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31.
H. Hansen H. J. Sommer W. Eichelkraut 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1987,370(2):141-151
Zusammenfassung In einer tierexperimentellen Studie wurde die Durchblutung nach Anlage einer handgenähten und geklammerten End-zu-End-Anastomose am Schweinedickdarm verglichen. Bei keinem der 15 Tiere trat ein Nahtleck auf. Im Bereich handgeknoteter Fäden konnten einzelne umschriebene minderdurchblutete Gebiete festgestellt werden, die am 7. und 14. postoperativen Tag deutlich sichtbar wurden, wenn die Anastomosen vermehrt vascularisiert waren. Bei den Klammernähten wurden solche Ausfälle der Gewebsdurchblutung nicht gesehen. Die intramuralen Arterien zogen unbehindert durch die B-förmig gestalteten Klammern hindurch. Ein unauffälliges Gefäßmuster und eine abgeschlossene Anastomosenheilung wurden bei den Klammernähten nach 3 Wochen und bei Handnähten nach 4 Wochen beobachtet.
Blood supply of stapled and sutured colonic anastomoses
Summary The blood supply of end-to-end staple and suture lines in the pig colon was compared. In 15 operated animals there was no anastomotic leak. Sporadic circumscribed areas of restricted circulation could be noticed in hand-sewn anastomoses. This effect was marked on the 7th and 14th postoperative day, when vascularisation of the anastomoses was increased. Such lack of vascular supply was not seen in stapled anastomoses. The intramural arteries passed through the B-shaped staples without hindrance. An unremarkable vascular pattern and a completed healing of the anastomoses were observed after 3 weeks in staple lines and after 4 weeks in suture lines.
Herrn Prof. Dr. Dr. h.c. F. Stelzner zum 65. Geburtstag gewidmet 相似文献
32.
Small rodents of the species Rattus norvegicus and Rattus rattus have been captured between 1986 and 1988 in several areas of Southern Portugal. A total of 135 animal specimens were examined for hantaviral antigens in lung sections and 5 have been found positive. Some of the rodents were shown to have serum antibodies as detected by immunofluorescence in titres up to 1:256. This investigation proves for the first time the presence of Hantavirus in wild rodent populations of Portugal. 相似文献
33.
I Moosbrugger P Bischoff J P Beck B Luu J Borg 《International journal of immunopharmacology》1992,14(2):293-302
n-Hexacosanol (hexa), a long chain fatty alcohol extracted from Hygrophila erecta, has proved to possess neurotrophic activities on cultured neurons, and to attenuate the degeneration of cholinergic neurons after injury. In the present study, we show that hexa has also interesting properties on macrophages, a cell type largely represented in the brain: when added to mice resident peritoneal macrophages, it provokes significant morphological changes, and increases their phagocytosis capacity. These results may indicate that some membrane properties involved in these different effects and in macrophage functions are affected by n-hexacosanol, but other sites of action could also be considered. 相似文献
34.
Rebecca J Sommer Adam J Hume Jessica M Ciak John J Vannostrand Megan Friggens Mary K Walker 《Toxicological sciences》2005,83(2):363-371
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) causes cardiovascular toxicity in laboratory animals, including alteration in several processes in which beta-adrenergic receptor (beta-AR) signaling plays important roles. Thus, our laboratory investigated the effects of TCDD on beta-AR expression and signal transduction. Fertile chicken eggs were injected with vehicle (corn oil), 0.24 or 0.3 pmol TCDD/g egg on incubation day 0 (D0) or D5. On D10, heart function was assessed by ECG in ovo. Exposure to TCDD increased the incidence of arrhythmias and decreased the positive chronotropic responsiveness of the heart to isoproterenol. The reduced beta-AR responsiveness was, in part, independent of any overt morphological changes in the heart as chick embryos exposed to TCDD on D5 displayed an intermediate responsiveness to beta-AR agonist in the absence of the dilated cardiomyopathy observed in chick embryos exposed to TCDD on D0. TCDD did not decrease the chronotropic response of the heart to agents that stimulate signals downstream of the beta-AR. In fact, TCDD-exposed embryos were more sensitive than controls to forskolin, increasing heart rates (HR) 21.8 +/- 3.5 beats per min (bpm) above baseline versus control values at 6.3 +/- 2.7 bpm above baseline. TCDD exposure also augmented the negative chronotropic response of the heart to verapamil, decreasing HR -23.2 +/- 7.4 bpm relative to baseline versus control embryos at -12.7 +/- 5.9 bpm below baseline. Finally, the mean cardiac beta1-AR mRNA expression in D10 embryos was not significantly altered by exposure to TCDD on D0. These findings establish that a functional end point of the developing chick heart is sensitive to TCDD exposure and that the TCDD-induced reduction in beta-AR responsiveness may result from alterations in signal transduction upstream of adenylyl cyclase. 相似文献
35.
