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Groin complications remain the most common complication of cardiac catheterization procedures. While the use of closure devices is increasing for arterial sheaths, venous sheaths tend to be removed and hemostasis achieved with manual compression. We report our experience using Perclose suture-mediated vascular closure device to achieve hemostasis and early mobility in patients who have had venous access as part of their procedure. There were a total of 42 patients (21 males; average age, 63.5 years) studied. The majority of the patients had 7 Fr sheaths (24), with access sites of sheaths up to 14 Fr being closed with this technique. Two patients developed complications at the access site: one patient requiring rehospitalization for intravenous antibiotics because of late access site infection, and one patient with deep venous thrombosis and pulmonary emboli. We conclude that the use of the Perclose suture-mediated closure device for closure of femoral venous access sites is feasible and should be considered especially in patients with larger venous sheaths and those at increased risk of groin complications.  相似文献   
3.
Small, patent cerebral aneurysms: atypical appearances at 1.5-T MR imaging   总被引:1,自引:0,他引:1  
Rolen  PB; Sze  G 《Radiology》1998,208(1):129
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4.
Hemolytic uremic syndrome (HUS) is associated with intestinal infection by enterohemorrhagic Escherichia coli strains that produce Shiga toxins. Globotriaosylceramide (Gb3) is the functional receptor for Shiga toxin, and tumor necrosis factor alpha (TNF-alpha) upregulates Gb3 in both human macrovascular umbilical vein endothelial cells and human microvascular brain endothelial cells. TNF-alpha treatment enhanced Shiga toxin binding and sensitivity to toxin. This upregulation was specific for Gb3 species containing normal fatty acids (NFA). Central nervous system (CNS) pathology in HUS could involve cytokine-stimulated elevation of endothelial NFA-Gb3 levels. Differential expression of Gb3 species may be a critical determinant of Shiga toxin toxicity and of CNS involvement in HUS.  相似文献   
5.
Cryptdins: antimicrobial defensins of the murine small intestine.   总被引:16,自引:18,他引:16       下载免费PDF全文
Paneth cells are specialized small intestine epithelial cells that contain lysozyme, possess phagocytic properties, and secrete cytoplasmic granules into the intestinal crypt lumen after the entry of bacteria. Recent studies by Ouellette and associates (A. J. Ouellette, R. M. Greco, M. James, D. Frederick, J. Naftilan, and J. T. Fallon, J. Cell Biol. 108:1687-1695, 1989) indicated that murine Paneth cells produce prodefensin mRNA, but the properties of its peptide product were not reported. We purified two closely related defensins, cryptdin 1 and cryptdin 2, from a subcellular fraction of murine small intestine cells that was enriched in Paneth cells. Both peptides contained 35 amino acid residues, including the characteristic defensin "signature" of six invariantly conserved cysteines. Cryptdins 1 and 2 were approximately 90 to 95% homologous to each other and to the carboxy-terminal domain of the 93-amino-acid defensin precursor, cryptdin A, described by Ouellette and associates (Ouellette et al., J. Cell Biol. 108:1687-1695, 1989). Both cryptdins exerted bactericidal activity against Listeria monocytogenes EGD and Escherichia coli ML-35p in vitro. Their potency exceeded that of human neutrophil defensin HNP-1 but was considerably lower than that of NP-1, a defensin produced by rabbit neutrophils and alveolar macrophages. Both cryptdins killed mouse-avirulent Salmonella typhimurium 7953S (phoP) much more effectively than its phoP+, mouse-virulent, isogenic counterpart, S. typhimurium 14028S. Our data indicate that mouse intestinal prodefensins are processed into 35-amino-acid mature defensins (cryptdins) with broad-spectrum antimicrobial properties. The production of defensins and lysozyme by Paneth cells may enable them to protect the small intestine from bacterial overgrowth by autochthonous flora and from invasion by potential pathogens that cause infection via the peroral route, such as L. monocytogenes and Salmonella species.  相似文献   
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Didemnin B (NSC-325319), a new depsipeptide isolated from a Caribbean tunicate, has been evaluated in a clinical phase I study. The drug was administered in a schedule of a 4 weekly intravenous injection in a six-weeks cycle. Fifty-three patients received 71 evaluable cycles in an escalated dose ranging from 0.4 mg/m2/week to 2.5 mg/m2/week. No hematological toxicity was demonstrated at any dose level. Without prophylactic antiemetics nausea and vomiting was dose limiting at 1.2 mg/m2/week. Due to the use of Cremophor EL as a solvent, hypersensitivity reactions occurred in 9 patients. These reactions occurred following prior exposure to the drug and were commonly seen at the 3rd dose. They were not dose related but became more frequent at 1.5 mg/m2/week necessitating prophylactic treatment with H1 and H2 receptor blocking agents. Non-hematological toxicities included mild diarrhea, mucositis, anorexia, headaches, and local phlebitis. The dose- limiting toxicity was generalized weakness which became severe and disabling in 3 of 6 patients treated at 2.5 mg/m2/week. No objective responses were documented in 39 patients with evaluable disease. The recommended dose for phase II studies was 2.3 mg/m2/week × 4 4 in a 6-weeks cycle given with prophylactic antiemetics and H1 and H2 receptor blocking agents.  相似文献   
8.
