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11.
All sturgeon VL segments isolated in this study belong to a single family, VLI, which can be divided into two subfamilies. Of the 79 cDNA clones isolated, 76 belong to the larger subfamily, VLIa, and only 3 clones constitute the smaller subfamily, VLIb. To evaluate variability, the Shannon entropy was estimated for each individual amino acid position, and to facilitate comparisons of variability between species the mean entropy of the CDR regions was calculated. In such a comparison, the sturgeon was found to have CDR1 and CDR3 variability approaching those found in mouse and clawed frog, but showed very low variability for CDR2. Amino acid position 50 does however display variability in the range of mouse and clawed frog. It is further confirmed that the sturgeon has numerous J segments, but that the junctional diversity does not contribute greatly to the diversity of the light chain. Comparisons of cDNA clones and a genomic VL segment indicate that the VL undergoes changes, particularly in the CDR regions, in a manner that can be explained by somatic hypermutation and/or gene conversion.  相似文献   
12.
A remediable cause of poor treatment response in drug‐susceptible tuberculosis (TB) patients may be low plasma levels of one or more of the first‐line anti‐TB drugs. The aim of this work was to develop an accurate and precise LC‐MS/MS method for simultaneous quantification of all four first‐line anti‐TB drugs in plasma suitable for therapeutic drug monitoring (TDM). To adjust for degradation and losses during sample preparation, isotopically labeled compounds were used as internal standards. Plasma samples spiked with internal standards were extracted using protein precipitation with methanol and acetonitrile. Simultaneous separation of all four drugs was accomplished with a Chromolith Reversed‐Phase column and mobile phases consisting of water, methanol, ammonium acetate and formic acid with subsequent mass spectrometric quantification. The linear range of the calibration curve for isoniazid was 0.5–10 mg/L, for rifampicin 0.75–30 mg/L, for ethambutol 0.25–10 mg/L and for pyrazinamide 4–80 mg/L. The lower limit of quantification was 0.5 mg/L, 0.75 mg/L, 0.25 mg/L and 4.0 mg/L, respectively. Precision estimated by the coefficient of variation was <15% for all four drugs. The LC‐MS/MS method can readily be used for simultaneous quantification of first‐line anti‐TB drugs in plasma and is well suited for TDM.  相似文献   
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A system to improve the management of emergencies during pregnancy, childbirth, infancy and childhood in a region of The Gambia (Brikama) with a population of approximately 250,000 has been developed. This was accomplished through formal partnership between the Gambian Ministry of Health, the World Health Organisation, Maternal Childhealth Advocacy International and the Advanced Life Support Group. Since October 2006, the hospital in Brikama has been renovated and equipped and more efficiently provided with emergency medicines. An emergency ambulance service now links the community with the hospital through a mobile telephone system. Health professionals from community to hospital have been trained in obstetric, neonatal and paediatric emergency management using skills' based education. The programme was evaluated in log books detailing individual resuscitations and by external assessment. The hospital now has constant water and electricity, a functioning operating theatre and emergency room; the maternity unit and children's wards have better emergency equipment and there is a more reliable supply of oxygen and emergency drugs, including misoprostol (for treating post partum haemorrhage) and magnesium sulphate (for severe pre-eclampsia). There is also a blood transfusion service. Countrywide, 217 doctors, nurses, and midwives have undergone accredited training in the provision of emergency maternal, newborn and child care, including for major trauma. 33 have received additional education through Generic Instructor Courses and 15 have reached full instructor status. 83 Traditional Birth Attendants and 48 Village Health Workers have been trained in the recognition and initial management of emergencies, including resuscitation of the newborn. Eleven and ten nurses underwent training in peri-operative nursing and anaesthetics respectively, to address the acute shortage required for emergency Caesarean section. Between May 2007 and March 2010, 109 patients, mostly pregnant mothers, were stabilised and transported to hospital by the new emergency ambulance service. 293 resuscitation attempts were documented in personal logbooks. A sustainable system for better managing emergencies has been established and is helping to negate the main obstacle impeding progress: the country's lack of available trained medical and nursing staff. However, insufficient attention was paid to improving staff morale and accommodation representing significant failings of the programme.  相似文献   
16.
An intravenous glucose tolerance test was performed in 45 untreated patients with active inflammatory rheumatoid arthritis and in age- and sex-matched healthy subjects. The mean k value in the patients, which correlated to the inflammatory activity, was 1.0 +/- 0.05 (SEM), which was significantly lower (P less than .001) than in the controls (1.8 +/- 0.09). The basal serum insulin concentration and the maximum insulin response to glucose loading were significantly higher (P less than .001 and P less than .01, respectively) in the patient group. The patients had a normal basal concentration of growth hormone in the serum, but during glucose infusion the concentration increased. The plasma glucagon level was significantly lower than in the controls (P less than .001). The urinary output of cortisol and catecholamines was normal. It is concluded that impaired glucose handling in active chronic inflammatory disease cannot be explained as a stress reaction but may be due to peripheral insulin resistance mediated by the inflammatory process. A paradoxical increase in growth hormone secretion during glucose infusion may suggest that this hormone is one factor that influences glucose handling in chronic inflammation. The pathophysiologic relevance of altered glucose metabolism and enhanced insulin secretion is uncertain but may reflect a possible link with the proposedly increased risk of atherosclerotic cardiovascular disease in rheumatoid arthritis.  相似文献   
17.
