全文获取类型
收费全文 | 33693篇 |
免费 | 2406篇 |
国内免费 | 885篇 |
专业分类
耳鼻咽喉 | 613篇 |
儿科学 | 441篇 |
妇产科学 | 501篇 |
基础医学 | 5362篇 |
口腔科学 | 581篇 |
临床医学 | 3254篇 |
内科学 | 6151篇 |
皮肤病学 | 1248篇 |
神经病学 | 2302篇 |
特种医学 | 1954篇 |
外国民族医学 | 2篇 |
外科学 | 4077篇 |
综合类 | 1467篇 |
现状与发展 | 2篇 |
一般理论 | 9篇 |
预防医学 | 1567篇 |
眼科学 | 677篇 |
药学 | 3388篇 |
2篇 | |
中国医学 | 797篇 |
肿瘤学 | 2589篇 |
出版年
2024年 | 37篇 |
2023年 | 348篇 |
2022年 | 1031篇 |
2021年 | 1532篇 |
2020年 | 843篇 |
2019年 | 1072篇 |
2018年 | 1214篇 |
2017年 | 1019篇 |
2016年 | 1356篇 |
2015年 | 1944篇 |
2014年 | 2221篇 |
2013年 | 2331篇 |
2012年 | 3337篇 |
2011年 | 3210篇 |
2010年 | 1992篇 |
2009年 | 1608篇 |
2008年 | 2079篇 |
2007年 | 1861篇 |
2006年 | 1642篇 |
2005年 | 1351篇 |
2004年 | 1024篇 |
2003年 | 972篇 |
2002年 | 785篇 |
2001年 | 419篇 |
2000年 | 331篇 |
1999年 | 316篇 |
1998年 | 192篇 |
1997年 | 138篇 |
1996年 | 89篇 |
1995年 | 66篇 |
1994年 | 57篇 |
1993年 | 64篇 |
1992年 | 78篇 |
1991年 | 76篇 |
1990年 | 38篇 |
1989年 | 48篇 |
1988年 | 34篇 |
1987年 | 28篇 |
1986年 | 24篇 |
1985年 | 27篇 |
1984年 | 21篇 |
1983年 | 7篇 |
1982年 | 10篇 |
1981年 | 17篇 |
1979年 | 9篇 |
1978年 | 7篇 |
1977年 | 11篇 |
1976年 | 7篇 |
1974年 | 8篇 |
1969年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 43 毫秒
61.
Byong Kak Kim Eung Chil Choi Kyeong Soo Chung Hee Ju Park Hye Ryoung Kim Yang Sup Kim Yong Hwan Park Mi Ja Shim 《Archives of pharmacal research》1983,6(2):141-142
To find antitumor metabolites in Korean basidiomycetes, the shake-cultured mycelia of eight of the higher fungi were extracted with hot water and the extracts, after being partially purified, were subjected toin vivo antitumor test. When administeredi.p. at the dose of 30mg/kg/day for ten consecutive days into the female ICR mice, which had been implanted with 1×105 cells of sarcoma 180 twenty-four hours before the first injection, the extracts ofAgaricus campestris, Lyophyllum decastes, Lyophyllum ulmarium, Armillaria tabescence andCalvatia exipulitormis respectively showed inhibition ratios of 64.1%, 65.4%, 60.0%, 53.0% and 49.3%. These five species were selected for further study, whereas the extracts ofPhallus impudicus, Coprinus comatus andPholiota squarrosa which showed the inhibition ratios of 31.2%, 33.5% and 19.0% were discontinued. 相似文献
62.
