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1.
Measurements of respiratory mechanics are frequently made in ventilated infants and children. Esophageal pressure measurements (Pes using a balloon on a catheter have been used to partition the respiratory mechanics into lung and chest wall components. Appropriate positioning of this balloon is crucial to obtain accurate estimates of pleural pressure. Traditionally, in spontaneously breathing subjects the balloon position is assessed with an occlusion test. In ventilated subjects, it is not always possible to perform an occlusion test prior to paralysis, and even if such a test is performed it may not be relevant under conditions of positive pressure ventilation. We have assessed a positive pressure occlusion test that is suitable for paralyzed subjects. By occluding the airway opening and applying gentle pressure to the abdomen or rib cage, positive swings in pressure can be measured by both Pes and airway opening pressure (Pao). We compared traditional occlusion tests measured in 16 spontaneously breathing puppies to the positive pressure occlusion test performed after paralysis. In 2 pups we were unable to obtain a reasonable traditional occlusion test (>15% difference between Pes and Pao) but we obtained 10 traditional occlusion tests in each of the remaining 14 pups (2.1–14 kg). In 11 of these animals Ape, was within 10% of Pao. This compared well to positive pressure occlusion test using abdominal pressure performed after paralysis, where Apes was within 10% of ΔPao in 10 animals. In 9 of these pups occlusion tests were also performed by applying pressure on the rib cage, where ΔPes was within 10% of ΔPao in 6 animals. These results suggest that it is possible to perform accurate occlusion tests in paralyzed subjects by abdominal or rib cage compression with the airway occluded. Pediatr Pulmonol. 1994; 17:56–62. © 1994 Wiley-Liss, Inc. 相似文献
2.
Decreased response of beta-adrenergic receptor has been considered to he one of the causes of increased responsiveness of the bronchi in asthma. Since beta-adrenergic receptor has two subtypes, beta1 and beta2 , and the bronchodilating effect of beta stimulants is mediated by beta2 -receptor, responsiveness of the bronchi is expected to correlate to the cyclic AMP response of lymphocytes to a beta2 -stimulant. Responsiveness of the bronchi was expressed as respiratory threshold to acetylcholine (RT-Ach), which was the minimal concentration of acetylcholine solution to cause an initial decrease of FEV1 of more than 20% of the baseline value. Beta1 and heta2 -responses were expressed as the increments of cyclic AMP content of 106 lymphocytes incubated with norepinephrine (beta1 -stimulant) and salbutamol (beta2 -stimulant).
RT-Ach showed a significant correlation with the beta2 -cyclic AMP response of lymphocytes, but not with the beta1 -response among patients with asthma. Sixteen symptomatic patients on continuous beta-stimulants showed lower RT-Ach value and diminished beta2 -receptor activity of lymphocytes compared with 14 patients in remission. These results suggest that selective beta2 -adrenergic blockade may he one of the causes of bronchial hypersensitivity in asthma, though it should be noted that in this study beta-adrenergic responses were examined in lymphocytes and were compared with the responsiveneness of the bronchi. Possible beta-receptor subsensitivity induced by administration of beta-stimulants is discussed. 相似文献
RT-Ach showed a significant correlation with the beta
3.
The first two formant frequencies (F1 and F2) are the cues important for vowel identification. In the categorization of the naturally spoken vowels, however, there are overlaps among the vowels in the F1 and F2 plane. The fundamental frequency (F0), the third formant frequency (F3) and the spectral envelope have been proposed as additional cues. In the present study, to investigate the spectral regions essential for the vowel identification, untrained subjects performed the forced-choice identification task in response to Japanese isolated vowels (/a, o, u, e, i/), in which some spectral regions were deleted. Minimum spectral regions needed for correct vowel identification were the two regions including F1 and F2 (the first and fourth in the quadrisected F1-F2 regions in Bark scale). This was true even when phonetically different vowels had a similar combination of F1 and F2 frequency components. F0 and F3 cues were not necessarily needed. It is concluded that the relative importance in the spectral region is not equivalent, but weighted on the two critical spectral regions. The auditory system may identify the vowels by analyzing the information of the spectral shapes and the formant frequencies (F1 and F2) in these critical spectral regions. 相似文献
4.
Yuji Oto Nobuyuki Murakami Keiko Matsubara Sohei Saima Hiroyuki Ogata Hiroshi Ihara Toshiro Nagai Tomoyo Matsubara 《American journal of medical genetics. Part A》2020,182(4):659-663
It is unclear whether hypothyroidism is present in patients with Prader–Willi syndrome (PWS). This study aimed to clarify the state of the hypothalamic–pituitary–thyroid axis and the effects of growth hormone (GH) treatment on thyroid function in pediatric patients with PWS. We retrospectively evaluated thyroid function in 51 patients with PWS before GH treatment using a thyroid‐releasing hormone (TRH) stimulation test (29 males and 22 females; median age, 22 months). We also evaluated the effect of GH therapy on thyroid function by comparing serum free triiodothyronine (fT3), free thyroxine (fT4), and thyroid stimulating hormone (TSH) levels at baseline, 1 year, and 2 years after GH therapy. TSH, fT4, and fT3 levels were 2.28 μU/ml (interquartile range [IQR]; 1.19–3.61), 1.18 ng/dl (IQR; 1.02–1.24), and 4.02 pg/dl (IQR; 3.54–4.40) at baseline, respectively. In 49 of 51 patients, the TSH response to TRH administration showed a physiologically normal pattern; in two patients (4.0%), the pattern suggested hypothalamic hypothyroidism (delayed and prolonged TSH peak after TRH administration). TSH, fT4, and fT3 levels did not change significantly during 1 or 2 years after GH treatment. The TSH response to TRH showed a normal pattern in most patients, and thyroid function did not change significantly during the 2 years after initiating GH treatment. 相似文献
5.
