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991.
The organ distribution of radioactivity following intravascular bolus injection of3H-Lys-head growth activator in rats was studied. Two minutes after injection the renal level of radioactivity exceeded the blood level 7-fold; 80% of the total activity was bound with the blood cell membranes. An analysis of chemical derivatives of the labeled peptide in the plasma by means of reverse-phase high-performance liquid chromatography revealed the presence of several groups of radioactive metabolites with different hydrophilic properties. High-performance liquid chromatography of blood extracts obtained from samples taken 0.5, 1, 1.5, 2, 31, and 60 min after injection showed the transformation of initially hydrophobic head growth activator into more hydrophilic fragments. The3H-Lys-head growth activator-associated radioactivity could be reliably detected in the blood onl during the first two minutes after injection. The half-period of blood-to-organ distribution of3H-labeled head growth activator lasted less than 30 seconds. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N o 11, pp. 466–469, November, 1994 Presented by E. I. Chazov, Member of the Russian Academy of Medical Sciences  相似文献   
992.
993.
Background: Improving lipids beyond low‐density lipoprotein cholesterol (LDL‐C) lowering with statin monotherapy may further reduce cardiovascular risk. Niacin has complementary lipid‐modifying efficacy to statins and cardiovascular benefit, but is underutilised because of flushing, mediated primarily by prostaglandin D2 (PGD2). Laropiprant (LRPT), a PGD2 receptor (DP1) antagonist that reduces niacin‐induced flushing has been combined with extended‐release niacin (ERN) into a fixed‐dose tablet. Methods and results: Dyslipidaemic patients were randomised to ERN/LRPT 1 g (n = 800), ERN 1 g (n = 543) or placebo (n = 270) for 4 weeks. Doses were doubled (2 tablets/day; i.e. 2 g for active treatments) for 20 weeks. ERN/LRPT 2 g produced significant changes vs. placebo in LDL‐C (?18.4%), high‐density lipoprotein cholesterol (HDL‐C; 20.0%), LDL‐C:HDL‐C (?31.2%), non‐HDL‐C (?19.8%), triglycerides (TG; ?25.8%), apolipoprotein (Apo) B (?18.8%), Apo A‐I (6.9%), total cholesterol (TC; ?8.5%), TC:HDL‐C (?23.1%) and lipoprotein(a) (?20.8%) across weeks 12–24. ERN/LRPT produced significantly less flushing than ERN during initiation (week 1) and maintenance (weeks 2–24) for all prespecified flushing end‐points (incidence, intensity and discontinuation because of flushing). Except for flushing, ERN/LRPT had a safety/tolerability profile comparable with ERN. Conclusion: Extended‐release niacin/LRPT 2 g produced significant, durable improvements in multiple lipid/lipoprotein parameters. The improved tolerability of ERN/LRPT supports a simplified 1 g→2 g dosing regimen of niacin, a therapy proven to reduce cardiovascular risk.  相似文献   
994.
AIM: To evaluate inflammatory activity in patients with Crohn’s disease (CD) using technetium-99m-hexamethylpropyleneamine oxime (99mTc-HMPAO) granulocyte scintigraphy.METHODS: Twenty patients (7 male and 13 female) with CD and five healthy volunteers were selected for 99mTc-HMPAO granulocyte scintigraphy. The Crohn’s Disease Activity Index (CDAI), blood tests and C-reactive protein (CRP) of each patient were performed 7 d before the scintigraphic images. The leukocytes were labeled according to the International Society of Radiolabeled Blood Elements (ISORBE) consensus protocol and the scintigraphic images, including single photon emission computed tomography, were obtained 30 min and 2 h after injection of the radiolabeled leukocytes.RESULTS: The labeling yield of the leukocytes with the lipophilic complex 99mTc-HMPAO was 55.0% ± 10%. Six of the 20 patients (30%) presented congruent results for the three parameters investigated (CDAI, Scintigraphic Index and CRP). On the other hand, 14 patients (70%) did not show congruent results. There was no significant correlation between the indices analyzed according to the Spearman test (P > 0.05, n = 20).CONCLUSION: The results suggest that 99mTc-HMPAO-labeled leukocyte scintigraphy could be important for determining inflammatory activity in CD even in the absence of clinical symptoms.  相似文献   
995.
