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11.
Leukotriene and prostaglandin production by mouse peritoneal macrophages was investigated. It could be shown that the tumour promoter 12-O-tetradecanoylphorbol-13-acetate initiated the release of prostaglandin E2 but had little effect on the release of leukotriene C4-like immunoreactivity. The divalent cation ionophore A 23187 at concentrations between 10–6 and 10–8 mol/l initiated prostaglandin as well as leukotriene release. This prostaglandin and leukotriene release could be modulated by drugs. Non-steroidal anti-inflammatory drugs including benoxaprofen inhibited prostaglandin release but simultaneously enhanced leukotriene production. The analgesics paracetamol and 4-methylaminoantipyrine had similar effects at high concentrations. The experimental compound BW 755 c inhibited prostaglandin and leukotriene production while the antithrombotic compound nafazatrom inhibited the production of leukotriene C4-like immunoreactivity but enhanced prostaglandin E2 production. Nordihydroguaiaretic acid inhibited prostaglandin and leukotriene production. The results show that the metabolism of arachidonic acid in macrophages via the cyclooxygenase or the lipoxygenase pathway is dependent on the stimulus applied. Both pathways can be inhibited conjointly or selectively by drugs. Our results do not provide evidence that differences in anti-inflammatory activity claimed for some of the drugs tested can be explained by differential inhibition of either pathway. The experimental system described may be used for assessing the potency of drugs to inhibit the lipoxygenase and the cyclooxygenase pathway of arachidonic acid metabolism. 相似文献
12.
Datenschutz innerhalb des länderübergreifenden Deutschen Zentralregisters für kindliche Hörstörungen
Zusammenfassung
Das Deutsche Zentralregister für kindliche H?rst?rungen (DZH) verarbeitet bundesweit Daten von verschiedenen audiologischen
Einrichtungen. Die Bew?ltigung der anfallenden Datenmengen, die nachfolgende Datenverwaltung und -analyse erfordern neben
einer differenzierten und kontrollierbaren Verarbeitung ein H?chstma? an Datensicherheit. Vor allem die l?nderübergreifende
Struktur eines Registers erfordert schon bei der Planung engste Zusammenarbeit mit dem zust?ndigen Landesdatenschutzbeauftragten
und auch mit den Landesdatenschutzbeauftragten anderer beteiligter Bundesl?nder. Am Beispiel des DZH wird demonstriert, wie
eine kooperative Zusammenarbeit pragmatisch realisiert werden kann. Besonderheiten bei der Datenerhebung, Datentransfer, Speicherung
und L?schung von Daten, technische Datenschutzma?nahmen, Sicherstellung von Anonymit?t durch Codierungsstrategien, Duplikatsprüfung,
Datentrennung und automatisierte Datenauswertung werden an Beispielen erl?utert.
Eingegangen am 13. August 1997 Angenommen am 18. Dezember 1997 相似文献
13.
Ute Finckh-Krämer Maria-Elisabeth Spormann-Lagodzinski K. Nubel M. Hess M. Gross 《HNO》1998,46(6):598-602
Zusammenfassung
Das Deutsche Zentralregister (DZH) für kindliche H?rst?rungen hat seit 1994 Patientendatens?tze von 1500 Kindern erfa?t und
kann mittlerweile u.a. Aussagen und Ergebnisse zum Diagnosezeitpunkt persistierender kindlicher H?rst?rungen in der Bundesrepublik
Deutschland vorlegen. Nach wie vor ist das mittlere Alter bei der Diagnose persistierender kindlicher H?rst?rungen sehr hoch.
Das Diagnosealter korreliert stark mit dem Grad der H?rst?rung, d.h. an Taubheit grenzende und hochgradige H?rst?rungen werden
deutlich früher diagnostiziert als leichte und mittlere. So werden leichte H?rst?rungen im Durchschnitt erst mit 6;2 Jahren
diagnostiziert, mittlere mit 4;4 Jahren, hochgradige mit 2;5 Jahren und an Taubheit grenzende mit 1;9 Jahren. Dies entspricht
den Ergebnissen bereits vorliegender regionaler deutscher Studien [1–2]. Aus anderen europ?ischen L?nderen sind zumindest
regional deutlich frühere Diagnosezeitpunkte bekannt [3–5]. Bei 36% der im DZH erfa?ten Kinder liegt zwischen dem ersten Verdacht
auf Vorliegen einer persistierenden kindlichen H?rst?rung und der Sicherstellung der Diagnose ein Jahr und mehr.
