全文获取类型
收费全文 | 6940篇 |
免费 | 659篇 |
国内免费 | 180篇 |
专业分类
耳鼻咽喉 | 58篇 |
儿科学 | 244篇 |
妇产科学 | 169篇 |
基础医学 | 299篇 |
口腔科学 | 120篇 |
临床医学 | 1353篇 |
内科学 | 1648篇 |
皮肤病学 | 132篇 |
神经病学 | 410篇 |
特种医学 | 250篇 |
外科学 | 1802篇 |
综合类 | 16篇 |
预防医学 | 356篇 |
眼科学 | 327篇 |
药学 | 158篇 |
肿瘤学 | 437篇 |
出版年
2023年 | 111篇 |
2021年 | 82篇 |
2020年 | 114篇 |
2019年 | 56篇 |
2018年 | 150篇 |
2017年 | 181篇 |
2016年 | 201篇 |
2015年 | 160篇 |
2014年 | 251篇 |
2013年 | 339篇 |
2012年 | 184篇 |
2011年 | 187篇 |
2010年 | 284篇 |
2009年 | 402篇 |
2008年 | 215篇 |
2007年 | 150篇 |
2006年 | 189篇 |
2005年 | 156篇 |
2004年 | 141篇 |
2003年 | 131篇 |
2002年 | 121篇 |
2001年 | 160篇 |
2000年 | 118篇 |
1999年 | 171篇 |
1998年 | 187篇 |
1997年 | 205篇 |
1996年 | 311篇 |
1995年 | 262篇 |
1994年 | 204篇 |
1993年 | 120篇 |
1992年 | 138篇 |
1991年 | 157篇 |
1990年 | 81篇 |
1989年 | 145篇 |
1988年 | 119篇 |
1987年 | 96篇 |
1986年 | 111篇 |
1985年 | 105篇 |
1984年 | 98篇 |
1983年 | 83篇 |
1982年 | 75篇 |
1981年 | 67篇 |
1980年 | 84篇 |
1979年 | 50篇 |
1978年 | 68篇 |
1976年 | 47篇 |
1975年 | 52篇 |
1972年 | 45篇 |
1964年 | 49篇 |
1963年 | 47篇 |
排序方式: 共有7779条查询结果,搜索用时 15 毫秒
31.
Panu R Bo Minelli L Botti M Gazza F Acone F Ragionieri L Palmieri G 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2003,275(2):1102-1108
The aim of this study was to locate in male pigs the sensory and autonomic ganglia innervating the retractor penis muscle (RPM), which was taken as an experimental model of the genital smooth musculature. The retrograde neuronal tracers horseradish peroxidase (HRP), Fast Blue (FB), and diamidino yellow (DY) were injected into the bulbopenile portion of the left RPM. The tracers highlighted a different affinity for the neuronal structures, although labelled cells supplying the RPM were generally found in bilateral dorsal root ganglia (DRGs, S1-S3), in bilateral paravertebral ganglia (PaGs, L2-S3), and in the left and right caudal mesenteric ganglia (CMGs). The mean number of labelled FB cells was 795 (range, 645-952) in DRGs, 16046.25 (range, 10226-18742) in PaGs, and 635.25 (range, 333-786) in CMGs. The mean diameter of pseudounipolar DRG cells was 60-75 microm, while the multipolar neurons of PaGs and CMGs had dimensions varying between 20-50 microm and 20-30 microm, respectively. 相似文献
32.
