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81.
82.
The 1.5 GHz Electromagnetic Near-field Used for Cellular Phones Does Not Promote Rat Liver Carcinogenesis in a Medium-term Liver Bioassay 总被引:3,自引:1,他引:3
Katsumi Imaida Masao Taki So-ichi Watanabe Yoshitsugu Kamimura Takayasu Ito Tsuyoshi Yamaguchi Nobuyuki Ito Tomoyuki Shirai 《Cancer science》1998,89(10):995-1002
We have recently established that local exposure to a 929.2 MHz electromagnetic near-field, used for cellular phones, does not promote rat liver carcinogenesis in a medium-term bioassay system. In the present study, a 1.439 GHz electromagnetic near-field (EMF), another microwave band employed for cellular phones in Japan, was similarly investigated. Time division multiple access (TDMA) signals for the Personal Digital Cellular (PDC) Japanese cellular telephone standard system were directed to rats through a quarter-wavelength monopole antenna. Numerical dosimetry showed that the peak SARs within the liver were 1.91–0.937 W/kg, while the whole-body average specific absorption rates (SARs) were 0.680–0.453 W/kg, when the time-averaged antenna radiation power was 0.33 W. Exposure was for 90 min a day, 5 days a week, over 6 weeks, to male F344 rats given a single dose of diethylnitrosamine (200 mg/kg, i.p.) 2 weeks previously. At week 3, all rats were subjected to a two-thirds partial hepatectomy. At week 8, the experiment was terminated and the animals were killed. Carcinogenic potential was scored by comparing the numbers and areas of the induced glutathione S-transferase placental form (GST-P)-positive foci in the livers of exposed (48) and sham-exposed rats (48). Despite increased serum levels of corticosterone, adrenocorticotropic hormone (ACTH) and melatonin, the numbers and the areas of GST-P-positive foci were not significantly altered by the exposure. These findings clearly indicated that local body exposure to a 1.439 GHz EMF, as in the case of a 929.2 MHz field, has no promoting effect on rat liver carcinogenesis in the present model. 相似文献
83.
Nobukazu Fujimoto Yoshihiko Segewa Nagio Takigawa Ichiro Takata Katsuyuki Hotta Hiroshi Mogami Masao Nakata Koichi Mandai Kenji Eguchi 《Lung cancer (Amsterdam, Netherlands)》1998,20(3):203-209
We present two cases of intrapulmonary lymph node. The patients were a 44-year-old woman and a 71-year-old man each with a small peripheral nodule in the lung. On computed tomography (CT) scans, both nodules were spiculated. Since histological diagnosis could not be obtained by bronchoscopic examination or CT-guided needle biopsy, they underwent video-assisted thoracoscopic surgery. Histological examination of the resected material revealed that both nodules were composed of lymph node. Intrapulmonary lymph node has until recently been assigned no clinical significance; however, differential diagnosis of this lesion from lung cancers and other metastatic tumors is now clinically important. 相似文献
84.
Kazushige Kiguchi Masao Iwamori Yukari Mochizuki Takeshi Kishikawa Katsumi Tsukazaki Masahiko Saga Akira Amemiya Shiro Nozawa 《Cancer science》1998,89(9):923-932
Cells of the human tumor cell line RMG-1, derived from a clear-cell adenocarcinoma of the ovary, were injected intraperitoneally into nude mice, and the cells obtained from the tumor nodules in the mesenterium were found to form a larger number of, and larger-sized, tumor nodules than the original RMG-1 cells. The RMG-1-h cells, transferred into culture from the tumor nodules after a 4th in vivo passage, showed a dissemination potential as high as that of cells disseminating directly from the tissues, and exceedingly higher than that of RMG-1 cells. To assess the molecular bases of the different biological properties of RMG-1 and RMG-1-h cells, we compared the content and expression of various carbohydrate antigens in both cells. The chromosomal profile of RMG-1-h cells revealed their human origin and was identical to that of the original RMG-1 cells. In contrast to the broad histogram for the Lex-bearing cells among RMG-1 cells in flow cytometry, the weakly and moderately positive cells toward anti-Lex antibody were found to be eliminated from the histogram for the RMG-1-h cells, resulting in the enrichment of cells strongly expressing Lex, which may account for the high dissemination potential. In addition, the adhesion of RMG-1 cells to mesothelial cells was found to be significantly inhibited by pretreatment of the cells with anti-Lex antibody, indicating Lex-mediated cell-to-cell interaction between ovarian cancer cells and mesothelial cells. By TLC-immunostaining, two Lex-glycolipids, III3Fucα-nLc4Cer and V3Fucα-nLc6Cer were detected in both RMG-1 and RMG-1-h cells, and their total concentrations were not significantly different from each other. However, the hydrophobic moieties of Lex-glycolipids in RMG-1-h cells were different from those in RMG-1 cells, suggesting that a difference in the structure of the hydrophobic moieties of Lex is partly involved in the enhanced reactivity of RMG-1-h cells toward anti-Lex antibody. Thus, the high dissemination potential of ovarian cancer cells was shown to be mediated by the Lex-determinant and the Lex-bearing cells are enriched by repeated in vivo passage of the cells into nude mice. 相似文献
85.
