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101.
The marine-derived cembranoid sarcophine (1) and its sulfur-containing semisynthetic derivatives (26) were evaluated for anticancer potential using cell cycle progression markers. No effect on MCF-7 cell viability or apoptosis was seen with these derivatives at concentrations of up to 100 μM after 72 h of incubation. At 100 μM, sarcophine and its derivatives 25 arrested the MCF-7 cells in G0/G1 phase, with concomitant decrease in the cell populations at S and G2+M phases. MDA-MB-231 cells were not responsive to any of the derivatives. Our preliminary results suggest that the sulfur-containing derivatives of sarcophine, especially 2 and 3, show potent and cell-specific antiproliferative activity.  相似文献   
102.
A study of aplastic anemia in children in a period of June 1980 to June 1989 was done to evaluate the pattern of aplastic anemia in children. The cases consisted of 55 children, 30 males (54.55%) and 25 females (45.45%). Most of the patients (47.27%) were found in the age group of 10 to 15 years. The complaints were paleness (90.91%), fever (56.45%) and bleeding (52.72%). The hemoglobin concentration was 4.25 +/- 1.17 g/dl (mean +/- SD), and the thrombocytopenia was generally severe. Prednisone or combination of prednisone and oxymethalone was given in addition to blood transfusions, antibiotics and vitamins. The outcome was difficult to evaluate because of the irregularity of treatments. Of the 55 children, 9 (18.02%) contracted leukemia after 1-5 months.  相似文献   
103.
Objectives: To estimate the prevalence of work related asthma and work related wheezing in United States workers. To identify high risk industries that could be targeted for future intervention. To determine the population attributable risk of work related asthma and work related wheezing.

Methods: The third national health and nutrition examination survey, 1988–1994 (NHANES III) was analyzed to determine the prevalence of work related asthma and wheezing and to identify initially defined industries at risk among United States workers aged 20 and older. Separate logistic models were developed with work related asthma and work related wheezing as outcomes. Work related asthma was defined as affirmative response to questions on self reported physician diagnosed asthma and work related symptoms of rhinitis, conjunctivitis, and asthma. Work related wheezing was defined as affirmative response to questions on self reported wheezing or whistling in the chest in the previous 12 months and work related symptoms of rhinitis, conjunctivitis, and asthma. All analyses were adjusted for age, sex, smoking, and atopy.

Results: The prevalence of work related asthma was 3.70% (95% confidence interval (95% CI) 2.88 to 4.52) and the prevalence of work related wheezing was 11.46% (95% CI 9.87 to 13.05). The main industries identified at risk of work related asthma and wheeze included the entertainment industry; agriculture, forestry, and fishing; construction; electrical machinery; repair services; and lodging places. The population attributable risk for work related asthma was 36.5% and work related wheezing was 28.5%.

Conclusions: The findings provide impetus for further research and actions by public health professionals which prioritise occupational asthma on the public health agenda. Future intervention strategies need to be developed for effective control and prevention of asthma in the workplace.

