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21.
Kopp MV Brauburger J Riedinger F Beischer D Ihorst G Kamin W Zielen S Bez Friedrichs F Von Berg A Gerhold K Hamelmann E Hultsch Kuehr J 《The Journal of allergy and clinical immunology》2002,110(5):728-735
BACKGROUND: Binding of allergens with IgE to the IgE receptors on mast cells and basophils results in the release of inflammatory mediators as sulfidoleukotrienes (SLTs), triggering allergic cascades that result in allergic symptoms, such as asthma and rhinitis. OBJECTIVE: We sought to investigate whether anti-IgE (Oma-lizumab), a humanized monoclonal anti-IgE antibody, in addition to specific immunotherapy (SIT) affects the leukotriene pathway. METHODS: Ninety-two children (age range, 6-17 years) with sensitization to birch and grass pollens and with seasonal allergic rhinitis were included in a phase III, placebo- controlled, multicenter clinical study. All subjects were randomized to one of 4 treatment groups. Two groups subcutaneously received birch SIT and 2 groups received grass SIT for at least 14 weeks before the start of the birch pollen season. After 12 weeks of SIT titration, placebo or anti-IgE was added for 24 weeks. The primary clinical efficacy variable was symptom load (ie, the sum of daily symptom severity score and rescue medication score during pollen season). Blood samples taken at baseline and at the end of study treatment after the grass pollen season were used for separation of leukocytes in this substudy. After in vitro stimulation of the blood cells with grass and birch pollen allergens, SLT release (LTC4, LTD4, and LTE4) was quantified by using the ELISA technique. RESULTS: Before the study treatment, SLT release to birch and grass pollen exposure did not differ significantly among the 4 groups. Under treatment with anti-IgE + SIT-grass (n = 23), a lower symptom load occurred during the pollen season compared to placebo + SIT-grass (n = 24, P =.012). The same applied to both groups receiving birch SIT (n = 23 and n = 22, respectively; P =.03). At the end of treatment, the combination of anti-IgE plus grass SIT, as well as anti-IgE plus birch SIT, resulted in significantly lower SLT release after stimulation with the corresponding allergen (416 ng/L [5th-95th percentile, 1-1168] and 207 ng/L [1-860 ng/L], respectively) compared with placebo plus SIT (2490 ng/L [384-6587 ng/L], P =.001; 2489 ng/L [1-5670 ng/L], P =.001). In addition, treatment with anti-IgE was also followed by significantly lower SLT releases to the allergens unrelated to SIT (grass SIT: 300 ng/L [1-2432 ng/L] in response to birch allergen; birch SIT: 1478 ng/L [1-4593 ng/L] in response to grass pollen) in comparison with placebo (grass SIT: 1850 ng/L [1-5499 ng/L], P =.001; birch SIT: 2792 ng/L [154-5839 ng/L], P =.04]. CONCLUSION: Anti-IgE therapy reduces leukotriene release of peripheral leukocytes stimulated with allergen in children with allergic rhinitis undergoing allergen immunotherapy independent of the type of SIT allergen used. 相似文献
22.
