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991.
Respiration rate, heart rate, and body temperature values were obtained from 14 cynomolgus monkeys (Macaca fascicularis) during neurosurgery under barbiturate anesthesia. Vital sign values markedly declined below baseline during the early stages of surgery, steadily increased as surgery progressed and neared completion, and finally returned to baseline by the end of the postsurgical recovery period. There was considerable variability among the 14 monkeys, but the ranking of each monkey relative to the others remained constant across the period of observation. The findings suggested that the cynomolgus monkey may be more sensitive to barbiturates than the rhesus monkey, and cynomolgus monkeys may exhibit considerable individual differences in their sensitivity to barbiturates.  相似文献   
992.
《Endocrine practice》2021,27(8):783-789
ObjectiveWe conducted a posthoc analysis of the VIVID study (Safety and Efficacy of Human Regular U-500 Insulin Administered by Continuous Subcutaneous Insulin Infusion Versus Multiple Daily Injections in Subjects With Type 2 Diabetes Mellitus: A Randomized, Open-Label, Parallel Clinical Trial), comparing 2 delivery methods of human regular U-500 insulin (U-500R), continuous subcutaneous insulin infusion (CSII) versus multiple daily injection (MDI), in type 2 diabetes requiring high insulin, to determine influence of prestudy insulin on glycemic outcomes.MethodsWe compared A1C, total daily insulin dose (TDD), weight, and hypoglycemia by subgroups of prestudy insulin (prestudy U-500R vs non-U-500R) and treatment (CSII vs MDI).ResultsAt baseline, prestudy U-500R had higher TDD, higher body mass index, lower A1C and fasting plasma glucose, and higher rate of hypoglycemia compared to non-U-500R. Active titration of U-500R reduced A1C in both subgroups, with maximum benefit at 8 weeks. At 26 weeks, CSII provided the greatest reduction in A1C in both subgroups, with a greater reduction in non-U-500R. MDI provided an A1C reduction in both subgroups, with the greater reduction in non-U-500R. At 8 weeks, prestudy U-500R reached its lowest A1C; thereafter, A1C rebounded with MDI and remained stable with CSII. In non-U-500R, A1C continued to decrease to study end. In non-U-500R, hypoglycemia increased during active titration, but then decreased in the posttitration maintenance period. In both subgroups, TDD increased from baseline with MDI but not with CSII. Body weight increased in both subgroups but was greater in prestudy U-500R with CSII compared to MDI.ConclusionRegardless of previous insulin, people on high-dose insulin could lower A1C with U-500R, with additional benefit from CSII. These results may provide guidance for use of U-500R in clinical practice.  相似文献   
993.
Oxygen and glucose biosensors have been designed, fabricated, characterized and optimized for real-time continuous monitoring on a new smart catheter for use in patients with traumatic brain injury (TBI). Oxygen sensors with three-electrode configuration were designed to achieve zero net oxygen consumption. Glucose sensors were based on the use of platinum nanoparticle-enhanced electrodes that were modified with polycation and glucose oxidase immobilized by chitosan matrix. An iridium oxide electrode was developed to work as a biocompatible reference electrode with enhanced durability and stability in the biological solutions. A study of the effect of temperature on oxygen sensor performance, and both temperature and oxygen effects on glucose sensor performance were accomplished to enhance their operative stability and provide useful information for in vivo applications. A new methodology for automatic correction of the temperature and oxygen dependence of biosensor outputs is demonstrated through programmed LabView™ software. In vitro experiments in both physiological and pathophysiological ranges (oxygen: 0–60 mmHg; glucose: 0.1–10 mM; temperature: 25–40 °C) with clinical samples of cerebrospinal fluid obtained from TBI patients have demonstrated stable measurements with enhanced accuracy, indicating the feasibility of the sensors for a real-time continuous in vivo monitoring.  相似文献   
994.
995.
分别使用恒化装置和全玻璃发酵罐连续培养多变鱼腥藻。在稳定条件下加以周期性的光照(L∶D=12∶12),经5—6d得到半稳定状态连续培养物。在光照阶段,培养物的生物量增长速度约等于稀释速度D的两倍,叶绿素的增长速度略小于D的两倍,糖原的累积速度几乎高出D~5的一个数量级。细胞内糖原和蛋白质含量变化的时间过程反映出培养物在光-暗条件下的碳氮物质合成与消耗相互联系的代谢特点。半稳定状态连续培养受培养物内在的生理活性支配,生长参数的变化符合方程X=X_(oe)~((μ-D)~t),但不同于恒浊培养和恒化培养。外界因素的强弱变化只改变生长参量变化的强度。本法适用于研究微藻的生态生理。  相似文献   
996.