Eingegangen am 23. Dezember 1997 Angenommen am 16. April 1998 相似文献
14.
15.
Hannah Reemtsma Cora M. Holicki Christine Fast Felicitas Bergmann Martin Eiden Martin H. Groschup Ute Ziegler 《Viruses》2022,14(6)
West Nile virus (WNV) is an emerging infectious pathogen circulating between mosquitoes and birds but also infecting mammals. WNV has become autochthonous in Germany, causing striking mortality rates in avifauna and occasional diseases in humans and horses. We therefore wanted to assess the possible role of free-ranging poultry in the WNV transmission cycle and infected 15 goslings with WNV lineage 2 (German isolate). The geese were monitored daily and sampled regularly to determine viremia, viral shedding, and antibody development by molecular and serological methods. Geese were euthanized at various time points post-infection (pi). All infected geese developed variable degrees of viremia from day 1 to day 10 (maximum) and actively shed virus from days 2 to 7 post-infection. Depending on the time of death, the WN viral genome was detected in all examined tissue samples in at least one individual by RT-qPCR and viable virus was even re-isolated, except for in the liver. Pathomorphological lesions as well as immunohistochemically detectable viral antigens were found mainly in the brain. Furthermore, all of the geese seroconverted 6 days pi at the latest. In conclusion, geese are presumably not functioning as important amplifying hosts but are suitable sentinel animals for WNV surveillance. 相似文献
16.
Cardioprotective effects of the serine protease inhibitor aprotinin after regional ischemia and reperfusion on the beating heart 总被引:3,自引:0,他引:3
Pruefer D Buerke U Khalil M Dahm M Darius H Oelert H Buerke M 《The Journal of thoracic and cardiovascular surgery》2002,124(5):942-949
OBJECTIVE: Early coronary reperfusion of the ischemic myocardium is a desired therapeutic goal to preserve myocardium. However, reperfusion itself contributes to an additional myocardial injury (ie, reperfusion injury), which has been attributed to neutrophil infiltration with subsequent release of proteases and oxygen-derived radicals. We studied the effects of the serine protease inhibitor aprotinin (Trasylol) on myocardial ischemia and reperfusion in a rat model. METHODS: The effects of aprotinin (5000 and 20,000 U/kg) were examined in vivo in a rat model of regional myocardial ischemia (20 minutes) and long-term reperfusion (24 hours). Cardioprotecive effects were determined by means of measurement of creatine kinase and myeloperoxidase activity within the myocardium, as well as histochemical analysis. RESULTS: Aprotinin (20,000 U/kg) administrated 2 minutes before reperfusion significantly attenuated myocardial injury expressed as creatine kinase washout compared with that seen in vehicle-treated rats (65 +/- 25 vs 585 +/- 98 creatine kinase difference in units per 100 mg, P <.01). Administration of 5000 U/kg of the protease inhibitor resulted in partial inhibition of myocardial reperfusion injury. Moreover, cardiac myeloperoxidase activity in the ischemic myocardium, a marker of neutrophil accumulation, was significantly reduced after aprotinin treatment. Histologic analysis of the reperfused myocardium demonstrated reduced polymorphonuclear leukocyte infiltration and reduced tissue injury. Furthermore, aprotinin treatment resulted in decreased induction of cardiac myocyte apoptosis compared with that seen in vehicle-treated rats. CONCLUSIONS: Inhibition of serine proteases with aprotinin appears to be an effective means of preserving ischemic myocardium from reperfusion injury, even after 24 hours of reperfusion. Aprotinin might exert cardioprotection through inhibition of polymorphonuclear leukocyte-induced myocardial injury and inhibition of reperfusion-induced apoptosis of cardiac myocytes. 相似文献
17.
