全文获取类型
收费全文 | 28510篇 |
免费 | 1236篇 |
国内免费 | 59篇 |
专业分类
耳鼻咽喉 | 425篇 |
儿科学 | 778篇 |
妇产科学 | 551篇 |
基础医学 | 4349篇 |
口腔科学 | 660篇 |
临床医学 | 2308篇 |
内科学 | 5349篇 |
皮肤病学 | 872篇 |
神经病学 | 2765篇 |
特种医学 | 1660篇 |
外国民族医学 | 23篇 |
外科学 | 4404篇 |
综合类 | 94篇 |
一般理论 | 10篇 |
预防医学 | 1367篇 |
眼科学 | 528篇 |
药学 | 2067篇 |
中国医学 | 30篇 |
肿瘤学 | 1565篇 |
出版年
2023年 | 175篇 |
2022年 | 248篇 |
2021年 | 516篇 |
2020年 | 308篇 |
2019年 | 393篇 |
2018年 | 607篇 |
2017年 | 478篇 |
2016年 | 710篇 |
2015年 | 777篇 |
2014年 | 845篇 |
2013年 | 1074篇 |
2012年 | 1653篇 |
2011年 | 1597篇 |
2010年 | 924篇 |
2009年 | 769篇 |
2008年 | 1363篇 |
2007年 | 1374篇 |
2006年 | 1332篇 |
2005年 | 1294篇 |
2004年 | 1152篇 |
2003年 | 1110篇 |
2002年 | 999篇 |
2001年 | 803篇 |
2000年 | 894篇 |
1999年 | 734篇 |
1998年 | 234篇 |
1997年 | 171篇 |
1996年 | 136篇 |
1992年 | 342篇 |
1991年 | 371篇 |
1990年 | 355篇 |
1989年 | 319篇 |
1988年 | 269篇 |
1987年 | 274篇 |
1986年 | 234篇 |
1985年 | 239篇 |
1984年 | 185篇 |
1983年 | 122篇 |
1982年 | 118篇 |
1979年 | 196篇 |
1978年 | 136篇 |
1977年 | 123篇 |
1975年 | 154篇 |
1974年 | 134篇 |
1973年 | 157篇 |
1972年 | 143篇 |
1971年 | 129篇 |
1970年 | 134篇 |
1969年 | 125篇 |
1967年 | 120篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
G. Nikkhah J. C. Tonn O. Hoffmann H. -P. Kraemer J. L. Darling W. Schachenmayr R. Schönmayr 《Journal of neuro-oncology》1992,13(1):13-24
In this study we assessed the influence of patient- and drug-specific parameters in the short-term MTT-chemosensitivity assay in 150 primary cell cultures derived from human brain tumors. In 45 patients the MTT assay was directly compared with the CFA (Colony Forming Assay). Resistance was 10-20% higher in the MTT assay than in the CFA, but there was a good agreement in both assays, that more malignant gliomas had a higher in vitro chemosensitivity against ACNU and BCNU. Overall the results demonstrate, that there is no uniform correlation between the in vitro chemosensitivity and the histopathological classification of the tumors, which corresponds well to the clinical situation. On the basis of this study we suggest prospective clinical trials with the MTT assay in human brain tumors. 相似文献
72.
Summary The pharmacokinetics of isradipine, a calcium-channel blocker, have been studied in eight patients on chronic haemodialysis. A single oral dose of 5 mg was administered on both a non-haemodialysis and a haemodialysis day and the plasma concentrations of isradipine were analyzed.The mean cmax, tmax, AUC, and t1/2 in plasma on the non-haemodialysis day were 5.2 ng·ml–1, 1.4 h, 23.8 ng·h·ml–1, and 3.1 h, respectively. The dialysis clearance of isradipine was negligible (5.0 ml·min–1).The t1/2 values during haemodialysis were not significantly different from those observed during the same period post dose on the non-haemodialysis day. The study demonstrates that supplemental doses of isradipine are not necessary in these patients since isradipine is not significantly removed by haemodialysis. 相似文献
73.
