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71.
72.
This study was carried out on 57 normal infants: 22 full-term newborns, examined in the hospital laboratory, and 35 2–18-wk-old infants, examined in two resident nurseries. Polygraphic records, including 1–3 complete sleep cycles, were performed during the morning. The tracings were analyzed by 20-sec epochs.Three to 10% of active sleep states (AS) and 0.8-4% of quiet sleep states (QS) included ?3 sec respiratory pauses. There were minimal, non-significant differences between respiratory frequencies (RF) in total and in no-pause tracings.Our results confirmed that RF was higher in AS in all ages, when compared with QS (P < 0.02). During the transition (TS) from one to another well-defined sleep state, the respiratory rate showed an intermediate level (AS > TS > QS): the transition from AS to QS showed progressive slowing of RF, while the transition from QS to AS occurred abruptly, with sudden acceleration of RF. There was a significant slowing of RF during the course of QS, while the RF in AS was more variable without significant differences between the beginning, the middle and the end of AS state. In this material, RF was higher in 2–5-wk and 6–10-wk age groups, compared to newborns and to 11-18-wk-old infants. At all ages, there was a high degree of correlation (P < 0.01) between RF found in different sleep states for given individuals: some infants breathed more rapidly and others more slowly in all sleep states.A review of the literature showed that the differences between normal RF  相似文献   
73.
A new actinomycete strain, designated US80 and producing antimicrobial activities against Gram-positive and Gram-negative bacteria and fungi, was isolated from Tunisian oasis soil. Cultural characteristic studies strongly suggested that this strain belongs to the genus Streptomyces. The nucleotide sequence of the 16S rRNA gene (1517 pb) of Streptomyces sp. strain US80 exhibited close similarity (97-98%) with other Streptomyces 16S rRNA genes. Similarity of 98% was obtained with the 16S rRNA gene of Streptomyces roseoflavus, which produces the aminoglycoside antibiotic flavomycin. Study of the influence of different nutritional compounds on production of bioactive molecules showed that the highest antimicrobial activities were obtained when glucose at 1% (w/v) was used as sole carbon source in the presence of magnesium. Extraction of fermentation broth of Streptomyces sp. strain US80 and various separation and purification steps led to isolation of three pure active molecules. The chemical structure of these three compounds, named irumamycin (1a), X-14952B (1b) and 17-hydroxy-venturicidin A (1c), was established on the basis on their IR, ESI-MS, 1H and 13C/APT NMR data and by comparison with reference data from the literature.  相似文献   
74.
Recombinant human nerve growth factor (rhNGF) is regarded as the most promising therapy for neurodegeneration of the central and peripheral nervous systems as well as for several other pathological conditions involving the immune system. However, rhNGF is not commercially available as a drug. In this work, we provide data about the production on a laboratory scale of large amounts of a rhNGF that was shown to possess in vivo biochemical, morphological, and pharmacological effects that are comparable with the murine NGF (mNGF), with no apparent side effects, such as allodynia. Our rhNGF was produced by using conventional recombinant DNA technologies combined with a biotechnological approach for high-density culture of mammalian cells, which yielded a production of approximately 21.5 +/- 2.9 mg/liter recombinant protein. The rhNGF-producing cells were thoroughly characterized, and the purified rhNGF was shown to possess a specific activity comparable with that of the 2.5S mNGF by means of biochemical, immunological, and morphological in vitro studies. This work describes the production on a laboratory scale of high levels of a rhNGF with in vitro and, more important, in vivo biological activity equivalent to the native murine protein.  相似文献   
75.
Two infants were studied born of a mother with autosomal dominant hypocalcemia who is heterozygous for an activating mutation in the calcium-sensing receptor gene. Both infants had serum calcium levels in the low-normal range and parathyroid hormone levels in the high-normal range and were healthy. The mother's hypocalcemia had been treated with calcium carbonate and calcitriol and she has nephrocalcinosis and mild renal insufficiency. By genetic testing, both infants were shown to have normal calcium-sensing receptor gene alleles, i.e., they had not inherited the activating mutation from their mother. This provided reassurance to the family and ensured that treatment to correct apparent hypocalcemia would not be necessary. The fact that the infants had high normal parathyroid hormone levels with normal calcium may be due to the fact that with a normal calcium-sensing receptor their parathyroid glands responded in utero to the maternal hypocalcemia with an increase in parathyroid hormone.  相似文献   
76.
Screening is a critical step in the discovery of microbial agents that can exert biological control of Fusarium verticillioides at the root level. The objectives of this research were to determine the utility of a niche overlap index to realise the first screening of maize rhizobacterial isolates during different water activities. Studies were conducted to evaluate various methods for second screening with different modes of action. The antifungal activity of bacterial isolates through antibiosis assay was checked and the influence of different isolates on Fusarium verticilliodes growth and fumonisin B(1) was studied. Eleven competitive rhizobacterial isolates (Arthrobacter globiformis RC1, Azotobacter armeniacus RC2, A. armeniacus RC3, A. globiformis RC4, A. globiformis RC5, A. armeniacus RC6, Pseudomonas solanacearum RC7, Bacillus subtilis RC8, B. subtilis RC9, P. solanacearum RC10, B. subtilis RC11) were selected for the studies which followed. All bacteria were able to utilise the widest range of carbon sources and showed the highest niche overlap indices at the water activities tested. All bacterial antagonists reduced fumonisin B(1) production at all levels tested. Isolates belonging to Pseudomonas and Bacillus genera significantly inhibited fumonisin B(1) production, which ranged between 70 and 100%. Also, A. armeniacus RC2 caused important fumonisin B(1) reduction. The results of the present work suggest that A. armeniacus RC2, A. armeniacus RC3, B. subtilis RC8, B. subtilis RC9, B. subtilis RC11, P. solanacearum RC7, and P. solanacearum RC10 could have practical value in the control of F. verticillioides root colonisation. This paper is part of an on-going study to determine their application at the field level.  相似文献   
77.
