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991.
? Three indoor environments, two residential and one institutional, were monitored for particulate and gaseous air pollutants over a one-year period. Inside air particulate levels decreased at night and under conditions of no household activity. Different homes showed different time lags in correlating inside vs outside particle counts. Indoor particle count reduction correlated to rate of air flow through the precipitator. The standard, portable household vacuum cleaner produced about a 100% increase in counts of particles measuring 1.0μm and larger, as compared to a 50% increase produced by the central vacuum system. Particulates that were smaller than 1.0μm were not substantially affected by household activity, but they were affected by smoking. The indoor gaseous pollutants showed very low maximum levels.  相似文献   
992.
PURPOSE: The tumor-associated auto-antigen p53 is commonly overexpressed in various types of human cancer, including colorectal cancer. Experiments in preclinical models have shown that it can serve as a target for T-cell-mediated tumor-eradication. The feasibility of a p53-specific therapeutic vaccination was investigated in cancer patients. EXPERIMENTAL DESIGN: A Phase I/II dose-escalation study was performed that evaluated the effect of a recombinant canarypoxvirus (ALVAC) vaccine encoding wild-type human p53 in 15 patients with advanced colorectal cancer. Each group of five patients received three i.v. doses of one-tenth of a dose, one-third of a dose, or 1 dose of the vaccine [1 dose = 1 x 10(7.5) cell culture infectious dosis (CCID)50]. RESULTS: Potent T-cell and IgG antibody responses against the vector component of the ALVAC vaccine were induced in the majority of the patients. Enzyme-linked immunosorbent-spot assay (ELISPOT) analysis of vaccine-induced immunity revealed the presence of IFN-gamma-secreting T cells against both ALVAC and p53, whereas no significant interleukin-4 responses were detected. Vaccine-mediated enhancement of p53-specific T-cell immunity was found in two patients in the highest-vaccine-dose group. CONCLUSIONS: This study demonstrated the feasibility, even in patients with advanced cancer, to elicit immune responses against the ubiquitously expressed tumor-associated auto-antigen p53. Our results form the basis for additional studies that will explore the antitumor capacity of p53 containing multivalent vaccines in cancer patients with limited tumor burden.  相似文献   
993.
Although known, histologically proven pulmonary metastasis from a benign intracranial meningioma is exceedingly rare. We report a case of meningiothelial meningioma producing a solitary pulmonary deposit.  相似文献   
994.
Human infectiousness to mosquitoes can be estimated by 2 tests: direct feeding on the skin and membrane feeding on venous blood. To validate the membrane feeding assay, the infectiousness of Plasmodium falciparum gametocyte carriers to Anopheles gambiae was estimated by these 2 methods in the same individuals in a rural area of Cameroon. Results from 37 experiments showed that direct feeding gave significantly higher infection rates than membrane feeding. We observed an average of 19.4% infected mosquitoes by direct feeding compared with 12.1% by membrane feeding, and a mean oocyst load of 5.63 by direct feeding compared with 2.65 by membrane feeding. However, there was a very good concordance between the 2 tests: 84.3% with the Kappa test on percentages of infected mosquitoes and 98.7% with the interclass correlation coefficient on oocyst loads. In addition, we found a good linear correlation between the 2 methods.  相似文献   
995.
Problems of ileostomy in necrotizing enterocolitis   总被引:2,自引:0,他引:2  
Exteriorization of the intestine and resection of the gangrenous bowel are major therapeutic regimens for necrotizing enterocolitis (NEC). Ileostomy associated complications are well known, therefore the time of ileostomy closure is a matter for discussion. Between 1975 and 1992, 84 patients with NEC were treated surgically. Ileostomies were performed in 37 children (44%). Of these 37 neonates, 9 (7M, 2F) died. In the remaining 28 patients (16M, 12F) with a mean gestational age of 35.8 weeks and a mean birth weight of 2412 g, ileostomies were performed between the 2nd and 11th days after birth. On average, the stomies were in function for 91 days, and within