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PURPOSE: The aim of the present investigation was to evaluate the transverse displacement of the proximal segment and ramus rotation after a bilateral sagittal osteotomy (BSO) with rigid internal fixation (RIF) using bicortical LAG screws. PATIENTS AND METHODS: We conducted a retrospective review of 37 patients (14 males and 23 females, age range of 14 to 55 years) who underwent a mandibular advancement with BSO and RIF. Posteroanterior and lateral cephalometric radiographs were obtained 1 to 8 weeks before and 1 to 4 weeks after surgery. The transverse displacement and angulation of the proximal segments after surgery were measured on posteroanterior radiographs, using the best-fit method. The amount of mandibular advancement was compared with the amount of transverse displacement of the proximal segments. RESULTS: In the 1 to 4-week postoperative period after a BSO, 36 of 37 subjects showed an increased transverse intergonion distance (5.6 mm) (P <.0001) and 35 of 37 patients showed an increased transverse interramus width (3.3 mm) (P <.0001). No correlation was found between mandibular advancement and transverse displacement of the proximal segment. CONCLUSIONS: The study results indicate that transverse displacements of the proximal segments occur with BSO and RIF. The clinical impact on temporomandibular joint symptomatology or surgical relapse with such displacement was not assessed in the study. Future studies that address these issues may help to determine whether there is an association between proximal segment displacement and surgical relapse, temporomandibular dysfunction, or both.  相似文献   
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Myotonic dystrophy or dystrophia myotonica (DM) is a hereditary neuromuscular multisystem disease with a varying clinical expressivity and severity. The objective of this study was to assess the oral health in children with myotonic dystrophy and to compare it with a control group. Fifty-six DM patients, aged 2.7-18.0 yr, were compared with age- and gender-matched control patients with respect to caries, plaque, and gingivitis. Oral function and signs of temporomandibular dysfunction (TMD) were assessed, and the ability to co-operate in dental treatment was estimated. Questionnaires concerning eating habits, dental care, traumatic injuries to teeth, and orofacial function were also used. The DM patients had significantly more caries, plaque, and gingivitis than did control patients. They had more TMD problems and lower co-operation ability than the healthy control persons. General sedation was frequently needed to carry through dental treatment. DM patients are at risk of caries, gingivitis and TMD problems, and need intensified prophylactic care. Behavior management problems are common.  相似文献   
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Coronavirus disease 2019 (COVID-19) is a pandemic touching thousands of people all around the world. Patients supported with left ventricular assist devices (LVADs) are affected by long-standing cardiovascular diseases and subjected to variations of the normal cardiovascular physiology, thus requiring an even closer monitoring during the COVID-19 outbreak. Nevertheless, the COVID-19 pandemic led to a drastic reduction in routine clinical activities and a consequent risk of looser connections between LVAD patients and their referring center. Potential deleterious effects of such a situation can be a delayed recognition of LVAD-related complications, misdiagnosis of COVID-19, and impaired social and psychological well-being for patients and families. As one of the largest LVAD programs worldwide, we designed a sustainable and enforceable telemonitoring algorithm which can be easily adapted to every LVAD center so as to maintain optimal quality of care for LVAD patients during the COVID-19 pandemic.  相似文献   
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Aim of the study

Hypothermia treatment with cold intravenous infusion and ice packs after cardiac arrest has been described and used in clinical practice. We hypothesised that with this method a target temperature of 32-34 °C could be achieved and maintained during treatment and that rewarming could be controlled.

Materials and methods

Thirty-eight patients treated with hypothermia after cardiac arrest were included in this prospective observational study. The patients were cooled with 4 °C intravenous saline infusion combined with ice packs applied in the groins, axillae, and along the neck. Hypothermia treatment was maintained for 26 h after cardiac arrest. It was estimated that passive rewarming would occur over a period of 8 h. Body temperature was monitored continuously and recorded every 15 min up to 44 h after cardiac arrest.

Results

All patients reached the target temperature interval of 32-34 °C within 279 ± 185 min from cardiac arrest and 216 ± 177 min from induction of cooling. In nine patients the temperature dropped to below 32 °C during a period of 15 min up to 2.5 h, with the lowest (nadir) temperature of 31.3 °C in one of the patients. The target temperature was maintained by periodically applying ice packs on the patients. Passive rewarming started 26 h after cardiac arrest and continued for 8 ± 3 h. Rebound hyperthermia (>38 °C) occurred in eight patients 44 h after cardiac arrest.