Sohei Kitazawa Sakan Maeda Taketoshi Sugiyama 《Medical oncology (Northwood, London, England)》1990,7(1):35-41
We raised monoclonal antibody (MAb) against a synthetic oligopeptide corresponding to a portion of the predictedv-abl protein sequence (379–390). This MAb reacted with all of theabl-gene products (pl45c-abl, pl50c-abl and 210bcr-abl fused protein) and was not specific for any one of them. Immunocytochemically, we investigated the expression and localization of theabl-gene products in various leukemic cell lines. Positive immunoreactions were observed in Ph1 positive leukemic cell lines (K562 and KU-812) and erythro-leukemic cell lines (HEL and K3D) and were located on the cell membrane. Electron microscopically, a different distribution pattern was observed among the cell lines: linear and almost even in Ph1 positive leukemic cell lines, whereas spotted or budding-like in erythroleukemic cell lines. Ph1 translocation produces p210nbcr-abl fused protein with not only altered autophosphorylation activities but also altered subcellular distribution patterns. 相似文献
6.
Increased nitric oxide production in hepatocytes is involved in liver dysfunction following obstructive jaundice 总被引:7,自引:0,他引:7
Tu W Kitade H Satoi S Zhang ZT Kaibori M Kwon AH Kamiyama Y Okumura T 《The Journal of surgical research》2002,106(1):31-36
BACKGROUND: Obstructive jaundice damages critical functions in the liver. However, the mechanisms involved in hepatic dysfunction are obscure. Nitric oxide is implicated in liver injury under various pathological conditions. We previously reported that proinflammatory cytokine interleukin-1beta (IL-1beta) stimulated the production of nitric oxide in hepatocytes, which was associated with mitochondrial dysfunction. Studies were performed to examine whether obstructive jaundice influences the production of nitric oxide in hepatocytes and alters hepatic energy metabolism. MATERIAL AND METHODS: Hepatocytes were isolated and cultured from a rat model of obstructive jaundice or sham control. Nitric oxide production, ATP content, and ketone body ratio (acetoacetate/beta-hydroxybutyrate; KBR) were compared between the two groups in the presence of IL-1beta. RESULTS: Hepatocytes obtained from obstructive jaundice rats markedly increased the levels of nitric oxide production stimulated by IL-1beta compared with those from sham control. Western blot analysis revealed that the enhancement of nitric oxide production was a posttranslational event, since protein levels of inducible nitric oxide synthase (NOS) were unchanged between the two groups. IL-1beta decreased cellular ATP content in obstructive jaundice but not in sham control. Further, the KBR, which is a marker of mitochondrial redox state, was lower in obstructive jaundice than in sham control. Addition of N(G)-monomethyl-L-arginine, an inhibitor of NOS, abolished the decreases in ATP content and KBR as well as the nitric oxide production. CONCLUSIONS: These results indicate that a priming of nitric oxide production following obstructive jaundice is associated with the alteration of hepatic energy metabolism in part through mitochondrial dysfunction. Regulation of nitric oxide production may be a useful therapy for preventing liver dysfunction in obstructive jaundice. 相似文献
7.
Systematic review of coexistent epileptic seizures and Alzheimer's disease: Incidence and prevalence
8.
9.
Miku Nakagawa Riko Kitazawa Takeshi Kondo Kosuke Ninomiya Masayoshi Okita Ryuma Haraguchi Sohei Kitazawa 《Virchows Archiv : an international journal of pathology》2014,464(3):253-256
Duodenal gastric heterotopia (DGH) is a benign asymptomatic condition assumed to be of congenital origin. Since DGH is often associated with fundic gland polyps (FGPs) that frequently carry a somatic β-catenin gene mutation, we examined whether DGH, either sporadic or FGP-associated, is attributable to alterations of the Wnt/β-catenin pathway. Genetic analysis revealed frequent somatic β-catenin gene mutations in DGH; some of which showed the same mutation pattern as coexisting FGPs. All missense mutations were confined to codons 32, 33, and 37. No such mutations were observed, however, in any of the specimens from focal gastric foveolar metaplasia (GFM). Therefore, DGH is not a mere congenital lesion due to aberrant migration of normal gastric mucosa or a simple reactive metaplasia after regenerative stimuli of the duodenal mucosa, but a distinct condition based upon molecular genetic changes in the Wnt/β-catenin pathway. 相似文献
10.
Kazuhiro Migita MD Tomoyoshi Takayama MD Keigo Saeki MD Sohei Matsumoto MD Kohei Wakatsuki MD Koji Enomoto MD Tetsuya Tanaka MD Masahiro Ito MD Norio Kurumatani MD Yoshiyuki Nakajima MD 《Annals of surgical oncology》2013,20(8):2647-2654