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91.
Objective To investigate the mechanism of enhanced large conductance calciumactivated potassium channel currents (BK) in coronary smooth muscle cells (SMCs) by docosahexaenoic acid (DHA). Methods Coronary SMCs were isolated by enzyme digestion. Potassium channels in coronary SMCs were identified by applications of different potassium blockers. Effects of DHA and its metabolite 16,17-epoxydocosapentaenoic acid (16,17-EDP) on BK channels in the absence and presence of cytochrome P450 epoxygenase inhibitor SKF525A were studied by patch clamp in whole-cell configuration. Results BK channels were widely distributed in SMCs, and BK currents in normal SMCs accounted for (64.2±2.7)%of total potassium currents(n =20). DHA could activate BK channels, and its 50% effective concentration (EC50) was (0.23±0.03)μmol/L, however, the effect of DHA on BK channels was abolished after SMCs were incubated with cytochrome P450 epoxygenase inhibitor SKF525A. 16,17-EDP, a metabolite of DHA, could reproduce the effects of DHA on BK channels, and its EC50 was (19.7± 2.8) nmol/L.Conclusion DHA and metabolites can activate BK channels and dilate coronary arteries through activating cytochrome P450 epoxygenase pathway.  相似文献   
92.
Aim: This study aimed to evaluate the immediate and long‐term effects of a 12 week problem‐solving (PS) counseling program to facilitate intensified walking with machinery monitoring on persons with type 2 diabetes mellitus in Korea. Methods: The study used a quasi‐experimental design. The participants were 57 patients with diabetes from three endocrinology or internal medicine clinics in an urban city of South Korea. Moderate‐intensity walking and PS counseling were recommended to both groups. The difference between the two groups was whether the intensity of the exercise was monitored by an ambulatory heart rate monitor (experimental group) or was self‐regulated (comparison group). Those programs were evaluated in relation to BMI, glycemic control (blood glucose level, glycosylated hemoglobin [HbA1c]), a vascular complication index (total cholesterol, high‐density lipoprotein cholesterol, low‐density lipoprotein cholesterol, triglycerides, tissue plasminogen activator [t‐PA], plasminogen activator inhibitor‐1 [PAI‐1], Parma Cardiovascular Risk Index), and coping strategies at 3 and 6 months. Results: The experimental group members showed dramatic decreases in their glucose and HbA1c levels at 3 months. The values of t‐PA decreased significantly at baseline, compared to at 3 months. The levels of PAI‐1 continuously declined and the Parma Cardiovascular Risk Index score did not change significantly from baseline to at 3 months, but showed significant effects at 6 months. Conclusion: A combined program of intensified walking, using a heart rate monitor, with PS counseling is more helpful to prevent complications than self‐regulated exercise for persons with type 2 diabetes in Korea.  相似文献   
93.
Aim: To carry out a pilot study to investigate the effect of short‐term oral probiotic administration on the metabolism of sulfasalazine (SSZ) in patients with rheumatoid arthritis (RA) stabilized on SSZ. Methods: Twelve subjects with RA taking stable doses of SSZ for a minimum of 3 months prior to the study, received a probiotic preparation contained three strains of bacteria (1.8 × 109 CFU/day) twice daily for 1 week. Single point blood and 12‐h urine samples were taken before and after probiotic treatment and 3 weeks following discontinuation of probiotics, for determination of SSZ and its metabolites. The presence of the probiotic bacteria in the feces of patients was investigated by denaturing gradient gel electrophoresis (DGGE). Results: Adverse events recorded were three instances of gastrointestinal disturbance and one flare of RA. Plasma and urinary levels of SSZ and its metabolites showed no statistically significant changes after probiotic administration and the incidence of gastrointestinal disturbance did not appear to be ascribed to higher sulfapyridine plasma levels. Probiotic‐specific DGGE bands were detected in the feces of some patients after the treatment period. Conclusions: Short‐term treatment of RA patients with a multi‐strain probiotic did not significantly influence SSZ metabolism as has been demonstrated in animal models.  相似文献   
94.
95.
1. The in vitro metabolism of the new insecticide flupyrazofos was studied using rat liver microsomes. Two metabolites were produced and identified as O, O -diethyl O -(1- phenyl-3-trifluoromethyl-5-pyrazoyl) phosphoric acid ester (flupyrazofos oxon) and 1- phenyl-3-trifluoromethyl-5-hydroxypyrazole (PTMHP) based on UV and mass spectral analysis. 2. Cytochrome P450 oxidatively converted flupyrazofos to flupyrazofos oxon, a major metabolite and phenobarbital-induced microsomes increased this desulphuration by 8- fold. 3. Flupyrazofos oxon was converted to PTMHP with a half-life of 47 8?min by chemical hydrolysis and this conversion also proceeded non-enzymatically under our microsomal incubation conditions.  相似文献   
96.