Human infection by leptospires has highly variable clinical manifestations, which range from subclinical infection to fulminant disease. We conducted a population-based, cross-sectional seroepidemiologic study in Peru to determine potential relationships of environmental context to human exposure to Leptospira and disease associated with seroconversion. Three areas were studied: a flooded, urban slum in the Peruvian Amazon city of Iquitos; rural, peri-Iquitos villages; and a desert shantytown near Lima. Seroprevalence in Belen was 28% (182/650); in rural areas, 17% (52/316); and in a desert shantytown, 0.7% (1/150). Leptospira-infected peridomestic rats were found in all locales. In Belen, 20 (12.4%) of 161 patients seroconverted between dry and wet seasons (an incidence rate of 288/1,000). Seroconversion was associated with history of febrile illness; severe leptospirosis was not seen. Human exposure to Leptospira in the Iquitos region is high, likely related both to the ubiquity of leptospires in the environment and human behavior conducive to transmission from infected zoonotic sources.  相似文献   
78.
BACKGROUND: Syncope is a common symptom that has different recurrence ratios. We hypothesized that an individualized treatment regimen including pharmacologic and nonpharmacologic measures considering kind of neurocardiogenic syncope (NCS) and basal characteristics of each patient could allow optimized therapy to avoid recurrences. METHODS: We conducted a prospective study to evaluate performance of diverse accepted treatments for NCS. Each patient received specific treatment including general measures such as an increase in salt and water intake, tilt training, specific pharmacologic treatment according to head-up tilt table test (HUTT) result, and patient basal blood pressure and heart rate measurements. RESULTS: We followed a group of 127 patients during a main period of 20.8 +/- 9 months (range, 6-38 months). Mean age was 47.8 +/- 19.2 years and 66.9% were females. We had six (4.7%) patients with recurrence of symptoms 4 +/- 0.9 months after diagnostic HUTT. Medications used were atenolol in 20 patients, pindolol in 17, dysopiramide in 50, and fluoxetine in 25. Two patients received fludrocortisone. Tilt training was not indicated initially for patients with recurrences but was indicated later; to date, these patients have not experienced further episodes. CONCLUSIONS: Increase in water and salt intake, as well as tilt training, showed great value in prevention of syncope recurrences in this specific set of patients. Pharmacologic treatment has an important role, but there is no single medication associated with significant improvement in symptom control.  相似文献   
79.
80.
GIK solutions improve detection of myocardium viability after acute infarction because they could change the metabolic conditions, improving myocardial perfusion defects. METHODS AND RESULTS: Seventy four patients (52 men, 22 women, mean age 53.3.08 +/- 12.14 years) with previous myocardial infarction (evolution time, 4.2 +/- 3.1 months) underwent pharmacological stress (dipyridamole), rest redistribution and reinjection Tl-201 image as well rest/stress Tc-99m Sestamibi, after the intravenous administration of GIK (200 g glucose +/- 30 UI regular insuline +/- 40 mEq potassiumchloride/500 mL in continuous infusion during 3 hours), Group A (N = 22) or oral administration of 70 g of glucose+/- 40 mEq of potassium chloride taking in advantage the endogenous insulin secretion, to non-diabetic patients (group B = GB, N = 26) and group C (GC, diabetic patients N = 26). All of the 74 patients received 10 mg of sublingual Isorbide previous to 25 mCi of Tc99m Sestamibi administration in a different 2 days protocol. A total of 1,480 myocardial segments were assessed and numbered, and the severity of perfusion defects in the segments involved, were compared between Thallium 201 rest reinjection and GIK-MIBI as the main objective of the study. Involved territories number: 4.02 +/- 2.50 vs. 6.88 +/- 2.12, p = 0.005 for AD; 5.2 +/- 1.44 vs. 6.35 +/- 1.11, p = 0.05 for RC and 1.58 +/- 1.01 vs. 2.05 +/- 1.05, p = 0.05 Cx. For GIK-MIBI vs. Tl-201 reinjection respectively, and defect severity: 8.2 +/- 6.04 vs. 13.22 +/- 5.38, p = 0.01 for LAD; 11.72 +/- 5.08 vs. 15.13 +/- 4.42, p = 0.005 for RC and 2.66 +/- 2.09 vs. 4.69 +/- 3.58, p = 0.003 Cx . For GIK-MIBI vs. Tl-201 reinjection respectively, were found. CONCLUSION: Our data suggest that GIK-MIBI protocol is a safe and easy procedure which improves the detection of perfusion reversible defects compared with Tl-201 reinjection, obtaining better information regarding myocardial viability, with lower acquisition time and less cost.  相似文献   
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