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21.
This study is aimed at reviewing the existing literature about children with cancer and their families in order to identify themes that have been researched and to survey indicators of need, thus giving subsidies for the systematization of nursing care. Systemized data collection was carried out in computerized databases between 1997 and 2002 using the keywords child, cancer, chronic illness/disease, family and nursing. A non-systemized research of scientific publications was also carried out. Results are grouped in three themes: impact of the child's cancer on the family system; adaptation process and coping strategies used by the parents in the face of the illness; and the process of loss and mourning in view of the child's death. The review demonstrated that nursing is constructing specific knowledge about the individual, cultural and regional needs of families of children with cancer, with a view to a nursing assistance that considers care in accordance to the singularity of each case.  相似文献   
22.
To assess the epidemiology of hepatitis B virus (HBV) infection among men who have sex with men (MSM) in Peru, we evaluated the prevalence and associated risk factors for HBV serologic markers among participants of a HIV sentinel surveillance conducted in 2002–2003. The standardized prevalences for total antibodies to hepatitis B core antigen (anti-HBc) and hepatitis B surface antigen (HBsAg) were 20.2% and 2.8%, respectively. Individuals with human immunodeficiency virus (HIV-1) infection had significantly higher anti-HBc (44.3% versus 19.3%) and HBsAg (9.5% versus 2.3%) prevalences than uninfected men. Increasing age (adjusted odds ratio [AOR] = 1.06), versatile sexual role (AOR = 1.59), sex in exchange for money/gifts (AOR = 1.58), syphilis (AOR = 1.74), HIV-1 infection (AOR = 1.64), and herpes simplex virus type 2 (HSV-2, AOR = 2.77) infection were independently associated with anti-HBc positivity, whereas only HIV-1 infection (AOR = 3.51) and generalized lymph node enlargement (AOR = 3.72) were associated with HBsAg positivity. Pre-existing HBV infection is very common among Peruvian MSM and was correlated with sexual risk factors. MSM in Peru constitute a target population for further HBV preventive and treatment interventions.  相似文献   
23.
BACKGROUND: Convulsive status epilepticus (CSE) is the most common neurological emergency in childhood and is often associated with fever. In sub-Saharan Africa, the high incidence of febrile illnesses might influence the incidence and outcome of CSE. We aimed to provide data on the incidence, causes, and outcomes of childhood CSE in this region. METHODS: Between March, 2006, and June, 2006, we studied all children who had been admitted with CSE to a Kenyan rural district hospital in 2002 and 2003. Confirmed CSE had been observed directly; probable CSE was inferred from convulsions on arrival, requirement for phenobarbital or phenytoin, or coma with a recent history of seizures. We estimated the incidence with linked demographic surveillance, and risk factors for death and neurological sequelae were analysed by multivariable analysis. FINDINGS: Of 388 episodes of CSE, 155 (40%) were confirmed CSE and 274 (71%) were caused by an infection. The incidence of confirmed CSE was 35 (95% CI 27-46) per 100,000 children per year overall, and was 52 (21-107) and 85 (62-114) per 100,000 per year in children aged 1-11 months and 12-59 months, respectively. The incidence of all CSE was 268 (188-371) and 227 (189-272) per 100,000 per year in these age-groups. 59 (15%) children died in hospital, 81 (21%) died during long-term follow-up, and 46 (12%) developed neurological sequelae. Mortality of children with confirmed CSE while in hospital was associated with bacterial meningitis (adjusted relative risk [RR]=2.6; 95% CI 1.4-4.9) and focal onset seizures (adjusted RR=2.4; 1.1-5.4), whereas neurological sequelae were associated with hypoglycaemia (adjusted RR=3.5; 1.8-7.1) and age less than 12 months (adjusted RR=2.5; 1.2-5.1). INTERPRETATION:Prevention of infections and appropriate early management of seizures might reduce the incidence and improve the outcome of CSE in children in sub-Saharan Africa.  相似文献   
24.
The aim of the present study was to determine the effects of fetal asphyxia (FA) on anxiety and serotonergic neurons in young adult and middle-aged rats. FA was induced at embryonic day 17 by clamping the uterine circulation for 75 min. Anxiety-related behavior was tested in an open field, and design-based stereology was used for counting serotonergic (5-hydroxytryptamine/serotonin, 5-HT) neurons in the dorsal raphe nucleus (DRN). The open field revealed increased anxiety in the 19-month-old FA rats in comparison to control animals. No significant differences were found in DRN 5-HT neuron numbers at 6 months. At 19 months, however, FA significantly lowered the mean density and volume of 5-HT neurons in the DRN as compared to controls. Further, an age-related reduction was found in the total number, the mean density and the mean volume of 5-HT neurons within the FA group. In conclusion, FA is associated with increased anxiety and age-related changes in 5-HT immunohistochemistry within the DRN. These results support the notion that insults caused by asphyxiation during critical periods of brain development could create a predisposition to serotonergic abnormalities and anxiety deficits in adulthood.  相似文献   
