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41.
42.
OBJECTIVE: Hypovolemia after aneurysmal subarachnoid hemorrhage (SAH) may be mediated by natriuretic peptides and can further impair cerebral perfusion in dysautoregulated and vasospastic arterial territories. Dendroaspis natriuretic peptide (DNP), derived from the venom of Dendroaspis augusticeps, the Green Mamba snake, has recently been discovered in human plasma and atrial myocardium. There is no information regarding the presence or putative role of this peptide in patients with aneurysmal SAH. METHODS: A sensitive and specific DNP radioimmunoassay was performed on venous blood samples obtained on post-SAH Days 1, 3, and 7 from 10 consecutive SAH patients (cases) and randomly from 9 healthy volunteers (controls). Clinical and laboratory data, including daily serum sodium concentration and fluid balance, were collected prospectively up to 7 days after the ictus. RESULTS: Increase in plasma DNP levels occurred in five (63%) of eight patients who had DNP levels measured on Days 1 and 3 (mean increase, 29%). An increase in DNP level was significantly associated with development of a negative fluid balance (P = 0.003) and hyponatremia (P = 0.008). Three (75%) of the four patients who developed cerebral vasospasm during this study experienced an increase in DNP levels from Days 1 to 3. CONCLUSION: The present study is the first to find a significant association between elevated levels of DNP, a new member of the natriuretic peptide family, and the development of diuresis and natriuresis in patients with aneurysmal SAH. Our findings warrant further investigation by means of a large-scale, prospective, case-control study.  相似文献   
43.
Critical illness myopathy (CIM) which is common after sepsis and multiorgan failure also has been described after organ transplantation. Prior reports of CIM after lung transplantation have not recorded a necrotizing myopathy. We present a 42-year-old man who developed a necrotizing critical illness myopathy following bilateral orthotopic lung transplantation. In addition we provide pathological confirmation that the ventral roots, spinal cord and the rest of the neuraxis are preserved in this condition. Extensive muscle necrosis is documented.  相似文献   
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45.
Pulmonary complications of aneurysmal subarachnoid hemorrhage   总被引:5,自引:0,他引:5  
OBJECTIVE: Pulmonary complications challenge the medical management of patients who have sustained aneurysmal subarachnoid hemorrhage (SAH). We assessed the frequency and types of pulmonary complications after aneurysmal SAH and analyzed the impact of pulmonary complications on patient outcome. METHODS: We reviewed the records of all patients with acute SAH treated at our institution between 1990 and 1997. Three hundred five consecutive patients with an aneurysmal hemorrhage source documented by angiography and treated within 7 days of ictus were analyzed. Outcomes at longest follow-up (mean, 16 mo) were measured by use of the Glasgow Outcome Scale. RESULTS: Pulmonary complications were documented in 66 patients (22%). The pulmonary complications were nosocomial pneumonia in 26 patients (9%), congestive heart failure in 23 (8%), aspiration pneumonia in 17 (6%), neurogenic pulmonary edema in 5 (2%), pulmonary embolus in 2 (<1%), and other pulmonary disorders in 4 (1%); 11 patients had two pulmonary complications. The incidence of symptomatic vasospasm was greater in patients with pulmonary complications (63%) than in patients without pulmonary complications (31%) (P = 0.001), and this association was independent of age and clinical grade at admission (odds ratio, 3.68; P < 0.001). Overall clinical outcomes were worse in patients with pulmonary complications (mean Glasgow Outcome Scale score, 3.3) than in patients without pulmonary complications (mean Glasgow Outcome Scale score, 4.0; P = 0.0001), but pulmonary complications were not an independent predictor of worse outcome when adjusted for age and clinical grade at admission (odds ratio, 1.38; P = 0.315). CONCLUSION: Patients who experience pulmonary complications after aneurysmal SAH have a higher incidence of symptomatic vasospasm than do patients without pulmonary complications. This most likely reflects both the failure to maintain aggressive hypervolemic and hyperdynamic therapy in patients with pulmonary compromise and the possible precipitation of congestive heart failure by hypervolemic therapy in patients with preexisting delayed ischemic neurological deficit. Although patients with pulmonary complications have worse overall clinical outcomes than do patients without pulmonary complications, this is attributable to older age and worse clinical grades at admission.  相似文献   
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47.
OBJECTIVE: Supratentorial lobar hemorrhage can be devastating. Outcome prediction at presentation is important in triage and management decisions as well as appropriate resource utilization. We performed a decision tree analysis combining clinical and CT scan features to predict poor and hopeless outcome at initial presentation in patients with lobar hemorrhage. METHODS: We analyzed 81 patients with spontaneous lobar hemorrhage presenting within 48 hours of initial neurologic symptoms. In the first analysis, poor outcome was defined as Glasgow outcome score (GOS) of 1 (death), 2 (vegetative state) or 3 (dependence) at discharge. A second analysis was based on worst possible outcome (GOS 1-2). Binary recursive partitioning was fitted in a model, and odds ratios with 95% confidence intervals (CI) were calculated. RESULTS: Lobes involved were temporal (36%), parietal (33%), frontal (25%) and occipital (6%). Seventy-three percent of patients presented less than 17 h after initial ictus. The probability of poor outcome was 97% (CI 85-100%) in patients with hemorrhage greater than 40 cm(3). In the subset of patients with a volume less than 40 cm(3), time interval from ictus to presentation (< 17 h) together with a Glasgow coma score (GCS) less than or equal to 13 predicted poor outcome. Eighty-five percent (CI 42-99%) of those presenting early with GCS less than or equal to 13 had a poor outcome. In the second analysis, all patients with GCS less than or equal to 12 and septum pellucidum shift > 6 mm had GOS of 1 or 2 (CI 72-100%). CONCLUSION: Poor outcome in patients with lobar hemorrhage is associated with a hemorrhage size of more than 40 cm(3), GCS less than or equal to 13, but also dependent on time interval between ictus and presentation. This is consistent with prior studies demonstrating deterioration from enlargement may occur when patients present early on. Stupor and septum pellucidum shift greater than 6 mm on CT scan at presentation predict a hopeless outcome in conservatively treated patients. Ninety-one percent of patients were treated medically, thus these outcomes are largely a reflection of the natural history of spontaneous lobar hemorrhage. These signs may influence triage and management decisions.  相似文献   
48.
