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Results of contrast material-enhanced computed tomography (CT) and T2-weighted spin-echo magnetic resonance (MR) imaging were correlated with pathologic findings in 25 patients treated surgically for refractory partial epilepsy. Of 12 lesions present, ten (83%) were detected by MR imaging and seven (58%) by CT scanning. Of nine low-grade gliomas, eight were detected by MR imaging and four by CT scanning. One posttraumatic scar and one case of temporal lobe atrophy were better demonstrated by MR imaging. A small, thrombosed arteriovenous malformation was the only lesion detected by CT scanning but not by MR imaging. No lesions were detected in 13 patients with mild gliosis and one patient with a 1.2-cm grade 1 astrocytoma. Although more sensitive than CT for detection of structural lesions in patients with refractory partial epilepsy, MR imaging resulted in a 25% false-negative diagnostic rate when a repetition time of 2,000 msec and echo time of 60 msec were used. Multi-echo imaging with at least one long echo time may be needed to increase the sensitivity of MR imaging in these patients.  相似文献   
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It has been reported that lanosterol can sensitize isolated rat platelets to agonists such as ADP and thrombin (4). The purpose of this paper was to determine whether lanosterol had similar effects on human platelets and whether this was achieved by changes in membrane fluidity. Lanosterol did increase the sensitivity of human platelets, particularly to adrenaline and ADP at concentrations as low as 5 mg.L-1 when added from solutions in ethanol. At similar concentrations cholesterol, 4-cholesten-3-one or ethynyloestradiol had either no effect or were inhibitory. Measurement of membrane fluidity with diphenylhexatriene indicated that lanosterol did not affect membrane fluidity. Incubation of platelets with [4C]-mevalonic acid gave rise to a very small incorporation into lanosterol, squalene and farnesol. Sudden activation of the platelets did not accelerate lanosterol synthesis during or after platelet aggregation. It was concluded that lanosterol could only influence platelet behaviour if it came from the plasma. However the concentration of the steroid in both platelets and plasma is ten fold less than that required to sensitise the platelets.  相似文献   
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The association between dummy use and sudden infant death syndrome (SIDS) was investigated in 485 deaths due to SIDS in the postneonatal age group and compared with 1800 control infants. Parental interviews were completed in 87% of subjects. The prevalence of dummy use in New Zealand is low and varies within New Zealand. Dummy use in the two week period before death was less in cases of SIDS than in the last two weeks for controls (odds ratio (OR) 0.76, 95% confidence interval (CI) 0.57 to 1.02). Use of a dummy in the last sleep for cases of SIDS or in the nominated sleep for controls was significantly less in cases than controls (OR 0.44, 95% CI 0.26 to 0.73). The OR changed very little after controlling for a wide range of potential confounders. It is concluded that dummy use may protect against SIDS, but this observation needs to be repeated before dummies can be recommended for this purpose. If dummy sucking is protective then it is one of several factors that may explain the higher mortality from SIDS in New Zealand than in other countries, and may also explain in part the regional variation within New Zealand.  相似文献   
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Milner G  Hassall C 《Health trends》1990,22(4):141-145
The Worcester Development Project began in 1968 when the Department of Health and Social Security brought together the Worcester and Kidderminster Hospital Management Committee and the County Council in a co-ordinated joint planning venture. Powick Hospital was chosen as the location for testing the hypothesis that closing a mental hospital and replacing it with general hospital psychiatric units, supported by a variety of community facilities, would provide a more economical and better service. This paper describes the outcome of this unique opportunity to study the problems involved in closing a mental hospital and its replacement with other facilities.  相似文献   
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Background

The purpose of this study was to evaluate amifostine for protection from cisplatin-induced serious hearing loss in patients with average-risk medulloblastoma by extending a previous analysis to a much larger sample size. In addition, this study aimed to assess amifostine with serious hearing loss in patients with high-risk medulloblastoma treated with cisplatin.

Methods

Newly diagnosed medulloblastoma patients (n = 379; ages 3–21 years), enrolled on one of 2 sequential St. Jude clinical protocols that included 4 courses of 75 mg/m2 cisplatin, were compared for hearing loss by whether or not they received 600 mg/m2 of amifostine immediately before and 3 hours into each cisplatin infusion. Amifostine administration was not randomized. The last audiological evaluation between 5.5 and 24.5 months following protocol treatment initiation was graded using the Chang Ototoxicity Scale. A grade of ≥2b (loss requiring a hearing aid or deafness) was considered a serious event.

Results

Among average-risk patients (n = 263), amifostine was associated with protection from serious hearing loss (adjusted OR, 0.30; 95% CI, 0.14–0.64). For high-risk patients (n = 116), however, there was not sufficient evidence to conclude that amifostine prevented serious hearing loss (OR, 0.89; 95% CI, 0.31–2.54).

Conclusions

Although patients in this study were not randomly assigned to amifostine treatment, we found evidence in favor of amifostine administration for protection against cisplatin-induced serious hearing loss in average-risk but not in high-risk, medulloblastoma patients.  相似文献   
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OBJECTIVES: To assess the severity and causes of inflammation of the gastric cardia in children undergoing endoscopy for symptoms of acid peptic disease. STUDY DESIGN: Patients undergoing upper gastrointestinal endoscopy for symptoms of acid peptic disease had biopsies from gastric cardia, gastric, and esophageal sites, and 24-hour intraesophageal pH monitoring. Gastric cardia was defined at endoscopy as the anatomic zone from the squamocolumnar junction to 0.5 cm below it. Severity of gastric cardia inflammation was scored 0 to 9 according to densities of inflammatory cells and epithelial abnormalities in surface and pit epithelium. A score > or =2 was considered positive. RESULTS: Forty-seven children (median age, 6.5 years; range, 3-15) had Helicobacter pylori infection, gastroesophageal reflux disease (GERD), or both. In 22 patients, H pylori was detected in cardiac biopsies by rapid urease test and histology; it was detected also in the corpus and antrum in only seven of the 22. No patient had H pylori in gastric corpus/antrum without having the organism at the cardia as well. In 12 H pylori-positive patients, GERD was also diagnosed. Twenty-five patients had GERD and no H. pylori infection. Severity score was 3.8+/-0.8 in the H pylori group and 2.08+/-0.9 in the GERD alone group (P<.001); however, there was no difference in reflux index (24-hour % of gastroesophageal reflux) between the two groups. In neither group was correlation found between reflux index and severity score (H pylori, r=0.22; GERD alone, r=0.31; NS) nor between cardia inflammation and esophagitis grade (H pylori, r=0.37; GERD alone, r=0.22; NS). CONCLUSIONS: In children with symptoms of acid peptic disease, inflammation of the gastric cardia does occur. It is more severe when the cardiac zone is infected with H pylori than in its absence. Of major practical significance is the finding that the gastric cardia is a highly sensitive site for the detection of H pylori infection.  相似文献   
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