全文获取类型
收费全文 | 17429篇 |
免费 | 916篇 |
国内免费 | 156篇 |
专业分类
耳鼻咽喉 | 138篇 |
儿科学 | 359篇 |
妇产科学 | 596篇 |
基础医学 | 1911篇 |
口腔科学 | 449篇 |
临床医学 | 1389篇 |
内科学 | 4475篇 |
皮肤病学 | 300篇 |
神经病学 | 1853篇 |
特种医学 | 735篇 |
外科学 | 2628篇 |
综合类 | 50篇 |
一般理论 | 1篇 |
预防医学 | 598篇 |
眼科学 | 312篇 |
药学 | 1043篇 |
中国医学 | 24篇 |
肿瘤学 | 1640篇 |
出版年
2024年 | 22篇 |
2023年 | 179篇 |
2022年 | 349篇 |
2021年 | 610篇 |
2020年 | 393篇 |
2019年 | 484篇 |
2018年 | 609篇 |
2017年 | 414篇 |
2016年 | 496篇 |
2015年 | 562篇 |
2014年 | 767篇 |
2013年 | 906篇 |
2012年 | 1392篇 |
2011年 | 1391篇 |
2010年 | 770篇 |
2009年 | 703篇 |
2008年 | 1107篇 |
2007年 | 1110篇 |
2006年 | 1064篇 |
2005年 | 962篇 |
2004年 | 931篇 |
2003年 | 803篇 |
2002年 | 684篇 |
2001年 | 160篇 |
2000年 | 163篇 |
1999年 | 174篇 |
1998年 | 154篇 |
1997年 | 113篇 |
1996年 | 117篇 |
1995年 | 104篇 |
1994年 | 73篇 |
1993年 | 63篇 |
1992年 | 94篇 |
1991年 | 91篇 |
1990年 | 54篇 |
1989年 | 55篇 |
1988年 | 42篇 |
1987年 | 43篇 |
1986年 | 41篇 |
1985年 | 32篇 |
1984年 | 38篇 |
1983年 | 31篇 |
1982年 | 27篇 |
1981年 | 20篇 |
1980年 | 10篇 |
1978年 | 8篇 |
1976年 | 8篇 |
1971年 | 8篇 |
1970年 | 11篇 |
1969年 | 7篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
Acute infectious diarrhea 总被引:1,自引:0,他引:1
Marignani M Angeletti S Delle Fave G 《The New England journal of medicine》2004,350(15):1576-7; author reply 1576-7
62.
Professor Claude Huguet M.D. Joseph Harb M.D. Stefano Bona M.D. 《World journal of surgery》1990,14(5):619-622
Twenty-two patients had coloanal anastomoses performed after resection of low rectal tumors (16 adenocarcinomas and 6 large degenerated villous adenomas). The patients had an average age of 72 years (range: 62–85). A hand-sewn anastomosis was performed between a J-shaped colonic reservoir and the anal sphincter, except in 3 patients who underwent a straight end-to-end coloanal suture without pouch. A defunctionalized stoma was made in 18 cases. Mortality within 30 days of operation was 9%. Specific complications occurred in 2 patients (9%). Mean follow-up in this series was 20.2±11.7 months (± standard deviation). Fifteen patients were alive and free of disease up to 54 months after surgery. One patient was found to have local recurrence at 19 months. The actuarial 3-year survival rate was 73% in the whole group (operative mortality included). Functional results were good in 16 of 19 patients, with an average 1.8–2.9 stools/24 hours and the continence rate was good. Three patients had complications requiring a permanent colostomy. From these preliminary results, coloanal anastomosis appears to be satisfying in regard to oncologic results and affords good anal function, even in the elderly patient (over 62 years of age).
