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A substantial proportion of patients with adult-onset diabetes share features of both type 1 diabetes (T1D) and type 2 diabetes (T2D). These individuals, at diagnosis, clinically resemble T2D patients by not requiring insulin treatment, yet they have immunogenetic markers associated with T1D. Such a slowly evolving form of autoimmune diabetes, described as latent autoimmune diabetes of adults (LADA), accounts for 2–12% of all patients with adult-onset diabetes, though they show considerable variability according to their demographics and mode of ascertainment. While therapeutic strategies aim for metabolic control and preservation of residual insulin secretory capacity, endotype heterogeneity within LADA implies a personalized approach to treatment. Faced with a paucity of large-scale clinical trials in LADA, an expert panel reviewed data and delineated one therapeutic approach. Building on the 2020 American Diabetes Association (ADA)/European Association for the Study of Diabetes (EASD) consensus for T2D and heterogeneity within autoimmune diabetes, we propose “deviations” for LADA from those guidelines. Within LADA, C-peptide values, proxy for β-cell function, drive therapeutic decisions. Three broad categories of random C-peptide levels were introduced by the panel: 1) C-peptide levels <0.3 nmol/L: a multiple-insulin regimen recommended as for T1D; 2) C-peptide values ≥0.3 and ≤0.7 nmol/L: defined by the panel as a “gray area” in which a modified ADA/EASD algorithm for T2D is recommended; consider insulin in combination with other therapies to modulate β-cell failure and limit diabetic complications; 3) C-peptide values >0.7 nmol/L: suggests a modified ADA/EASD algorithm as for T2D but allowing for the potentially progressive nature of LADA by monitoring C-peptide to adjust treatment. The panel concluded by advising general screening for LADA in newly diagnosed non–insulin-requiring diabetes and, importantly, that large randomized clinical trials are warranted.  相似文献   
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To estimate the impact of office equipment on the quality of indoor air, the emission of ozone and organic volatiles was measured from one photocopier and four laser printers, three of which operated according to traditional corona discharge technology. The laser printers equipped with traditional technology emitted significant amounts of ozone and formaldehyde. Lesser amounts of other volatile aldehydes were emitted during printing. The photocopier emitted mainly ozone. In a well-ventilated office environment, the amounts encountered here for individual volatiles were within recommended maximum exposure limits for a reasonable density of printers. Because it is not known whether the concentration of irritating volatiles, such as formaldehyde, should be kept lower in an ozone rich environment or not, and because emissions in the immediate vicinity of the printers exceeded recommendations, the authors recommend that laser printers equipped with the traditional corona rods not be placed beside or immediately at the working site of office personnel. This way, ozone concentrations can be kept below recommended maximum exposure limits, provided that the ventilation rate is adequate. Further, it seems that if a reliable quantitative comparison of total organic volatiles prior to and during printing is to be made, the inertness of the sorbent toward ozone should be confirmed.  相似文献   
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We conducted a feasibility study of teleconsultation in dermatology using low-cost equipment. Patients and their general practitioners took part in consultations from the Primary Health Care Centre in Ikaalinen with a dermatologist 55 km away at the Tampere University Hospital (TAUH). Consultations were performed using standard commercial videoconferencing equipment, a modified document camera and a dermatoscope. A single ISDN line (128 kbit/s) was used for the connection. During the eight months of the study, 25 patients participated in a teledermatology consultation. Their mean age was 45 years (range 4-92). The average time the patient spent in travelling to the videoconsultation (i.e. one way) was 24 min (range 5-65 min). The mean time spent in the teleconsultation was 15 min (range 5-30 min). After the teleconsultation, patients' treatments changed in 19 cases (76%), diagnoses were changed in 13 cases (52%) and 18 patients (72%) did not need to go to the TAUH. The equipment was generally reliable and easy to use. However, the dermatoscope was not very useful and only one of the consultations relied mainly on it. The cost of the teleconsultations for the 18 patients who avoided travel to the TAUH was FM18,627. The total costs for the 18 conventional consultations in the TAUH would have been FM18,034. The main economic benefits of the videoconferencing were attributable to the reduced travelling and hospital costs. The economic benefits of medical education were more difficult to quantify.  相似文献   
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This study is the first report of saxitoxin in cyanobacterial blooms in Finland. Bloom samples (n = 50) were collected from Finnish freshwater sites during summer months of 2002 and 2003. These samples were screened for the presence of paralytic shellfish toxins (PSTs) using the Jellett rapid PSP screening test. Samples testing positive for PSTs (n = 7) were further analyzed with saxiphilin- and voltage-gated sodium channel [(3)H]-STX-binding radioreceptor assays and liquid chromatography using fluorescence and mass spectrometric analysis. The results indicated that saxitoxin (STX) was the only PST analogue in the samples and that it was present in high concentrations, as much as 1 mg L(-1). Microscopic analysis revealed that 95%-100% of the phytoplankton in the positive samples consisted of Anabaena lemmermannii. The trophic status of lakes in which STX-containing blooms were found varied from oligotrophic to hypertrophic. All the lakes had high nitrogen-to-phosphorus ratios. In some instances, samples had been collected from sites where swimmers had reported adverse health effects, and in three such cases, reported adverse health effects were associated with sites from which samples testing positive for STX had been received. Symptoms of fever, eye irritation, abdominal pains, and skin rash were reported in children aged 2-10 years after exposure to the water. These were not the adverse human symptoms typical of STX poisoning; rather, they represented acute effects often reported following recreational exposure to cyanobacterial blooms.  相似文献   
