 267 cases of echogenic foci in the fetal heart. Trisomy 21 was detected in 38 deliveries (0.31%). An echogenic focus was seen in 193 of the 9167 women < 35 years of age who had an obstetric sonogram at 16-24 weeks' gestation, and an echogenic focus was seen in 67 of the 1968 women > 35 years. The study group comprised the 149 women aged 18-34 years who had an echogenic focus in the fetal heart as the only abnormality at an obstetric sonogram performed at 16-24 weeks' gestation. RESULTS: There were no abnormal outcomes or cases of trisomy 21 among the 149 pregnancies with an echogenic focus as an isolated finding in women aged 18-34 years (0% (95% confidence interval, 0.00-2.43)). The prevalence of isolated echogenic focus was 1.6% for women < 35 and 1.8% for women >or= 35 years old. Of the 25 fetuses with trisomy 21 undergoing an obstetric sonogram at any gestational age, five (20%) had an echogenic focus. An isolated echogenic focus was present in one fetus with trisomy 21 seen at 26 weeks' gestation in a 17-year-old mother. Echogenic foci were single and in the left ventricle in 84.7% of cases. CONCLUSION: An isolated echogenic focus in the fetal heart at mid-trimester ultrasound in women aged 18-34 years is not associated with increased risk for trisomy 21.  相似文献   
998.

Background

The aim of the study was to study the four week patency rates of the reconstructed neo middle hepatic vein specifically using the explant portal vein (PV) in right hemiliver live donor liver transplantation (LDLT). We hypothesized that short term patency of the neo-MHV should result in good graft and patient outcomes.

Methods

Pre, intra and post operative variables were prospectively collected for 88 consecutive patients undergoing right hemiliver LDLT from January 2014 to October 2015.

Results

Explant PV was used to reconstruct neo-MHV in 76 (86.4%, 76/88) patients. Neo MHV patency rate at 28 days with explant PV was 89.4% (59/66) and with other conduit (PTFE) was 90.9% (10/11). All occlusions were detected after 7 days. There was no impact of the patency of the neo-MHV on the incidence of early allograft dysfunction, sepsis, rejection, morbidity or mortality, despite the contribution of the anterior sector to the graft volume being more than 50% in close to two-thirds of patients.

Conclusion

The reconstructed neo-MHV has excellent short term patency rates at 4 weeks. Perhaps due to the absence of early occlusions, there was no impact on graft or patient outcomes in the study population.  相似文献   
999.

Objective

Primary: To determine the incidence of congenital malaria in a cohort of pregnant women in a hyper-endemic area of central India. Secondary: (1) To find out the placental weight and placental malaria positivity, and to assess fetal and neonatal outcome in terms of survival, mean hemoglobin and mean birth weight.

Design

Prospective observational study.

Setting

Maternity and neonatal ward of a tertiary level hospital attached to a medical college located in Rewa, Madhya Pradesh, India.

Participants

Near term and term pregnant women admitted in the maternity ward with a singleton pregnancy, whose neonates were available for examination till at least 6 hours after birth.

Methods

Thick and thin blood smear were examined for malarial parasites from mothers prior to delivery. Based on the results of peripheral smear they were divided into ‘exposed group’ (peripheral smear positive for malaria parasite) and unexposed group’ (smear negative for malaria parasite). These groups were then followed prospectively till delivery and subsequently till the mother and the neonates were discharged from the hospital.

Outcome variables

Primary: Presence of asexual parasite in neonate. Secondary: Placental weight, presence of asexual malarial parasite in placenta, still births, early neonatal deaths, mean birth weight and mean hemoglobin.

Results

Seventy-two (35.5%) of 203 blood smears of near term and term pregnant women were found positive for malaria parasite (60 P. vivax and 12 P. falciparum); rest 131 comprised the unexposed group. Six (2.95%) neonates had parasitemia (4 P. vivax and 2 P. falciparum). Of the 203 smears made from placental blood, 24 (11.8%) were positive for malaria parasite. The mean (SD) birth weight [2300 (472) g vs 2430 (322) g; P=0.98], proportion of preterm babies (6.9% vs 8.4%, P=0.71), incidence of still birth (4.2% vs 3.0%, P=1.0) and early neonatal death (2.8% vs 3.0%, P=1.0) were not significantly different between the exposed and unexposed group.

Conclusions

The incidence of congenital malaria is low despite high maternal smear positivity for malaria.  相似文献   
1000.
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