Selective neuronal survival and upregulation of PCNA in the rat inner retina following transient ischemia 总被引:1,自引:0,他引:1
Ju WK Kim KY Hofmann HD Kim IB Lee MY Oh SJ Chun MH 《Journal of neuropathology and experimental neurology》2000,59(3):241-250
In this study we investigated the extent and time course of neuronal cell death and the regulation of the proliferating cell nuclear antigen (PCNA) in the different retinal cell layers following ischemia-reperfusion injury. Retinal ischemia was induced by controlled elevation of the intraocular pressure for a duration of 60 min. Changes in thickness and cell numbers in the retinal cell layers were analyzed at various time points (1 h to 4 weeks) after reperfusion. In parallel, apoptotic cell death was determined by the TUNEL method and the expression of PCNA analyzed by immunocytochemistry. In addition, we tested whether PCNA is expressed in neurons by double immunocytochemistry. The reduction in thickness was found to be less pronounced in the inner nuclear layer (INL). Correspondingly, cell numbers decreased by only 33% in the inner retina, but by more than 80% in the outer nuclear layer (ONL). Alterations in glial cell numbers did not contribute significantly to postischemic changes in the INL and ONL as assessed by using immunocytochemical markers for microglial and Müller cells. The time course of cell death determined by the TUNEL technique also differed markedly in the retinal layers being rapid and transient in the inner retina but delayed and prolonged in the ONL. PCNA immunoreactivity was undetectable in the normal retina, but was specifically induced in neurons of the inner retina within 1 h after reperfusion and was sustained for at least 4 weeks. We conclude that in contrast to photoreceptors in the ONL, a significant proportion of inner retinal neurons is resistant to ischemic insult induced by transiently increased intraocular pressure and that PCNA may possibly play a role in the selective postischemic survival of these cells. 相似文献
63.
Objectives: To characterize whether adult depressives with either bipolar or unipolar disorder differ in the prevalence of childhood sexual or physical abuse.
Method: The investigators reviewed data from patients who were evaluated over a 2-year period by a semi-structured clinical interview. In total, 333 cases with a bipolar or unipolar diagnosis were included in the present study.
Results: A childhood history of abuse, in particular sexual abuse, was significantly more frequent in bipolar subjects compared with unipolar subjects. Consistent with previous studies, women reported higher rates of sexual abuse than men, although no interaction by diagnosis was shown. Sexual abuse incidence in male samples was markedly dissimilar, with male bipolar subjects demonstrating a significantly increased rate of sexual abuse and combined sexual and physical abuse compared with unipolar male subjects.
Conclusion: The increased incidence of sexual abuse in women supports growing evidence of gender differences in sexual abuse among adult depressives. In contrast to literature reports, the finding that male bipolar patients have significantly increased rates of sexual abuse histories suggests differences in psychiatric depressive subgroups. This result may reflect the particular characteristics of our cohort (treatment resistant, privately insured, and educated). Further work will aid in characterizing sexual abuse prevalence in other male bipolar samples. 相似文献
Method: The investigators reviewed data from patients who were evaluated over a 2-year period by a semi-structured clinical interview. In total, 333 cases with a bipolar or unipolar diagnosis were included in the present study.
Results: A childhood history of abuse, in particular sexual abuse, was significantly more frequent in bipolar subjects compared with unipolar subjects. Consistent with previous studies, women reported higher rates of sexual abuse than men, although no interaction by diagnosis was shown. Sexual abuse incidence in male samples was markedly dissimilar, with male bipolar subjects demonstrating a significantly increased rate of sexual abuse and combined sexual and physical abuse compared with unipolar male subjects.
Conclusion: The increased incidence of sexual abuse in women supports growing evidence of gender differences in sexual abuse among adult depressives. In contrast to literature reports, the finding that male bipolar patients have significantly increased rates of sexual abuse histories suggests differences in psychiatric depressive subgroups. This result may reflect the particular characteristics of our cohort (treatment resistant, privately insured, and educated). Further work will aid in characterizing sexual abuse prevalence in other male bipolar samples. 相似文献
64.
