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1.
The small external fixator can be used in the treatment of injuries of the wrist and the distal forearm.This fixator is indicated especially when an unstable fracture needs to be treated, when the bone concerned is affected by osteoporosis in an elderly patient,and in the early treatment of polytraumatized patients with severe soft tissue injuries.For reduction of the fracture we prefer the modular three-tube technique, which is very gentle on the soft tissue; in addition we use the advantages of ligamentotaxis.Depending on the fracture type,we use the small external fixator alone or in association with an internal osteosynthesis.With scrupulous followup checks in the outpatient clinic loosening of the Schanz screws and infection around them are very rare.  相似文献   
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Summary The kinetics of a single 5-mg oral dose of the thienodiazepine clotiazepam was evaluated in a series of patients with biopsy-proven cirrhosis, and in patients with renal insufficiency requiring maintenance hemodialysis, compared to healthy matched controls. Clotiazepam volume of distribution (Vz) was significantly smaller in cirrhotic patients than in controls (1.83 vs 2.57 l/kg), and total clearance was likewise reduced (2.15 vs 3.15 ml/min/kg). Elimination half-life was similar between groups (10.0 vs. 10.2h). There were no significant differences between renal failure and control patients in clotiazepam Vz, oral clearance, or elimination half-life. Thus cirrhosis is associated with reduced clearance of clotiazepam, probably due to impairment of its microsomal oxidation. However clotiazepam disposition is not significantly altered in dialysis-dependent renal insufficiency patients.Supported in part by Grant OC 10/6–4 from Deutsche Forschungsgemeinschaft, and Grant MH-34223 from the United States Public Health Service.  相似文献   
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We describe a 12-year-old boy with Wiskott-Aldrich syndrome who developed a pulmonary vasculitis associated with lymphoreticular proliferation, consistent with the histological and clinical diagnosis of lymphomatoid granulomatosis. The lesions were responsive to cyclophosphamide and steroids. The patient has had severely depressed immune function and was shown to have abnormal Epstein-Barr virus (EBV)-specific cellular and humoral immune responses. Lymph nodes obtained at autopsy were positive for EBV genome. In this patient, reactivated EBV infection resulting from impaired immune surveillance of the virus may have been responsible for the development of this paraneoplastic disorder.  相似文献   
6.
Alterations in pulmonary surfactant have been reported to be associated with ischemia/reperfusion injury in experimental and clinical lung transplantation. It is unknown whether these alterations are due to damage to surfactant synthesizing type II pneumocytes during hypothermic ischemic storage. The aim of the present study was to examine the effects of hypothermic ischemic storage of the lung on canine type II pneumocytes by means of conventional (CTEM) and energy filtering TEM (EFTEM) and stereology. The lungs of 18 dogs were fixed for TEM immediately after cardiac arrest (6 double lungs) and after storage in Tutofusin at 4 degrees C for 20 min, 4 hr, 8 hr, and 12 hr (6 single lungs, respectively). Using a systematic uniform random sampling scheme, type II pneumocytes were analyzed qualitatively and stereologically. The relative phosphorus content of cell organelles, especially the surfactant containing lamellar bodies, was investigated by EFTEM. By CTEM, no major qualitative alterations could be observed in type II pneumocytes of the experimental groups. Stereologically, no significant changes in the volume densities or the volume-to-surface ratios of type II pneumocytes and their lamellar bodies were found. By EFTEM, the highest intracellular phosphorus signals were recorded over lamellar bodies in all experimental groups. No changes in the phosphorus signals were observed during ischemia. These results indicate that the ultrastructure of canine type II pneumocytes and their lamellar bodies is not affected by hypothermic ischemia of the lung up to 12 hr. Structural preservation of intracellular surfactant is possible during prolonged ischemic lung storage.  相似文献   
7.
Autoimmune disorders are reportedly more frequent than expected in immunodeficient patients and in their relatives. The hypothesis that genetic factors related to immunodeficiency may predispose to the development of autoimmunity was studied in relatives of patients with variable immunodeficiency (VID), ataxia-telangiectasia (A-T), or X-linked infantile agammaglobulinaemia (X-LA). Close relatives of patients with VID or A-T had thyroid and gastric autoantibodies significantly more frequently than did control subjects. No abnormalities were detected in unaffected relatives of X-LA patients. The increased incidence of organ-specific autoantibodies in close relatives of VID patients was confined to those families with more than one member with immunodeficiency. These data suggest that there are at least two forms of VID, one of which is associated with familial autoimmunity. It is postulated that heterozygous carriers of the A-T gene and persons with genes involved in the development of VID may exhibit T-lymphocyte dysfunction which predisposes them to autoimmunity.  相似文献   
8.
