全文获取类型
收费全文 | 16955篇 |
免费 | 660篇 |
国内免费 | 75篇 |
专业分类
耳鼻咽喉 | 534篇 |
儿科学 | 1528篇 |
妇产科学 | 584篇 |
基础医学 | 1002篇 |
口腔科学 | 1034篇 |
临床医学 | 1207篇 |
内科学 | 3025篇 |
皮肤病学 | 435篇 |
神经病学 | 997篇 |
特种医学 | 810篇 |
外科学 | 3720篇 |
综合类 | 341篇 |
一般理论 | 7篇 |
预防医学 | 503篇 |
眼科学 | 541篇 |
药学 | 899篇 |
中国医学 | 96篇 |
肿瘤学 | 427篇 |
出版年
2024年 | 18篇 |
2023年 | 185篇 |
2022年 | 202篇 |
2021年 | 350篇 |
2020年 | 270篇 |
2019年 | 318篇 |
2018年 | 459篇 |
2017年 | 401篇 |
2016年 | 490篇 |
2015年 | 433篇 |
2014年 | 603篇 |
2013年 | 835篇 |
2012年 | 990篇 |
2011年 | 1018篇 |
2010年 | 562篇 |
2009年 | 401篇 |
2008年 | 861篇 |
2007年 | 985篇 |
2006年 | 997篇 |
2005年 | 1038篇 |
2004年 | 1100篇 |
2003年 | 1026篇 |
2002年 | 997篇 |
2001年 | 678篇 |
2000年 | 598篇 |
1999年 | 515篇 |
1998年 | 188篇 |
1997年 | 154篇 |
1996年 | 160篇 |
1995年 | 80篇 |
1994年 | 70篇 |
1993年 | 54篇 |
1992年 | 96篇 |
1991年 | 88篇 |
1990年 | 72篇 |
1989年 | 73篇 |
1988年 | 40篇 |
1987年 | 32篇 |
1986年 | 34篇 |
1985年 | 35篇 |
1984年 | 30篇 |
1983年 | 16篇 |
1982年 | 10篇 |
1981年 | 14篇 |
1979年 | 14篇 |
1978年 | 10篇 |
1976年 | 9篇 |
1972年 | 11篇 |
1971年 | 8篇 |
1966年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
82.
A 14-year-old boy had a 1-month history of diplopia (due to a VI nerve palsy), motor ataxia and dizziness. Brain MRI showed
a 1.5-cm mass posterior to the pons. Histopathological examination of a biopsy specimen showed the lesion to be of viral origin.
After 3 months, the ataxia and dizziness had resolved and the MRI findings returned to normal. By 5 months the abducens paralysis
had also resolved. Viral encephalitis should be considered in the differential diagnosis of posterior fossa tumours.
Received: 20 March 1997 Accepted: 16 April 1997 相似文献
83.
E Balkan I Kiri?tio?lu A Gürpinar I Ozel K Sinmaz H Do?ruyol 《Archives of disease in childhood》1998,78(3):267-268
The role of sigmoidoscopic examination in the diagnosis, evaluation, and treatment of minor lower gastrointestinal bleeding was investigated. A hundred patients with minor rectal bleeding were examined by rigid sigmoidoscopy under general anaesthesia between January 1989 and July 1996. Patients who had bleeding secondary to infections, anal fissure, or haemorrhoids were excluded from study. Patients were reviewed retrospectively according to their diagnosis and endoscopic and histopathological findings. Twenty nine of these patients were girls and 71 boys; their ages ranged between 8 month and 14 years (mean 7.2 years). Endoscopic pathological findings were established in 60 patients; 32 had rectal polyps, 16 non-specific proctitis, four solitary rectal ulcers, three internal haemorrhoids, two ulcerative colitis, two Hirschsprung's enterocolitis, and one haemangioma. It is concluded that sigmoidoscopic examination should be performed for the diagnosis, prognosis, and choice of treatment in patients with minor rectal bleeding and the diagnosis should be confirmed histopathologically. 相似文献
84.