Objective To investigate the iodine nourishment in women of child-beating age in high risk region of iodine deficiency disorders (IDD) in Qinghai Province. Methods According to The Notice to Launch a Reinforced Survey on IDD in High Risk Region issued by The Ministry of Public Health, 17 counties in 6 districts were selected as investigated area in Qinghai Province in 2007, using two stage cluster sampling and combining The National IDD Preliminary Surveillance Scheme, 30 women aged from 18 to 40 years were selected in each village, 1 or 2 villages in each town, 3 to 5 towns in each county, who were divided into newly wedding, pregnant, lactation and other women of child-bearing age. Iodine concentration in urine was detected by the method of As3+-Ce4+catalytic spectrophotometry. Results One thousand six hundreds and four urine iodine samples were analyzed. The median was 93.3 μg/L,52.1%(836/1604),31.8%(510/1604) and 12.4%(199/1604) was lower than 100,50 and 20 μg/L, respectively. It was 70.5%(527/747) and 43.0%(128/298) of women in Yushu and Haixi that had urinary iodine lower than 100 μg/L, respectively, while it was 50% of women in the 6 districts, to be specific, 88.3%(91/103) in Nangqian, 83.8% (62/74) in Zaduo and 70.7%(118/167) in Zhiduo Counties respectively. The median of urinary iodine in women who were not lactating and not pregnant was only 88.6 μg/L, of whom 53.9% (763/1415) lower than 100 μg/L. Conclusions The women of reproductive age in high risk region of IDD are deficient of iodine in Qinghai Province.  相似文献   
996.
Objective To investigate the iodine nourishment in women of child-beating age in high risk region of iodine deficiency disorders (IDD) in Qinghai Province. Methods According to The Notice to Launch a Reinforced Survey on IDD in High Risk Region issued by The Ministry of Public Health, 17 counties in 6 districts were selected as investigated area in Qinghai Province in 2007, using two stage cluster sampling and combining The National IDD Preliminary Surveillance Scheme, 30 women aged from 18 to 40 years were selected in each village, 1 or 2 villages in each town, 3 to 5 towns in each county, who were divided into newly wedding, pregnant, lactation and other women of child-bearing age. Iodine concentration in urine was detected by the method of As3+-Ce4+catalytic spectrophotometry. Results One thousand six hundreds and four urine iodine samples were analyzed. The median was 93.3 μg/L,52.1%(836/1604),31.8%(510/1604) and 12.4%(199/1604) was lower than 100,50 and 20 μg/L, respectively. It was 70.5%(527/747) and 43.0%(128/298) of women in Yushu and Haixi that had urinary iodine lower than 100 μg/L, respectively, while it was 50% of women in the 6 districts, to be specific, 88.3%(91/103) in Nangqian, 83.8% (62/74) in Zaduo and 70.7%(118/167) in Zhiduo Counties respectively. The median of urinary iodine in women who were not lactating and not pregnant was only 88.6 μg/L, of whom 53.9% (763/1415) lower than 100 μg/L. Conclusions The women of reproductive age in high risk region of IDD are deficient of iodine in Qinghai Province.  相似文献   
997.
Transfusion patterns in pediatric open heart surgery   总被引:3,自引:1,他引:3  
BACKGROUND: Transfusions in pediatric open heart surgery were analyzed to determine the percentage of patients transfused, the types and volumes of blood components used, and the relationships among transfusions, patient characteristics, surgeon, and surgical procedure. STUDY DESIGN and METHODS: In a 9-month period, 122 patients, aged 12 or less (median, 1 year; 31% <4 months old), underwent 126 procedures (37 routine, 60 complex, 29 repeat operations). Bypass circuit size and priming solution, target intraoperative hematocrit, heparinization, protamine reversal, and transfusion indications and doses were standardized. The number of full "adult" units of packed red cells (RBCs), units of fresh-frozen plasma (FFP), and platelet concentrates (PCs) transfused in the operating room through postoperative Day 3 were tabulated. RESULTS: RBCs, FFPs, and PCs were transfused in 98, 54, and 58 percent of cases, respectively. Twenty-two percent of components were transfused postoperatively. The average numbers of components transfused for complex procedures (3.4 RBCs, 6.1 total) and repeat operations (4.0 RBCs, 8.1 total) were greater than those for routine procedures (1.8 RBCs, 2.1 total) (p<0.01). The average total number of components transfused did not correlate with surgeon or patient age; patients <4 months old used the largest mean numbers of RBCs and total components of all types. For four procedures, preoperative crossmatch and directed-donation collection orders that would be expected to produce acceptable utilization rates and a <15-percent chance of needing additional components were determined. CONCLUSION: Blood order protocols for pediatric open heart surgery can be procedure-specific, should address the use of non-red cell components, and should cover early postoperative transfusions.  相似文献   
998.