this period the average weekly weight gain was 153 g. Nineteen patients of this group did not show any problems attributable to the ileostomy. In 9 patients (32%) complications occurred, requiring a preplanned closure of the stoma. Postinflammatory strictures of bowel were diagnosed in 9 patients and resection of the stenotic intestine was performed at the same time as stoma closure. In conclusion, an appropriate weight gain can be achieved in patients with an ileostomy with an adequate feeding regimen. In otherwise uncomplicated cases, ileostomy closure can be delayed by up to 10 weeks when simultaneous surgical correction of additional intestinal strictures is possible. In one-third of patients with an ileostomy, however, complications may occur and urge a preplanned closure of the stoma.  相似文献   
996.
A novel form of severe, X linked mental retardation associated with alpha thalassaemia (ATR-X syndrome) has recently been described. Two affected cousins are described, one of whom has an unusually mild haematological phenotype. HbH inclusions, which are the hallmark of this disease, were only detected in the peripheral red blood cells after repeated observations.  相似文献   
997.
The sweat test was performed by the method of Gibson and Cooke on 36 children with second and third degree malnutrition, aged from 2 months to 4 years. The results were compared with those from 32 healthy, well nourished controls in the same age range. Determinations were made of sodium and chloride concentrations, chloride/sodium ratio, and the sum of the concentrations of the two electrolytes in each sample. The malnourished children were found to have higher sodium and chloride concentrations than the well nourished ones. None of the normal or malnourished children had a sweat chloride value greater than 60 mmol/l; chloride values within a suspicious range (between 40 and 60 mmol/l) were found in two malnourished children. Two well nourished controls and six malnourished children showed suspicious sweat sodium concentrations; in one child with third degree malnutrition the sodium content was greater than 60 mmol/l. In all results in the suspicious range, or greater than 60 mmol/l, the chloride/sodium ratio was less than 1, and the sum of the two electrolytes was below 140 mmol/l. Based on these results, we conclude that malnourished children have raised sweat sodium and chloride concentrations when compared with well nourished children. The electrolyte values for most of them are not in a suspicious range or consistent with a diagnosis of cystic fibrosis. Unlike that found in cystic fibrosis, the sodium/chloride ratio in our subjects was less than 1 and the sum of both electrolytes never exceeded 140 mmol/l.  相似文献   
998.
999.
Background: Patients with essential hypertension show altered baroreflex control of heart rate, and during the perioperative period they demonstrate increased circulatory instability. Clonidine has been shown to reduce perioperative circulatory instability. This study documents changes in measures of heart rate control after surgery in patients with essential hypertension and determines the effects of clonidine on postoperative heart rate control in these patients.

Methods: Using a randomized double-blind placebo-controlled design, 20 patients with essential hypertension (systolic pressure > 160 mmHg or diastolic pressure > 95 mmHg for >or= to 1 yr) were assigned to receive clonidine (or placebo), 6 [micro sign]g/kg orally 120 min before anesthesia and 3 [micro sign]g/kg intravenously over 60 min before the end of surgery. The spontaneous baroreflex ("sequence") technique and analysis of heart rate variability were used to quantify control of heart rate at baseline, before induction of anesthesia, and 1 and 3 h postoperatively.

Results: Baroreflex slope and heart rate variability were reduced postoperatively in patients given placebo but not those given clonidine. Clonidine resulted in greater postoperative baroreflex slope and power at all frequency ranges compared with placebo (4.9 +/- 2.9 vs. 2.2 +/- 2.1 ms/mmHg for baroreflex slope, 354 +/- 685 vs. 30 +/- 37 ms2/Hz for high frequency variability). Clonidine also resulted in lower concentrations of catecholamine, decreased mean heart rate and blood pressure, and decreased perioperative tachycardia and hypertension.  相似文献   

1000.
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