Olena Andrukhova Jessica Bayer Christiane Schüler Ute Zeitz Sathish K Murali Sibel Ada Jose M Alvarez‐Pez Alina Smorodchenko Reinhold G Erben 《Journal of bone and mineral research》2017,32(10):2049-2061
Fibroblast growth factor‐23 (FGF23) is a bone‐derived hormone regulating vitamin D hormone production and renal handling of minerals by signaling through an FGF receptor/αKlotho (Klotho) receptor complex. Whether Klotho has FGF23‐independent effects on mineral homeostasis is a controversial issue. Here, we aimed to shed more light on this controversy by comparing male and female triple knockout mice with simultaneous deficiency in Fgf23 and Klotho and a nonfunctioning vitamin D receptor (VDR) (Fgf23/Klotho/VDR) with double (Fgf23/VDR, Klotho/VDR, and Fgf23/Klotho) and single Fgf23, Klotho, and VDR mutants. As expected, 4‐week‐old Fgf23, Klotho, and Fgf23/Klotho knockout mice were hypercalcemic and hyperphosphatemic, whereas VDR, Fgf23/VDR, and Klotho/VDR mice on rescue diet were normocalcemic and normophosphatemic. Serum levels of calcium, phosphate, and sodium did not differ between 4‐week‐old triple Fgf23/Klotho/VDR and double Fgf23/VDR or Klotho/VDR knockout mice. Notably, 3‐month‐old Fgf23/Klotho/VDR triple knockout mice were indistinguishable from double Fgf23/VDR and Klotho/VDR compound mutants in terms of serum calcium, serum phosphate, serum sodium, and serum PTH, as well as urinary calcium and sodium excretion. Protein expression analysis revealed increased membrane abundance of sodium‐phosphate co‐transporter 2a (NaPi‐2a), and decreased expression of sodium‐chloride co‐transporter (NCC) and transient receptor potential cation channel subfamily V member 5 (TRPV5) in Fgf23/Klotho/VDR, Fgf23/VDR, and Klotho/VDR mice, relative to wild‐type and VDR mice, but no differences between triple and double knockouts. Further, ex vivo treatment of live kidney slices isolated from wild‐type and Klotho/VDR mice with soluble Klotho did not induce changes in intracellular phosphate, calcium or sodium accumulation assessed by two‐photon microscopy. In conclusion, our data suggest that the main physiological function of Klotho for mineral homeostasis in vivo is its role as co‐receptor mediating Fgf23 action. © 2017 American Society for Bone and Mineral Research. 相似文献
18.
Ute Gawlick 《American journal of surgery》2008,196(6):851-856
Background
In breast cancer staging, the need for intraoperative sentinel lymph (SLN) evaluation is not well established. This study compares intraoperative use of touch preparation (TP), frozen section (FS), and factors that may influence the selective use of intraoperative SLN analysis.Methods
Breast cancer patients (1998-2007) undergoing SLN evaluation were retrospectively reviewed.Results
Of 205 SLN procedures, 157 cases underwent intraoperative evaluation, 43% (FS) and 57% (TP) with positive pathology in 21% and 20%, respectively. The false negative case rate was 16% for TP versus 12% for FS. Of T1, low-grade tumors, 9% were intraoperatively positive, versus 43% of T2-3, moderate- to high-grade tumors (P = .006). Additional positive axillary nodes were found in 43% of the higher risk patients versus 0% in the lower risk groups.Conclusions
Both TP and FS are accurate for intraoperative SLN evaluation and can be selectively applied to breast cancer staging in low- and high-risk groups. 相似文献19.
