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81.
Stability analysis of four-point walking   总被引:1,自引:0,他引:1  
The aim of the experiment reported here was to determine the static and dynamic stability of two-point stance phases when walking on hands and knees at different speeds. In addition, we defined the methods and predicted the consequences of including two-point stance phases into crutch assisted functional electrical stimulation (FES) walking. Crawling on hands and knees was performed at three speeds by five healthy male persons. With twelve joint-position markers placed on the subject, we determined two stability indices for every instant of gait. We analysed the peak values of these two indices during the two-point stance phases. The results indicate that we have to ensure the proper position of the centre of gravity to increase the speed of walking. To reach speeds, lower than 0.6 m/s, it is not necessary to include statically unstable phases. The shift of the centre of gravity towards and across the leading stability edge can result in getting into the dynamically unstable state. Considering the results we can effectively introduce two-point stance phases into crutch assisted FES walking and therefore increase the speed and energy effectiveness of walking  相似文献   
82.
Pain is traumatic for preterm infants and can damage their CNS. We wanted to assess whether multisensorial stimulation can be analgesic and whether this effect is only due to oral glucose or sucking. We performed a randomized prospective study, using a validated acute pain rating scale to assess pain during heel-prick combined with five different procedures: (A) control, (B) 10% oral glucose plus sucking, (C) sensorial saturation (SS), (D) oral water, and (E) 10% oral glucose. SS is a multisensorial stimulation consisting of delicate tactile, vestibular, gustative, olfactory, auditory and visual stimuli. Controls did not receive any analgesia. We studied 85 heel-pricks (5 per baby) performed for routine blood samples in 17 preterm infants (28-35 weeks of gestational age). We applied in random order in each patient the five procedures described above and scored pain. SS and sucking plus oral glucose have the greater analgesic effect with respect to no intervention (p < 0.001). The effect of SS is statistically better than that of glucose plus sucking (p < 0.01). SS promotes interaction between nurse and infant and is a simple effective form of analgesia for the NICU.  相似文献   
83.
AIM: To assess inter-observer reliability of two of the most widely used pain scales for newborns. BACKGROUND: More than 30 scales exist to assess neonatal pain, but they are rarely used because they are too complicated or unreliable. METHOD: We scored pain level in two groups of babies during a heelprick. The first group of 20 premature babies (mean gestational age: 34.2+/-1.2 weeks) was studied using the PIPP scale, and the second group of 20 term babies (mean gestational age: 39.5+/-0.9 weeks) with the NIPS scale. We compared the pain scores assigned by the nurse who took the blood sample (nurse A) and those assigned by another who was present during heelprick (nurse B) with those assigned by a nurse who later watched the video clip of the procedure (nurse C). We chose the latter as "objective" score, because in this case the scorer could watch the recorded event several times, timing and scoring it thoroughly. FINDING: NIPS: 8/20 scores were different between nurse A and nurse C, but only in one case was this difference greater than 2 (Cohen's K=0.60). In the case of nurse B, there were 12/20 differences with respect to the score assigned by nurse C but only one baby was assigned a score that differed by more than 2 (Cohen's K=0.30). PIPP: 16/20 scores were different between nurse A and nurse C; in 9 cases this difference was more than 2 (Cohen's K=0.10). In the case of nurse B, differences with respect to the score assigned by nurse C occurred in 17/20 cases and for six babies the difference in score was more than 2 (Cohen's K=0.16). CONCLUSION: Our results indicate a higher inter-observer reliability of NIPS than PIPP, though NIPS did not have a very high inter-observer agreement score. Caregivers who use them to assess pain in real time at the cribside should be aware of the limits we have highlighted in this study.  相似文献   
84.
Osteoarthritis (OA) is the most common joint disease, characterized by matrix degradation and changes in chondrocyte morphology and metabolism. Literature reported that electromagnetic fields (EMFs) can produce benefits in OA patients, even if EMFs mechanism of action is debated. Human osteoarthritic chondrocytes isolated from femoral heads were cultured in vitro in bidimensional (2-D) flasks and in three-dimensional (3-D) alginate beads to mimic closely cartilage environment in vivo. Cells were exposed 30 min/day for 2 weeks to extremely low-frequency electromagnetic field (ELF) with fixed frequency (100 Hz) and to therapeutic application of musically modulated electromagnetic field (TAMMEF) with variable frequencies, intensities, and waveforms. Cell viability was measured at days 7 and 14, while healthy-cell density, heavily vacuolized (hv) cell density, and cluster density were measured by light microscopy only for 3-D cultures after treatments. Cell morphology was observed for 2-D and 3-D cultures by transmission electron microscopy (TEM). Chondrocyte exposure to TAMMEF enhances cell viability at days 7 and 14 compared to ELF. Light microscopy analysis showed that TAMMEF enhances healthy-cell density, reduces hv-cell density and clustering, compared to ELF. Furthermore, TEM analysis showed different morphology for 2-D (fibroblast-like) and 3-D (rounded shape) cultures, confirming light microscopy results. In conclusion, EMFs are effective and safe for OA chondrocytes. TAMMEF can positively interfere with OA chondrocytes representing an innovative non-pharmacological approach to treat OA.  相似文献   
85.
Increased plasma osmolality by food intake evokes augmentation of plasma oxytocin (OT). Ovarian steroids may also influence the balance of body fluids by acting on OT neurones. Our aim was to determine if estrogen influences the activity of OT neurones in paraventricular nucleus (PVN) and supraoptic nucleus (SON) under different osmotic situations. Ovariectomized rats (OVX) were treated with either estradiol (E(2)) or vehicle and were divided into three groups: group I was fed ad libitum, group II underwent 48?h of fasting, and group III was refed after 48?h of fasting. On the day of the experiment, blood samples were collected to determine the plasma osmolality and OT. The animals were subsequently perfused, and OT/FOS immunofluorescence analysis was conducted on neurones in the PVN and the SON. When compared to animals which were fasted or fed ad libitum, the plasma osmolality of refed animals was higher, regardless of whether they were treated with vehicle or E(2). We observed neural activation of OT cells in vehicle- or E(2)-treated OVX rats refed after 48?h of fasting, but not in animals fed ad libitum or in animals that only underwent 48?h of fasting. Finally, the percentage of neurones that co-expressed OT and FOS was lower in both the PVN and the SON of animals treated with E(2) and refed, when compared to vehicle-treated animals. These results suggest that E(2) may have an inhibitory effect on OT neurones and may modulate the secretion of OT in response to the increase of osmolality induced by refeeding.  相似文献   
86.