Silvia Natoli Marco Ciotti Pierpaolo Paba Gian Piero Testore Giampiero Palmieri Augusto Orlandi Alessandro Fabrizio Sabato Francesca Leonardis 《Journal of clinical virology》2006,37(1):72-74
BACKGROUND: Lethal varicella in immunocompetent hosts is rare and its pathogenesis is largely unknown. The discovery of glycoprotein E (gE) mutants showing attributes consistent with increased virulence in vitro and in animal models, provided a possible molecular mechanism underlying a more aggressive virus infection. However, these mutants have never been associated with unusually severe clinical cases. OBJECTIVES: To varicella-zoster virus (VZV) mutations that correlate with increased virulence. RESULTS: We report a case of fatal hepatitis caused by a VZV bearing a novel mutation on the 3B3 monoclonal antibody epitope of gE in an immunocompetent host. CONCLUSIONS: This report describes a mutant VZV responsible for an aggressive clinical course in an immunocompetent host. Linking these severe clinical presentations of VZV infection to virus mutations might provide insights into the underlying pathogenic mechanisms. 相似文献
33.
A retrospective study of all ileogastrostomy procedures (n=26) performed in 1993 by one surgeon (IGMC) was carried out to investigate the hypothesis that Helicobacter pylori may be implicated in certain severe cases of postoperation nausea and diarrhea. Ten of 26 persons (38.5%) displayed nausea
and notable diarrhea (greater than or equal to ten bowel movements per day), seven of which warranted upper GI investigation.
One hundred per cent (seven of seven) of these persons were found to possess H. pylori upon C-14 breath test. In four of six cases eradication therapy (1 g amoxicillin b.i.d./20 mg omeprazole b.i.d. for 2 weeks)
corresponded with a resolution of severe nausea and diarrhea (one additional case involved omeprazole use only), suggesting
that H. pylori should be considered as a possible cause of these symptoms post-ileogastrostomy. Additionally, in four of seven cases persons
were re-tested (C-14 breath analysis) at least 1 month post-therapy and in this group three persons were found to be free
of the organism. All three cases of notable diarrhea and nausea resolved with treatment, providing the strongest evidence
for a possible association between infection and these symptoms. 相似文献
34.
35.
J. Byrne MB BCh FRCSI J. W. Hallett Jr. MD C. F. Kollmorgen MD M. M. Gayari BS W. Davies MD FRCSC 《Annals of vascular surgery》1996,10(2):156-165
Our aim was to examine the feasibility of a totally laparoscopic insertion of a bifurcated aortofemoral bypass graft in a canine model and to compare the surgical results with those in control animals undergoing standard grafting and laparoscopic-assisted bypass procedures. Using a six-port approach, we exposed and cross clamped the aorta, tunneled a bifurcated Dacron graft, and performed an end-to-end aortic anastomosis while maintaining pneumoperitoneum by means of CO2. Proximal anastomoses were performed with 4/0 double-ended continuous Prolene sutures and distal anastomoses were performed through standard groin incisions. Total operating and aortic cross-clamp times were measured as was the total blood loss for each procedure. Clinical outcome was also documented. Eight female laboratory-bred hounds underwent successful totally laparoscopic aortobifemoral bypass grafting, eight underwent open grafting, and eight underwent laparoscopic-assisted bypass. Mean operating time was 193 minutes in the animals undergoing totally laparoscopic insertion vs. 156 minutes in the open group and 180 minutes in the laparoscopic-assisted group. Aortic cross-clamping time was also significantly longer at 87 minutes vs. 43 minutes (p < 0.001)=" in=" the=" totally=" laparoscopic=" group,=" but=" blood=" loss=" was=" less.=" all=" eight=" laparotomy=" and=" laparoscopic-assisted=" dogs=" were=" still=" alive=" with=" no=" complications=" at=" 28=" days,=" whereas=" three=" of=" the=" eight=" in=" the=" totally=" laparoscopic=" group=" showed=" evidence=" of=" temporary=" paraplegia.=" this=" experimental=" study=" demonstrates=" that=" a=" totally=" laparoscopic=" approach=" can=" be=" used=" to=" insert=" a=" bifurcated=" aortofemoral=" bypass=" with=" a=" proximal=" end-to-end=" anastomosis=" but=" currently=" does=" not=" save=" time=" and=" may=" increase=" the=" risk=" of=" neurologic=">Presented at the Twentieth Annual Meeting of the Peripheral Vascular Surgery Society, New Orleans, La., June 10, 1995. 相似文献
36.