85.
Berkman MZ Iplikçioğlu AC Berkman MK Erbengi T San T Sav A 《Acta neurochirurgica》2000,142(9):1047-1054
Summary ? Background. Cerebral vasospasm after subarachnoid hemorrhage (SAH) has remained a major cause of morbidity and mortality in patients
with SAH. Excitatory neurotransmitters are gathered in the extracellular space during ischemia due to cerebral vasospasm and
initiate or stimulate a series of pathophysiological biochemical processes which consequently lead to neuronal death. Tizanidine
(Sandoz compound DS 103–282, 5-chloro-4,2 (2-imidazolin-2-yl-amino)-2,1,3-benzothiazol hydrochloride) is a centrally-acting
muscle relaxant and a selective α 2 adrenoreceptor agonist which shows its effect by stimulating presynaptic α 2 adrenoreceptors
in central ASPergic and GLUergic system by inhibiting aspartic acid and glutamic acid release. In this study, the effect of
Tizanidine on vasospasm was evaluated.
Methods. We used a femoral artery vasospasm model in rats which has been described by Okada et al. 60 rats were examined in three groups. The first group was used as control group (Control) (n=20), in the second group subarachnoid
hemorrhage was performed (SAH) (n=20), in the third group Tizanidine was administered in addition to SAH (SAH+Tizanidine administration)
(n=20). Animals in SAH+Tizanidine administration group received 0,3 mg/kg/day intraperitoneally for 7 days. Seven days after
the experiment, after perfusion-fixation, 10 mm segments of both femoral arteries were removed and the femoral artery was
prepared for light microscope examination, scanning and transmission electron microscopy and for morphometric analysis.
Results. There was a statistically significant difference between the electron, scanning and light microscopic observations and morphometric
analysis of SAH+Tizanidine administration group and SAH group, and no statistically significant difference between SAH+Tizanidine
administration group and control group.
Conclusion. This study has disclosed that Tizanidine administration before the vasospasm reduces ultrastructural and morphometric vasospastic
insult significantly. However, the clinical application of Tizanidine as a protective and therapeutic agent in cerebral vasospasm
needs further studies including the employment of clinically more relevant SAH models. 相似文献
86.
Mesoatrial shunt in Budd-Chiari syndrome 总被引:2,自引:0,他引:2
Emre A Kalayci G Ozden I Bilge O Acarli K Kaymakoğlu S Rozanes I Okten A Tekant Y Alper A Arioğul O 《American journal of surgery》2000,179(4):304-308
BACKGROUND: The operations with proven effects on survival in Budd-Chiari syndrome are shunt operations and liver transplantation. PATIENTS AND METHODS: Between 1993 and 1999 (June), 13 cases of Budd-Chiari syndrome have been treated surgically. Four cases had concomitant thrombosis of the inferior vena cava; the others had marked narrowing of the lumen due to the enlarged caudate lobe. Mesoatrial (n = 12) or mesosuperior vena caval (n = 1) shunts were constructed with ringed polytetrafluoroethylene grafts. RESULTS: The median portal pressure fell from 45 (range 32 to 55) to 20 (range 11 to 27) cm H(2)O (P <0.001). Two patients died in the early postoperative period. One patient who did not comply with anticoagulant treatment had a shunt thrombosis in the second postoperative year. The other 10 patients are alive without problems during a median 42 (range 1 to 76) months of follow-up. CONCLUSION: Mesoatrial shunt with a ringed polytetrafluoroethylene graft is effective in Budd-Chiari syndrome cases with thrombosis or significant stenosis in the inferior vena cava. 相似文献
87.
