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81.
82.
BACKGROUND: This study was performed to determine the incidence of central venous device-related blood stream infection and thrombosis in patients treated with moderate dose continuous-infusion interleukin-2 (IL-2). METHODS: The records of 160 consecutive patients treated at the University of Wisconsin Hospital and Clinics, between June 1990 and June 1997, with moderate dose continuous-infusion IL-2 (IL-2 [1.5-3.0 x 10(6) U/m(2)/day] Hoffman-LaRoche, Nutley, NJ or IL-2 [4.5 x 10(6) U/m(2)/day] Chiron Corporation, Berkley, CA) were reviewed retrospectively. The majority of patients had metastatic melanoma (78 patients) or renal cell carcinoma (70 patients). All of the patients had a surgically implanted central venous device placed before starting IL-2 therapy; 89% of these were cuffed Hickman catheters. Eighty-four patients received 1 mg of warfarin per day as prophylaxis against device-related thrombosis; none received periinsertion prophylactic antibiotics. RESULTS: Twenty-one patients (13%) developed central venous device-related bloodstream infection (DRBSI) during the study period, a rate of 2 DRBSI per 1000 device-days. DRBSIs were associated with the type of immunotherapy given with IL-2 (P = 0.01) and with thrombosis (odds ratio, 4.1; 95% confidence interval, 1.5-11.4; P = 0.008) but not with patient gender, type of cancer, duration of the central device, or site of device placement. Twenty-six patients (16%) developed central venous device-related thrombosis (DRT) during immunotherapy. Low dose warfarin did not appear to prevent thrombosis. Device-related thrombosis was associated with DRBSI but not with patient gender, type of cancer, type of device, duration or location of device, or concomitant immunotherapy. CONCLUSIONS: Central venous DRBSI and DRT are significant complications that can occur during moderate dose continuous-infusion IL-2 therapy. The risk of DRBSI appears lower than the risk reported with high dose IL-2 therapy by previous investigators. The risk of DRT appears to be higher than the risk reported for patients with similar devices but not given IL-2. Low dose warfarin did not prevent DRT when started after device placement.  相似文献   
83.
The GlucoWatch (Cygnus, Inc, Redwood City, CA, USA) biographer provides automatic, frequent and noninvasive blood glucose measurements for up to 12 h. The device extracts glucose through intact skin where it is measured by an amperometric biosensor. Clinical trials in a variety of environments have shown that the biographer provides accurate and precise glucose measurements when compared with serial fingerstick blood glucose measurements. Mean difference between these measurements was 0.26 mmol/L in the home environment (r = 0.80). Over 94% of biographer readings were in the clinically acceptable A+B region of the Clarke Error Grid. A slight positive bias is observed for the biographer readings at low glucose levels. Biographer precision, as measured by coefficient of variation (CV)%, is approximately 10%. The low glucose alert function of the biographer was able to detect up to 75% of hypoglycaemic episodes with a low false alert level. Skin irritation, characterized by erythema and oedema was either nonexistent or mild in over 87% of subjects and resolved in virtually all subjects without treatment in several days. The GlucoWatch biographer has been shown to be a safe and effective method to track glucose level trends and patterns, which should enable improved glycaemic control for many patients.  相似文献   
84.
Summary: Mean 24-hour integrated concentrations of serum prolactin (PRL) in 8 breast-feeding mothers (62 ± 10.4 μg/1) was significantly higher than in 4 control subjects (14.8 ± 3.3 μg/1). No correlation was found between the mean integrated concentrations and time after delivery or breast-feeding status. There was no relationship between the mean integrated concentration of PRL or the basal PRL and the frequency of feedings, the total suckling time, the mean interval between feedings or the longest interval between feedings in the 24-hour period. The study provides conclusive evidence for increased prolactin secretion in long-term puerperal lactation.  相似文献   
85.
Enhanced gene transduction to the lung using cationic lipids could be attained through optimization of the structure of the lipids and the formulation of the cationic lipid:plasmid DNA (pDNA) complexes. We have expanded on our earlier observation of the importance of the structural orientation of the cationic lipid headgroup. Through the synthesis of a number of matched pairs of cationic lipids differing only in the configuration of their headgroup, we confirmed that those harboring a T-shape headgroup are more active than their linear counterparts, at least when tested in the lungs of BALB/c mice. Additionally, we demonstrated that not only are the structural considerations of these cationic lipids important, but also their protonation state, the free base being invariably more active than its salt counterpart. The salt forms of cationic lipids bound pDNA with greater avidity, which may have affected their subsequent intracellular dissolution and transit of the pDNA to the nucleus. Inclusion of a number of frequently used solutes in the vehicle severely inhibited the gene transfection activity of the cationic lipids. The selection of neutral co-lipids was also an important factor for overall transfection activity of the formulation, with significant gains in transfection activity realized when diphytanoylphosphatidylethanolamine or dilinoleoylphosphatidylethanolamine were used in lieu of dioleoylphosphatidylethanolamine. Finally, we showed that a transacylation reaction could occur between the cationic lipid and neutral co-lipid which reduced the transfection activity of the complexes. It is the hope that as our understanding of the many factors that influence the activity of these cationic lipid:pDNA complexes improves, formulations with much greater potency can be realized for use in the treatment of pulmonary diseases.  相似文献   
86.