Frydenberg HB 《Obesity surgery》1991,1(3):315-317
Many forms of gastric banding have been described and high reoperation rates reported. These can be mainly attributed to excess
vomiting associated both with and without stenosis. Reflux oesophagitis and the ‘sump’ effect may be other causes. This paper
examines the problems associated with banding leading to revisional surgery and introduces a new technique, ‘fundal supporting
suture’, to correct these problems. Preliminary results on 126 bandings without the modification and 22 with the modification
are presented. 相似文献
37.
Increased placental apoptosis in intrauterine growth restriction 总被引:2,自引:0,他引:2
Stephen C. Smith MB ChB Philip N. Baker DM E.Malcolm Symonds MD 《American journal of obstetrics and gynecology》1997,177(6):1395-1401
OBJECTIVES: Our purpose was to investigate a possible role for apoptosis in the pathophysiologic mechanisms of intrauterine growth restriction. STUDY DESIGN: Placental samples were obtained from 43 uncomplicated third-trimester pregnancies and from 26 pregnancies complicated by intrauterine growth restriction. The definition used to identify cases of intrauterine growth restriction depended on three criteria: clinical evidence of suboptimal growth, ultrasonographic evidence of deviation from an appropriate growth percentile, and individualized birth weight ratios <10th percentile. Light microscopy was used to quantify the incidence of apoptosis. Electron microscopy and TUNEL (terminal deoxynucleotidyl transferase–mediated deoxyuridine triphosphate nick end labeling) staining were used to confirm the occurrence of apoptosis. RESULTS: Quantification of apoptosis (medians and interquartile ranges) resulted in the following values: normal third trimester (n = 43) 0.14% of cells (0.08% to 0.20%) and intrauterine growth restriction third trimester (n = 26) 0.24% of cells (0.16% to 0.29%). The incidence of apoptosis was significantly higher in placentas from pregnancies with intrauterine growth restriction compared with normal third-trimester placentas (p < 0.01, Mann Whitney U test). CONCLUSIONS: These results suggest that apoptosis may play a role in the pathophysiologic mechanisms of intrauterine growth restriction.(Am J Obstet Gynecol 1997;177:401) 相似文献
38.
39.
Topiramate depresses carbachol-induced plateau potentials in subicular bursting cells 总被引:1,自引:0,他引:1
Intracellular recordings were made in an in vitro slice preparation to establish whether the antiepileptic drug topiramate reduces the depolarizing plateau potentials (PPs) induced in the rat subiculum by intracellular pulses of depolarizing current, in the presence of the cholinergic agonist carbachol (CCh, 70-100 microM). PPs lasted up to about 2 s, and disappeared during application of the muscarinic receptor antagonist atropine. Topiramate (10-100 microM, n = 22 neurons) decreased and eventually abolished in a dose-dependent manner these PPs, even when the function of excitatory amino acid and GABAA receptors was blocked. Hence, topiramate depresses muscarinic receptor-dependent PPs in the rat subiculum, thus suggesting that this form of excitation may represent a target for the mechanism of action of this antiepileptic compound. 相似文献
40.
A TEN-YEAR HOSPITAL SURVEY OF EYELID CANCER 总被引:1,自引:0,他引:1
IAN C. FRANCIS FRACO FRACS PETER. S. BENECKE MB BS MEDDUMA. B. KAPPAGODA FRACO FRACS 《Clinical & experimental ophthalmology》1984,12(2):121-127
Two hundred and four cases of malignant eyelid tumours, managed at the Concord Hospital, were reviewed. These cases spanned a ten-year period between 1973 and 1982 and all were treated surgically. The nature of each tumour was confirmed by histopathological examination. Included in this review were the site of the tumour, the tumour pathology, the surgical management, the type of surgeon involved, the ocular complications, the management of recurrences and any mortality. The importance of preventing recurrences by adequate initial surgery with frozen section control is emphasized. 相似文献