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1.
There is increasing public interest in natural or herbal-based healthcare products. This trend is not only visible in supermarkets and dental practices, but also in the scientific world. An improving number of clinical trials are being conducted to validate the claims made about these products in regards to periodontal health. Among single component preparations, Aloe vera and green tea are the most studied natural ingredients. Concerning polyherbal mixtures, triphala has garnered great interest. The effects of these natural products on periodontal health is encouraging, with almost all studies showing an inhibitory effect on plaque accumulation and an improvement in gingival health. However, more studies are needed to be able to design clinical guidelines to guide the use of these natural products in periodontal practice. For most of these products, few studies are available and, moreover, the available studies are limited in duration, the number of participants, and the specific composition of the natural product is often not described in detail. 相似文献
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Cytochrome P450 3A4 and P-glycoprotein Activity and Assimilation of Tacrolimus in Transplant Patients with Persistent Diarrhea 总被引:2,自引:0,他引:2
Wim Lemahieu Bart Maes Kristin Verbeke Paul Rutgeerts Karel Geboes Yves Vanrenterghem 《American journal of transplantation》2005,5(6):1383-1391
Renal transplant recipients suffering from persistent diarrhea have been repeatedly reported to have increased tacrolimus (Tac) trough levels. This study aimed to explore this phenomenon in detail in 15 renal transplant recipients with diarrhea, whose immunosuppression consisted of corticosteroids, mofetil mycophenolate and Tac. Both hepatic and intestinal CYP3A4 and PGP activity, important determinants of Tac bioavailability, were assessed, together with global CYP activity and investigations for gastrointestinal infection, function and morphology. Global CYP, CYP3A4, PGP and trough/dose levels of Tac were compared with diarrhea-free controls. In addition, a pharmacokinetic study of Tac was performed in 11 patients affected by diarrhea versus 9 controls. As expected, diarrhea was associated with increased Tac trough levels. An even stronger, significant increase of dose-normalized Tac levels was observed between 90 and 360 min after Tac intake. Time to peak concentration and drug half-life, however, were not altered. In addition, a concomitant decrease (+/-50%) of intestinal PGP activity was noticed in patients with diarrhea. For global CYP, CYP3A4 and hepatic PGP activity no such differences were noted. This pattern was not influenced by the specific cause of diarrhea. These data strongly suggest that persistent diarrhea is associated with an increased oral bioavailability of Tac. 相似文献
4.
Wim Van Biesen Raymond Vanholder Nic Veys Francis Verbeke Joris Delanghe Dirk De Bacquer Norbert Lameire 《Nephrology, dialysis, transplantation》2006,21(1):77-83
BACKGROUND: In an attempt to reduce late referral and to improve the care of patients with chronic kidney disease (CKD), different organizations have issued guidelines on when to refer patients to the nephrologist. Most suggest referral of patients with a GFR below 60 ml/min/1.73 m2, and demand referral if the GFR is below 30 ml/min/1.73 m2. It is recommended to use the abbreviated MDRD equation to estimate GFR. This formula is, however, sensitive to the creatinine assay methodology. In addition, the impact of the implementation of such guidelines on the nephrology practice has never been evaluated. This study (i) identifies the true burden of CKD in a population and simulates the effects of a 100% implementation of the guidelines on the nephrology work load, and (ii) evaluates the validity of the estimated GFR using the abbreviated MDRD formula when routinely provided. METHODS: Different laboratories (both hospital and private) in our region were asked to report on all the serum creatinine values performed during the first week of December 2004. If patients had more than one determination, only the lowest serum creatinine value was retained. Patients already known to a nephrology unit were not included. GFR was calculated using the abbreviated MDRD, using the serum creatinine as reported by these laboratories, or after correction to the MDRD-standard using different published equations. RESULTS: 20,108 patients, with a mean age of 53.4+/-16.2 years, 48% females, had at least one serum creatinine determination in the observation period. According to the K/DOQI CKD classification, 20.2, 1.6 and 0.8% of females and 13.3, 1.6 and 0.6% of males were in stage 3, 4 and 5, respectively, when the abbreviated MDRD formula was used with the serum creatinine value as reported by the laboratories. Important differences in classifications were obtained when the different correction formulae for creatinine were applied. According to the current recommendations, this would lead to a mandatory referral of 1650-2400 CKD stage 4 patients per 100 000 inhabitants and a suggested referral of another 4100-15 360 CKD stage 3 patients per 100,000 inhabitants to a nephrology unit. CONCLUSION: Implementation of the current guidelines for referral of CKD patients to nephrologists would lead to an overload of the nephrology care capacities. Large differences in estimated GFRs with different corrections for serum creatinine are observed, resulting in important CKD classification differences. Standardization of serum creatinine assays is mandatory before guidelines, and especially the routine provision of the estimated GFR by the abbreviated MDRD formula, can be implemented in clinical practice. 相似文献
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6.