目的:探讨经鼻持续气道正压通气(nCPAP)治疗,对阻塞性睡眠呼吸暂停综合征(OSAS)合并高血压患者动态血压的影响。方法:22例男性患者行多导睡眠图(PSG)监测及动态血压检查确诊为OSAS合并高血压的患者,观察nCPAP治疗前后患者动态血压、多导睡眠图等多项指标变化。结果:nCPAP治疗后患者PSG参数明显改善:睡眠时最低SaO_2从(71.0±12.3)%上升到(91.7±7.3)%(P<0.01);RDI显著降低;同时24小时血压明显下降,治疗前血压(16.5±1.6/11.6±2.3Kpa),治疗后血压(13.7±1.5/9.3±1.4Kpa)(P<0.01)。结论:经鼻持续气道正压通气治疗阻塞性睡眠呼吸暂停综合征,不但可以纠正患者的呼吸暂停,改善临床症状,而且可能降低患者的血压。 相似文献
65.
Time-dependent astroglial changes after gamma knife radiosurgery in the rat forebrain 总被引:11,自引:0,他引:11
OBJECTIVE: Using an experimental rat model and a clinically relevant treatment dose, we performed gamma knife radiosurgery to define the hyperacute radiation effects in normal rat forebrain, the time dependence of the astrocytic reaction, and the participation of astrocytes in the healing process after single-dose gamma radiation injuries. METHODS: Seventy-one rats underwent radiosurgical treatment (4-mm collimator) of the caudate-putamen nucleus (single-fraction maximal dose of 100 Gy) and were killed at times ranging from 3 hours to 90 days. Serial cryostat brain sections were processed with the immunohistochemical avidin-biotin complex technique, using anti-glial fibrillary acidic protein as the primary antibody (to identify astrocytes). RESULTS: Vascular changes, including endothelial hyperplasia and vessel wall thickening, were identified as the earliest postradiation manifestations and continued throughout the observation period. Astrocytes reacted to the radiation injury with hyperplasia and hypertrophy. At earlier time points (3-24 h), proliferation was the predominant reaction. The expression of glial fibrillary acidic protein in the proliferating and hypertrophic astrocytes formed an initial peak in the adjacent corpus callosum 3 days after radiosurgery and peaked within the target site between 14 and 30 days. Astrocytic proliferation and hypertrophy were also observed in distant cortices (frontal, parietal, insular, and piriform cortices) and in the hippocampus. No necrosis was observed less than 30 days after irradiation. By Day 90, necrotic lesions with a mean diameter of 4 mm were identified, with glial scar at their peripheries. Astrocytic morphological features varied according to the distance from the necrosis. The irradiated side contained more glial fibrillary acidic protein-containing cells than did the nonirradiated contralateral side. CONCLUSION: During the early phase after radiation, vasculopathy was the first morphological change and may serve as the initiating factor for subsequent changes. Reactive astrocytes appeared not only at the target site but also in the surrounding regions; the severity of injury was determined by the distance from the target. 相似文献
66.
Bachiller Burgos J Varo Solís C Báez JM Estudillo F Juárez Soto A Soto Delgado M Beltrán Aguilar V González Moreno D Sánchez Bernal C Rodríguez-Rubio F 《Actas urologicas espa?olas》2000,24(8):673-676
The existence of a vesical diverticulum in the context of a congenital connective tissue disorder such as Ehlers-Danlos syndrome led us to consider the possibility of a relationship. Four types of diverticula can be found in the literature: congenital, acquired, iatrogenic and syndrome-associated. Within the later, Ehlers-Danlos syndromes type IV and IX, even type V, are associated to the existence of vesical diverticula. The potential spontaneous rupture of the diverticulum is a typical feature, as well as post-surgery relapse. The attitude towards such diverticula should be one of watchful waiting, and simple, plasty-free diverticulectomy on the bladder's neck is indicated when performing a surgical procedure. 相似文献
67.
68.