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A case of acute permanent anosmia is described in a renovation worker during exposure to a waterproof coating chemical. The chemical consisted of several substances of which four (acetone, acrylates, butyl acetate and carbon disulfide) has been previously reported to induce hyposmia or anosmia in workers. Other aetiologies were clinically excluded but a large arachnoidea cyst in the frontal part of the left temporobasal fossa with possible compression of the left entorhinal cortex. The toxic aetiology of anosmia is supported by the acute onset and the temporal relationship with occupational exposure. The silent cyst as the cause of anosmia is improbable, but it may have had some contributory role. Our case illustrates both the challenges when clinically examining patients with work-related olfactory impairment and the importance of multi-disciplinary approach to such patients.  相似文献   
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The genes for the sulfonylurea receptor (SUR1; encoded by ABCC8) and its associated islet ATP-sensitive potassium channel (Kir6.2; encoded by KCNJ11) are adjacent to one another on human chromosome 11. Multiple studies have reported association of the E23K variant of Kir6.2 with risk of type 2 diabetes. Whether and how E23K itself-or other variant(s) in either of these two closely linked genes-influences type 2 diabetes remains to be fully determined. To better understand genotype-phenotype correlation at this important candidate gene locus, we 1) characterized haplotype structures across the gene region by typing 77 working, high-frequency markers spanning 207 kb and both genes; 2) performed association studies of E23K and nearby markers in >3,400 patients (type 2 diabetes and control) not previously reported in the literature; and 3) analyzed the resulting data for measures of insulin secretion. These data independently replicate the association of E23K with type 2 diabetes with an odds ratio (OR) in the new data of 1.17 (P = 0.003) as compared with an OR of 1.14 provided by meta-analysis of previously published, nonoverlapping data (P = 0.0002). We find that the E23K variant in Kir6.2 demonstrates very strong allelic association with a coding variant (A1369S) in the neighboring SUR1 gene (r(2) > 0.9) across a range of population samples, making it difficult to distinguish which gene and polymorphism in this region are most likely responsible for the reported association. We show that E23K is also associated with decreased insulin secretion in glucose-tolerant control subjects, supporting a mechanism whereby beta-cell dysfunction contributes to the common form of type 2 diabetes. Like peroxisome proliferator-activated receptor gamma, the SUR1/Kir6.2 gene region both contributes to the inherited risk of type 2 diabetes and encodes proteins that are targets for hypoglycemic medications, providing an intriguing link between the underlying mechanism of disease and validated targets for pharmacological treatment.  相似文献   
19.
Maturity-onset diabetes of the young (MODY) is a heterogeneous single gene disorder characterized by non-insulin-dependent diabetes, an early onset and autosomal dominant inheritance. Mutations in six genes have been shown to cause MODY. Approximately 15-20% of families fitting MODY criteria do not have mutations in any of the known genes. These families provide a rich resource for the identification of new MODY genes. This will potentially enable further dissection of clinical heterogeneity and bring new insights into mechanisms of beta-cell dysfunction. To facilitate the identification of novel MODY loci, we combined the results from three genome-wide scans on a total of 23 families fitting MODY criteria. We used both a strict parametric model of inheritance with heterogeneity and a model-free analysis. We did not identify any single novel locus but provided putative evidence for linkage to chromosomes 6 (nonparametric linkage [NPL]score 2.12 at 71 cM) and 10 (NPL score 1.88 at 169-175 cM), and to chromosomes 3 (heterogeneity LOD [HLOD] score 1.27 at 124 cM) and 5 (HLOD score 1.22 at 175 cM) in 14 more strictly defined families. Our results provide evidence for further heterogeneity in MODY.  相似文献   
20.
PURPOSE: Tenecteplase (TNK; TNKase) is a third-generation plasminogen activator approved for acute myocardial infarction with an enhanced safety profile compared to alteplase. The stability and bioactivity of reconstituted frozen/thawed and diluted tenecteplase solutions used in noncoronary peripheral thrombolysis was determined. MATERIALS AND METHODS: Lyophilized TNK was freshly reconstituted in sterile water (5 mg/mL) and used as control. In freeze/thaw studies, reconstituted TNK aliquots were stored frozen for 4 weeks at -20 degrees C, thawed at ambient temperature, and assayed with and without an additional freeze/thaw cycle. Additional freshly reconstituted TNK aliquots were assayed after six freeze/thaw cycles when frozen at two separate temperatures (-20 degrees and -70 degrees C) and thawed at 2-8 degrees C or ambient temperature. In dilution studies, reconstituted TNK was diluted in 500-mL commercially available normal saline solution bags to concentrations of 0.01, 0.02, and 0.05 mg/mL. Samples were assayed after 0, 8, and 24 hours at ambient temperature. Optical clarity, pH, protein concentration, particle counts, and in-vitro clot-lysis assays were performed. Protein monomer (%), single-chain protein (%), and particle counts were performed in freeze/thaw studies. RESULTS: Frozen/thawed TNK aliquots met all specifications as freshly reconstituted product. For dilution studies (0.01, 0.02, and 0.05 mg/mL), the recovered protein retained 83%-100% bioactivity after 24 hours. The recovered protein rates over the course of 24 hours (relative to target concentration) were 70%-75%, 80%-85%, and 94%-95% at 0.01, 0.02, and 0.05 mg/mL, respectively. Assayed solutions were clear/colorless at all concentrations and time points. CONCLUSION: TNK is fully active after reconstitution and freezing/thawing. TNK dilutions used in clinical practice (0.01-0.05 mg/mL) demonstrated retention of biologic activity at 24 hours without precipitates.  相似文献   
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