I. Simonitsch C. W. Kopp I. Mosberger T. Radaszkiewicz B. Volc-Platzer 《Virchows Archiv : an international journal of pathology》1996,427(5):477-481
The cutaneous lymphocyte associated antigen (CLA) recognized by the monoclonal antibody (moAb) HECA-452 plays a major role in the homing of lymphocyte subpopulations to the skin by binding to E-selectin on dermal microvessels. The factors responsible for the immigration of Langerhans cells (LC) and their precursors into the skin are still unknown, but because normal resting LC are also capable of expressing CLA, the antigen was proposed as a candidate LC-homing structure. To gain insight into these mechanisms, the expression of HECA-452 on neoplastic LC within and outside the skin was investigated in paraffin-embedded sections from 44 patients with localized and disseminated forms of Langerhans cell histiocytosis (LCH) presenting with proliferating cells positive for CD45, CD1a, S100 and HLADR. Irrespective of the clinical presentation or the type of organ involved, HECA-452-positive LC were detected in all biopsies tested (range 5->90%). The most prominent HECA-452 reactivity was observed in skin lesions and in areas with accumulations of eosinophilic granulocytes. Our data provide evidence for a heterogeneous expression of sLex/sLea structures in various stages of activated and/or differentiated LCH cells. Remarkably, CLA-antigen expression on LCH-cells was not restricted to cutaneous sites. In view of recent findings on the expression of HECA-452 on resting epidermal LC, our data are compatible with the view that local cytokine production by keratinocytes or cells from the surrounding infiltrate induce and/or modulate CLA expression on LC in both cutaneous and extra-cutaneous sites.This work is dedicated to Professor Dr. Thaddäus Radaszkiewicz, who died in September 1995 相似文献
23.
Kopp R Bernsberg R Kashefi A Mottaghy K Rossaint R Kuhlen R 《The International journal of artificial organs》2005,28(12):1272-1277
Hirudin serves as an alternative anticoagulant for extracorporeal blood circulation. Comparing anticoagulation with hirudin (2.5 or 5.0 microg/mL) and heparin (2.0 or 4.0 IU/mL) human blood was circulated in a modified 'Chandler System' using PVC-tubes for 2 hours at 37 degrees C. Activation of coagulation (thrombin-antithrombin III-complex, prothrombin fragment 1+2 and D-Dimer), platelet (platelet factor 4 - PF4) and complement systems was analyzed. Both heparin concentrations and 5.0 microg/dL hirudin led to as significantly less activated plasmatic coagulation as 2.5 microg/dL hirudin. Decreased levels of PF4 and anaphylatoxin C5a (p<0.05) as well as terminal complement complex demonstrated improved hemocompatibility after anticoagulation with heparin in contrast to hirudin. Because initial coagulation cascade, platelet activation and complement activation is less influenced by hirudin than by heparin, hemocompatibility is more dependent on the characteristics of the biomaterials used. This predestines hirudin as anticoagulant for in vitro studies analyzing hemocompatibility of biomaterials or surface modifications. 相似文献
24.
In leaves of CONVALLARIA MAJALIS L. the cardenolide content is known to decrease towards the end of the vegetation period. However, at this stage the rate of biosynthesis is even higher than at the onset of flowering. This has been revealed by photosynthesis experiments in the presence of (14)CO (2) and the subsequent isolation of 15 labelled cardenolides using PC, TLC and HPLC. IN VITRO and IN VIVO experiments showed that the first step in the degradative pathway of convalloside is deglucosidation yielding convallatoxin, followed by conversion into several yet unidentified degradation products other than known cardenolides of C. MAJALIS. This indicates that the cardenolides of C. MAJALIS are subjected to a turnover at least towards the end of the vegetation period. 相似文献
25.
Investigation of post mortem neurobiochemical changes is an important field in biological psychiatry which allows analyses of the analogies between peripherical markers and the central neurochemical processes they represent. Our study discusses the pathological neuroanatomy (collection and conservation of the anatomical specimens) and clinical criteria (selection of an evaluation and diagnostic scale, analysis of results of retrospective clinical interviews: "the psychological autopsy"). We also discuss the many methodological issues which arise in interpretations of these correlations. We wish to encourage others to apply a standardized methodology to these scientific studies of post mortem neurochemical parameters and retrospective clinical diagnosis. 相似文献
26.
27.
