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71.
Zusammenfassung Im Gegensatz zur Volkeltschen, auf situationsbedingte Komplexqualitäten zurückgreifenden Deutung des Verhaltens der Spinne gegenüber der Beute innerhalb und außerhalb des Netzes wird gezeigt, daß die Spinne in weitestem Maße durch den isolierten Vibrationsreiz zur Fanghandlung bestimmt wird.Analog wird ein ebenso isolierbarer Einzelreiz aufgewiesen, der das Feindverhalten bewirkt, nämlich der durch die Luft übertragene Schwingungsreiz, der biologisch sinnvoll nur als Warnungssignal vor Wespen gedeutet werden kann.Ein direktes, nicht erst durch Netzschwingungen vermitteltes Wahrnehmen der Luftschwingungen wird trotz bisher nicht mit Sicherheit festgestellter Schallrezeptoren wahrscheinlich gemacht.Während in den Funktionskreisen des Feindes und der Beute dem situativen Moment gegenüber den scharfumrissenen Einzelreizen somit eine sehr geringe Bedeutung zukommt, gestaltet sich die Lage für die Volketsche Auffassung günstiger im Funktionsbereich des Netzbaues. Die Bedeutung bestimmter Merkmale hängt hier wesentlich ab von der Situation im Sinne der jeweils erreichten Phase der Bauhandlung.Allerdings genügt es nicht, unter der Situation nur die Gesamtheit der äußeren Gegebenheiten zu verstehen. Wesentlich ist auch die innere Situation, in der das Tier sich befindet und auf Grund deren objektiv gleiche Bedingungen eine Umstimmung erfahren. Dies wird durch zwei Experimente gezeigt, bei denen sowohl in der Phase des Radienspinnens als auch in der Phase des Fangfädenspinnens alle gesponnenen Fäden sofort wieder mit Hilfe glühender Nadeln zerstört werden. Trotz des hierdurch hervorgerufenen Fehlens der normalen äußeren Abschlußbedingungen für die einzelnen Phasen nimmt die Bauhandlung, wenngleich in verzögerter Weise, schließlich doch ihren normalen Verlauf.  相似文献   
72.
Objective: We examined predictors of weight loss with topiramate, an anticonvulsant associated with weight loss in adults. Research Methods and Procedures: In this uncontrolled, prospective clinical trial, topiramate was added to existing anticonvulsants in adults (40 to 110 kg) with partial‐onset seizures. Primary measurements were change from baseline weight after 3 months and 1 year in patients completing 1 year of topiramate treatment (N = 38). Physiological and metabolic measures were analyzed for correlation with weight loss during topiramate treatment. Results: In patients who completed 1 year of topiramate treatment, baseline weight was reduced in 82% at 3 months and in 86% at 1 year. Mean body weight was reduced 3.0 kg (3.9% of baseline) at 3 months and 5.9 kg (7.3%) at 1 year. In obese patients [body mass index (BMI) ≥ 30 kg/m2], mean weight loss was 4.2 kg (4.3%) at 3 months and 10.9 kg (11.0%) at 1 year. Weight loss was primarily caused by reduction in body fat mass. For all patients, weight loss at 3 months correlated most strongly with reduced caloric intake (p = 0.02). At 1 year, caloric intake had returned to baseline levels; weight loss correlated most strongly with higher baseline BMI (p = 0.0007). Discussion: Our results suggest that weight loss occurs in most adults treated with topiramate and is sustained for at least 1 year. Reduced caloric intake may account, in part, for weight loss during early treatment. The pattern of weight loss differs according to baseline BMI, with obese patients experiencing greater weight loss during continued therapy.  相似文献   
73.
Since 1991, Envirovet Summer Institutes have provided an intensive educational program in wildlife and ecosystem health to approximately 225 animal health professionals. Envirovet provides knowledge, skills, and multiple mentors to catalyze ecosystem health-oriented careers for young veterinarians. It is a total immersion experience, with the students engaged in 60–70 hours a week of instruction, 6–7 days a week, for 6 weeks. The course is comprised of lecture, laboratory, and field experiences organized into three sessions: 1) terrestrial wildlife and ecosystem health; 2) aquatic wildlife and ecosystem health; and 3) an ecosystem health approach to international development. Sessions 1 and 2 take place in Florida and Georgia; Session 3 takes place in a developing country (e.g., Kenya, Brazil, South Africa). Ultimately, the goal of Envirovet is to increase the numbers and effectiveness of veterinarians in productive ecosystem health research and application teams around the world.  相似文献   
74.