Background: The aim of this study was to evaluate the efficacy of ondansetron and ramosetron in the reduction of post‐operative nausea and vomiting (PONV) associated with patient‐controlled analgesia (PCA) after cardiac surgery. Methods: A total of 320 patients scheduled for elective cardiac surgery were enrolled. Patients were randomly assigned to one of four treatment regimens (n=80 in each group): no prophylactic antiemetics (group P); intravenous (i.v.) ondansetron 4 mg at the end of surgery and 12 mg added to PCA (group O); i.v. ramosetron 0.3 mg at the end of surgery and no antiemetics added to PCA (group R1); and i.v. ramosetron 0.3 mg at the end of surgery and 0.6 mg added to PCA (group R2). Results: The incidence of PONV during the 48‐h post‐operative period was lower in groups O (46%), R1 (54%), and R2 (35%) compared with group P (71%, P<0.001). The incidence and severity of nausea were lower in groups O, R1, and R2 than in group P during the 24‐h post‐operative period, whereas the incidence and severity of nausea during 24–48 h after surgery were lower in groups O and R2, but not in group R1, than in group P. Compared with group P (53%), the frequency of rescue antiemetic usage was significantly lower in groups O (34%) and R2 (29%), but not in group R1 (43%). Conclusion: The addition of either ondansetron or ramosetron to PCA can reduce the incidence of PONV during 48 h after cardiac surgery.  相似文献   
97.
Aim Motor skill impairment is a common negative outcome in children born preterm who do not develop cerebral palsy (CP). This study aimed to conduct a systematic review of current data to provide an accurate estimate of the prevalence of non‐CP motor impairment in preterm children at school age. Method We searched the Medline, PubMed, and PsycInfo databases and relevant journals to identify all studies published post‐1990 that reported the prevalence of motor impairment in school‐aged children born preterm (<37wks’ gestation) using standardised motor assessment batteries. We applied a range of exclusionary criteria, with 11 studies included in the final analyses. We identified two levels of motor impairment commonly reported – mild–moderate and moderate – and conducted a random effects meta‐analysis to produce a prevalence estimate for each. Results The pooled estimate for mild–moderate impairment in preterm children was 40.5/100. and for moderate motor impairment the estimate was 19.0/100. There was also a trend for lower motor impairment levels in samples born before 1990 compared with those born after 1990. Interpretation Children born preterm are at increased risk of motor impairment, with prevalence three to four times greater than in the general population. This highlights the need for improved surveillance and intervention strategies in this group of children.  相似文献   
98.
Objective To examine the relationship of single-nucleotide polymorphisms(SNPs)in candidate genes with the lipid responses to simvastatin.Methods Chinese patients were treated with simvastatin 40 mg daily for at least 6 weeks.20 SNPs in 11 genes were genotyped.Results 95 patients age(mean±SD)57.5±10.6 years completed the treatment.The Adiponectin 45T>G polymorphism was significantly related to absolute reductions in total cholesterol(TC)and LDL-cholesterol with a trend(P=0.053)for percentage reductions in TC(TT∶TG∶GG=-38.4%∶-35.6%∶-32.6%).Similar findings were seen with LDL-Receptor(LDLR)SNPs(2052T>C and 1866C>T)with absolute reductions in TC and LDL-cholesterol significantly associated.The Breast Cancer Resistance Protein(ABCG2)421C>A polymorphism was related(P<0.05)to HDL-cholesterol response(CC∶CA∶AA=+0.50%∶-5.73%∶-11.41%).Conclusions Adiponectin,LDLR and ABCG2 SNPs had some influence on the lipid responses to simvastatin.  相似文献   
99.
目的研究0.5%心居康杀白蚁饵剂对台湾乳白蚁(Coptotermes formosanusShiraki)的防治效果。方法2001年在无锡和杭州进行了试验研究,试验分实验室和建筑物现场试验两个部分进行。结果无论是地上(AG)投药,还是地下(IG)投药,不论是室外投药还是室内投药,消灭一个族群需要35~69 d,平均(54.75±12.25)d。消灭一个族群只需要0.5%心居康杀白蚁饵剂48~150 g,平均(103.05±28.9)g,折合有效成分(0.52±0.146)g。结论0.5%心居康杀白蚁饵剂均可以达到消灭台湾乳白蚁的整个族群。  相似文献   
100.
Abstract In the present economic climate and with increasing expenditure on neonatal intensive care, there has been a demand for economic evaluation and justification of neonatal intensive care programmes. This study assesses the inhospital costs of neonatal intensive care. Fixed and variable costs were calculated for services and uses of an Intensive/Special Care Nursery for the year 1985 and corrected to 1987 Australian dollar equivalents. Establishing a new neonatal intensive care unit of 43 cots in an existing hospital with available floor space including operating costs for a year were estimated in Australian dollars for 1987 at $6 408 000. Daily costs per baby for each level of care were $1282 ventilator, $481 intensive, $293 transitional and $287 recovery, respectively. The cost per survivor managed in the Intensive/Special Care Nursery in 1985 showed the expected inverse relationship to birthweight being $2400 for > 2500 g, $4050 for 2000–2500 g, $9200 for 1500–1999 g, $23 900 for 1000–1499 g and $63 450 for < 1000 g. Further analysis for extremely low birthweight infants managed in 1986 and 1987 demonstrated costs per survivor of $128 400 for infants < 800 g birthweight and $43 950 for those 800–999 g. This methodology might serve as a basis for further accounting and cost-evaluation exercises.  相似文献   
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