BACKGROUND: Nitric oxide (NO) may have an important role in the healing of burn wounds. This study investigated the effect of NO on experimentally induced burn wounds by preventing NO synthesis. METHODS: A total of 40 mice weighing 25 to 30 g were used in this study. The shaved skin on the back of the mice was immersed in 100 degrees C water for 10 seconds to achieve a partial-thickness scald burn. The mice were divided into two groups of 20. In group I (control group), 17.5 mg/kg of serum physiologic (placebo) was injected intraperitoneally two times a day for 15 days. In group II (study group), 17.5 mg/kg of aminoguanidine (NO synthase inhibitor) was injected intraperitoneally two times a day for 15 days. On day 15 of the burn, the animals were killed and the burn areas were investigated histologically. Histologic changes such as epithelial proliferation, abscess, collagen, and granulation tissue were evaluated. RESULTS: Epithelial proliferation, formation of collagen, and granulation tissue with rich capillaries observed in the control group were statically significantly higher than those observed in the study group (z = -2.022, p < 0.05; z = -2.02, p < 0.05; and z = -2.022, p < 0.05; respectively). CONCLUSION: We concluded that healing of the burn wound is delayed by preventing NO synthesis. 相似文献
88.
Aktuğ T Hakgüder G Sarioğlu S Akgür FM Olguner M Pabuçcuoğlu U 《Journal of pediatric surgery》2000,35(3):515-518
BACKGROUND: Ependymomas, the common glial tumors of the spinal cord, occur occasionally outside the central nervous system and are called exstraspinal ependymomas (EEP). EEPs are found primarily in sacrococcygeal region during childhood. The pathogenesis and the treatment of the sacrococcygeal (SC) ependymomas are still controversial. Therefore, we present our case with metaanalysis of other case reports to determine the optimal treatment modality for SC EEPs. METHODS: A metaanalysis of case reports of SC EEPs, including the current case, was conducted. Also all available case reports of EEPs, without age limit, were analyzed to determine the distribution of EEPs localization. RESULTS: EEPs usually are found in teratoma localizations such as the SC area, ovary, paraovarian structures, and medastinum. The distribution of EEPs localization differs with age. Local recurrence rate of EEPs after coccyx excision is zero, however, it increases to 71% when the coccyx was left behind. CONCLUSION: The identical clinical characteristics of the SC teratomas and EEPs imply that the SC EEPs may be monophasic teratomas as their ovarian counterparts are named. Coccyx excision is an important part of the surgical treatment of these tumors, with an apparent decrease in the recurrence rate. 相似文献
89.
90.
E E Buyukbayrak C Turan O Unal R Dansuk B Cengizo?lu 《The journal of maternal-fetal & neonatal medicine》2004,15(2):120-125
OBJECTIVE: The purpose of this study was to determine the reliability of the vaginal washing-fluid prolactin assay for the diagnosis of premature rupture of membranes (PROM) and to determine a diagnostic cut-off value. STUDY DESIGN: Seventy pregnant women between 11 and 40 weeks of gestation who were admitted with vaginal fluid leakage were included in the study group, and were then further subdivided into two subgroups according to amniotic fluid pooling and nitrazine paper test results. Group 1 was the 'confirmed PROM group', positive for both pooling and nitrazine (38 patients). Group 2 was the 'suspected but unconfirmed PROM group' which had possible pooling and/or nitrazine (32 patients). Seventy pregnant women between 11 and 40 weeks of gestation without any complaint and complication were included in the control group (group 3). All patients underwent vaginal washing-fluid sampling and prolactin level determination. For the statistical analysis one-way analysis of variance, Tukey multiple comparison test, chi2 test and receiver operating characteristic (ROC) curve analysis were used. RESULTS: Geometric mean values of vaginal washing-fluid prolactin levels were 616.59 microIU/ml for group 1, 23.98 microIU/ml for group 2 and 10 microIU/ml for group 3 (p < 0.0001). The optimal diagnostic cut-off value was found to be 30 microIU/ml with 95% sensitivity, 78% specificity, 84% positive predictive value, 93% negative predictive value, 87% accuracy and 11.30 relative risk. CONCLUSIONS: We recommend vaginal washing-fluid prolactin level determination as an alternative diagnostic method for PROM. 相似文献