25.
Background  The decision to proceed to simple underwater seal drainage or apply active suction to the underwater seal after lung resection is mostly based on surgeon preference. The purpose of this study was to test whether routine application of active suction is necessary after lobectomy. Patients and methods  This was a prospective randomized controlled trial conducted in the Patras University Hospital. Ninety-one patients who underwent lobectomy or bilobectomy for lung cancer and met the eligibility criteria were enrolled. Group I included 47 patients and group II had 44 patients. The two groups were comparable. At the end of surgical procedure patients were randomly assigned to receive −15 to −20 cm H2O active suction applied to the underwater seal drainage (group I) or simple underwater seal drainage (group II). The primary end point was the time elapsed between placement and removal of drains. Results  No statistically significant differences were observed between the two groups in terms of time elapsed between the removal of chest drains, mortality, morbidity, adequacy of drainage system, and postoperative hospital stay. Suction applied to the underwater seal to re-expand the lung succeeded in 3 of 10 cases of persistent pneumothorax in group II. Discontinuing suction in 7 patients with persistent air leak in group I resulted in leak resolution in 4 patients. Conclusions  Routine application of active drain suction to the underwater seal is not necessary after lobectomy. However, it could be useful in persistent pneumothorax with sufficient air entry in the lung and clear airways. It is of no help in persistent air leaks when the lung is expanded.  相似文献   
26.
The facultative intracellular pathogen Salmonella enterica resides in a specific membrane-bound compartment termed the Salmonella-containing vacuole (SCV). Despite being segregated from access to metabolites in the host cell cytosol, Salmonella is able to efficiently proliferate within the SCV. We set out to unravel the nutritional supply of Salmonella in the SCV with focus on amino acids. We studied the availability of amino acids by the generation of auxotrophic strains for alanine, asparagine, aspartate, glutamine, and proline in a macrophage cell line (RAW264.7) and an epithelial cell line (HeLa) and examined access to extracellular nutrients for nutrition. Auxotrophies for alanine, asparagine, or proline attenuated intracellular replication in HeLa cells, while aspartate, asparagine, or proline auxotrophies attenuated intracellular replication in RAW264.7 macrophages. The different patterns of intracellular attenuation of alanine- or aspartate-auxotrophic strains support distinct nutritional conditions in HeLa cells and RAW264.7 macrophages. Supplementation of medium with individual amino acids restored the intracellular replication of mutant strains auxotrophic for asparagine, proline, or glutamine. Similarly, a mutant strain deficient in succinate dehydrogenase was complemented by the extracellular addition of succinate. Complementation of the intracellular replication of auxotrophic Salmonella by external amino acids was possible if bacteria were proficient in the induction of Salmonella-induced filaments (SIFs) but failed in a SIF-deficient background. We propose that the ability of intracellular Salmonella to redirect host cell vesicular transport provides access of amino acids to auxotrophic strains and, more generally, is essential to continuously supply bacteria within the SCV with nutrients.  相似文献   
27.
28.
This study evaluated the lymphatic density and HIF-1α immunoexpression in lower lip squamous cell carcinoma (LLSCC) and their correlation with clinicopathological (nodal metastasis, clinical stage, histological grade, recurrence and disease outcome) and survival parameters in 20 metastatic and 20 non-metastatic LLSCCs. Lymphatic density was established by counting microvessels (D2-40+) at the tumor core (intratumoral lymphatic density, ILD) and at the invasive front (peritumoral lymphatic density, PLD) and percentages of immunopositive cells for HIF-1α were established. No statistically significant differences in lymphatic densities in relation to clinicopathological parameters were observed (P > 0.05). All cases exhibited nuclear and cytoplasmic HIF-1α immunoexpression, with relatively high percentages of positivity, but this expression was not statistically different in relation to clinicopathological variables (P > 0.05). Positive correlations were observed between ILD and PLD (P = 0.002), and between nuclear HIF-1α immunoexpression at the tumor core and ILD (P = 0.001). The results suggest ILD and PLD are not directly related to the development of lymph node metastasis in LLSCC. The striking expression of HIF-1α suggests the involvement of this protein in the etiopathogenesis of LLSCCs, possibly stimulating lymphangiogenesis at the tumor core. However, this protein does not seem to exert a determining influence on the biological aggressiveness of these tumors.  相似文献   
29.

