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11.
12.
Rapid turnover of the W chromosome in geographical populations of wild silkmoths, Samia cynthia ssp.
Atsuo Yoshido Jindra Šíchová Svatava Kubíčková František Marec Ken Sahara 《Chromosome research》2013,21(2):149-164
Our previous studies revealed a considerably high level of chromosomal polymorphism in wild silkmoths, Samia cynthia ssp. (Lepidoptera: Saturniidae). Geographical populations of this species complex differ in chromosome numbers and show derived sex chromosome systems including Z0/ZZ in S. cynthia ricini (2n?=?27/28; Vietnam), neo-Wneo-Z/neo-Zneo-Z in S. cynthia walkeri (2n?=?26/26; Sapporo, Hokkaido) and neo-WZ1Z2/Z1Z1Z2Z2 in S. cynthia subsp. indet. (2n?=?25/26; Nagano, Honshu). In this study, we collected specimens of S. cynthia pryeri in Japanese islands Kyushu, Shikoku and Honshu, with an ancestral-like karyotype of 2n?=?28 in both sexes and a WZ/ZZ sex chromosome system, except for one population, in which females have lost the W chromosome. However, the S. cynthia pryeri W chromosome showed a very unusual morphology: It was composed of a highly heterochromatic body, which remained condensed throughout the whole cell cycle and of a euchromatin-like “tail.” We examined molecular composition of the W and neo-W chromosomes in S. cynthia subspecies by comparative genomic hybridisation and fluorescence in situ hybridisation with W chromosome painting probes prepared from laser-microdissected W chromatin of S. cynthia pryeri. These methods revealed that the molecular composition of highly heterochromatic part of the S. cynthia pryeri W chromosome is very different and lacks homology in the genomes of other subspecies, whereas the euchromatin-like part of the W chromosome corresponds to a heterochromatic part of the neo-W chromosomes in S. cynthia walkeri and S. cynthia subsp. indet. Our findings suggest that the curious WZ system of S. cynthia pryeri may represent an ancestral state of the Samia species complex but do not exclude an alternative hypothesis of its derived origin. 相似文献
13.
Yoshihiro Shirai Tomoyoshi Okamoto Masaru Kanehira Shinji Onda Fumitake Suzuki Ryusuke Ito Shuichi Fujioka Katsuhiko Yanaga 《International surgery》2015,100(6):1078-1083
Pancreatic B-cell lymphoma is rare; it accounts for 0.2% to 2.0% of extranodal non-Hodgkin lymphoma, and constitutes less than 0.5% of all pancreatic malignancies. Most histologic types of the pancreatic lymphoma are diffuse large B-cell lymphoma, and follicular lymphoma is quite rare. We report here a case of pancreatic follicular lymphoma that was initially detected by acute pancreatitis. This is the first reported case of pancreatic follicular lymphoma presenting with acute pancreatitis. A 71-year-old woman had epigastric and left upper quadrant abdominal pain. Computed tomography (CT) revealed features of acute pancreatitis. After standard therapy for pancreatitis, enhanced CT showed a pancreatic tumor (50 × 35 mm) in the body of the pancreas with gradual enhancement. Endoscopic retrograde cholangiopancreatography and magnetic resonance cholangiopancreatography showed a complete interruption of the pancreatic duct in the body, with mild dilation of the duct in the tail of the pancreas. Endoscopic ultrasonography revealed hypervascularity of the pancreatic tumor. The patient underwent distal pancreatectomy to remove the cause of pancreatitis and to disclose the diagnosis. Histologic examination revealed follicular lymphoma of pancreas. Despite recent improvement in clinical strategies, differential diagnosis between pancreatic lymphoma and pancreatic cancer is still difficult without histologic information. Pancreatic lymphoma should be considered as a differential diagnosis in a patient who initially presents with acute pancreatitis.Key words: Pancreatic lymphoma, Acute pancreatitis, Follicular lymphomaPancreatic B-cell lymphoma is rare; it accounts for 0.2% to 2.0% of extranodal non-Hodgkin lymphoma1 and constitutes less than 0.5% of all pancreatic malignancies.2,3 Most histologic types of pancreatic lymphoma are diffuse large B-cell lymphoma, and follicular lymphoma is quite rare. In addition, acute pancreatitis caused by pancreatic lymphoma is also rare.Despite recent improvements in clinical strategies, differential diagnosis of pancreatic lymphoma with pancreatic cancer or autoimmune pancreatitis (AIP) is still difficult without histologic examination.We report here a rare case of a 71-year-old female with pancreatic follicular lymphoma that initially presented as acute pancreatitis. 相似文献
14.