Ten patients with malignant endocrine pancreatic tumors were treated with SMS 201-995 at doses of 50 micrograms twice daily, administered subcutaneously. Four out of 10 patients (40%)-1 patient with the Zollinger-Ellison syndrome and 3 of 6 with the watery diarrhea syndrome--responded objectively with more than 50% reduction of peptide levels, with a median duration of 15.5 months. All four patients improved symptomatically, with decreasing dyspeptic symptoms and decreasing diarrhoea. Three additional patients had a clear relief of symptoms without an effect on tumor-secreted peptides. The disease progressed in three patients during treatment. No reduction of tumor mass was seen in any of the patients. The main side effect noted was a slight but maintained increase in fasting blood glucose in four patients. In conclusion, SMS 201-995 had a beneficial effect in more than half of the patients and seems to be a valuable adjunct to other causal therapy in this patient category, especially in acute situations and weak patients because of its very few side effects.  相似文献   
18.
Vasoactive intestinal peptide (VIP) and the newly discovered pancreatic polypeptide (PP), both having been proposed as pathogenetic factors in the watery diarrhea syndrome (WDRA), were intravenously infused into rats in order to study the effect on small bowel propulsion. Simultaneously with the infusion of hormone, radioactive test substance was continuously infused into the duodenum of the conscious animal through a permanent catheter. By recording the distribution of radioactivity along the excised gastrointestinal tract, analyses of small bowel propulsion were possible. After infusion of VIP small bowel transit time was significantly prolonged, and the local propagation velocity was retarded both in the proximal and the distal part of the small bowel. PP did not alter small bowel populations. The heavily retarded transport rate after VIP is a propulsive dysfunction and not inconsistent with the clinical sign of diarrhea.  相似文献   
19.
Peroxisome proliferator‐activated receptor alpha (PPARα) is a molecular target for perfluoroalkyl substances (PFASs). Little is known about the cellular uptake of PFASs and how it affects the PPARα activity. We investigated the relationship between PPARα activity and cellular concentration in HepG2 cells of 14 PFASs, including perfluoroalkyl carboxylates (PFCAs), perfluoroalkyl sulfonates and perfluorooctane sulfonamide (FOSA). Cellular concentrations were determined by high‐performance liquid chromatography–tandem mass spectrometry and PPARα activity was determined in transiently transfected cells by reporter gene assay. Cellular uptake of the PFASs was low (0.04–4.1%) with absolute cellular concentrations in the range 4–2500 ng mg?1 protein. Cellular concentration of PFCAs increased with perfluorocarbon chain length up to perfluorododecanoate. PPARα activity of PFCAs increased with chain length up to perfluorooctanoate. The maximum induction of PPARα activity was similar for short‐chain (perfluorobutanoate and perfluoropentanoate) and long‐chain PFCAs (perfluorododecanoate and perfluorotetradecanoate) (approximately twofold). However, PPARα activities were induced at lower cellular concentrations for the short‐chain homologs compared to the long‐chain homologs. Perfluorohexanoate, perfluoroheptanoate, perfluorooctanoate, perfluorononanoate (PFNA) and perfluorodecanoate induced PPARα activities >2.5‐fold compared to controls. The concentration–response relationships were positive for all the tested compounds, except perfluorooctane sulfonate PFOS and FOSA, and were compound‐specific, as demonstrated by differences in the estimated slopes. The relationships were steeper for PFCAs with chain lengths up to and including PFNA than for the other studied PFASs. To our knowledge, this is the first report establishing relationships between PPARα activity and cellular concentration of a broad range of PFASs.  相似文献   
20.
Objectives: To perform an ergonomic analysis of work and machinery-related risks in a group of Swedish older farmers, investigating farmers’ attitudes and perceptions about: 1) health status and work motivation, 2) physical and cognitive workload and difficulties in the interaction with machinery and technological innovations, and 3) risks and safety practices. Methods: Nine Swedish male farmers aged 65+ were administered a semi-structured interview and a questionnaire. Results: Participants perceived themselves as being in good health and considered farming as a good proxy of their health status. They reported an increased physical workload but did not describe any cognitive workload. Technology was reported to have low usability, and thus its benefits cannot be fully exploited. Older farmers acknowledged the existence of “new risks” related to the aging process and mainly referred to the common sense and previous experience as the best safety practices. Conclusion: Multilevel interventions focused on the capabilities and limits of the older farmers should be developed, involving both training activities and design solutions for the machinery that can support older farmers’ health and safety.  相似文献   
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