Schievink WI  Wijdicks EF  Meyer FB  Sonntag VK 《Neurosurgery》2001,48(3):513-6; discussion 516-7
OBJECTIVE: An excruciating headache of instantaneous onset is known as a thunderclap headache. A subarachnoid hemorrhage is the prototypical cause, but other serious disorders may also present with a thunderclap headache, including cerebral venous sinus thrombosis, carotid artery dissection, and pituitary apoplexy. We report a group of patients with thunderclap headaches as the initial manifestation of spontaneous intracranial hypotension caused by a spinal cerebrospinal fluid leak. METHODS: Among 28 patients with spontaneous intracranial hypotension due to a documented spinal cerebrospinal fluid leak, four (14%) initially experienced an excruciating headaches of instantaneous onset. RESULTS: The mean age of the four patients (two men and two women) was 35 years (range, 24-45 yr). Nuchal rigidity was present in the three patients who sought early medical attention, and they underwent emergency computed tomographic scanning, lumbar puncture, and cerebral angiography to rule out an aneurysmal subarachnoid hemorrhage. The delay between the onset of headache and diagnosis of intracranial hypotension ranged from 4 days to 5 weeks. A fourth patient did not seek medical attention until 1 month after the ictus. CONCLUSION: Spontaneous intracranial hypotension should be included in the differential diagnosis of thunderclap headache, even when meningismus is present.  相似文献   
49.
Chan  WC; Link  S; Mawle  A; Check  I; Brynes  RK; Winton  EF 《Blood》1986,68(5):1142-1153
Two major types of lymphocytosis of large granular lymphocytes (LGLs) were observed. The proliferating LGLs in each type had distinct immunophenotypes, functional characteristics, and probably belonged to different cell lineages. The more common form (Type A) consisted of cells derived from the T cell lineage and had the T suppressor/cytotoxic phenotype (T11+, T3+, T8+). The expression of the Leu 7 and HLA-DR antigen was variable. These cells did not have natural killer (NK) function but showed a variable degree of antibody-dependent cell-mediated cytotoxic (ADCC) activity. Neutropenia was invariably present and rheumatoid arthritis and autoantibodies were frequent associations. These lymphocytes had many similarities to the major type of LGLs present in normal adult bone marrow. The other type of LGL lymphocytosis (Type B) consisted of cells lacking the antigens T3 and T8 but expressing M1 and NKH1. These cells possessed strong NK and ADCC activity but their cell lineage was not clear. Neutropenia and autoimmune phenomena were not detected. The cytochemical characteristics of the LGL granules from both types of patients were similar but differences in ultrastructure were observed. LGLs from Type B patients proliferated in the presence of Interleukin 2 (IL-2) and 12- O-tetradecanoyl-phorbol-13 acetate (TPA). Significant changes in their basic T11+, T3-, T8- phenotype were not observed. IL-2 and TPA, however, had profound influence on the NK function of the cells with enhancement in the case of IL-2 and marked suppression when stimulated by TPA.  相似文献   
50.
Platelet activation altered the binding of three monoclonal antibodies (monovalent Fab' fragment) directed against the glycoprotein (GP) IIb/IIIa complex. An increased binding of two- to threefold occurred after stimulation with thrombin or phorbol myristate acetate (PMA), with slight but significant increase in the dissociation constants (Kd) of two antibodies (LJ-CP8 and LJ-P9). In contrast, no statistically significant changes were observed with ADP-stimulated platelets. The increased binding of LJ-CP3, but not of the other two antibodies, to activated platelets decreased by 30% to 40% in the presence of EDTA at 22 to 25 degrees C. Platelets stimulated by thrombin or PMA bound more fibrinogen than did those stimulated by ADP, and significant differences in the extent but not in the affinity of fibrinogen binding were observed with various platelet agonists. When the pool of GP IIb/IIIa molecules exposed on the surface of unstimulated platelets was reacted with the monoclonal antibody LJ-CP3 to block ADP-induced fibrinogen binding and platelet aggregation, stimulation with thrombin or PMA still induced substantial binding of antibody and fibrinogen, and aggregation ensued. Therefore, platelets exposed to "strong" agonists exhibit an increased number of surface-oriented epitopes associated with GP IIb/IIIa. The GP IIb/IIIa molecules bearing these newly exposed epitopes are functional in that they can bind fibrinogen and mediate platelet aggregation.  相似文献   
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