From bulbs of URGINEA PANCRATION (Steinh.) G. de Philippe (Hyacinthaceae) 5 bufadienolides were isolated by a combination of column and droplet counter-current chromatography; their structures were elucidated mainly by FAB-MS and (1)H- and (13)C-NMR spectroscopy. Besides the already known scilliglaucoside ( 1), scillirubroside ( 2), and scilliroside ( 3), two new bufadienolides were identified: 5alpha-4,5-dihydroscillirosidin- 3beta- O-alpha- L-thevetosido-4'-beta- D-glucopyranoside and arenobufagin-3beta- O- L-rhamnopyranosido-4'-beta- D-glucopyranoside. 相似文献
28.
Tanja Neupert Gabriele Ihorst Wilfried Karmaus Thomas Frischer Matthias Kopp Christel Ulmer Brigitte Schwöbel Johannes Forster Joachim Kühr 《Zeitschrift fur Gesundheitswissenschaften》1997,5(1):63-75
Conclusion
Geographical differences in morbidity of asthma and asthmalike complaints were ascertained and remained stable after adjustment for potential confounders. However, the choice of the way of presentation (relative risk versus deviation from the weighted mean of the prevalences) can provoke different suggestive effects. 相似文献29.
From 1973 to 1991 a total of 422 patients underwent surgery because of an abdominal trauma. 12 patients had gunshot wounds and 46 patients stab wounds. In a retrospective study the diagnostic and therapeutic procedure and the indication for surgery are analysed. After gunshot wounds of the abdomen we always performed a laparotomy. In 11 od 12 cases we found serious intra-abdominal injuries. Only in one case the laparotomy was "unnecessary", because of a tangential wound without penetrating of the abdominal wall. After stab wounds the diagnostic and therapeutic management was more selective. Indications for mandatory laparotomy after stab wounds were a manifest hemorrhagic shock, evisceration and a still left weapon in the abdomen (n = 22). The first clinical examination was completed by ultrasound or peritoneal lavage. Pathological findings like free intraperitoneal fluid or a positive lavage also were indications for laparotomy (n = 9). The other patients were observed closely, including repeated physical examination. The indication for surgery then based on the development of clinical signs. The time between first examination and laparotomy was never more than 12 hours. 39 patients (84.7%) had injuries of intraabdominal organs. 5 patients (10.8%) had a negative laparotomy. The mortality rate was 3.4%, but there was no death as a result of the selective approach. 相似文献
30.
H Wang A Sarrieau D Pélaprat B P Roques A Vanhove N Kopp Z Q Chi W Rostène 《Synapse (New York, N.Y.)》1991,8(3):177-184
Binding properties and localization of [3H]ohmefentanyl, a new ligand for mu opioid receptors, were investigated on normal human brain sections. Binding assays performed at the level of the basal ganglia revealed: (1) a steady-state binding reached after 60 min incubation at room temperature, (2) the presence, in saturation experiments, of an apparent single class of binding sites with a Kd = 1.68 +/- 0.45 nM and a Bmax = 162 +/- 9 fmol/mg protein, (3) an order of potency to inhibit [3H]ohmefentanyl binding as follows: ohmefentanyl greater than [D-Ala2, MePhe4, Gly-ol5] enkephalin (DAGO) greater than ethylketocyclazocine (EKC) much greater than Tyr-D-Ser(OtBu)-Gly-Phe-Leu-Thr(OtBu) (BUBU) and U-50,488H. Quantitative autoradiography showed an heterogeneous distribution of [3H]ohmefentanyl binding sites with the highest densities in amygdala, medical geniculate body, thalamus, and caudate nucleus. Binding characteristics and anatomical distribution also show that [3H]ohmefentanyl may bind to a small proportion of additional sites called "DAGO-inaccessible [3H]ohmefentanyl specific binding sites." [3H]Ohmefentanyl binding to these sites can be partly inhibited by sigma ligands such as 1,3-di-o-tolylguanidine (DTG) and haloperidol. However, unlabeled DAGO inhibited more than 80% of [3H]ohmefentanyl specific binding in most of the human brain regions studied, suggesting that the major population of sites labeled by [3H]ohmefentanyl represented mu opioid receptors. 相似文献