Background:

Data from over 4 decades have reported a higher incidence of silent infarction among patients with diabetes mellitus (DM), but recent publications have shown conflicting results regarding the correlation between DM and presence of pain in patients with acute coronary syndromes (ACS).

Objective:

Our primary objective was to analyze the association between DM and precordial pain at hospital arrival. Secondary analyses evaluated the association between hyperglycemia and precordial pain at presentation, and the subgroup of patients presenting within 6 hours of symptom onset.

Methods:

We analyzed a prospectively designed registry of 3,544 patients with ACS admitted to a Coronary Care Unit of a tertiary hospital. We developed multivariable models to adjust for potential confounders.

Results:

Patients with precordial pain were less likely to have DM (30.3%) than those without pain (34.0%; unadjusted p = 0.029), but this difference was not significant after multivariable adjustment, for the global population (p = 0.84), and for subset of patients that presented within 6 hours from symptom onset (p = 0.51). In contrast, precordial pain was more likely among patients with hyperglycemia (41.2% vs 37.0% without hyperglycemia, p = 0.035) in the overall population and also among those who presented within 6 hours (41.6% vs. 32.3%, p = 0.001). Adjusted models showed an independent association between hyperglycemia and pain at presentation, especially among patients who presented within 6 hours (OR = 1.41, p = 0.008).

Conclusion:

In this non-selected ACS population, there was no correlation between DM and hospital presentation without precordial pain. Moreover, hyperglycemia correlated significantly with pain at presentation, especially in the population that arrived within 6 hours from symptom onset.  相似文献   
87.
Triclocarban (TCC) is an antimicrobial compound widely used in personal care products such as soaps, toothpaste, and shampoo. This agent is incompletely removed by wastewater treatment and represents an environmental contaminant. Recent studies have shown that TCC is associated with some endocrine disruptions. The aim of the present study was to evaluate if TCC exposure during critical periods of development (gestation and lactation) could lead to adverse effects on reproductive and behavior parameters of female offspring. Pregnant female Wistar rats were divided into four groups (n = 8–11/group): Control; TCC 0.3 mg/kg (TCC 0.3); TCC 1.5 mg/kg; TCC 3.0 mg/kg (TCC 3.0); and treated daily by oral gavage from gestational day 0 to lactational day 21. The female pups (F1 generation) were weaned on post-natal day 21 and included in the study. No litter-mates were used for the same group. There was a decrease in estradiol levels in the TCC 0.3 and TCC 3.0 groups. Moreover, there was a decrease in progesterone levels and an increase in pre-implantation loss in the TCC 3.0 group in adulthood. It is suggested, in this study, that the decrease in progesterone biosynthesis could interfere with implantation process. The exposure window to TCC is an important factor, as we found alterations only in the offspring.  相似文献   
88.
Abstract: The influence of functional electrically stimulated ankle plantar flexors on the swinging lower extremity was studied in incomplete spinal cord injured persons. Stimulation sequences with different time and frequency parameters were delivered to ankle plantar flexors and knee extensors and to the peroneal nerve. The results of kinematic assessment showed that stimulated calf muscles provide noticeable forward and upward propulsion to the swinging leg.  相似文献   
89.
The purpose of the study was to present a method for the assessment of finger joint torques in two‐fingered precision grips. The static analysis of various grips is important for the analysis of the mechanics of a human hand and the functional evaluation of grasping. We have built a grip‐measuring device assessing the endpoint forces of two‐oppositional grips. Through the simultaneous use of an optical measuring system and the grip‐measuring device, the finger positions and the grip force acting on the object were obtained. A recursive computational method was used within the proposed static model of the finger to calculate the finger joint torques. In the paper a three‐dimensional static model of the grip is presented and the calculated finger joint torques are shown. The repeatability within subject is analyzed for the assessed grip force and finger joint torques. The estimated joint torques corresponds to the amount of load on the finger joints during the isometric muscle contraction in nippers pinch.  相似文献   
90.
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