Presented at the Société Internationale de Chirurgie in Toronto, Ontario, Canada, September, 1989. 相似文献
Resumen Veintidos pacientes fueron sometidos a anastomosis después de la resecciôn de tumores rectales bajos (16 adenocarcinomas y 6 grandes adenomas vellosos con degeneración carcinomatosa), con edad promedio de 72 años (rango: 62–85). Se practicó anastomosis manual entre un reservorio colónico construído en forma de J y el esfínter anal, excepto en 3 pacientes sometidos a sutura colo-anal términoterminal sin construcción de bolsa. Se practicó un estoma de funcionante en 18 casos. La mortalidad en los primeros 30 días después de la operación fue 9%. Se presentaron complicaciones específicas en 2 pacientes (9%). El seguimiento promedio en la serie fue de 20.2±11.7 meses (± de). Quince pacientes se encuentran vivos y libres de enfermedad hasta por 54 meses. Un paciente demostró recurrencia local a los 19 meses. La tasa actuarial de sobrevida a 3 anos es de 73% para el grupo total (incluyendo la mortalidad operatoria). Los resultados funcionales fueron buenos en 16 de 19 pacientes, con un promedio de 1.8 a 2.9 deposiciones/24 horas y buena continencia. Tres pacientes presentaron complicaciones que requirieron colostomía permanente. Según estos resultados preliminares, la anastomosis colo-anal aparece como un procedimiento satisfactorio en relación con los resultados oncológicos y provee buena función anal aun en el paciente anciano (mayor de 62 años).
Résumé Vingt-deux patients ont eu une anastomose coloanale après résection d'une tumeur rectale basse (16 adénocarcinomes et 6 tumeurs villeuses larges dégénérées). L'âge moyen des patients était de 72 ans (extrêmes 62 et 85 ans). Dix-neuf patients ont eu une anastomose manuelle entre un réservoir colique en J et le canal anal, alors que 3 ont eu une anastomose manuelle termino-terminale coloanale sans réservoir. Une colostomie de décharge a été ajoutée dans 18 cas. La mortalité des 30 premiers jours postopératoires a été de 9%. Deux patients (9%) ont eu des complications spécifiques. La survie moyenne a été de 20.2±11.7 mois (± ET). A 54 mois, 15 patients sont en vie et sans maladie. Une récidive locale a été décelée chez un patient à 19 mois. La survie actuarielle à 3 ans est de 73% pour l'ensemble des patients (mortalité opératoire incluse). Les résultats fonctionnels étaient bons chez 16 des 19 patients. Ces patients avaient en moyenne 1.8 à 2.9 selles par 24 heures et la continence était bonne. Trois patients avaient des complications nécessitant une colostomie permanente. D'après ces premiers résultats, il semble que l'anastomose coloanale donne de bons résultats du point de vue oncologique avec conservation d'une fonction sphinctérienne satisfaisante, même chez le patient âgé (plus de 62 ans).
Presented at the Société Internationale de Chirurgie in Toronto, Ontario, Canada, September, 1989. 相似文献
63.
Dominici Carlo Nicotra Maria Rita Alemaà Stefano Bosman Cesare Castello Manuel A. Donfrancesco Alberto Gallo Pietro Natali Pier Giorgio 《Journal of neuro-oncology》1997,31(1-2):57-64
In neuroblastoma, high levels of mRNA for p14h
trkA
and p75
LNGFR
neurotrophin receptors are predictive of favorable outcome. Their evaluation by Northern blot, however, requires substantial amounts of tissue and this prevents their routine evaluation as well as the possibility for multicenter studies to be easily carried out. In an attempt to overcome these limitations, the feasibility and reliability of determining both neurotrophin receptors on cryostat sections by immunohistochemistry were assessed, and these findings were compared to those obtained from Northern blot analysis. Primary tumor samples from 28 untreated patients at all stages were evaluated by using H10 anti-p140
trkA
and ME20.4 anti-p75
LNGFR
mAbs. Although weak, positiveimmunostaining was found in 9 of 28 tumors for p140
trkA
and in 5 of 28 tumors for p75
LNGFR
. As compared to Northern blot, the concordance rate was 79% (22 of 28 cases) for p140
trkA
(p < 0.05) and 71% (20 of 28 cases) for p75
LNGFR
(p < 0.05). No case negative for Northern blot was found to be positive with immunohistochemistry. Since only high mRNA levels for both receptors have been shown to be clinically relevant, their immunohistochemical detection, although less sensitive than Northern blot, can be just as sufficient and reliable as a prognostic tool, and possibly with a better cost-benefit ratio. 相似文献
64.