Nobutoshi Komatsu Utaroh Motosugi Shinya Maekawa Kuniaki Shindo Minoru Sakamoto Mitsuaki Sato Akihisa Tatsumi Mika Miura Fumitake Amemiya Yasuhiro Nakayama Taisuke Inoue Mitsuharu Fukasawa Tomoyoshi Uetake Masahiko Ohtaka Tadashi Sato Yasuhiro Asahina Masayuki Kurosaki Namiki Izumi Tomoaki Ichikawa Tsutomu Araki Nobuyuki Enomoto 《Hepatology research》2014,44(13):1339-1346
15.
Fumi Ohdaira Kazutoshi Nakamura Hideaki Nakayama Makoto Satoh Tetsuro Ohdaira Masami Nakamata Masaki Kohno Akira Iwashima Akira Onda Yoshiaki Kobayashi Katsuya Fujimori Toshio Kiguchi Shuji Izumi Tadaharu Kobayashi Hideo Shinoda Sugata Takahashi Fumitake Gejyo Masaharu Yamamoto 《Sleep & breathing》2007,11(2):93-101
Information on obstructive sleep apnea-hypopnea syndrome (OSAHS) in Japan has been limited. The purposes of this clinical study were to evaluate the demographic characteristics of Japanese OSAHS patients and to assess how demographic factors are associated with OSAHS severity. We analyzed 3,659 OSAHS patients who underwent polysomnographic evaluation between January 2000 and December 2004 at 11 hospitals in Niigata Prefecture, Japan. Data consisted of apnea-hypopnea index (AHI) and demographic characteristics, including sex, age, and body-mass index, for statistical analysis. Levels of obesity were classified according to the WHO criteria. The male-to-female patient ratio for OSAHS was 4.6, and male patients presented more severe OSAHS than female patients. High AHI and a high proportion of moderate to serious OSAHS (AHI > or = 15) were found among the patients in their 30s, as well as female patients in their 70s and male patients in their 80s. The AHI and the proportion of moderate-to-serious OSAHS (AHI > or = 15) were greater in patients classified as underweight than in normal weight patients. In conclusion, there is a higher male predominance in the prevalence of OSAHS, and in both sexes, the results suggest different pathophysiological mechanisms of deteriorating OSAHS between adults under age 55 and adults 55 years or over. In addition, underweight patients exhibit more severe OSAHS than normal weight patients. 相似文献
16.