The degree of effectiveness of mosquito nets against malaria in the Americas has remained uncertain. We carried out a case-control study of net use and mild malaria in the Amazonas state of Colombia. Two hundred ninety cases were enrolled via the Health Department services, and 977 community-based controls matched for age, sex, and place of residence. We found that a large proportion of the population (96% of controls) slept under nets. Nevertheless, we found a benefit of impregnated nets compared with no net use: adjusted odds ratio (OR) for mild malaria 0.44, 95% confidence interval (CI) 0.20-0.98. Nonimpregnated nets had a benefit that was only slightly smaller but not statistically significant (OR for mild malaria 0.54, 95% CI 0.25-1.18). Travel in the previous month had an odds ratio of 6.2 (95% CI 3.1-8.8) and a population attributable fraction of 13% compared with 11% for failure to use an impregnated net. We conclude that, in the Amazon region, promotion of mosquito net use and impregnation is justified, and that there is a need for measures to protect travelers from malaria.  相似文献   
999.
OBJECTIVE: To describe the distributions of the ambulatory blood pressure in a sample drawn from the Siberian population. METHODS: In the European Project On Genes in Hypertension (EPOGH), a random population sample of 162 persons (72 men and 90 women) was investigated in Novosibirsk, Russia. Mean age (+/-SD) was 40.6+/-15.3 years. Validated oscillometric 90207 SpaceLabs monitors were programmed to obtain ambulatory blood pressure readings at intervals of 15min from 0800h to 2200h and at 30min intervals from 2200h to 0800h. Daytime and nighttime were defined using short fixed-clock time intervals, which ranged from 1000h to 2000h and from midnight to 0600h, respectively. RESULTS: In the 162 participants, of whom 54 were hypertensive, 24-h clocktime day and clocktime night blood pressures averaged 120/73, 126/79 and 110/60mmHg, respectively. Compared with daytime values, blood pressures at the clinic were 5.7/1.1mmHg lower in 108 normotensive people, but 17.0/13.1mmHg higher in 54 hypertensive patients. In the normotensive subgroup, the 95th percentiles of the 24-h clocktime day and clocktime night blood pressures were 128/81, 136/86 and 118/72mmHg, respectively. CONCLUSION: In comparison with other population surveys, the present interim report on the EPOGH study produced consistent results with respect to the distributions of the ambulatory measurements both in normotensive subjects and in the overall study population.  相似文献   
1000.
AIM: To study the influence of treatment with HMG-CoA reductase inhibitor atorvastatin on endothelial function in patients with familial hypercholesterolemia type IIa. MATERIALS AND METHODS: Sixteen patients (5m/11w, 51-/+3 years) with familial hypercholesterolemia were studied before and after 3 months of therapy with atorvastatin 20 mg/day. EDRF release test (D.Celermajer, 1992) was used to assess flow-mediated endothelium-dependent vasodilatation (FMD) of the brachial artery in response to reactive hyperemia. Plasma nitrite/nitrate (NOx) levels were measured as an indirect index of nitric oxide (NO) production in vivo using HPLC. RESULTS: Atorvastatin treatment resulted in a 32% reduction in total serum cholesterol (CH), 41% reduction in low density lipoprotein (LDL) CH, 16% reduction in triglycerides and a 21% increase in high density lipoprotein CH. Flow mediated dilatation (FMD) was impaired at baseline (5.8-/+0.9%) and significantly improved up to 9.5-/+0.9% after 3 month atorvastatin therapy (p<0.002). Change in FMD inversely correlated with baseline FMD (r = -0.58, p<0.05). There was no significant correlation between FMD and neither total serum CH nor LDL CH levels at baseline. During atorvastatin therapy significant reduction of plasma NOx levels occurred from 53.4-/+5.1 mcmol/l at baseline (range 42.6-86.2 mcmol/l) to 35.5-/+5.1 mcmol/l (18.4-46.0 mcmol/l) after treatment (p<0.02, n=7). CONCLUSION: In patients with familial hypercholesterolemia atorvastatin produced beneficial effect on endothelial function (increase in flow-mediated dilatation, decrease in NOx).  相似文献   
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