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To estimate the degree of coagulopathy in abdominal sepsis, we measured the plasma levels of prothrombin fragment 1 + 2 (F1 + 2), thrombin-antithrombin III complex (TAT) and plasmin-alpha 2-plasmin inhibitor complex (PIC) by the enzyme-linked immunosorbent assay in 38 patients with disseminated intravascular coagulation (DIC). In 20 patients with DIC due to abdominal sepsis, plasma levels of F1 + 2, TAT and PIC were 2.6 nmol/l, 27.9 micrograms/l and 1.5 micrograms/ml, respectively, with a mean antithrombin III (AT III) activity of 41.7%. F1 + 2, TAT, PIC and AT III levels were 4.7 nmol/l, 75.8 micrograms/l, 8.8 micrograms/ml and 70.9% in 18 patients with DIC as the result of malignancy. Though AT III levels in DIC due to sepsis were lower than those in DIC due to malignancy, the levels of F1 + 2, TAT and PIC in the former were not significantly more increased than those in the latter. The plasma levels of F1 + 2 were positively correlated with TAT and PIC in DIC patients with malignancy; however, there was no correlation between F1 + 2 and TAT or PIC in DIC patients with sepsis. In addition, the levels of serum albumin in the two groups were similar. These results suggest that activation of coagulation and fibrinolytic systems may not be so prominent in cases of DIC due to abdominal sepsis, compared to related events in DIC due to malignancy. It is also suggested that the depletion of AT III in cases of sepsis is not only caused by a consumption related to intravascular coagulation or to an alternate distribution of protein.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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L-Glutamate and related excitatory amino acids (EAA) are firmly established as major excitatory synaptic transmitter substances in the vertebrate central nervous system. Questions which have been addressed include: How many receptors are there for the EAAs?; What ion channels and/or 'second-messenger' systems are regulated by these receptors?; What are the roles of EAAs in higher neural functions?; Are they involved in neurological disorders? EAA receptors appear not only to mediate normal synaptic transmission along excitatory pathways but also to participate in the modification of synaptic connections during development. However, overaction of receptors can also mediate neuronal degeneration and even cell death. NMDA receptor antagonists markedly attenuate neuronal necrosis. Therefore, it appears that ischemia- and hypoglycemia-associated brain damage results not from a lack of energy substrates but rather via the mediation of NMDA receptors and 'excitotoxic' mechanisms. The action of ketamine anesthesia is closely associated with a block of the NMDA receptor. Ketamine binds to a site within the lumen of the NMDA-activated channel and can become trapped there when the channel closes. Current evidence indicated that NMDA receptor antagonists will be of value for the treatment of delayed neuronal death. NMDA receptor will lead to understanding the mechanisms underlying learning and memory, the control of neuronal excitability and neuronal death.  相似文献   
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Ruthenium red (3-5 microM) antagonism of the inhibitory effect of capsaicin (1 microM) on the contractile response to mesenteric nerve stimulation in the presence of hexamethonium (50 microM) and guanethidine (2 microM) was reversed significantly by sialic acid (2 mM) or neuraminidase (0.1 U/ml). These results suggested that ruthenium red at low concentrations inhibits the capsaicin-induced desensitization of activated Ca2+ influx into sensory nerves at least in part by binding to sialic acid residues.  相似文献   
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The effect of gamma-aminobutyric acid (GABA) on the human internal anal sphincter was investigated. Cumulative applications of GABA produced concentration-dependent contractions (10(-8)-10(-5) M) of the isolated human sphincter. Pretreatment with bicuculline (GABAA antagonist) turned them to relaxation. Muscimol, a GABAA agonist, induced concentration-dependent contractions (10(-8)-10(-5) M); however, baclofen (GABAB agonist, 10(-8)-10(-5) M) promoted concentration-dependent relaxation of the strips. These results suggested that both excitatory GABAA receptors and inhibitory GABAB receptors exist in the internal anal sphincter. Oral administration of sodium valproate (1600 mg/day), a GABA transaminase inhibitor, enhanced the anal canal resting pressure in 10 normal volunteers. Anal manometry showed a significant elevation in tonus without affecting amplitudes or frequencies. These results indicated that endogenous GABA, which was increased by sodium valproate, produced elevations in the anal canal resting pressure through its specific receptors in the human internal anal sphincter.  相似文献   