Fractalkine expression and the recruitment of CX3CR1+ cells in the prolonged mesangial proliferative glomerulonephritis 总被引:11,自引:0,他引:11
Ito Y Kawachi H Morioka Y Nakatsue T Koike H Ikezumi Y Oyanagi A Natori Y Natori Y Nakamura T Gejyo F Shimizu F 《Kidney international》2002,61(6):2044-2057
BACKGROUND: We established the reversible and the prolonged models of mesangial proliferative glomerulonephritis (GN) with anti-Thy 1 antibody 1-22-3. However, the essential factors leading to the prolonged glomerular alterations have not been identified. METHODS: The expressions of several chemokines and cytokines were compared in the reversible and the prolonged models. Expression of fractalkine and the number of the fractalkine receptor CX3CR1-positive cells in the glomeruli in the prolonged model were significantly higher than those in the reversible model. Then, the localization of fractalkine and the characteristics of CX3CR1+ cells were analyzed in glomeruli. To elucidate the significance of the fractalkine expression, we analyzed the expression in the model treated with angiotensin II receptor antagonist, candesartan. RESULTS: Immunostaining of fractalkine was detected on endothelial cells on the fifth day, and fractalkine staining also was detected in the mesangial area on day 14. Major parts of the CX3CR1+ cells in the glomeruli were macrophages, especially ED3+ cells. Candesartan treatment ameliorated the glomerular morphological findings at six weeks after disease induction. Although the treatment did not ameliorate the morphological finding at two weeks, decreased expression of fractalkine and CX3CR1+ were already detected at two weeks in rats treated with candesartan. CONCLUSIONS: Fractalkine expression and the recruitment of CX3CR1+ cells in glomeruli might play an important role in the development of the prolonged disease. These expressions could be predictors of the prolonged disease of the mesangial proliferative glomerulonephritis. 相似文献
17.
Sato H Miida T Wada Y Maruyama M Murakami S Hasegawa H Kuroda T Narita I Nakano M Gejyo F 《Clinica chimica acta; international journal of clinical chemistry》2007,385(1-2):35-42
BACKGROUND: It is uncertain whether atherosclerosis is accelerated in premenopausal and postmenopausal patients with long-term well-controlled systemic lupus erythematosus (SLE). METHODS: We measured the intima-media thickness (IMT) of the carotid arteries and the cardio-ankle vascular index (CAVI) in 39 women with SLE and in age- and sex-matched controls. RESULTS: In the premenopausal state, carotid plaque was detected only in SLE patients (36%). In the postmenopausal state, the maximum IMT was about 2-fold greater in SLE patients than in control subjects (1.3+/-0.7 vs. 0.7+/-0.2 mm, p<0.001). CAVI was higher in both the premenopausal and postmenopausal SLE patients. The serum amyloid A protein (SAA) was higher in SLE patients in the premenopausal state (p=0.025), while remnant like particle-cholesterol (RLP-C), the homeostasis model assessment of insulin resistance (HOMA-IR), and SAA were significantly increased in postmenopausal SLE patients (p=0.001, p<0.001 and p<0.05, respectively). Multiple regression analysis revealed that the maximum IMT was associated with cumulative PSL dosage (p=0.027) and SAA (p=0.074) in the premenopausal SLE patients, and with HOMA-IR (p<0.001) in the postmenopausal SLE patients. CONCLUSION: Atherosclerosis is accelerated in long-term well-controlled SLE. More attention should be given to subclinical inflammation and insulin resistance in the management of SLE patients. 相似文献
18.
Nomura H Nishimori H Yasoshima T Hata F Tanaka H Nakajima F Honma T Araya J Kamiguchi K Isomura H Sato N Denno R Hirata K 《Clinical & experimental metastasis》2002,19(5):391-399
To elucidate the mechanisms of metastasis, we established two sublines HPC-1H5 with a highly liver metastatic cell line and
HPC-1P5a with a highly peritoneal disseminating cell line, which were sequentially selected from the parental pancreatic cancer
cell line HPC-1. Using these three cell lines, we investigated several biological properties and mRNA levels of differentially-expressed
genes involved in cancer metastasis by cDNA macroarray. Microscopic findings for the three cell lines were the same. The tumorigenicity,
in vitro growth ability, motile activity, adhesive activity and the production of IL-8 of metastatic sublines were higher than those
of parental HPC-1 cells. Particularly, HPC-1H5 cells showed clearly higher levels of IL-8 expression and tumors of HPC-1H5
cells grew faster and bigger than those of HPC-1P5a cells. In cDNA macroarray analysis of HPC-1H5 cells, 22 genes were up-regulated
and 44 genes were down-regulated compared with parental HPC-1 cells. In HPC-1P5a cells, 9 genes were up-regulated and 28 genes
were down-regulated compared with parental HPC-1 cells. This study provides a demonstration of global gene expression analysis
of pancreatic cancer cells with liver metastasis and peritoneal dissemination. Furthermore, our results provide a new insight
into the study of liver metastasis and peritoneal dissemination of human pancreatic cancer.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
19.