M Zürcher I Schipper G Schüpfer P Senn 《Klinische Monatsbl?tter für Augenheilkunde》1992,200(5):338-342
In the period between September 1990 and July 1991, 35 patients (46 eyes) were treated with the Excimer Laser. In 25 patients (34 eyes), a Myopia-Laser-Shaping was performed, one patient was treated for both myopia and astigmatism. In eight patients (10 eyes) correction of astigmatism was carried out. Two patients with recurrent erosions and one patient with superficial scarring of the cornea were treated. The authors review their initial experience with the Excimer Laser. The decision to initiate treatment must not be undertaken lightly, because the possibility of serious complications may not be neglected. This method shows promise in selected patients with light to medium degrees of myopia. In cases of severe myopia, our experience is encouraging. Subjectively, the patients are satisfied with the results, which do not fall short of their expectations. Further research and clinical experience in this area is urgently required. 相似文献
74.
Das ambulante Operieren bringt neben finanzieller Entlastung der Kostenträger zweifelsohne eine Reihe von Vorteilen, aber auch Nachteile für die Patienten mit sich. Neben intensiven Anstrengungen zur Qualitätssicherung muss insbesondere die Diskussion über die Auswahl geeigneter Patienten für geeignete Eingriffe intensiv und kontinuierlich geführt werden. Dem Trend, das Spektrum ambulant durchgeführter Eingriffe auf ein immer stärker risikotragendes Patientengut auszudehnen, muss insgesamt zunächst mit Skepsis begegnet werden. Auch wenn mit den Fortschritten der Operationstechniken das operative Zugangstrauma erheblich reduziert werden kann und moderne Anästhesieverfahren eine sehr gute Steuerung der Patienten erlauben, stellt die Beherrschung der Komplikationen und Probleme der postoperativen Phase umso mehr besondere Herausforderungen sowohl an die ambulant operierenden Ärzte, Anästhesisten und Chirurgen als auch an die Patienten und mitbetreuenden Angehörigen. 相似文献
75.
Abstract
Background: In recent years, biomaterials are being found and frequently utilized in bone defects. They have also gained significant precedence
in hand surgery.
Objectives: The respective requirements for such replacement material will be cited and acknowledged in this article. The individual material
groups will also be referred to in this review. An introduction to some of the customary bone replacement materials will be
cited and concluded with a corresponding recommendation.
Conclusion: The implantation of autologous cancellous bone is still regarded today as the “gold standard”. Nevertheless, the usage of
bone replacement material can be an enormous advantage in certain indications.
The original article can be found online at
There was an error in the author’s affiliation and the address for correspondence was incomplete. Please note the correct
institution and complete address:
Department of Orthopedics and Traumatology, Hand-, Foot- and Reconstructive Surgery, Kreiskrankenhaus Gummersbach GmbH, Germany.
Alexander von Friesen, MD Department of Orthopedics and Traumatology, Hand-, Foot- and Reconstructive Surgery Kreiskrankenhaus
Gummersbach GmbH Wilhelm-Breckow-Allee 20 51643 Gummersbach Germany Phone (+49/2261) 171-575, Fax -449 e-mail: Friesen@kkh-gummersbach.de 相似文献
76.
Bernhard Z?llner Heinz-Hubert Feucht Martina Sterneck Hansj?rg Sch?fer Xavier Rogiers Lutz Fischer 《Liver transplantation》2006,12(8):1283-1289
Hepatitis B virus (HBV) DNA is detectable in a number of liver transplant candidates who are negative for hepatitis B surface antigen (HBsAg). After liver transplantation (LT), such patients may have molecular and/or serologic evidence of HBV replication. However, clinical disease from reactivation of occult HBV infection after LT has not been described. We report a patient who underwent LT for cryptogenic cirrhosis and had to be retransplanted twice for hepatic artery thrombosis. The patient was negative for HBsAg and positive for anti-hepatitis B core (HBc) and anti-HBs before all LT procedures and developed acute hepatitis B shortly after receiving the third graft. The HBV strain isolated at that time exhibited an unusual in frame insertion of a CAG motif within the HBV polymerase (HBV(INS+)). HBV(INS+) was detected retrospectively as a minor species in pretransplantation sera and the explanted native liver by insertion-specific polymerase chain reaction. This case in an occult HBV carrier shows that clinically apparent, endogenous reinfection of the graft may occur with minor HBV variants that are not detectable in pretransplantation samples by standard diagnostic procedures. This has implications for the analysis of sources of acute hepatitis B in patients after LT and possibly for consideration of antiviral prophylaxis in anti-HBc/anti-HBs/HBV DNA-positive patients. 相似文献
77.