Summary The pharmacokinetics of a single 30-mg oral dose of oxazepam was evaluated in seven patients with chronic renal failure on maintenance hemodialysis and in seven healthy controls matched for age and sex. Based on total (free plus bound) serum oxazepam concentrations, elimination half-life was prolonged in renal patients compared to controls (22 vs 8 h,p<0.001) and volume of distribution increased (3.0 vs 1.4 1/kg,p<0.02). However, total clearance was similar between groups (1.8 vs 1.9 ml/min per kilogram). These findings were confounded by the increased oxazepam free fraction in serum of renal failure patients (10.3%) as compared to healthy controls (4.3%). Correction for differences in binding indicates similar distribution of unbound oxazepam between groups, but reduced clearance of pharmacologically active unbound oxazepam in renal patients (18 vs 45 ml/min per kilogram). Oxazepam dosage, therefore, may require downward adjustment for renal failure patients on hemodialysis.Supported in part by grant OC 10/6-3 from the Deutsche Forschungsgemeinschaft, and by grant MH-34223 from the United States Public Health Service  相似文献   
9.
The diagnosis of acute infection with Trypanosoma cruzi, the protozoan parasite that causes Chagas' disease, is generally made by detecting parasites by microscopic examination of fresh blood. Although highly specific, this approach often lacks sensitivity. Several years ago, PCR assays for the detection of T. cruzi were described, but the sensitivities and specificities of these tests have not yet been defined precisely. In the present study, we first compared the sensitivities of PCR methods that differ in sample processing as well as in the target sequences that are amplified. Then, we challenged eight mice with T. cruzi, and on 31 days over a 380-day period, we compared the ability of the PCR method with the highest sensitivity to detect parasites in blood with that of microscopic examination. During the acute phase of the infections, parasites were detected on average 3.9 days earlier by the PCR method than by microscopy. Furthermore, the infected mice were consistently positive by the PCR method during the chronic phase, while parasites were intermittently detected by microscopic examination during that period. Overall, among the 248 comparisons, in 84 the PCR method was positive and no parasites were seen by microscopic examination, whereas the reverse was true in only 1 case, a difference that is highly significant. These findings suggest that this approach should be in patients suspected of having acute Chagas' disease. Moreover, the higher sensitivity of the PCR method observed in both the acute and chronic phases of the T. cruzi infections in the mice that we studied indicates that this approach should be useful in evaluating experimental drugs in T. cruzi-infected laboratory animals.  相似文献   
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1. Multiple microelectrode maps of the hand representation within and across the borders of cortical area 3b were obtained before, immediately after, or several weeks after a period of behaviorally controlled hand use. Owl monkeys were conditioned in a task that produced cutaneous stimulation of a limited sector of skin on the distal phalanges of one or more fingers. 2. Analysis of microelectrode mapping experiment data revealed that 1) stimulated skin surfaces were represented over expanded cortical areas. 2) Most of the cutaneous receptive fields recorded within these expanded cortical representational zones were unusually small. 3) The internal topography of representation of the stimulated and immediately surrounding skin surfaces differed greatly from that recorded in control experiments. Representational discontinuities emerged in this map region, and "hypercolumn" distances in this map sector were grossly abnormal. 4) Borders between the representations of individual digits and digit segments commonly shifted. 5) The functionally defined rostral border of area 3b shifted farther rostralward, manifesting either an expansion of the cutaneous area 3b fingertip representation into cortical field 3a or an emergence of a cutaneous input zone in the caudal aspect of this normally predominantly deep-receptor representational field. 6) Significant lateralward translocations of the borders between the representations of the hand and face were recorded in all cases. 7) The absolute locations--and in some cases the areas or magnifications--of representations of many skin surfaces not directly involved in the trained behavior also changed significantly. However, the most striking areal, positional, and topographic changes were related to the representations of the behaviorally stimulated skin in every studied monkey. 3. These experiments demonstrate that functional cortical remodeling of the S1 koniocortical field, area 3b, results from behavioral manipulations in normal adult owl monkeys. We hypothesize that these studies manifest operation of the basic adaptive cortical process(es) underlying cortical contributions to perception and learning.  相似文献   
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