Structural changes in the developing rat lung were studied by a combined use of light microscopy including immunohistochemistry for a-smooth muscle actin (alpha-SMA) and scanning electron microscopy (SEM) using the KOH-collagenase digestion method. In the embryonic stage (E11-E13), the lung bud appeared as an outgrowth from the ventral wall of the foregut which grew caudally into the splanchnic mesoderm to form a pair of bronchial buds at the end. At E13, the airway smooth muscle cells first appeared around the bifurcation of the trachea. These smooth muscle cells were restricted to the dorsal surface of the tracheal epithelium, suggesting a difference in character between the dorsal and ventral sides of the mesenchymal cells in this region. During the pseudoglandular stage (E13-E18.5), the bronchial buds repeatedly gave off branches in the mesenchymal tissue. The smooth muscle cells in the bronchioles were spindle-shaped and arranged completely circularly around the epithelial tube, except that the terminal bud of bronchioles lacked the smooth muscles. The neck of the terminal bud was constantly surrounded by flat and irregularly-shaped immature smooth muscle cells, representing an early event in the smooth muscle cell differentiation from mesenchymal cells. In the canalicular to saccular stages (E18.5 to birth), the terminals of bronchioles became saccular, thus forming prospective alveolar acini. At birth, the alveolar wall became thinner than before birth, and the individual smooth muscle cells in bronchioles were elongated like a tape. As to the blood vessel differentiation, various sized sinusoidal spaces indicating the primitive blood vessels were already present in the mesenchymal tissue at E11.5. The endothelial cells of these sinusoidal spaces were irregularly shaped and sometimes extended their processes into the lumen. The network of tubular vessels appeared from E14.5. These vessels had tapering ends as well as transluminal trabeculae, suggesting that capillary growth proceeds by both the sprouting and partitioning (i.e., intussusception) of vessels in the pseudoglandular stage. 相似文献
20.
R Sueki S Maekawa M Miura M Kadokura K Komase H Shindo A Kanayama T Ohmori K Shindo F Amemiya Y Nakayama T Uetake T Inoue M Sakamoto N Enomoto 《Journal of medical virology》2012,84(9):1360-1368
The emergence of amino acid or nucleotide substitutions leads to lamivudine resistance in hepatitis B virus (HBV) infected patients. The aim of this study was to investigate whether viral sequences help predict the emergence of lamivudine resistance. The study subjects comprised 59 consecutive patients infected with HBV treated with daily therapy of 100 mg lamivudine. Among those, 32 patients with adequate pretreatment serum preservation were investigated for the correlation between viral amino acid substitutions and the appearance of lamivudine resistance with consideration of clinical background by determining dominant HBV full open reading frames. Viral resistance to lamivudine emerged in 28 of 59 patients (47%) in a median period of 2.45 years. Sequence comparisons of HBV genomes between patients who later developed lamivudine resistance and patients who did not revealed the existence of significant differences between the two groups in the pre‐S1 84 (P = 0.042), pre‐S2 1 (P = 0.017) and 22 (P = 0.015), and polymerase tp 95 (P = 0.046), judged by a log‐rank test. Viral sequence analyses revealed the presence of amino acid substitutions in HBV pre‐S1 and pre‐S2 that may be associated with the emergence of lamivudine resistance during chronic HBV infection. J. Med. Virol. 84:1360–1368, 2012. © 2012 Wiley Periodicals, Inc. 相似文献