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《Clinical oncology (Royal College of Radiologists (Great Britain))》2020,32(7):467-476
AimsMore efforts are required to minimise late radiation side-effects for paediatric patients. Pencil beam scanning proton beam therapy (PBS-PT) allows increased sparing of normal tissues while maintaining conformality, but is prone to dose degradation from interplay effects due to respiratory motion. We report our clinical experience of motion mitigation with volumetric rescanning (vRSC) and outcomes of children with neuroblastoma.Materials and methodsNineteen patients with high-risk (n = 16) and intermediate-risk (n = 3) neuroblastoma received PBS-PT. The median age at PBS-PT was 3.5 years (range 1.2–8.6) and the median PBS-PT dose was 21 Gy (relative biological effectiveness). Most children (89%) were treated under general anaesthesia. Seven patients (37%) underwent four-dimensional computed tomography for motion assessment and were treated with vRSC for motion mitigation.ResultsThe mean result of maximum organ motion was 2.7 mm (cranial–caudal), 1.2 mm (left–right), 1.0 mm (anterior–posterior). Four anaesthetised children (21%) showing <5 mm motion had four-dimensional dose calculations (4DDC) to guide the number of vRSC. The mean deterioration or improvement to the planning target volume covered by 95% of the prescribed dose compared with static three-dimensional plans were: 4DDC no vRSC, –0.6%; 2 vRSC, +0.3%; 4 vRSC, +0.3%; and 8 vRSC, +0.1%. With a median follow-up of 14.9 months (range 2.7–49.0) there were no local recurrences. The 2-year overall survival was 94% and distant progression-free survival was 76%. Acute grade 2–4 toxicity was 11%. During the limited follow-up time, no late toxicities were observed.ConclusionsThe early outcomes of mainly high-risk patients with neuroblastoma treated with PBS-PT were excellent. With a subset of our cohort undergoing PBS-PT with vRSC we have shown that it is logistically feasible and safe. The clinical relevance of vRSC is debatable in anaesthetised children with small pre-PBS-PT motion of <5 mm. 相似文献
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Rohini KhuranaSatyajeet RathHarikesh Bahadur SinghMadhup RastogiSambit Swarup NandaAbhishek ChauhanMohammad KaifNuzhat Hussain 《Asian Pacific journal of cancer prevention》2020,21(3):755-760
Background: The standard of care in high grade glioma (HGG) is maximal safe surgical resection followed by adjuvant radiotherapy (RT) with/without chemotherapy. For anaplastic gliomas, studies have shown use of procarbazine, lomustine, vincristine (PCV) improves overall survival (OS) and progression free survival (PFS). Currently, there is substantial evidence that molecular markers strongly predict prognosis and response to treatment. Methods: Between January 2016 to January 2018, 42 patients were accrued and followed up till April 2019. The primary end points were to correlate molecular markers with response to therapy in terms of OS and PFS in HGG. The secondary end point was to evaluate frequency of 1p/19q codeletion, IDH 1 mutation, ATRX deletion and p53 in HGG patients. Results: The median age was 46 years (range 18-67) with M:F ratio 30:12. The frequency of IDH1 mutation,1p/19q codeletion, p53 mutation and ATRX mutation were 42.8%, 16.6%, 42.8% and 14.2% respectively. All the seven patients with 1p/19q codeletion had IDH1 mutation. Median follow up was 22 months. The 20-months PFS for different mutations were as follows; IDH1-mutated vs wild type: 53.6% vs 29.8%; p-0.035, 1p/19q codeleted vs non-codeleted: 85.7% vs 62.3%; p-0.011, p53 wild type vs mutated 32.1% vs 35.6%; p-0.035 and ATRX lost vs retained: 55.6% vs 53.3%; p- 0.369. The 20-months OS for IDH1 mutated vs wild type: 82.4% vs 30.6%; p-0.014, 1p/19q codeleted vs non-codeleted: 85.7% vs 65.8%; p-0.104, p53 wild-type vs mutated 45.5% vs 73.9%; p-0.036 and ATRX lost vs retained: 100% vs 60.3%; p-0.087. Conclusion: Codeletion of 1p/19q with IDH1 mutation in HGG is associated with a significantly favourable PFS. However, larger studies with longer follow up are required to evaluate OS and PFS in all the molecular subgroups. 相似文献