The "at birth" system which is used in Sheffield to identify children likely to die unexpectedly in infancy, was tested retrospectively in Birmingham (83 cases) and in Newcastle upon Tyne (56 cases). The discrimination between cases and age-matched controls was poor in both cities. Analysis of the 8 factors used in the system showed that only 2 maintained significant case/control differences in Birmingham and Newcastle. Further investigation showed that other factors from maternity records showed significant case/control differences in these cities. Although the system used in Sheffield would not be of use in a prospective prevention programme in either Newcastle or Birmingham, the possibility of evolving an "at risk" system which might apply more widely is discussed.  相似文献   
87.
三尖杉树皮粗提取物中的一个新生物碱—高三尖杉酯碱酰胺(homoharringtonamide)的结构,经质谱—质谱分析,初步建议为16。类似的酰胺类生物碱,例如三尖杉碱酰胺(cephalotaxamide,6)、11-羟基三尖杉碱酰胺(11-hydroxycephalotaxamide,9)、三尖杉酯碱酰胺(harfingtonamide,14)或异三尖杉酯碱酰胺(isoharringtonamide,15)也可能存在,后三者(9,14,15)尚未见报道。  相似文献   
88.
Aim: To describe gut colonization in preterm infants using standard culture and 16S gene rRNA profiling, exploring differences in healthy infants and those who developed NEC/late onset sepsis (LOS). Methods: Ninety‐nine stools from 38 infants of median 27‐week gestation were cultured; 44 stools from 27 infants had their microbial profiles determined by 16S. Ordination analyses explored effects of patient variables on gut communities. Results: Standard microbiological culture identified a mean of two organisms (range 0–7), DGGE 12 (range 3–18) per patient. Enterococcus faecalis and coagulase negative staphylococci (CONS) were most common by culture (40% and 39% of specimens). Meconium was not sterile. No fungi were cultured. Bacterial community structures in infants with NEC and LOS differed from healthy infants. Infants who developed NEC carried more CONS (45% vs 30%) and less Enterococcus faecalis (31% vs 57%). 16S identified Enterobacter and Staphylococcus presence associated with NEC/LOS, respectively. Conclusions: Important differences were found in the gut microbiota of preterm infants who develop NEC/LOS. The relationship of these changes to current practices in neonatal intensive care requires further exploration.  相似文献   
89.
90.
The beta2 integrin (CD 18/CD 11 a, b, c) family of proteins mediate adherence of leukocytes to vascular endothelium and the associated ligand, intercellular adhesion molecule-1 (ICAM-1; CD 54), interacts with beta2 integrin proteins to allow transendothelial migration of leukocytes into sites of inflammation. The present study examines the function of these proteins in a murine model of acute cutaneous inflammation induced following topical application of 12-O- tetradecanoylphorbol-13-acetate (TPA) to the dorsal epidermis of SENCAR mice and in a model of skin multistage carcinogenesis. At 24 h following topical application of TPA to the dorsal epidermis of mice, dermal leukocytes expressed higher levels of beta2 integrin protein compared with the lower levels of beta2 integrin protein expression by peripheral blood leukocytes. ICAM-1 protein was localized to epidermal keratinocytes and vascular endothelium in TPA-treated skin and to proliferating papilloma cells. Intravenous (i.v.) injection of either 50 microg anti-beta2 integrin antibody alone or in combination with anti-ICAM-1 antibody significantly inhibited both TPA-stimulated neutrophil infiltration into the dermis (P < 0.001) and myeloperoxidase (MPO) activity (P < 0.03 anti-beta2 integrin antibody; P < 0.01 anti- beta2 integrin + ICAM-1 adhesion molecule antibodies), but had no effect on TPA-induced epidermal hyperplasia. In addition, injection of either anti-ICAM-1 adhesion molecule antibody alone (P < 0.004) or in combination with anti-beta2 integrin antibody (P < 0.001) significantly inhibited TPA-induced production of 7,8-dihydroxy-2'-deoxyguanosine (8- OHdG) immunoreactive proteins by epidermal keratinocytes. Beta2 integrin/ICAM-1 adhesion molecules work in concert to regulate migration, retention and functional activation of leukocytes within the dermis during TPA-induced skin inflammation and within stromal tissue of papillomas that form during multi-stage carcinogenesis. Agents that inhibit these receptor/ligand interactions may be useful in defining the roles of specific cell populations in cutaneous inflammation and multistage carcinogenesis and may also have potential as anti-promoting and anti-progression agents.   相似文献   
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