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11.
K-ras activation and ras p21 expression in latent prostatic carcinoma in Japanese men. 总被引:11,自引:0,他引:11
Twenty-three clinically silent prostatic carcinomas discovered in Japanese men at autopsy were surveyed for ras proto-oncogene mutations by mutation-specific oligonucleotide probe hybridization after polymerase chain reaction (PCR) amplification from a section of formalin-fixed, paraffin-embedded tissue. Six of the 22 that were satisfactory amplified contained activating point mutations in codon 12 of K-ras, a significantly higher frequency than has been reported in patients with clinically advanced disease in the United States. Of the six cases with activating point mutations in codon 12 of K-ras, one had a GGT----GAT transition, four had GGT----GTT transversions, and one had both GGT----GAT and GGT----GTT mutations. Sections from the same tissues were immunohistochemically stained with an anti-ras p21 antibody. Carcinoma cells stained for ras p21 to some degree in 13 cases. Immunohistochemically detectable expression of p21 was always focal and was not necessarily associated with K-ras mutation. K-ras oncogene activation in prostatic carcinoma appears to merit additional study as a significant event in the pathogenesis of this neoplasm. 相似文献
12.
M N Hosono K Endo H Sakahara Y Watanabe T Saga T Nakai M Hosono T Nakajima Y Onoyama J Konishi 《Cancer》1992,70(12):2851-2856
BACKGROUND. CA 125 is a representative ovarian cancer-associated antigen defined by monoclonal antibody OC125. Recently, monoclonal antibodies were produced (designated 130-22 and 145-9) that were reactive with CA 125 but bound to a separate epitope named CA 130. There was a close correlation between serum CA 125 and CA 130 values in most instances. However, among more than 8000 serum samples, 5 apparently normal women had high serum CA 125 values, despite having normal CA 130 values. In this study, the antigenic nature of these five women was investigated. METHODS. Using gel chromatography, the molecular masses of CA 125 and CA 130 were estimated that were found in the five women with false-positive CA 125 values. The sera were examined using double-determinant assays combining iodine-125-labeled OC125 or iodine-125-labeled 130-22 with OCI25-coated or 145-9-coated beads. RESULTS. The molecular masses of both CA 125 and CA 130 were estimated as greater than 1000 kilodaltons (KD); the CA 130 mass from one of the five women with an abnormal CA 125 level was approximately 200 KD using gel chromatography. Using the double-determinant assays that combined iodine-125-labeled OC125 or iodine-125-labeled 130-22 with OC125-coated or 145-9-coated beads, high radioactivity was found only in the homologous assay using iodine-125-labeled OC125 with OC125-coated beads. These results suggest that the antigenic nature of CA 125 found in apparently healthy women differs from that found in patients with ovarian cancer and that CA 130 epitopes are not present. CONCLUSIONS. Measurement of serum CA 130 concentrations may be useful for excluding women with falsely elevated CA 125 values. 相似文献
13.
Mariko Hosono H. Kobayashi Ryota Fujimoto Kazushige Tsutsui Yoshihiko Kotoura Tadao Tsuboyama Hikaru Hayashi Takashi Nakamura Junji Konishi 《Skeletal radiology》1997,26(9):525-528
Objective. To clarify the MRI features of parasymphyseal insufficiency fractures of the os pubis. Design and patients. MRI was performed in four postmenopausal women with parasymphyseal insufficiency fractures. The diagnosis was confirmed with
plain films in every patient. T1-weighted and T2-weighted images were obtained in four patients using a 1.5-T unit. Postcontrast
T1-weighted imaging was also done in three patients. Results and conclusions. MRI of pubic parasymphyseal insufficiency fracture characteristically demonstrates a hyperintense mass lesion with a hypointense
rim on T2-weighted imaging, showing peripheral and septal enhancement after contrast administration. It is important to have
this entity in mind in patients with osteoporosis, especially in patients with a history of pelvic irradiation for malignant
disease, so as not to misinterpret it as a chondroid tumor or bone metastasis. 相似文献
14.
M Konishi M Sawaki K Mikasa S Takeuchi K Hamada H Ako M Kunimatsu N Narita 《Nihon Kyōbu Shikkan Gakkai zasshi》1991,29(11):1420-1424
We conducted a clinical study on respiratory infections complicating bronchial asthma. Transtracheal aspiration (TTA) was performed 37 times in 22 patients. The most frequently isolated organism was H. influenzae. The patients in whom organisms were isolated on TTA had a high incidence of fever and evidence of inflammation. Antimicrobial therapy caused a decrease in indices of inflammation (white blood cell count and ESR), but was less effective against the asthmatic symptoms. Respiratory infection may play a complex role in the clinical picture of bronchial asthma. 相似文献
15.