Ferry Verbaan Inger van Dam Yoshinubu Takakura Mitsuru Hashida Wim Hennink Gert Storm Christien Oussoren 《European journal of pharmaceutical sciences》2003,20(4-5):419-427
The objective of this study was to assess the in vivo fate of poly(2-(dimethylamino)ethyl methacrylate) (pDMAEMA)-based polyplexes after intravenous administration into mice. Circulation kinetics and tissue distribution in terms of plasmid localization and transfection efficiency were assessed. To gain more insight into the observed biodistribution and gene expression profile, the interaction of pDMAEMA-based polyplexes with blood components (erythrocytes and albumin) was investigated in vitro. In the case of i.v. injection of positively charged polyplexes at a dose of 30 microg DNA most of the radioactivity was found in the lungs and the liver 60 min after injection. In the case of pDMAEMA/DNA polyplexes with a negative charge, uptake occurred mainly by the liver. Administration of positively charged complexes at a 30 microg DNA dose resulted in reporter gene expression primarily in the lungs. Injection of negatively charged complexes and naked plasmid did not result in luciferase expression in any of the organs examined. In vitro turbidity experiments showed the induction of a charge dependent aggregation process upon addition of albumin to the polyplexes pointing out to the involvement of aggregate formation in the dominant lung uptake of the positively charged polyplexes. Also, incubations of polyplexes after pre-incubation with a physiological concentration of albumin with washed erythrocytes confirmed that polyplexes induce the formation of extremely large structures. This paper underlines the need for the design of systems with reduced interaction with blood components to promote the delivery of DNA to target tissues outside the lungs. 相似文献
7.
Julli?tte E M van Eerd Huub J J M Rennen Wim J G Oyen Thomas D Harris D Scott Edwards Frans H M Corstens Otto C Boerman 《Journal of nuclear medicine》2004,45(10):1747-1753
Radiolabeled chemotactic peptides have been studied for their applicability to the visualization of infectious and inflammatory foci. Because a radiolabeled leukotriene B4 (LTB4) antagonist allowed visualization of intramuscular E. coli abscesses in rabbits within a few hours after injection, we decided to test the imaging characteristics of this agent in a more clinically relevant model of pulmonary aspergillosis. The pharmacokinetics and imaging characteristics of the 111In-labeled LTB4 antagonist DPC11870 were studied in New Zealand White rabbits with experimental pulmonary aspergillosis infection. The imaging characteristics of 111In-DPC11870 were compared with those of 67Ga-citrate, a radiopharmaceutical commonly used to detect pulmonary infections in patients. METHODS: Pulmonary aspergillosis was induced in the left lung of rabbits by intratracheal inoculation of 1 x 10(8) conidia of Aspergillus fumigatus. Three days after the inoculation, the rabbits received 111In-DPC11870 or 67Ga-citrate intravenously. Images were acquired at several time points up to 24 h after injection. RESULTS: Pulmonary aspergillosis was visualized with both agents. Images acquired after injection of 111In-DPC11870 showed uptake in the pulmonary lesions from 6 h after injection. Because of accumulation at the site of infection and clearance from the background, the images improved with time. Region-of-interest analysis at 24 h after injection revealed infected lung-to-normal lung ratios of 5.0 +/- 1.5 for 111In-DPC11870 and 2.9 +/- 0.6 for 67Ga-citrate. CONCLUSION: The radiolabeled LTB4 antagonist DPC11870 clearly delineated experimentally induced pulmonary aspergillosis in rabbits. Images acquired at 24 h after injection of 111In-DPC11870 were superior to those obtained after injection of 67Ga-citrate. 相似文献
8.
A 79-year-old man was referred to emergency department for vagueabdominal pain. In the past, the patient had cardiac arrhythmiasnecessitating a pacemaker placement. On admission, the patienthad a normal ausculation and the abdomen examination was unremarkable.Postero-anterior chest radiograph revealed normal cardiac sizeand a small left pleural effusion. 相似文献
9.