Dynamic models of many processes in the biological and physical sciences give systems of ordinary differential equations called compartmental systems. Often, these systems include time lags; in this context, continuous probability density functions (pdfs) of lags are far more important than discrete lags. There is a relatively complete theory of compartmental systems without lags, both linear and non-linear [SIAM Rev. 35 (1993) 43]. The authors extend their previous work on compartmental systems without lags to show that, for discrete lags and for a very large class of pdfs of continuous lags, compartmental systems with lags are equivalent to larger compartmental systems without lags. Consequently, the properties of compartmental systems with lags are the same as those of compartmental systems without lags. For a very large class of compartmental systems with time lags, one can show that the time lags themselves can be generated by compartmental systems without lags. Thus, such systems can be partitioned into a main system, which is the original system without the lags, plus compartmental subsystems without lags that generate the lags. The latter may be linear or non-linear and may be inserted into main systems that are linear or non-linear. The state variables of the compartmental lag subsystems are hidden variables in the formulation with explicit lags.  相似文献   
997.
We propose a (time) multiscale method for the coarse-grained analysis of collective motion and decision-making in self-propelled particle models of swarms comprising a mixture of ‘naïve’ and ‘informed’ individuals. The method is based on projecting the particle configuration onto a single ‘meta-particle’ that consists of the elongation of the flock together with the mean group velocity and position. We find that the collective states can be associated with the transient and asymptotic transport properties of the random walk followed by the meta-particle, which we assume follows a continuous time random walk (CTRW). These properties can be accurately predicted at the macroscopic level by an advection-diffusion equation with memory (ADEM) whose parameters are obtained from a mean group velocity time series obtained from a single simulation run of the individual-based model.  相似文献   
998.
PurposeEvaluation of a deep learning approach for the detection of meniscal tears and their characterization (presence/absence of migrated meniscal fragment).MethodsA large annotated adult knee MRI database was built combining medical expertise of radiologists and data scientists’ tools. Coronal and sagittal proton density fat suppressed-weighted images of 11,353 knee MRI examinations (10,401 individual patients) paired with their standardized structured reports were retrospectively collected. After database curation, deep learning models were trained and validated on a subset of 8058 examinations. Algorithm performance was evaluated on a test set of 299 examinations reviewed by 5 musculoskeletal specialists and compared to general radiologists’ reports. External validation was performed using the publicly available MRNet database. Receiver Operating Characteristic (ROC) curves results and Area Under the Curve (AUC) values were obtained on internal and external databases.ResultsA combined architecture of meniscal localization and lesion classification 3D convolutional neural networks reached AUC values of 0.93 (95% CI 0.82, 0.95) for medial and 0.84 (95% CI 0.78, 0.89) for lateral meniscal tear detection, and 0.91 (95% CI 0.87, 0.94) for medial and 0.95 (95% CI 0.92, 0.97) for lateral meniscal tear migration detection. External validation of the combined medial and lateral meniscal tear detection models resulted in an AUC of 0.83 (95% CI 0.75, 0.90) without further training and 0.89 (95% CI 0.82, 0.95) with fine tuning.ConclusionOur deep learning algorithm demonstrated high performance in knee menisci lesion detection and characterization, validated on an external database.  相似文献   
999.
This study compared the effects of drug combinations commonly used for chemical restraint of southern elephant seals. The combinations were: ketamine and diazepam, ketamine and midazolam, ketamine and xylazine, and tiletamine and zolazepam. The main aims were to gather basic information regarding the response of the animals to the different combinations, and to determine which were most useful for routine chemical restraint. All drug combinations could be used safely although apnea and whole-body shaking occurred with each. There were significant differences in several of the responses measured. Poor muscle relaxation and prolonged apnea were associated with ketamine and diazepam use. Animals given ketamine and xylatine were more depressed, took longer to recover, had a higher incidence of thermoregulatory problems, and lower heart rate than after other combinations. Ketamine and midazolam and tiletamine and zolazepam produced fewer complications than the other drug combinations, and tiletamine and zolazepam showed greater predictability of response and ease of use, making it preferable for use by people with little experience in anesthesia of elephant seals.  相似文献   
1000.
Carbon dioxide (CO2) exposure is a common method of anesthesia in studies of Drosophila melanogaster. A number of negative side effects of CO2 anesthesia have been reported. It is not clear whether the length of CO2 anesthesia time affects Drosophila survival in aging research. Here, we examined the potential effect of the CO2 anesthesia time length of 10–150 min. We found that long CO2 exposure could lead to Drosophila death, more significant in males. The longer the anesthesia time is, the longer it takes for flies to wake up. Long-time CO2 anesthesia can reduce the lifespan. Our stress tests showed that long-time CO2 anesthesia can increase the average survival time in both males and females under starvation conditions, but can only increase female lifespan under H2O2 oxidative stress. Long-time CO2 anesthesia also significantly affects physiological traits, with spontaneous activity increased in females but decreased in males, and reduced female fecundity. Our study suggests that limiting the CO2 anesthesia time and giving enough recovery time before performing physiological tests are important in Drosophila aging research.  相似文献   
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