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71.
Brazil was considered one of the emerging epicenters of the coronavirus pandemic in 2021, experiencing over 3000 daily deaths caused by the virus at the peak of the second wave. In total, the country had more than 20.8 million confirmed cases of COVID-19, including over 582,764 fatalities. A set of emerging variants arose in the country, some of them posing new challenges for COVID-19 control. The goal of this study was to describe mutational events across samples from Brazilian SARS-CoV-2 sequences publicly obtainable on Global Initiative on Sharing Avian Influenza Data-EpiCoV (GISAID-EpiCoV) platform and to generate indexes of new mutations by each genome. A total of 16,953 SARS-CoV-2 genomes were obtained, which were not proportionally representative of the five Brazilian geographical regions. A comparative sequence analysis was conducted to identify common mutations located at 42 positions of the genome (38 were in coding regions, whereas two were in 5′ and two in 3′ UTR). Moreover, 11 were synonymous variants, 27 were missense variants, and more than 44.4% were located in the spike gene. Across the total of single nucleotide variations (SNVs) identified, 32 were found in genomes obtained from all five Brazilian regions. While a high genomic diversity has been reported in Europe given the large number of sequenced genomes, Africa has demonstrated high potential for new variants. In South America, Brazil, and Chile, rates have been similar to those found in South Africa and India, providing enough “space” for new mutations to arise. Genomic surveillance is the central key to identifying the emerging variants of SARS-CoV-2 in Brazil and has shown that the country is one of the “hotspots” in the generation of new variants.  相似文献   
72.
Prenatal ultrasound diagnosis of clubfoot   总被引:1,自引:0,他引:1  
Benacerraf  BR; Frigoletto  FD 《Radiology》1985,155(1):211-213
Five cases of congenital clubfoot diagnosed prenatally by ultrasound are reported. The incidence of clubfoot may be higher within an affected family and may be associated with other structural anomalies or chromosomal abnormalities. Identifying a clubfoot in utero should therefore alert the sonographer that other anomalies may be present and should lead to a detailed structural survey.  相似文献   
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The clinical profile, malignant potential, and management of 17 children with juvenile polyposis (more than five juvenile polyps) were evaluated clinically and endoscopically. Colonoscopy and polypectomy were done three weekly until colonic clearance was achieved, and thereafter two yearly. All polyps were subjected to histological examination. Mean age was 7.7 years, with a male preponderance (3:1). Presentation was with rectal bleeding (94%), pallor (65%), stunted growth (53%), and oedema (47%), and the mean (SD) duration of symptoms was 33 (27) months. None had a positive family history or any congenital anomaly. Two children had six polyps up to the transverse colon; the rest had numerous polyps all over the colon. All children had juvenile polyps on histology and 10 (59%) had adenomatous changes (dysplasia). Total colectomy was done in six for intractable symptoms. Colon clearance was achieved in eight after an average 3.4 polypectomy sessions, and three were still on the polypectomy programme. In conclusion, juvenile polyposis is commonly associated with low grade dysplasia. Serial colonoscopic polypectomy is effective but colectomy is required for intractable symptoms and when clearance of the colon is not possible.  相似文献   
77.
Radiocontrast-induced nephropathy (RCIN) is a common cause of hospital-acquired acute renal failure and is associated with a high mortality rate. RCIN is potentially preventable, because administration of the radiocontrast agent is predictable, and a high-risk population has been identified. This multicenter, prospective, randomized, double-blind, placebo-controlled trial was performed to evaluate the efficacy of intravenous atrial natriuretic peptide (anaritide, ANP 4-28) to prevent RCIN. Patients with stable chronic renal failure (serum creatinine greater than 1.8 mg/dL or serum creatinine between 1.5 and 1.8 mg/dL with estimated creatinine clearance of < or = 65 mL/min) were assigned to receive either placebo or one of three doses of anaritide (0.01 microg/kg/min, 0.05 microg/kg/min, or 0.1 microg/kg/min) for 30 minutes before and continuing for 30 minutes after radiocontrast administration. All patients were given intravenous 0.45% saline for 12 hours before the radiocontrast procedure and continuing for 12 hours after the last dose of radiocontrast. Both ionic and nonionic radiocontrast agents were administered. RCIN was defined as either an absolute increase of serum creatinine of > or = 0.5 mg/dL or a percent increase of > or = 25% over baseline. Of the 247 patients who completed the study, 50% had diabetes mellitus. There were no statistical differences in baseline serum creatinine, change in serum creatinine, or the incidence of RCIN. The incidence of RCIN was placebo, 19%; anaritide (0.01), 23%; anaritide (0.05), 23%; anaritide (0.1), 25%. Patients with diabetes mellitus had a significantly greater incidence of RCIN: placebo, 26% versus 9%; anaritide (0.01), 33% versus 13%; anaritide (0.05), 26% versus 21%; anaritide (0.1), 39% versus 8% (diabetic v nondiabetic, P < 0.002). There was no effect in the diabetic or nondiabetic groups by anaritide on the incidence of RCIN. Comparison of the highest-risk group of patients, defined as patients with diabetes mellitus and a baseline serum creatinine > or = 1.8 mg/dL, with the lowest-risk group, defined as patients without diabetes mellitus and a baseline serum creatinine of 1.8 mg/dL or less, did not show a beneficial effect of anaritide administration. In conclusion, administration of intravenous anaritide before and during a radiocontrast study did not reduce the incidence of RCIN in patients with preexisting chronic renal failure, with or without diabetes mellitus.  相似文献   
78.