Natural curcumin was evaluated as a potential photosensitizer for oral applications. The photocytotoxicity of curcumin on salivary gland acinar cells (SM 10-12) was investigated in five aqueous preparations consisting of 5% DMSO, non-ionic micelles, cyclodextrin, liposomes, or a hydrophilic polymer. The difference in phototoxic effects between natural curcumin and synthetic curcumin was examined. Cytotoxicity in SM 10-12 cells exposed to curcumin in the concentration range 0.4-13.5 microM was investigated by MTT test, a fluorescence-staining microscopic test, and by Western immunoblotting techniques. The potential formation of a photoreaction product, hydrogen peroxide, was evaluated by a fluorescence assay. The light source was a halogen lamp used in the dental clinic, emitting mainly in the blue part of the spectrum. The phototoxic effect on SM 10-12 cells was dependent on curcumin concentration, the light dose and the type of preparation. Natural and synthetic curcumin induced phototoxicity to the same extent. Significant effects on the cells were obtained at low curcumin concentrations (< or =0.5 microM) and at a low light dose (< or =6 J cm(-2)), after 3 h incubation. Neither the activation of caspases-3, -7, -8 or -9, nor the formation of hydrogen peroxide could be detected in cells exposed to curcumin and light. The liposome preparation was the most efficient vehicle for curcumin to induce cell death. The phototoxic effect induced by curcumin is highly dependent on the type of preparation. Curcumin might be a potential photosensitizer in the treatment of oral lesions and cancers provided careful selection of the vehicle.  相似文献   
75.
Else Boken 《Plant and Soil》1970,33(1-3):645-652
Summary In pot experiments with a phosphorus-deficient soil and four barley varieties, Kenia, Maja, Bonus, and Pallas, receiving increasing amounts of phosphorus, it was found that the order of susceptibility to phosphorus deficiency of the varieties was the same for grain as for grain + straw, when the ranking was based on the percentage decrease in dry matter yield as a result of phosphorus deficiency based on the maximum obtained dry matter yield. Estimations of the maximum phosphorus utilization quotients of dry matter yield of grain + straw graduated the susceptibility to phosphorus deficiency of the varieties in the same order.  相似文献   
76.
Disaccharides are well-known reagents to protect biostructures like proteins and phospholipid-based liposomes during freezing and drying. We have investigated the ability of the two disaccharides trehalose and sucrose to stabilize a novel, non-phospholipid-based liposomal adjuvant composed of the cationic dimethyldioctadecylammonium (DDA) and trehalose 6,6'-dibehenate (TDB) upon freeze-drying. The liposomes were freeze-dried using a human dose concentration containing 2.5 mg/ml DDA and 0.5 mg/ml TDB with varying concentrations of the two sugars. The influence on particle size upon rehydration was investigated using photon correlation spectroscopy (PCS) and the gel to fluid phase transition was examined by differential scanning calorimetry (DSC). Data revealed that concentrations above 211 mM trehalose protected and preserved DDA/TDB during freeze-drying, and the liposomes were readily rehydrated. Sucrose was less efficient as a stabilizer and had to be used in concentrations above 396 mM in order to obtain the same effect. Immunization of mice with the tuberculosis vaccine candidate Ag85B-ESAT-6 in combination with the trehalose stabilized adjuvant showed that freeze-dried DDA/TDB liposomes retained their ability to stimulate both a strong cell-mediated immune response and an antibody response. These findings show that trehalose at isotonic concentrations protects cationic DDA/TDB-liposomes during freeze-drying. Since this is not the case for liposomes based on DDA solely, we suggest that the protection is facilitated via direct interaction with the headgroup of TDB and a kosmotropic effect, whereas direct interaction with DDA plays a minor role.  相似文献   
77.