  相似文献   
104.
Incidence of cochlear involvement in hyperbilirubinemic deafness   总被引:6,自引:0,他引:6  
Neonatal hyperbilirubinemia remains an important cause of childhood deafness, especially in developing countries. After neonatal hyperbilirubinemia, the auditory neural pathways, cochlea, or both may be affected. In this study, we aimed to determine the incidence of cochlear impairment and the appropriate means of hearing screening in hyperbilirubinemic neonates. A retrospective review of 1,032 pediatric patients with hearing loss revealed 67 cases (6.5%) of severe hyperbilirubinemia in the neonatal period. Thirty of these patients had neonatal hyperbilirubinemia as the single identifiable risk factor for hearing loss. In 26 of 30 cases (87%), otoacoustic emissions (OAEs) were absent, whereas in the remaining 4 cases (13%), robust emissions were detected despite an absent auditory brain stem response (ABR). Auditory screening of newborns with jaundice by OAEs possesses a significant risk of undiagnosed deafness. On the other hand, if the ABR is used as the single means of screening, auditory neuropathic conditions will probably be underlooked. Therefore, we recommend dual screening of hearing by ABR and OAEs in hyperbilirubinemic newborns.  相似文献   
105.
The induction of long-term potentiation (LTP) in CA1 hippocampal area requires a rise in intracellular postsynaptic calcium. Two major calcium mechanisms may mediate the transmembrane calcium influxes that contribute to this calcium accumulation: the N-methyl-D-aspartate (NMDA) receptor channels, which are voltage dependent and have large calcium permeability and voltage-dependent calcium channels (VDCCs). We have addressed the relative contribution of these routes of calcium entry before and during LTP expression, in synaptically evoked dendritic calcium transients from a population of CA1 pyramidal neurons. Combining the use of the fluorescent calcium indicator Fura-2 with field potential measurements, we observed that the calcium transients evoked by single stimuli, during the maintenance phase of LTP, were enhanced. These transients were not affected by D-2 amino-5-phosphonopentanoate (D-APV) (50 microM), an antagonist of NMDA receptors but were reduced by approximately one-quarter, in the presence of the L-type VDCCs blocker nifedipine (10 microM). During tetanic stimulation (100 Hz, 1 s) the components triggered by the activation of those two calcium mechanisms had comparable magnitudes representing the sum about half of the intracellular calcium accumulation. Thus, following both single and high frequency stimulation, a substantial fraction of calcium entry may occur through other types of VDCCs or be due to calcium release from intracellular stores.  相似文献   
106.
107.
Serum IgG, IgA and IgM were estimated in 42 cases of carcinoma and 12 cases of fibroadenoma of breast. The results were compared with 20 healthy female controls. Results showed increased levels of serum IgA in carcinoma breast cases. This increase was statistically significant (p = 0.001) when compared with healthy controls while IgG and IgM values were found to be insignificant. Values of IgG, IgA and IgM in cases of fibroadenoma breast when compared with the controls were found to be insignificant. Statistically significant increased value of IgA was also observed in medullary carcinoma and non-metastasizing tumours when viewed separately, suggestive of good prognostic index of serum IgA level estimation in the case of carcinoma breast.  相似文献   
108.
109.
The effectiveness of fibrinolytic treatment has been shown in cases of thoracic empyema in adults. In pediatric patients experience is, however, very limited. The aim of this study was to determine the success and complication rates of fibrinolytic treatment in thoracic empyema in children. A series of 25 consecutive children who had loculated pleural empyemas that did not respond to tube thoracostomy and antibiotics is presented. Their ages ranged from 1 to 12 years (mean 4.2). There were 19 boys and 6 girls, and all epyemas were postpneumonic. The fibrinolytic agent used was urokinase in 17 and streptokinase in 8. The mean duration of fibrinolytic treatment was 4.3 days (range 2 to 8) and the mean duration of chest-tube drainage was 8.9 days (range 7 to 13). In 20 patients the fluid output from the chest tube increased significantly after instillation of the fibrinolytic agent, and these patients showed almost complete resolution of the effusion on chest radiograph and ultrasound examinations (80%). Only 5 patients developed complications: bronchopleural fistula and pleural thickening in 3, and recurrent effusion, multiloculation, and pleural thickening in other 2 which were managed by surgical intervention (20%). Our study suggests that intrapleural fibrinolytic treatment is an effective and safe adjunctive therapy in children with thoracic empyema and can obviate a thoracotomy in most cases. Accepted: 16 February 2001  相似文献   
110.
Severe nursing shortage adds to the high mortality of low birthweight babies in developing countries. To study the efficacy of maternal nursing care we conducted a prospective matched case-control study. Outcome was compared in low birthweight babies nursed by mothers (mothers' group, n = 151, cases), versus professional nurses (nurses' group, n = 211, controls). Irrespective of condition on admission, weight gain was significantly higher (p < 0.001) and overall mortality rate significantly lower (p < 0.001) in the mothers' group. Mortality was also lower in the mothers' group for babies with pathological jaundice, skin/umbilical sepsis, and no disease except low birthweight (p < 0.001). Intercurrent diarrhoea, aspiration pneumonia, and septicaemia did not differ. Training mothers to nurse their low birthweight babies can significantly reduce mortality rates and decrease workload on nurses. Policy formulation using this approach can save costs in developing countries.  相似文献   
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