Vendeville B.; Baran D.; Gascon-Barre M.; Rubin E.; Luu T.; Vallieres S. 《Nephrology, dialysis, transplantation》1995,10(11):2020-2026
BACKGROUND.: Mercuric chloride (HgCl2 induces a lymphoproliferative disorderand autoimmune glomerulonephritis in Brown Norway (BN) rats.This syndrome is the consequence of T cell-dependent polyclonalB cell activation and autoantibody production. We have previouslyshown that HgCl2-induced autoimmune perturbations can be preventedin BN rats by the administration of cyclosporin A (CsA). Themost potent vitamin D3 metabolite 1,25(OH)2 D3 (Vit D3) sharescertain immunomodulatory properties with CsA. We therefore choseto compare the effects of Vit D3 to those of CsA in BN ratstreated with HgCl2 in order to establish whether Vit D3 eitheralone or in combination with CsA can attenuate an autoimmunesyndrome in vivo. METHODS.: BN rats were treated with HgCl2 according to a standard protocol.Subgroups of rats were also given CsA alone, Vit D3 or syntheticanalogues of Vit D3 alone, or combinations of both agents. Differentdoses and routes of administration were compared. The followingmarkers of disease activity were evaluated: mortality, peakproteinuria, serum IgE concentrations, and renal immunoglobulindeposition. RESULTS.: Disease activity was markedly attenuated in all rats treatedwith CsA alone. Vit D3 and certain of its synthetic analoguesadministered alone also tempered the autoimmune process, butto a lesser extent than did CsA. The effect of CsA alone wasso potent, that no additive or synergistic effects could bedemonstrated when CsA was administered in combination with VitD3. CONCLUSIONS.: Despite similar described immunomodulatory effects in vitro,CsA is clearly more effective than Vit D3 in preventing HgCl2autoimmune disease in BN rats. This suggests that there is adifference in the cellular targets of these two agents in vivo,and/or a difference in the potency with which HgCl2-triggeredimmune activation is suppressed. 相似文献
36.
The characteristics of 254 cadaveric kidneys were evaluated and the incidence of immediate function identified. The Belzer perfusate was used primarily (n = 140) and secondarily (n = 14) in combination with pulsatile machine perfusion. These two groups were compared with a previous group of kidneys machine-perfused with silica gel (cryoprecipitated human plasma). The incidence of immediate function of the group primarily perfused with Belzer perfusate was statistically significantly improved over that of the silica gel. The secondarily perfused Belzer group, "imported" kidneys previously preserved with simple cold storage, had notably longer periods of preservation and higher resistances on the machine. However, 100% of this group functioned immediately. Other findings in this study show that the Belzer perfusate allows for improved parenchymal function posttransplant, as noted by a more rapid clearance of serum creatinine posttransplant. When comparing the immediate function group with those suffering early dysfunction, there is a statistically significant increased resistance on the machine in the latter group. This allows for prediction of immediate function based on perfusion characteristics of the kidney. The Belzer perfusate, composed of metabolic substrates for high-energy phosphate production, improves the incidence of immediate function in machine-perfused kidneys, as well as improved qualitative function posttransplant. It also is effective as a "rescue" mechanism in previously simple cold-stored (ATP-depleted) kidneys. 相似文献
37.
29. Tagung der ?sterreichischen Gesellschaft für Chirurgie und Ihrer Assoziierten Fachgesellschaften Innsbruck, 2. bis 4. Juni 1988 Herausgeber: E. Bodner und G. Szinicz Abstracts
Benigne Erkrankungen des ?sophagogastralen überganges: Therapieversager-Korrekturm?glichkeiten 相似文献38.
