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81.
P. Rokkanen O. Böstman E. Hirvensalo E. A. Mäkelä E. Partio H. Pätiälä S. Vainionpää K. Vihtonen P. Törmälä 《European journal of orthopaedic surgery & traumatology : orthopedie traumatologie》1992,2(2):107-110
Résumé L'utilisation de matériaux d'ostéosynthèse biodégradables a l'avantage d'éviter la réintervention pour extraire le matériel. Les biomatériaux de polymères polyglycolides ont été expérimentés sur plus de 3 600 animaux de laboratoire avant leur introduction en pratique clinique. Depuis 1984 nous les avons utilisés comme matériau d'ostéosynthèse dans près de 1 700 cas parmi lesquels 880 cas de fracture malléolaire, 226 cas d'ostéotomie en chevron pour hallux valgus, 65 cas de fracture de la tête radiale et 54 cas de fracture de l'olécrane. Parmi les 800 premiers cas traités par broches biodégradables nous avons obtenu des résultats favorables et sans incidents dans 91 pour cent des cas. Il y eut 7 cas de fixation défaillante nécessitant une réintervention. Il y a eu 7 cas d'infection superficielle et 3 cas d'infection profonde. Nous avons observé la formation d'une collection séreuse sous-cutanée sans influence sur le résultat radiologique ou clinique dans 52 cas (6,5 %). Au vue de ces résultats et compte tenu des avantages économiques et psychologiques des matériaux biodégradables (pas de réintervention), on peut penser que l'usage de biomatériaux rivalise favorablement avec l'usage de matériaux conventionnels dans certains types d'ostéosynthèse.
Utilization of biodegradable implants in the surgical treatment of fractures and osteotomies
Summary The utilization of biodegradable implants instead of metals in orthopaedic surgery abolishes the need to remove the fixation material. For this study biodegradable rods and screws of self-reinforced polyglycolide, polylactide and lactide-glycolide copolymer were developed and manufactured. The clinical introduction of these implants was preceded by thorough experimental studies with 3 600 animals. From November 1984 the developed biodegradable method of osteofixation was used in 1 700 operations. These included 880 displaced malleolar fractures, 226 chevron-osteotomy for hallux valgus, 65 displaced fracture of the radial head, 54 displaced frature of the olecranon and other fresh fractures or orthopaedic operations. In the first 800 cases operated on using self-reinforced polyglycolide rods the postoperative course was uneventful (91%). Because of failure in the fixation reoperation was needed in 7 cases. A superficial wound infection was observed in 7 cases, deep infection in 3 and transient fluid accumulation in 52 cases (6,5%). Fluid accumulation did not influence the radiological or clinical end-result. The advantages of biodegradable fixation are many-sided. There is a costbenefit and clinical capacity is free for other use, and psychological advantages must be emphasised because removal of implants is not needed. The over all results of this study were considered favourable.相似文献
82.
F. Röpke K. Klingebiel H. J. Hein R. Taute 《Archives of gynecology and obstetrics》1993,254(1-4):1159-1160
Schlu?folgerungen Aus der Me?wert-Verteilung der Grauwerte im Sonogramm lassen sich Kennwerte berechnen, die eine computergestützte sonographische
Reifebeurteilung der Plazenta erm?glichen. Allerdings sind die Verteilungsparameter (Median, Varianz, Schiefe, Exze?) abh?ngig
von den Ger?teparametern. Zuverl?ssiger ist die Berechnung von Kennwerten, die sich auf die strukturellen Eigenschaften des
Sonogramms beziehen. Bei den hier dargestellten Untersuchungen k?nnen Kennwerte für den Kontrast bzw. für die Ansammlung gleichartiger
Grauwerte um einen bestimmten Punkt die sonographische Beurteilung der Plazenta optimieren. Damit erweitern sich die M?glichkeiten
für die Zustandsdiagnostik der intrauterinen Lebensbedingungen. 相似文献
83.
84.
Bojan Pajic Grigoris Pallas Gerding Heinrich Matthias Böhnke 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2006,244(1):22-27
Purpose It was the aim of this study to investigate the efficacy, longevity, and safety of a new ab interno intervention for the treatment
of primary open-angle glaucoma (POAG).
Methods The previously described method of radiofrequency-mediated “sclerothalamotomy ab interno” was applied in 53 eyes of consecutive
patients with POAG between April 2002 and July 2002. Average preoperative intraocular pressure (IOP) was 25.6±2.3 mmHg (range
18–48 mmHg). Sclerothalamotomies were carried out with a custom-made high-frequency dissection 19 G probe (tip 0.3×1 mm) applying
bipolar current with a frequency of 500 kHz (tip temperature 130°C).
Results After a follow-up period of 24 months, the average IOP was 15.0±1.6 mmHg (range 11–20 mmHg) (p<0.005). The average number of topical agents was 2.6±1.0 (range 1–5) preoperatively. Twenty-four months after surgery such
agents were used in only five (9.6%) eyes and the average was 0.21±0.53 (range 0–2). Transient IOP elevation was observed
in 12 of 53 eyes (22.6%) postoperatively. In all cases elevated IOP could efficiently be controlled with topical medication.
In general, IOP dropped continuously over the course of the 6 months following surgery and then remained constant.
Conclusions This study indicates that sclerothalamotomy ab interno is a safe and efficient surgical method for the treatment of POAG.
Long-term results clearly demonstrate the longevity of IOP reduction. 相似文献
85.
86.