Shin-ichiro Masunaga M.D. Ph.D. Koji Ono M.D. Ph.D. Yoshinori Sakurai D.Eng. Masao Takagaki M.D. Ph.D. Toru Kobayashi D.Eng. Minoru Suzuki M.D. Yuko Kinashi M.D. Ph.D. Mitsuhiko Akaboshi Ph.D. 《International journal of radiation oncology, biology, physics》1998,41(5):365
Purpose: Response of quiescent (Q) and total tumor cells in solid tumors to neutron irradiation with three different cadmium (Cd) ratios was examined. The role of Q cells in tumor control was also discussed.Methods and Materials: C3H/He mice bearing SCC VII tumors received continuous administration of 5-bromo-2′-deoxyuridine (BrdU) for 5 days using implanted mini-osmotic pumps to label all proliferating (P) cells. Thirty minutes after intraperitoneal injection of sodium borocaptate-10B (BSH), or 3 h after oral administration of dl-p-boronophenylalanine-10B (BPA), the tumors were irradiated with neutrons, or those without 10B-compounds were irradiated with gamma rays. This neutron irradiation was performed using neutrons with three different cadmium (Cd) ratios. The tumors were then excised, minced, and trypsinized. The tumor cell suspensions were incubated with cytochalasin-B (a cytokinesis-blocker), and the micronucleus (MN) frequency in cells without BrdU labeling (Q cells) was determined using immunofluorescence staining for BrdU. The MN frequency in total (P + Q) tumor cells was determined from tumors that were not pretreated with BrdU. The sensitivity to neutrons was evaluated in terms of the frequency of induced micronuclei in binuclear tumor cells (MN frequency).Results: Without 10B-compounds, the MN frequency in Q cells was lower than that in the total cell population. The sensitivity difference between total and Q cells was reduced by neutron irradiation. Relative biological effectiveness (RBE) of neutrons compared with gamma rays was larger in Q cells than in total cells, and the RBE values for low-Cd-ratio neutrons tended to be larger than those for high-Cd-ratio neutrons. With 10B-compounds, MN frequency for each cell population was increased, especially for total cells. This increase in MN frequency was marked when high-Cd-ratio neutrons were used. BPA increased the MN frequency for total tumor cells more than BSH. Nevertheless, the sensitivity of Q cells treated with BPA was lower than that in BSH-treated Q cells. This tendency was clearly observed in high-Cd-ratio neutrons.Conclusion: From the viewpoint of enhancing the Q-cell sensitivity, tumors should be irradiated with high-Cd-ratio neutrons after BSH administration. However, normal tissue reaction remains to be examined because of its low tumor-to-normal tissue and tumor-to-blood biodistribution ratios. 相似文献
86.
从何首乌(PolygonummultiflorumThunb.)的根中分离出11个化合物,根据光谱学分析分别鉴定为:大黄酚(chrysophanol,Ⅰ)、大黄素甲醚(physcione,Ⅱ)、大黄素(emodin,Ⅲ)、ω-羟基大黄素(citreorosein,Ⅳ)、大黄酚8-O-β-D-吡喃葡萄糖苷(chrysophanol8-O-β-D-glucopyranoside,Ⅴ)、大黄素甲醚8-O-β-D-吡喃葡萄糖苷(Physcione8-O-β-D-glucopyranoside,Ⅵ)、大黄素8-O-β-D-吡喃葡萄糖苷(emodin8-O-β-D-glucopyranoside,Ⅶ)、决明酮8-O-β-D-吡喃葡萄糖苷(torachrysone8-O-β-D-glucopyranoside,Ⅷ)、2,3,5,4′-四羟基芪2-O-β-D-吡喃葡萄糖苷(2,3,5,4′-tetrahydroxystilbene2-O-β-D-glucopyranoside,Ⅸ)、没食子酸甲基酯(methylgallate,Ⅹ)和吲哚-3-(L-α-氨基-α-羟基内酸)甲酯[Indole-3-(L-α-amino-α-hydroxypropionicacid)methylester]。其中,化合物Ⅺ为新的天然产物。上述蒽醌和萘类化合物以及芦荟大黄素(aloe-emodin,Ⅻ)、大黄酸(rhein,)、芦荟大黄素8-O-β-D-吡喃葡萄糖苷(aloe-emodin8-O-β-D-glucopyranoside,)、大黄酚8-O-β-D-(6′-O-丙酰基)吡喃葡萄糖苷(chrysophanol8-O-β-D-(6′-O-malonyl)glucopyra- 相似文献
87.