This study was designed to compare the growth of Pakistani schoolchildren in the UK with the 1990 UK growth standards. Measurements of height, weight, and sitting height were performed on 785 Pakistani schoolchildren aged 5-14 years with the mean values for each age and sex being plotted on the UK growth standards. The results were expressed as SD scores relative to the 1990 reference data. The mean height for the boys was only 0.2 SD scores below the mean for the new growth standards with the mean height for the girls being 0.4 SD scores below the mean. The mean values for weight and body mass index were 0.3 and 0.5 SD scores less than the mean for boys and girls respectively. This study demonstrates that the growth of Pakistani schoolchildren in the UK is comparable to the 1990 UK growth standards with only minor differences. It is not safe to assume that short stature or low body weight in a Pakistani child is due to his or her ethnic background.  相似文献   
9.
PURPOSE: Liposomal lurtotecan (OSI-211) is a liposomal formulation of the water-soluble topoisomerase I inhibitor lurtotecan (GI147211), which demonstrated superior levels of activity compared with topotecan in preclinical models. We studied two schedules of OSI-211 in a randomized design in relapsed ovarian cancer to identify the more promising of the two schedules for further study. PATIENTS AND METHODS: Eligible patients had measurable epithelial ovarian, fallopian, or primary peritoneal cancer that was recurrent after one or two prior regimens of chemotherapy. Patients were randomly assigned to receive either arm A (OSI-211 1.8 mg/m(2)/d administered by 30-minute intravenous infusion on days 1, 2, and 3 every 3 weeks) or arm B (OSI-211 2.4 mg/m(2)/d administered by 30-minute intravenous infusion on days 1 and 8 every 3 weeks). The primary outcome measure was objective response, which was confirmed by independent radiologic review, and a pick the winner statistical design was used to identify the schedule most likely to be superior. RESULTS: Eighty-one patients were randomized between October 2000 and September 2001. The hematologic toxic effects were greater on arm A than on arm B (grade 4 neutropenia, 51% v 22%, respectively), as was febrile neutropenia (26% v 2.4%, respectively). Of the 80 eligible patients, eight patients (10%) had objective responses; six responders (15.4%; 95% CI, 6% to 30%) were in arm A and two responders (4.9%; 95% CI, 1% to 17%) were in arm B. CONCLUSION: The OSI-211 daily for 3 days intravenous schedule met the statistical criteria to be declared the winner in terms of objective response. This schedule was also associated with more myelosuppression than the schedule of OSI-211 administered in arm B.  相似文献   
10.
Purpose: MG98 is a second generation phosphorothioate antisense oligodeoxynucleotide which is a highly specific inhibitor of translation of the mRNA for human DNA MeTase I (DNMT 1). This phase I study examined the toxicity and pharmacologic profile of MG98 administered as a continuous 21-day intravenous infusion every 4 weeks. Patients and methods: Fourteen patients with solid cancers received a total of 25 cycles of MG98 at doses ranging from 40 to 240 mg/m2/day. Steady-state concentrations of MG98 were measured as were several pharmacodynamic assessments including mRNA of the target gene, DNMT1, in PBMC. In addition, other potential surrogate markers of drug effects were explored, including hemoglobin F, Vimentin and GADD45. Results: Dose limiting effects were drug-related reversible transaminase elevation and fatigue seen at doses of 240, 200 and 160 mg/m2/day. The dose level of 80 mg/m2/day was felt to be safe and tolerable when delivered on this schedule. No evidence of antitumor activity was observed. Although pharmacokinetic analysis revealed that at the higher dose levels, mean Css values of MG98 were approximately 10-fold times the IC50 values associated with target inhibition in vitro, the extent of MG98 penetration into target tumors in this trial was not determined. No consistent, dose-related changes in correlative markers including DNMT1 mRNA, hemoglobin F, Vimentin and GADD45, were observed. Conclusions: This schedule of MG98 given as a 21-day continuous intravenous infusion every 4 weeks was poorly tolerated in the highest doses; therefore, further disease-site specific evaluation of the efficacy of this agent will utilize a more favorable, intermittent dosing schedule. Pharmacodynamic evaluations undertaken in an attempt to explore and validate the biological mechanisms of MG98 did not show dose-related effects.  相似文献   
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