78.
Balancing forest conservation with resource extraction by local people is challenging. In the mountain forests of Bwindi Impenetrable National Park in Uganda, this was addressed by permitting regulated access to certain forest products in specific areas by authorized local people. However, it remained unclear whether harvest levels were biologically sustainable. Here, we used matrix population models and long‐term data to examine the impacts of bark harvesting on population dynamics of two important medicinal plants, Rytigynia kigeziensis and Ocotea usambarensis, in Bwindi. Only 4% of R. kigeziensis and 3% of O. usambarensis stems (>1.3 m height) showed signs of bark harvest, mostly mild harvesting. We found that the harvested populations of both species appeared stable or will moderately grow in the long run. Modelled population growth rates were mostly determined by survival probabilities. Similarity between the stable stage distributions predicted by the model and observed population structures suggests that our estimated vital rates (growth, recruitment and survival rates) are a reasonable representation of actual values in these populations. Thus, recent harvest levels of R. kigeziensis and O. usambarensis appear sustainable. Nonetheless, monitoring of harvested and unharvested populations by tagging, marking and remeasuring individuals should continue for both species.  相似文献   
79.
In Western Europe, many pond owners introduce amphibians for ornamental purposes. Although indigenous amphibians are legally protected in most European countries, retailers are circumventing national and international legislation by selling exotic nonprotected sibling species. We investigated to what extent non‐native species of the European water frog complex (genus Pelophylax) have become established in Belgium, using morphological, mitochondrial and nuclear genetic markers. A survey of 87 sampling sites showed the presence of non‐native water frogs at 47 locations, mostly Marsh frogs (Pelophylax ridibundus). Surprisingly, at least 19% of all these locations also harboured individuals with mitochondrial haplotypes characteristic of Anatolian water frogs (Pelophylax cf. bedriagae). Nuclear genotyping indicated widespread hybridization and introgression between P. ridibundus and P. cf. bedriagae. In addition, water frogs of Turkish origin obtained through a licensed retailer, also contained P. ridibundus and P. cf. bedriagae, with identical haplotypes to the wild Belgian populations. Although P. ridibundus might have invaded Belgium by natural range expansion from neighbouring countries, our results suggest that its invasion was at least partly enhanced by commercial trade, with origins as far as the Middle East. Also the invasion and rapid spread of Anatolian lineages, masked by their high morphological similarity to P. ridibundus, is likely the result of unregulated commercial trade. We expect that Anatolian frogs will further invade the exotic as well as the native range of P. ridibundus and other Pelophylax species elsewhere in Western and Central Europe, with risks of large‐scale hybridization and introgression.  相似文献   
80.
Immunotherapy targeting the hTERT subunit of telomerase has been shown to induce robust immune responses in cancer patients after vaccination with single hTERT peptides. Vaccination with dendritic cells (DCs) transfected with hTERT mRNA has the potential to induce strong immune responses to multiple hTERT epitopes and is therefore an attractive approach to more potent immunotherapy. Blood samples from such patients provide an opportunity for identification of new, in vivo processed T-cell epitopes that may be clinically relevant. A 62-year-old female patient underwent radical surgery for a pancreatic adenocarcinoma. After relapse, she obtained stable disease on gemcitabine treatment. Due to severe neutropenia, the chemotherapy was terminated. The patient has subsequently been treated with autologous DCs loaded with hTERT mRNA for 3 years. Immunomonitoring was performed at regular intervals following start of vaccination and clinical outcome measured by CT and PET/CT evaluation. The patient developed an immune response against several hTERT-derived Th and CTL epitopes. She presently shows no evidence of active disease based on PET/CT scans. No serious adverse events were experienced and the patient continues to receive regular booster injections. We here provide evidence for the induction of hTERT-specific immune responses following vaccination of a pancreas cancer patient with DCs loaded with hTERT mRNA. These responses are associated with complete remission. A thorough analysis of this patient immune response has provided a unique opportunity to identify novel epitopes, associated with clinical effects. These will be included in future hTERT vaccines.  相似文献   
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