Hiroyuki Sugahara Masao Mizuki Sayoko Matsumae Yoshiko Nabetani Motoko Kikuchi Yuzuru Kanakura 《Infection control and hospital epidemiology》2004,25(1):51-54
OBJECTIVE: To determine whether footwear exchange affects the incidence of febrile neutropenia among patients undergoing chemotherapy for hematologic malignancies. DESIGN: Open trial with historical comparison. SETTING: The 12-bed high-efficiency particulate air-filtered hematology unit at Osaka University Hospital, Suita, Japan. PATIENTS: Those with hematologic malignancies who underwent chemotherapy from January 1997 through January 2003. Footwear exchange was discontinued in January 2000. METHODS: The surveillance system was based on the National Nosocomial Infections Surveillance System of the Centers for Disease Control and Prevention. Rates of febrile neutropenia were calculated for neutropenic patient-days (ie, days with neutropenia < 500/microL). RESULTS: From January 1997 through December 1999 and from February 2000 through January 2003, 58 and 54 patients endured 237 and 184 neutropenic periods following chemotherapy, and their total neutropenic days were 3,123 and 2,503, respectively. They showed episodes of febrile neutropenia 89 and 68 times, respectively. Infection rates were 28.5 and 27.2 per 1,000 neutropenic patient-days (P = .83), respectively. CONCLUSION: The incidence of febrile neutropenia was not affected by footwear exchange. In hematology units, changing shoes does not appear to affect the rate of infections during neutropenic periods. 相似文献
88.
Quality of life among people living with HIV/AIDS in northern Thailand: MOS-HIV Health Survey 总被引:2,自引:0,他引:2
OBJECTIVES: Translation and psychometric evaluation of a Thai version of the Medical Outcomes Study HIV Health Survey (MOS-HIV) in Thailand. METHODS: A cross-sectional survey in Chiang Mai province, northern Thailand, with data collected in face-to-face interviews using a structured questionnaire designed to measure 10 scales of quality of life (QOL). We recruited 200 people with HIV/AIDS attending self-help groups in the municipal area. Standard guidelines were followed for questionnaire translation and psychometric evaluations. RESULTS: Item-level internal consistency and discriminant validity were reasonably established. Success rates were 93.8 and 97.4%, respectively. Scale-level internal consistency reliability of multi-item scales was satisfactory, ranging from 0.74 to 0.88, with all exceeding inter-scale correlations. Principal components analysis of item and scale scores identified two hypothesized dimensions of the MOS-HIV. The mental health component was strongly loaded by health distress, mental health, vitality and cognitive function scales, and physical health by role, physical and social functions, and pain scales. Respondents manifesting symptoms or reporting worsening health status scored significantly lower on all scales. CONCLUSIONS: These preliminary studies have shown the Thai version of the MOS-HIV to have psychometric properties comparable with those reported in previous surveys. Further testing and modification should make it useful as an HIV-specific QOL measure in Thailand. 相似文献
89.
90.
No Improvement of Adult Height in Non-growth Hormone (GH) Deficient Short
Children with GH Treatment
Toshiaki Tanaka Kenji Fujieda Susumu Yokoya Akira Shimatsu Katsuhiko Tachibana Hiroyuki Tanaka Takakuni Tanizawa Akira Teramoto Toshiro Nagai Yoshikazu Nishi Yukihiro Hasegawa Kunihiko Hanew Keinosuke Fujita Reiko Horikawa Goro Takada Masao Miyashita Tadashi Ohno Kazuo Komatsu 《Clinical Pediatric Endocrinology》2006,15(1):15-21
It is still in doubt whether the standard-dose growth hormone (GH) used in Japan (0.5
IU/kg/week, 0.167 mg/kg/week) for growth hormone deficiency is effective for achieving
significant adult height improvement in non-growth hormone deficient (non-GHD) short
children. We compared the growth of GH-treated non-GHD short children with that of
untreated short children to examine the effect of standard-dose GH treatment on non-GHD
short children. GH treatment with recombinant human growth hormone (rhGH) was started
before the age of 11 yr in 64 boys and 76 girls with non-GHD short stature registered at
the Foundation for Growth Science who have now reached their adult height. In 119
untreated boys and 127 untreated girls whose height standard deviation score (SDS) was
below –2 SD at the age of 6 yr, height growth was followed until 17 yr. Height SDS was
significantly lower before GH treatment in the GH-treated group than at the age of 6 yr in
the untreated group, in both sexes. Adult height and adult height SDS were significantly
greater in the untreated group than in the GH-treated group, in both sexes, although the
change in height SDS did not differ significantly. Height SDS was significantly lower
before GH treatment in the GH-treated group than at the age of 6 yr in the untreated
group, so 57 boys and 57 girls whose height SDS at the age of 6 yr in the untreated group
closely matched the height SDS before GH treatment in the GH-treated group were chosen for
comparison. Height SDS did not differ significantly between the GH-treated group before GH
treatment and the untreated group at the age of 6 yr, nor were there differences between
these subgroups in adult height, adult height SDS, or height SDS change, in either sex.
The effect of GH treatment is reported to be dose-dependent and doses over 0.23 mg/kg/week
are reported to be necessary to improve adult height in non-GHD short children. Currently,
the GH dose is fixed at 0.175 mg/kg/week in Japan, and we expected to find, and indeed
concluded, that ordinary GH treatment in Japanese, non-GHD short children does not improve
adult height. 相似文献