Schilling D Schlemmer HP Wagner PH Böttcher P Merseburger AS Aschoff P Bares R Pfannenberg C Ganswindt U Corvin S Stenzl A 《BJU international》2008,102(4):446-451
OBJECTIVES
To evaluate the potential of 11C‐choline‐positron emission tomography (PET)/computed tomography (CT) for planning surgery in patients with prostate cancer and prostate‐specific antigen (PSA) relapse after treatment with curative intent.PATIENTS AND METHODS
We retrospectively reviewed the charts of 10 patients with PSA recurrence after either external beam radiation (two) or radical retropubic prostatectomy (eight) for prostate cancer, and who had a laparoscopic lymphadenectomy for suspicious lymph nodes detected on 11C‐choline‐PET/CT. The histological results and PET/CT findings were compared.RESULTS
In all, 22 suspicious lymph nodes were found on PET/CT, and 14 on conventional CT or magnetic resonance imaging. Comparing the conventional imaging showed concordance in 13 lymph nodes. Three of the 10 patients had no metastatic lymph node disease on definitive histology. The mean (sd ) PSA level for these patients was 1.0 (0.4) ng/mL, whereas that in patients with lymph node metastases was 15.1 (9.2) ng/mL (statistically significant difference, P < 0.05). The positive predictive value was seven of 10. All of the patients initially regressed, with PSA increases after lymphadenectomy. Two of the patients are being managed by watchful waiting, two had radiotherapy of the prostate fossa and two had chemotherapy with docetaxel. Four patients were treated by hormone‐deprivation therapy. After a mean (sd ) follow up of 11 (7) months, one patient died, one has PSA progression, but none of those with negative histology has clinical signs of local recurrence.CONCLUSIONS
11C‐choline‐PET is a valuable tool for detecting recurrent prostate cancer, but the limited positive predictive value should lead to a critical interpretation of the results. 相似文献20.
Molecular and functional expression of voltage-operated calcium channels during osteogenic differentiation of human mesenchymal stem cells. 总被引:1,自引:0,他引:1
Ihor Zahanich Eva M Graf Jürgen F Heubach Ute Hempel Sabine Boxberger Ursula Ravens 《Journal of bone and mineral research》2005,20(9):1637-1646
We used the patch-clamp technique and RT-PCR to study the molecular and functional expression of VOCCs in undifferentiated hMSCs and in cells undergoing osteogenic differentiation. L-type Ca2+ channel blocker nifedipine did not influence alkaline phosphatase activity, calcium, and phosphate accumulation of hMSCs during osteogenic differentiation. This study suggests that osteogenic differentiation of hMSCs does not require L-type Ca2+ channel function. INTRODUCTION: During osteogenic differentiation, mesenchymal stem cells from human bone marrow (hMSCs) must adopt the calcium handling of terminally differentiated osteoblasts. There is evidence that voltage-operated calcium channels (VOCCs), including L-type calcium channels, are involved in regulation of osteoblast function. We therefore studied whether VOCCs play a critical role during osteogenic differentiation of hMSCs. MATERIALS AND METHODS: Osteogenic differentiation was induced in hMSCs cultured in maintenance medium (MM) by addition of ascorbate, beta-glycerophosphate, and dexamethasone (ODM) and was assessed by measuring alkaline phosphatase activity, expression of osteopontin, osteoprotegerin, RANKL, and mineralization. Expression of Ca2+ channel alpha1 subunits was shown by semiquantitative or single cell RT-PCR. Voltage-activated calcium currents of hMSCs were measured with the whole cell voltage-clamp technique. RESULTS: mRNA for the pore-forming alpha1C and alpha1G subunits of the L-type and T-type Ca2+ channels, respectively, was found in comparable amounts in cells cultured in MM or ODM. The limitation of L-type Ca2+ currents to a subpopulation of hMSCs was confirmed by single cell RT-PCR, where mRNA for the alpha1C subunits was detectable in only 50% of the cells cultured in MM. Dihydropyridine-sensitive L-type Ca2+ currents were found in 13% of cells cultured in MM and in 12% of the cells cultured in ODM. Under MM and ODM culture conditions, the cells positive for L-type Ca2+ currents were significantly larger than cells without Ca2+ currents as deduced from membrane capacitance; thus, current densities were comparable. Addition of the L-type Ca2+ channel blocker nifedipine to the culture media did not influence alkaline phosphatase activity and the extent of mineralization. CONCLUSION: These results suggest that, in the majority of hMSCs, Ca2+ entry through the plasma membrane is mediated by some channels other than VOCCs, and blockade of the L-type Ca2+ channels does not affect early osteogenic differentiation of hMSCs. 相似文献