A 70-year-old woman presented with anular and progressive intramyocardial calcification within a five-year period. She had become increasingly symptomatic with mitral regurgitation and coronary insufficiency during the same period. The subvalvular (mitral) calcified intramyocardial mass was found to be "grumous atherosclerosis." This was obliterated while the mitral valve was replaced with a prosthetic valve and the coronary arteries were bypassed x3. She is surviving and well four years postoperatively. 相似文献
39.
Functional analysis of the cag pathogenicity island in Helicobacter pylori isolates from patients with gastritis, peptic ulcer, and gastric cancer 总被引:9,自引:0,他引:9 下载免费PDF全文
Backert S Schwarz T Miehlke S Kirsch C Sommer C Kwok T Gerhard M Goebel UB Lehn N Koenig W Meyer TF 《Infection and immunity》2004,72(2):1043-1056
Helicobacter pylori is the causative agent of a variety of gastric diseases, but the clinical relevance of bacterial virulence factors is still controversial. Virulent strains carrying the cag pathogenicity island (cagPAI) are thought to be key players in disease development. Here, we have compared cagPAI-dependent in vitro responses in H. pylori isolates obtained from 75 patients with gastritis, peptic ulcer, and gastric cancer (n = 25 in each group). AGS gastric epithelial cells were infected with each strain and assayed for (i) CagA expression, (ii) translocation and tyrosine phosphorylation of CagA, (iii) c-Src inactivation, (iv) cortactin dephosphorylation, (v) induction of actin cytoskeletal rearrangements associated with cell elongation, (vi) induction of cellular motility, and (vii) secretion of interleukin-8. Interestingly, we found high but similar prevalences of all of these cagPAI-dependent host cell responses (ranging from 56 to 80%) among the various groups of patients. This study revealed CagA proteins with unique features, CagA subspecies of various sizes, and new functional properties for the phenotypic outcomes. We further showed that induction of AGS cell motility and elongation are two independent processes. Our data corroborate epidemiological studies, which indicate a significant association of cagPAI presence and functionality with histopathological findings in gastritis, peptic ulcer, and gastric cancer patients, thus emphasizing the importance of the cagPAI for the pathogenicity of H. pylori. Nevertheless, we found no significant association of the specific H. pylori-induced responses with any particular patient group. This may indicate that the determination of disease development is highly complex and involves multiple bacterial and/or host factors. 相似文献
40.
Marc A. Sommer Edward J. Tehovnik 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1997,116(2):229-249
The macaque frontal eye field (FEF) is involved in the generation of saccadic eye movements and fixations. To better understand
the role of the FEF, we reversibly inactivated a portion of it while a monkey made saccades and fixations in response to visual
stimuli. Lidocaine was infused into a FEF and neural inactivation was monitored with a nearby microelectrode. We used two
saccadic tasks. In the delay task, a target was presented and then extinguished, but the monkey was not allowed to make a
saccade to its location until a cue to move was given. In the step task, the monkey was allowed to look at a target as soon
as it appeared. During FEF inactivation, monkeys were severely impaired at making saccades to locations of extinguished contralateral
targets in the delay task. They were similarly impaired at making saccades to locations of contralateral targets in the step
task if the target was flashed for ≤100 ms, such that it was gone before the saccade was initiated. Deficits included increases
in saccadic latency, increases in saccadic error, and increases in the frequency of trials in which a saccade was not made.
We varied the initial fixation location and found that the impairment specifically affected contraversive saccades rather
than affecting all saccades made into head-centered contralateral space. Monkeys were impaired only slightly at making saccades
to contralateral targets in the step task if the target duration was 1000 ms, such that the target was present during the
saccade: latency increased, but increases in saccadic error were mild and increases in the frequency of trials in which a
saccade was not made were insignificant. During FEF inactivation there usually was a direct correlation between the latency
and the error of saccades made in response to contralateral targets. In the delay task, FEF inactivation increased the frequency
of making premature saccades to ipsilateral targets. FEF inactivation had inconsistent and mild effects on saccadic peak velocity.
FEF inactivation caused impairments in the ability to fixate lights steadily in contralateral space. FEF inactivation always
caused an ipsiversive deviation of the eyes in darkness. In summary, our results suggest that the FEF plays major roles in
(1) generating contraversive saccades to locations of extinguished or flashed targets, (2) maintaining contralateral fixations,
and (3) suppressing inappropriate ipsiversive saccades.
Received: 2 February 1996 / Accepted: 26 February 1997 相似文献