Prof. Dr. E. Minar B. Pokrajac R. Wolfram A. Budinsky C. Kirisits R. Pötter 《Gef?sschirurgie》2003,8(2):75-84
The therapeutic concept of irradiation of the vessel wall for prevention of restenosis after endovascular procedures is based on increasing knowledge about the pathophysiology of the process leading to restenosis. There is until now only a limited number of studies concerning the use of brachytherapy (BT) in the peripheral circulation, which is in contrast to the already large experience in the coronary circulation. In the peripheral trials the radiation dose was administered by a remote afterloader using a gamma source. According to the available data, vascular BT is a promising technology with the potential to reduce the restenosis rate. The Vienna-2-Trial was the first randomised study to demonstrate the efficacy of endovascular BT for prophylaxis of restenosis after femoropopliteal percutaneous transluminal angioplasty. However, we have to await further supportive data from ongoing clinical trials before definitive recommendations can be given. Currently, endovascular BT seems already justified in patients with recurrent interventions or after long-segment femoropopliteal angioplasty because of the high risk of restenosis in these patients. The next years will demonstrate the ultimate role of endovascular BT in comparison to the rapidly evolving field of drug-eluting stents. 相似文献
87.
88.
K. H. Vogelberg M. Mühl M. Köhler 《Journal of molecular medicine (Berlin, Germany)》1987,65(15):713-718
Summary Seventy-five diabetic and 40 nondiabetic subjects who where suffering from peripheral vascular disease were studied in order to determine whether the degree of the severity of their disease can be better calculated by Doppler ultrasound examinations of the peak velocity than by the systolic pressure of the peripheral bloodstream. In 46 examinations of normal controls the mean value of the peak velocity was 13.3±3.3 cm/s with a standard deviation of 15.4%±13.2% on one day and 16.1%±15.9% on different days. Considering patients with or without diabetes mellitus the velocity was significantly decreased in correlation to an increasing degree of severity of the vascular disease (P<0.001); however, the decrease was lower in diabetic than in nondiabetic subjects (6.9±2.8 vs 4.6±6.2,P<0.05). The systolic pressure hardly decreased, but remained higher in all stages of peripheral vascular disease of diabetics than in the nondiabetic subject (P<0.05 toP<0.005). There was a significant decrease of the systolic pressure only in diabetic subjects with the most advanced degree of the disease, i.e. stage IV (P<0.05).It is concluded from this study that Doppler ultrasound measurements of the peak velocity of the peripheral bloodstream are a useful parameter to calculate the degree of severity of the peripheral vascular disease. In addition, it is concluded than peak velocity is an even better prognostic indicator of peripheral vascular disease than is measurement of the systolic blood pressure at the feet.
Abkürzungen AVK periphere arterielle Verschlußkrankheit - USDI Ultraschall-Doppler-Index - MSBG maximale Blutströmungsgeschwindigkeit - HFV Herzfrequenzvariation 相似文献
Abkürzungen AVK periphere arterielle Verschlußkrankheit - USDI Ultraschall-Doppler-Index - MSBG maximale Blutströmungsgeschwindigkeit - HFV Herzfrequenzvariation 相似文献
89.
Dr. J.-T. Gräsner M. Fischer K. H. Altemeyer J. Bahr B. W. Böttiger V. Dörges R. Franz A. Gries H. Krieter M. Messelken T. Rosolski M. Ruppert T. Schlechtriemen J. Scholz J. Schüttler B. Wolke J. F. Zander 《Notfall & Rettungsmedizin》2005,8(2):112-115
Within the scope of the symposium “Rescue Medicine in Germany” (held at the Reisensburg near Ulm in 2002), the need for a standardized data acquisition set for prehospital cardiac arrest patients was identified. Therefore, the working group “Emergency Medicine” of the German Society of Anesthesiology and Intensive Care Medicine (DGAI) created a nationwide data acquisition system for primary medical care in prehospital cardiac arrest patients treated with cardiopulmonary resuscitation procedures. The system is in full accordance with the “Utstein style.” Integration of this data acquisition system, for example into the “Dortmund protocol,” is providing a standardized data web base of all acquired prehospital data analyze and to compare processing and structural quality. As additional modules for this nationwide data web base system, an inhospital module “further clinical treatment” and a “long-term follow-up” module are currently in the developmental process. 相似文献
90.
U. Böhling H. Schamberger U. Grittner J. Scholz 《Journal of orthopaedics and traumatology》2005,6(2):69-75
Abstract The objective of the study was to evaluate the precision, concordance, practicability and the early clinical outcome of the use of a computerised navigation system in a comparative study with a group of 100 patients. Two groups of 50 patients each underwent implantation of a bicondylar knee prosthesis either by means of the freehand navigation system or by means of technical instrumentation. We found that the computerised navigation system provided a higher precision than the technically instrumented implantation: 94% of the prostheses implanted with the navigation system have an alignment within a range of -3° to 3° on of the Mikulicz line. Only 46% of the patients operated by means of the technical instrumentation reached this aspired result. Furthermore, the navigation system showed smaller ranges in the deviation of the aspired alignment. The radiological and computer-modeled alignment values differed both pre- and postoperatively, but to a larger extent before surgery. The varus or valgus deviations of the axis were more distinct radiologically under the weight of the patient’s body than in the computer model. The clinical outcome examined by the use of the HSS score after a mean followup of 7 months is good in both groups, and without significant differences. On average, the duration of surgery was 13 minutes longer in the computerised navigation group. We conclude that the benefit of the computerised navigation system is represented by the high improvement of precision. Achieving early clinical results identical to those in the technical instrumentation group, we expect a reduction of aseptic loosening in the computerised navigation group. 相似文献