Varo Solís C Bachiller Burgos J Báez JM Estudillo F González Moreno D Alvarez-Ossorio Fernández JL Juárez Soto A Soto Delgado M Beltrán Aguilar VM 《Actas urologicas espa?olas》2000,24(7):594-598
Cystic-glandular cystitis is considered as part of the urothelial pre-neoplastic proliferative abnormalities. This group includes atypical hyperplasia. Von Brunn's nidus, and cystitis cystica. They are a consequence of the changes experienced at the urothelium level in response to inflammation, irritation or carcinogens. Diagnosis is mainly based in the pathoanatomical study of the biopsy obtained following endoscopic resection. The signs and symptoms it presents are varied and show a clear relationship to distribution and extension of cysts. Treatment is based in the removal of irritative factors. Cystectomy with urinary by-pass may be necessary if required by clinical evolution. 相似文献
69.
Effect of a cognitive behavioral intervention on reducing symptom severity during chemotherapy. 总被引:4,自引:0,他引:4
Charles Given Barbara Given Mohammad Rahbar Sangchoon Jeon Ruth McCorkle Bernadine Cimprich Andrzej Galecki Sharon Kozachik Albert Brady Mary Jo Fisher-Malloy Kathy Courtney Elizabeth Bowie 《Journal of clinical oncology》2004,22(3):507-516
PURPOSE: To describe a randomized trial of a cognitive behavioral intervention on reducing symptom severity among patients diagnosed with solid tumors and undergoing a first course of chemotherapy and to determine whether the intervention had an additive or interactive effect on symptom severity in the presence of supportive care medications. PATIENTS AND METHODS: Patients (N = 237) were accrued from comprehensive and community cancer centers, interviewed, and randomly assigned to either the experimental intervention (n = 118) or conventional care (n = 119). A symptom severity index, based on summed severity scores across 15 symptoms, was the primary outcome. Each patient's site of cancer, stage at diagnosis, chemotherapy protocols, and use of supportive medications were learned from medical records. RESULTS: Groups were equivalent at baseline, and attrition by characteristics by group was not different. The proportion of patients not receiving chemotherapy at 10 and 20 weeks did not differ by group. At the 10- and 20-week observations, there was a significant interaction between the experimental group and baseline symptom severity. Patients in the experimental group who entered the trial with higher symptom severity reported significantly lower severity at 10 and 20 weeks. Controlling for chemotherapy treatment status at follow-up and supportive care medications did not alter the effect of the experimental intervention. CONCLUSION: Compared with conventional care alone, the experimental intervention was effective among patients who entered the trial with higher levels of symptom severity. Age, sex, site or stage of cancer, and supportive medications did not modify the effect of this cognitive behavioral intervention on symptom severity. 相似文献
70.
Total vaginal or abdominal hysterectomy was considered an inadequate treatment method for invasive uterine cervix cancer. Usually the procedure was inadvertently performed on patients who were thought preoperatively to have benign or premalignant conditions. Between 1985 and 1993, 64 patients undergoing hysterectomy in the presence of invasive cervical cancer were treated with external radiation therapy and/or intracavitary radiotherapy. Preoperative diagnoses were carcinomain situ(36), severe dysplasia (2), and early invasive cancer (14), and others were benign disease. Overall 5-year survival and relapse-free survival rates were 75.8 and 77.5%, respectively. For patients in retrospective stage IA, IB, and IIB (gross residual after surgery), overall 5-year survival rates were 90.9, 88.8, and 27.9%, respectively. Thirteen patients developed treatment failure; most of them (10/13) were patients with gross residual disease. Patients with early invasive cervical cancer (stage IA) had no treatment-related failure. Prognostic factors affecting survival by univariate analysis were retrospective stage (P= 0.0000) and preoperative diagnosis (P= 0.0021). Tumor histology was marginally significant factor (P= 0.0938). By multivariate analysis, only retrospective stage was significant prognostic factor (P= 0.0001). Adjuvant radiotherapy appears to be an effective treatment method for patients with presumed stage IA and IB after inadvertent hysterectomy. Survival for patients with gross disease remaining after inappropriate hysterectomy is poor. So, early cancer detection and proper management with precise pretreatment staging is necessary to avoid inadherent hysterectomy, especially in cases of gross residual disease. 相似文献