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目的探讨先天性肾性尿崩症的临床特点、基因诊断及治疗。方法回顾分析2例先天性肾性尿崩症患儿的临床资料。结果 2例男性患儿分别为5岁和3岁2个月,均以多饮多尿、生长迟缓为主要表现。经禁水-加压素试验证实为持续低比重尿。尿崩症相关基因检测发现,例1患儿精氨酸加压素受体2(AVPR2)基因外显子2杂合错义突变c.650CT(p.P217L),且为新发变异。例2患儿AVPR2基因外显子1及外显子2缺失,亦为新发变异,其母亲为携带者,父亲AVPR2基因未见异常变异。对新发的变异位点通过Mutation-taster及Polyphen2软件预测为致病性变异。2例患儿口服氢氯噻嗪联合吲哚美辛治疗1年,尿量及夜尿减少,无电解质紊乱及肾功能受损等。结论 AVPR2基因为先天性肾性尿崩症的主要致病基因,发现2种国内外未见报道的新变异位点。 相似文献
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目的探讨Alport综合征的临床特点及其相关致病基因。方法回顾分析1个Alport综合征家系的临床资料。结果先证者,男,11岁8个月,COL4A5基因中鉴定出TTCT插入突变(c.41_42 dup TCTT),该插入突变引起了移码突变。使用Integrative Genomics Viewer软件进行分析,该移码突变导致自之后的第13个氨基酸残基发生改变,且在第40个氨基酸残基处出现终止密码子,导致蛋白表达提前终止。患儿母亲和外祖母均携带该变异,分别在35岁和34岁时达到终末期肾病,且都有听力受损,但未发现眼部异常。家系分析表明该变异与该家系患病成员存在共分离关联。结论基因检测有助于Alport综合征确诊,该家系扩展了Alport综合征的致病变异谱。 相似文献
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《Brain stimulation》2020,13(5):1284-1295
BackgroundElectroconvulsive therapy (ECT) technique is often changed after insufficient improvement, yet there has been little research on switching strategies.ObjectiveTo document clinical outcome in ECT nonresponders who were received a second course using high dose, brief pulse, bifrontotemporal (HD BP BL) ECT, and compare relapse rates and cognitive effects relative to patients who received only one ECT course and as a function of the type of ECT first received.MethodsPatients were classified as receiving Weak, Strong, or HD BP BL ECT during three randomized trials at Columbia University. Nonresponders received HD BP BL ECT. In a separate multi-site trial, Optimization of ECT, patients were randomized to right unilateral or BL ECT and nonresponders also received further treatment with HD BP BL ECT.ResultsRemission rates with a second course of HD BP BL ECT were high in ECT nonresponders, approximately 60% and 40% in the Columbia University and Optimization of ECT studies, respectively. Clinical outcome was independent of the type of ECT first received. A second course with HD BP BL ECT resulted in greater retrograde amnesia immediately, two months, and six months following ECT.ConclusionsIn the largest samples of ECT nonresponders studied to date, a second course of ECT had marked antidepressant effects. Since the therapeutic effects were independent of the technique first administered, it is possible that many patients may benefit simply from longer courses of ECT. Randomized trials are needed to determine whether, when, and how to change treatment technique in ECT. 相似文献
60.
Analysis of Heterozygous BRCA1 5382ins Founder Mutation in a Cohort of Egyptian Breast Cancer Female Patients Using Pyrosequencing Technique 下载免费PDF全文
Salwa H Gomaa MogahedYasser S HamedYassmin E Ibrahim MoursyMarwa H Mahomoud Saied 《Asian Pacific journal of cancer prevention》2020,21(2):431-438
Background: Up to half of the heritable mutations in breast cancer (BC) are attributed to BRCA1 and BRCA2 genes. The mutation prevalence is variable based on ethnicity and may be influenced by founder mutations. The aim of this pilot study is to determine for the first time, the prevalence of BRCA1 5382insC founder mutation in a cohort of Egyptian familial breast cancer patients (FBC). Methods: Female patients were selected to have familial type of breast cancer. Twenty healthy females were included as a control group. Peripheral blood samples were withdrawn from all studied females and were analyzed for BRCA1 5382insC founder mutation detection using pyrosequencing technique. Results: Eighty Egyptian FBC females were eligible to be enrolled in the study with a mean age of 48.31 ± 10.97years.We found a BRCA1 5382insC mutation carrier frequency of 5% of total studied FBC patients (4 out of 80 patients) with 95% confidence interval (1.61-12.99). There was a high statistical significant difference between carriers and non-carriers concerning the number of affected family members by BC, (p=0.001). Conclusion: BRCA1 5382insC founder mutation is not uncommon among Egyptian FBC females. The carrier frequency is comparable to that reported worldwide; however it is lower than those from previous Egyptian studies using different molecular techniques. The strong association between the mutation and the number of affected family members suggest wider screening of the mutation among high risk families using the reliable pyrosequencing technique. 相似文献