Purpose

A ceramic and metal abutment prototype was fatigue tested to determine the probability of survival at various loads.

Materials and Methods

Lithium disilicate CAD‐milled abutments (n = 24) were cemented to titanium sleeve inserts and then screw attached to titanium fixtures. The assembly was then embedded at a 30° angle in polymethylmethacrylate. Each (n = 24) was restored with a resin‐cemented machined lithium disilicate all‐ceramic central incisor crown. Single load (lingual‐incisal contact) to failure was determined for three specimens. Fatigue testing (n = 21) was conducted employing the step‐stress method with lingual mouth motion loading. Failures were recorded, and reliability calculations were performed using proprietary software. Probability Weibull curves were calculated with 90% confidence bounds. Fracture modes were classified with a stereomicroscope, and representative samples imaged with scanning electron microscopy.

Results

Fatigue results indicated that the limiting factor in the current design is the fatigue strength of the abutment screw, where screw fracture often leads to failure of the abutment metal sleeve and/or cracking in the implant fixture. Reliability for completion of a mission at 200 N load for 50K cycles was 0.38 (0.52% to 0.25 90% CI) and for 100K cycles was only 0.12 (0.26 to 0.05)—only 12% predicted to survive. These results are similar to those from previous studies on metal to metal abutment/fixture systems where screw failure is a limitation. No ceramic crown or ceramic abutment initiated fractures occurred, supporting the research hypothesis. The limiting factor in performance was the screw failure in the metal‐to‐metal connection between the prototyped abutment and the fixture, indicating that this configuration should function clinically with no abutment ceramic complications.

Conclusion

The combined ceramic with titanium sleeve abutment prototype performance was limited by the fatigue degradation of the abutment screw. In fatigue, no ceramic crown or ceramic abutment components failed, supporting the research hypothesis with a reliability similar to that of all‐metal abutment fixture systems. A lithium disilcate abutment with a Ti alloy sleeve in combination with an all‐ceramic crown should be expected to function clinically in a satisfactory manner.  相似文献   
30.

Background:

Isokinetic dynamometry allows the measurement of several variables related to muscular performance, many of which are seldom used, while others are redundantly applied to the characterization of muscle function.

Objectives:

The present study aimed to establish the particular features of muscle function that are captured by the variables currently included in isokinetic assessment and to determine which variables best represent these features in order to achieve a more objective interpretation of muscular performance.

Method:

This study included 235 male athletes. They performed isokinetic tests of concentric knee flexion and extension of the dominant leg at a velocity of 60º/s. An exploratory factor analysis was performed.

Results:

The findings demonstrated that isokinetic variables can characterize more than muscle torque production and pointed to the presence of 5 factors that enabled the characterization of muscular performance according to 5 different domains or constructs.

Conclusions:

The constructs can be described by torque generation capacity; variation of the torque generation capacity along repetitions; movement deceleration capacity; mechanical/physiological factors of torque generation; and acceleration capacity (torque development). Fewer than eight out of sixteen variables are enough to characterize these five constructs. Our results suggest that these variables and these 5 domains may lead to a more systematic and optimized interpretation of isokinetic assessments.  相似文献   
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