Caterina Mariotti Graziella Uziel Franco Carrara Marina Mora Alessandro Prelle Valeria Tiranti Stefano DiDonato Massimo Zeviani 《Journal of neurology》1995,242(9):547-556
A male infant, born from consanguineous parents, suffered from birth with a progressive neuromuscular disorder characterized by psychomotor delay, hypotonia, muscle weakness and wasting, deep-tendon areflexia and spastic posture. High levels of lactic acid in blood and cerebrospinal fluid suggested a mitochondrial respiratory chain defect. Muscle biopsy revealed raggedred and cytochromec oxidase-negative fibres, lipid accumulation and dystrophic changes. Multiple defects of respiratory complexes were detected in muscle homogenate, but cultured fibroblasts, myoblasts and myotubes were normal. Southern blot analysis showed markedly reduced levels of mitochondrial DNA (mtDNA) in muscle, while lymphocytes, fibroblasts and muscle precursor cells were normal. Neither depletion of mtDNA nor abnormalities of the respiratory complexes were observed in innervated muscle fibres cultured for as long as 4 months. No mutations were observed in two candidate nuclear genes,mtTFA andmtSSB, retro-transcribed, amplified and sequenced from the proband's mRNA. Sequence analysis of the mtDNA D-loop and of the origin of replication of the mtDNA light strand failed to identify potentially pathogenic mutations of these replicative elements in the proband's muscle mtDNA. Our findings indicate that mtDNA depletion is due to a nuclear encoded gene and suggest that the abnormality underlying defective mtDNA propagation must occur after muscle differentiation in vivo. 相似文献
65.
The effect of accident mechanisms and initial findings on the long-term course of whiplash injury 总被引:6,自引:0,他引:6
Matthias Sturzenegger Bogdan P. Radanov Giuseppe Di Stefano 《Journal of neurology》1995,242(7):443-449
The aim of this study was to assess the relationships between accident mechanisms as well as initial findings and the long-term course of whiplash injury. A representative sample of 117 consecutive patients referred by primary care physicians was followed-up over 12 months. Fractures or dislocations of the cervical spine, head trauma and pre-existing neurological disorders were exclusion criteria. The interval between the accident and the baseline examination was 7.4 days (SD 4.2 days). Assessment included accident features (e.g. passenger position in the car, head restraint, head position, type of collision), initial symptoms (e.g. intensity and onset of pain, symptoms of neurological dysfunction, multiple symptom score), and signs (restricted neck movement, neurological deficits). At the 1-year examination, patients were divided into an asymptomatic and a symptomatic group and were compared with respect to accident features and baseline findings. Twenty-four percent of patients were still symptomatic after 1 year. Analysing accident mechanisms separately, rotated or inclined head position was the primary feature related to symptom persistence (P=0.005). The symptomatic group scored higher at baseline on the multiple symptom rating (P=0.004) and had a higher incidence of initial headache (P=0.004) and neurological symptoms (P=0.008) together with a higher intensity of headache (P=0.0002) and neck pain (P=0.0009). The following set of initial variables predicted persistence of symptoms at 1 year (logistic regression): intensity of neck pain (P=0.001) and headache (P=0.009), rotated or inclined head position (P=0.02), unpreparedness at the time of impact (P=0.01) and car stationary when hit (P=0.01). In conclusion, accident mechanisms and initial findings suggestive of more severe injury were significantly related to long-term persistence of symptoms after whiplash injury.This study was supported by the Swiss National Science Foundation (project number: 3.883-0.88) and the Swiss Accident Insurance Company (Schweizerische Unfallversicherungsanstalt), Berne 相似文献
66.