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Abstract: Recently, successful results of ulcerative colitis (UC) treatments with leukocyte apheresis have been reported by several institutes. To certify the efficacy of leukocyte apheresis in refractory UC patients, a multicenter open label trial was conducted, and results were analyzed. Fifty patients diagnosed with active steroid‐resistant UC were enrolled in this study from 14 medical centers. Using a centrifugal cell separator (Component Collection System, Haemonetics), leukocyte apheresis was performed once a week for 5 weeks. General conditions and abdominal symptoms were recorded daily, and laboratory tests were followed weekly. Changes of colonoscopic and histological manifestations of luminal activity through the study period were evaluated. At the end of the study period, stool frequency was decreased to less than 4 times a day in 68.4% (26 of 38) and serum C‐reactive protein (CRP) concentration was normalized in 56.7% (17 of 30) of the patients. Colonoscopic remission was achieved in 57.7% (26 of 45), and histological improvement was noted in 54.1% (20 of 37) of the patients tested. Improved disease activity was demonstrated in 74% (37 of 50) of the patients by general assessment criteria. Analysis of the trial data confirmed the valid clinical efficacy of leukocyte apheresis by centrifugal cell separator in refractory UC patients.  相似文献   
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A 52 year-old woman noticed general fatigue, polyarthralgia, and muscle weakness of lower extremities in October 2001. In December, she felt difficulty in walking due to muscle weakness. In January 2002, she admitted another hospital because of dyspnea on exertion and edema of lower extremities. Laboratory test revealed leukocytopenia, the elevation of creatine kinase and positive anti-U1-RNP antibodies. Her chest computed tomography (CT) showed severe interstitial pneumonia. Cardiac echogram revealed that she had pericardial effusion and pulmonary hypertension. Then she was transferred to Keio University Hospital and she was diagnosed as having mixed connective tissue disease (MCTD) manifestating myositis, interstitial pneumonia, pulmonary hypertension and pericarditis. Prednisolone (PSL) 60mg daily following to methylprednisolone (mPSL) pulse therapy was begun and her symptoms were gradually improved. In middle of February, she complained of high fever over 39.0 degrees C. Bacterial culture tests were negative and laboratory data indicated pancytopenia and a high level of serum ferritin. Bone marrow aspiration revealed hemophagocytosis in bone marrow specimens and she was diagnosed as having hemophagocytic syndrome associated with MCTD. mPSL pulse therapy was not effective and intermittent cyclophosphamide pulse therapy (IV-CY) was performed resulting in improvement of the symptoms. This case suggested the effectiveness of IV-CY therapy in patients with corticosteroid-resistant HPS associated with connective tissue diseases.  相似文献   
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Leiomyoblastoma has been regarded as a neoplasm of smooth muscle origin. With recent progress in immunohistostaining techniques, many clinicopathological discrepancies have been pointed out about the origin of leiomyoblastoma. It has been claimed that gastrointestinal non-epithelial tumors should be regarded as stromal tumors in order to study their origin. In the present study, we performed various forms of immunohistostaining in seven cases of leiomyoblastoma to determine their origin. One case expressed desmine and muscle specific actin and was considered to be derived from smooth muscle. Four neoplasms expressed X-100 protein (two cases were also NSE positive) and were thought to be derived from the nerve. Two cases were of unknown derivation. These results suggest that the cells of leiomyoblastoma may arise from a primitive to totipotential cell of neural lineages that may anomalously express smooth muscle filaments.  相似文献   
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