Conclusions

Intravenous cold saline infusion combined with ice packs is effective in inducing and maintaining therapeutic hypothermia, with good temperature control even during rewarming.  相似文献   
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CD4+CD25+ regulatory T cells (T reg cells) play a key role in controlling autoimmunity and inflammation. Therefore, therapeutic agents that are capable of elevating numbers or increasing effector functions of this T cell subset are highly desirable. In a previous report we showed that a superagonistic monoclonal antibody specific for rat CD28 (JJ316) expands and activates T reg cells in vivo and upon short-term in vitro culture. Here we demonstrate that application of very low dosages of the CD28 superagonist into normal Lewis rats is sufficient to induce T reg cell expansion in vivo without the generalized lymphocytosis observed with high dosages of JJ316. Single i.v. administration of a low dose of the CD28 superagonist into Dark Agouti (DA) rats or Lewis rats that suffered from experimental autoimmune encephalomyelitis (EAE) proved to be highly and equally efficacious as high-dose treatment. Finally, we show that T reg cells that were isolated from CD28-treated animals displayed enhanced suppressive activity toward myelin basic protein-specific T cells in vitro, and, upon adoptive transfer, protected recipients from EAE. Our data indicate that this class of CD28-specific monoclonal antibodies targets CD4+CD25+ T reg cells and provides a novel means for the effective treatment of multiple sclerosis and other autoimmune diseases.  相似文献   
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Objectives: Artificial colloids, frequently used to prevent hemorrhagic shock in children, impair blood coagulation. To determine the impact of acute isovolaemic hemodilution with artificial colloids on clot formation, we conducted an experimental study in a pediatric animal model. Methods: Fifteen piglets underwent hemorrhage by withdrawing 40 ml·kg?1 of blood volume in steps of 10 ml·kg?1 each within 1 hour. After each withdrawal, the blood loss was randomly compensated by administering 4% gelatin (GEL) or hydroxylethyl starch 130/0.42 (HES) in a ratio of 1 : 1, or isotonic crystalloid solution (ICS) in a ratio of 1 : 4 for isovolaemic hemodilution. Quality of clot formation and platelet function was measured using Thrombelastometry (ROTEM®) and Multiple electrode impedance aggregometry (Multiplate®) after 10, 20, and 40 ml·kg?1 blood replacement. Results: Moderate hemodilution (10–20 ml·kg?1 blood replacement) caused no significant differences among groups (e.g. INTEM®‐MCF after 20 ml·kg?1 blood replacement (ICS vs GEL vs HES, P > 0.05). Profound hemodilution with 40 ml·kg?1 blood replacement showed a significant difference between ICS and both colloids (P < 0.05), but no significant differences between GEL and HES. Conclusions: Impairment of clot formation by moderate isovolaemic hemodilution did not significantly differ between ICS, GEL, and HES. Profound hemodilution of more than 50% of the estimated blood volume with GEL and HES caused significant impairment of clot formation in comparison to ICS and has to be considered when using high amounts of these synthetic colloids.  相似文献   
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Experimental results are presented demonstrating the application of pulse echo ultrasound to imaging the skin. A laboratory prototype B-mode mechanical scanner was employed to obtain images of human skin, both in vitro and in vivo, using broadband pulsed ultrasound at 25 MHz. Images were formed by processing digitized A-mode waveforms and displaying the resulting two-dimensional cross sections using a digital imaging system. Images obtained by rectifying the A-modes are compared to those derived using a software-based cross-correlation technique. Scans of test targets demonstrate that an axial resolution of 100 m can be achieved at 25 MHz when the digital correlation method is employed. Lateral resolution is limited by the 0.25 mm half-power focal beamwidth of the transducer. Seventeen in vitro ultrasonic scans of human skin were compared to frozen section histology. Average skin depth was well correlated between the two techniques ( = 0.99, p less than 0.001). Application of cross-correlated processing to 25 MHz in vivo images produced good delineation of epidermis, papillary, and reticular dermis. Conversion to a 50 MHz transducer did not delineate skin layers as well as the 25 MHz transducer due to inherent difficulties with transducer reverberations.  相似文献   
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