Background. Ankle-brachial index (ABI) is an excellent methodfor the diagnosis of peripheral arterial disease (PAD) whenit is performed with Doppler. However, this device is not alwaysavailable for primary care physicians. The ABI measured withstethoscope is an easy alternative approach, but have not beenproved to be useful. Objective. To assess the accuracy of the ABI measured usinga stethoscope comparatively to that of the current eligiblemethod for the diagnosis of PAD, the Doppler ABI, and describethe characteristics of this new approach. Methods. We conducted a diagnostic study of ABI measured witha stethoscope and a Doppler probe and compared the results.Eighty-eight patients were accessed by both methods. Results. Mean stethoscope ABI, 1.01 ± 0.15, and meanDoppler ABI, 1.03 ± 0.20, (P = 0.047) displayed a goodcorrelation. Measurements of stethoscope ABI diagnostic accuracyin recognizing a Doppler ABI are described. The comparison ofthis data with the current gold standard method results gavea sensitivity of 71.4% [95% confidence interval (CI), 41.9–91.6]and specificity of 91.0% (95% CI, 81.5–96.6), with predictivepositive value of 62.5% (95% CI, 38.6–81.5) and negativepredictive value of 93.8% (95% CI, 85.2–97.6). The studyaccuracy was 87.7%. The area under the ROC curve was 0.895 (95%CI, 0.804–0.986, P < 0.0001). Conclusions. According to our study, the stethoscope ABI isa useful method to detect PAD and it may be suitable for itsscreening in the primary care setting. Keywords. Ankle-brachial index, peripheral arterial disease, stethoscope.  相似文献   
79.
本文依据一组含有不同比例待测和干扰组分的标准混合液的吸收值,采用一元线性回归方法,在选择最佳测定波长对的同时建立标准工作曲线方程,使其更符合实际作品测定时的情况,提高了结果的精度和可靠性,并使计算量和实验工作量得以降低。应用于复方氨基比林注射液中三组分氨基比林、安替比林和巴比妥的同时测定,其平均回收率分别为99.8%,100.4%和99.8%,变异系数分别为0.59,1.48和1.05,结果优于卡尔曼滤波法、偏最小二乘法和目标因子分析法。  相似文献   
80.
ERNST J., WEISSFLOG, G., BRÄHLER E., NIEDERWIESER D., KÖRNER A. & SCHRÖDER C. (2010) European Journal of Cancer Care
Participation of haemato‐oncological patients in medical decision making and their confidence in decisions Increasingly more clinical care and research acknowledge the patients' interest in participating in medical decision making. However, for haematological patients, there are as yet only modest findings. The current study explores patients' perceptions of their role in the medical decision‐making process in a sample of 117 haematological patients. The majority of patients surveyed (63.9%) took a passive role in the medical decision‐making process, which is a significantly greater proportion compared with individuals suffering from solid cancers. Despite passive majority, most of the participants reported a positive evaluation of the decision‐making process. Importantly, patients' evaluations were significantly more negative either if patients were treated as inpatients (vs. outpatients), or if they experienced no control over the decision (vs. collaboration with the doctor, or deciding autonomously). The results and limitations of the study are discussed.  相似文献   
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