The use of a new hydrophilic polymer, Kollicoat IR, in the formulation of solid dispersions of Itraconazole. 总被引:1,自引:0,他引:1
Sandrien Janssens Hector Novoa de Armas Jean Paul Remon Guy Van den Mooter 《European journal of pharmaceutical sciences》2007,30(3-4):288-294
Kollicoat IR, a new pharmaceutical excipient developed as a coating polymer for instant release tablets, was evaluated as a carrier in solid dispersions of Itraconazole. The solid dispersions were prepared by hot stage extrusion. Modulated temperature differential scanning calorimetry and X-ray powder diffraction were used to evaluate the miscibility of the drug and the carrier. The pharmaceutical performance was evaluated by dissolution experiments, performed in simulated gastric fluid without pepsin (SGF(sp)). In the X-ray diffractograms no Itraconazole peaks were visible; the polymer on the other hand appeared to be semi-crystalline. Moreover, its crystallinity increased during the extrusion process due to exposure to heat and shear forces. Modulated temperature differential scanning calorimetry analysis showed that the drug and the polymer formed a two phase system. Separate clusters of glassy Itraconazole were present for drug loads of 40% or higher, indicating further phase separation. Dissolution measurements demonstrated a significantly increased dissolution rate for the solid dispersions compared to physical mixtures. Interestingly the physical mixture made up of glassy Itraconazole and Kollicoat IR (20/80, w/w) showed a dissolution rate and maximum that was much higher than that of the physical mixture made up of crystalline Itraconazole and that of pure glassy Itraconazole. The results of this study show that Kollicoat IR is a promising excipient for the formulation of solid dispersions of Itraconazole prepared by hot stage extrusion. 相似文献
10.
Zusammenfassung Bei Nachweis von rechtskardialen Thromben handelt es sich in den meisten F?llen um sogenannte ,,Transit-Thromben`` aus dem
peripheren Venensystem, die nur kurz im rechten Herzen verweilen. Die Inzidenz von transthorakal echokardiographisch nachgewiesenen
,,Transit-Thromben`` bei Patienten mit Lungenembolie liegt bei etwa 3 – 4%. Unbehandelt ist die Letalit?tsrate dieser Patienten
jedoch auf Grund der hohen Rate konsekutiver fulminanter Lungenembolien sehr hoch (30 – 40%). Bis vor einigen Jahren galt
die operative Embolektomie als das Therapieverfahren der Wahl, das jedoch heute zunehmend durch die systemische, intraven?se
Lysetherapie als Alternative ersetzt wird.
Im Zeitraum von 1/94 bis 12/95 wurden in unserer Klinik 66 Patienten mit nachgewiesener Lungenembolie behandelt. Bei sieben
dieser Patienten mit schwerer oder fulminanter Lungenembolie (10,6%; 5 M?nner, 55 – 74 Jahre alt) fanden sich rechtskardiale
Thromben, die in allen F?llen mittels transthorakaler/ trans?sophagealer Echokardiographie (TEE) diagnostiziert wurden. In
sechs F?llen sahen wir extrem mobile, wurmf?rmige Thromben im rechten Atrium, die zum Teil diastolisch tief in den rechten
Ventrikel prolabierten. Bei einem Patienten waren die Thromben im rechten Ventrikel lokalisiert und fielen ventrikel-systolisch
in den rechtsventrikul?ren Ausflu?trakt. In drei F?llen lie?en sich mittels TEE auch Thromben in der rechten Pulmonalarterie
darstellen. Fünf Patienten wurden unmittelbar im Anschlu? an die TEE-Untersuchung ohne weitere angiographische Diagnostik
mit einer systemischen, intraven?sen Lysetherapie mit 100 mg front-loaded rt-PA über 90 Minuten behandelt. Ein prim?r reanimationspflichtiger
Patient erhielt als ,,Ultima Ratio`` 100 mg rt-PA als Bolus, eine weitere Patientin 50 mg rt-PA als Bolus gefolgt von 50 mg
über 2 Stunden. Bei allen Patienten stabilisierte sich der h?modynamische Zustand innerhalb kürzester Zeit. In sechs F?llen
konnte mittels TEE und einmal mittels transthorakaler Echokardiographie innerhalb von 15 Stunden die komplette Aufl?sung der
rechtskardialen Thromben dokumentiert werden. Bei einem Patienten kam es zu einer intracerebralen Blutung und ein Patient
verstarb nach 10 Tagen an den Folgen der protrahierten Reanimation mit hypoxischem Hirnschaden.
Mittels TTE/TEE lassen sich rechtskardiale Transitthromben als koinzidenter Befund bei Patienten mit klinischen Hinweisen
für eine fulminante Lungenembolie gut diagnostizieren sowie der Therapieerfolg verfolgen. In diesen F?llen ist die sofortige
systemische Lysetherapie ohne weitere bildgebende Diagnostik durchzuführen, um einer weiteren Verschlechterung der klinischen
Situation in Folge Transports und Umlagerung des Patienten mit der Gefahr des Abschwemmens des Transitthrombus vorzubeugen.
Eingegangen: 15. Mai 1996 Akzeptiert: 23. Oktober 1996 相似文献