Identification of the central vestibular projections in man: a positron emission tomography activation study 总被引:4,自引:0,他引:4
Gabriella Bottini Roberto Sterzi Eraldo Paulesu Giuseppe Vallar Stefano F. Cappa Francesco Erminio Richard E. Passingham Chris D. Frith Richard S. J. Frackowiak 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1994,99(1):164-169
The cerebral representation of space depends on the integration of many different sensory inputs. The vestibular system provides one such input and its dysfunction can cause profound spatial disorientation. Using positron emission tomography (PET), we measured regional cerebral perfusion with various vestibular stimulations to map central vestibular projections and to investigate the cerebral basis of spatial disorientation. We showed that the temporoparietal cortex, the insula, the putamen, and the anterior cingulate cortex are the cerebral projections of the vestibular system in man and that the spatial disorientation caused by unilateral vestibular stimulation is associated with their asymmetric activation. 相似文献
67.
Saviano MS Fundarò S Gelmini R Begossi G Perrone S Farinetti A Criscuolo M 《Surgery today》1999,29(2):174-177
(Received for publication on Apr. 28, 1997; accepted on May 15, 1998) 相似文献
68.
p53 Accumulation Is a Prognostic Factor in Intestinal-Type Gastric Carcinoma but Not in the Diffuse Type 总被引:2,自引:0,他引:2
Roviello F Marrelli D Vindigni C De Stefano A Spina D Pinto E 《Annals of surgical oncology》1999,6(8):739-745
Background: The prognostic value of p53 nuclear accumulation in gastric cancer is still unclear, as shown by the discordant results still reported in the literature. In this study, we evaluated the correlation between p53 accumulation and long-term survival of patients resected for intestinal and diffuse-type gastric cancer.Methods: Eighty-three patients with carcinoma of the intestinal type and 53 patients with carcinoma of the diffuse type were included in the study. Immunohistochemical staining of the paraffin sections was performed by using monoclonal antibody DO1; cases were considered positive when nuclear immunostaining was observed in 10% or more of the tumor cells. Prognostic significance of different variables was investigated by univariate and multivariate analysis.Results: p53 positivity was found in 51.8% of intestinal-type and 50.9% of diffuse-type cases. No significant correlation between the rate of p53 overexpression and age, sex, tumor location, tumor size, depth of invasion, lymph node involvement, distant metastases, and surgical radicality was found in the two groups of patients. A statistically significant difference in survival rate was observed between p53-negative and p53-positive cases in the intestinal type (P < .05), confirmed by multivariate analysis (P < .005; relative risk = 3.09). On the contrary, no correlation with survival was found in diffuse-type cases according to p53 overexpression.Conclusions: These results suggest that the immunohistochemical detection of p53 accumulation is a useful indicator of poor prognosis in the intestinal but not in the diffuse type of gastric cancer, and are indicative of distinct molecular pathways and pattern of progression in the two histotypes. 相似文献
69.
70.
Calcagni A Ciattini PG Di Stefano A Duprè S Luisi G Pinnen F Rossi D Spirito A 《Il Farmaco; edizione pratica》1999,54(10):673-677
This paper reports the synthesis of tauryl dipeptides related to carnosine. In particular H-Tau-His-OH (5), H-Tau-His(pi-Me)-OH (6) and H-Tau-His(tau-Me)-OH (9) are described. The enzyme carnosinase has been isolated from pig kidney and after purification has been used to test the stability and the inhibitory activity of the three new analogues. H-Tau-His-OH (5) and H-Tau-His(tau-Me)-OH (9) were found to possess weak inhibitory properties towards carnosinase, while H-Tau-His(pi-Me)-OH (6) proved to be devoid of any significant activity. All the three sulfonamido pseudopeptides 5, 6 and 9 show stability to carnosinase activity. 相似文献