Florian Kronenberg 《Journal of renal nutrition》2005,15(2):195-203
Patients with nephrotic syndrome (NS) have one of the most pronounced secondary changes in lipoprotein metabolism known, and the magnitude of the changes correlates with the severity of the disease. These changes are of a quantitative as well as a qualitative nature. All apolipoprotein B (apo B)-containing lipoproteins, such as very-low-density lipoproteins (VLDL), intermediate-density lipoproteins (IDL), low-density lipoproteins (LDL), and lipoprotein(a) [Lp(a)], are elevated in nephrotic syndrome. High-density lipoproteins (HDL) are reported to be unchanged or reduced. In addition to these quantitative changes, the lipoprotein composition is markedly changed, with a higher ratio of cholesterol to triglycerides in the apo B-containing lipoproteins and an increase in the proportion of cholesterol, cholesterol ester, and phospholipids compared with proteins. Also apolipoproteins show major changes, with an increase in apolipoprotein A-I, A-IV, B, C, and E. Particularly the changes in apo C-II, which is an activator of the enzyme lipoprotein lipase (LPL), and apo C-III, an inhibitor of LPL, with an increase of the C-III to C-II ratio, might contribute to the impaired lipoprotein catabolism in NS. The mechanisms for these changes in lipoprotein metabolism are discussed in this review as far as they are known. Furthermore, the tremendous elevations of Lp(a) in nephrotic syndrome and its primary and secondary causes are reviewed. Primary causes became recently apparent by a significantly higher frequency of low-molecular-weight apo(a) phenotypes in patients compared with controls. The secondary causes were shown by an increase of Lp(a) in all apo(a) isoform groups. Because Lp(a) is an LDL-like particle that is usually included in the measured or calculated LDL cholesterol fraction, the influence of the extremely high Lp(a) levels in NS on the measurement of LDL cholesterol is discussed. 相似文献
78.
79.
T Sch?fer B Przybilla A Galosi G Burow I Ljungstedt-Pahlman S Dreborg J Ring 《Annals of allergy》1992,68(4):334-339
The aim of this study was to compare the efficacy and safety of a monomethoxypolyethylene glycol (mPEG) modified grass pollen mix allergen preparation (mPEG-gm) and a partly purified grass pollen mix allergen preparation (gm) in hyposensitization (HS), evaluating both products at two dose levels. Thirty adult patients with allergic rhinoconjunctivitis were allocated into two treatment groups based on their sensitivity to conjunctival provocation tests (CPT). Treatment was given in a double-blind manner. The starting dose was 20 BU and was approximately doubled weekly up to 20,000 BU the first year and 120,000 BU the second year. Skin testing and CPT were performed before treatment and at each dose level. All patients reached 20,000 BU the first year. Twenty-five patients continued the second year. Twenty-one of those reached 120,000 BU (9/12 on mPEG-gm and 12/13 on gm). The frequency of general side effects was reduced by about 50% with the mPEG grass mix compared with native grass mix. A significant improvement in the conjunctival sensitivity was found in both treatment groups the second year (120,000 BU) but not the first year (20,000 BU). Seventy-eight percent of the patients in the gm group and 50% in the mPEG-gm group improved by CPT (not statistically significant). The skin sensitivity was reduced after 1 year at low dose in 69% of the gm-treated patients and 33% of the mPEG treated patients. After the second year at high dose levels, the skin sensitivity decreased in all patients.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
80.
Pharmacokinetics and acute toleration of the beta-carboline derivative abecarnil in man 总被引:1,自引:0,他引:1
Plasma levels of the beta-carboline, abecarnil (isopropyl 6-(benzyloxy)-4-(methoxymethyl)-9H-pyrido [3,4-b]indole-3- carboxylate, ZK112119) which is presently under development as an anxiolytic, were measured by HPLC with fluorescence detection in six healthy male volunteers given 30 micrograms/kg i.v. and 5 and 10 mg p.o. Following i.v. injection, plasma levels declined biphasically with half-lives of 6 min and 3.4 h. The total clearance was 13 ml/min/kg. After oral administration, maximum concentrations were reached after 2 h. The bioavailability was approximately 60%. The terminal half-life after p.o. administration was 7 h. No clinically relevant changes in ECG, vital signs or standard laboratory measurements occurred. Eight different adverse reactions were noted by the subjects. The most frequently reported side-effects were tiredness, dizziness, unsteady gait and lack of concentration. 相似文献