An attempt was made to detect a pancreatic tumor antigen (PTA) in transplantable pancreatic adenocarcinomas induced by N-bis(2-hydroxypropyl)nitrosamine (DHPN) in hamsters. Antibody against antigenic protein was raised by immunizing rabbits with whole homogenate of the tumors transplanted into the back of hamsters. PTA was purified by affinity chromatography and shown to have the physicochemical properties of a glycoprotein with a molecular weight of 800,000, migrating in the beta regions upon agarose gel electrophoresis. Loss of immunological properties was observed after heating at 65 degrees C for 30 min. Enzyme immunoassay revealed that the levels of PTA in the serum and tissue showed a positive correlation with the induction of the presence of tumor, and size of the tumor. It is tentatively suggested that PTA values above 150 ng/ml serum are indicators of tumors, because in normal hamsters the PTA range is from 25 to 130 ng/ml serum. Immunohistochemically, PTA was demonstrated to be localized within the cytoplasm of epithelial tumor cells of well-differentiated tubular adenocarcinomas. 相似文献
16.
Yamamoto Kazuhiko; Nakajima Akira; Eimoto Hiroyuki; Tsutsumi Masahiro; Maruyama Hiroshi; Denda Ayumi; Nii Hiroaki; Mori Yukio; Konishi Yoichi 《Carcinogenesis》1989,10(9):1607-1611
The carcinogenic activity of endogenously synthesized N-nitrosobis(2-hydroxypropyl)amine(BHP) was investigated in male Wistar rats administered bis(2-hydroxypropyl)amine(BHPA) mixed in powder diet at a concentration of 1%, and sodiumnitrite (SN) dissolved in distilled water at concentrationsof 0.15 and 0.3%, for 94 weeks. Urinary excretion of BHP wasdetected in rats given 1% BHPA and 0.3% SN but not in the groupsreceiving either of these precursors alone. Nasal cavity, lung,esophagus, liver and urinary bladder tumors were found in animalstreated with combinations of 1% BHPA and 0.15 or 0.3% SN, suggestingthat the target organs of the endogenously synthesized BHP aresimilar to those affected when the carcinogen is administeredexogenously. The incidences of nasal cavity and lung tumorsreached 74 and 58% in rats given 1% BHPA and 0.3% SN, respectively.Tumors at sites other than target organs were only found atlevels similar to those previously reported for spontaneoustumors in male Wistars. The present results clearly indicatedthe tumor inducibility of a nhrosatable amine, BHA, throughan endogenous nitrosation by feeding to rats in conjunctionwith nitrite, and provide further suggestive evidence that endogenousnitrosations of environmental nitrosatable amines can be a potentialrisk factor in human cancer development. 相似文献
17.
18.
T Nishiyama A Hirasaki Y Odaka H Konishi K Seto I Goto 《Masui. The Japanese journal of anesthesiology》1992,41(1):49-54
Optimal dose of epidural midazolam with saline for postoperative pain relief was investigated. Forty three patients for upper abdominal surgery were divided into 5 groups. Each group had either 10 ml saline only (saline group), 10 ml saline + midazolam 0.025 mg.kg-1 (0.025 group), 10 ml saline + midazolam 0.05 mg.kg-1 (0.05 group), 10 ml saline + midazolam 0.075 mg.kg-1 (0.075 group), or 10 ml saline + midazolam 0.1 mg.kg-1 (0.1 group) administered epidurally for complaint of postoperative pain. Blood pressure (BP), heart rate (HR), respiratory rate (RR) and sedation score (SS) were monitored for 120 minutes, and the time interval for next analgesics (TNA) was checked. In each group, BP was unchanged compared with preinjection level. HR changes were less in 0.05 and 0.1 group than in others. RR changes were less in 0.025 and 0.05 group than in others. Optimal SSs were obtained in 0.025 and 0.05 groups. In 0.075 and 0.1 groups, many patients fell into complete sleep (not responded to verbal command). TNA was about 2 hours in 0.025 and 0.05 groups, over 6 hours in 0.075 and 0.1 groups. Complete sleep was the cause of long TNA in 0.075 and 0.1 groups. It was concluded that optimal dose of epidural midazolam with saline 10 ml was 0.05 mg.kg-1 for postoperative pain relief after upper abdominal surgery. 相似文献
19.
A critical period for estrogen action on neurons of the song control system in the zebra finch. 总被引:3,自引:3,他引:0 下载免费PDF全文
M Konishi E Akutagawa 《Proceedings of the National Academy of Sciences of the United States of America》1988,85(18):7006-7007
The song nuclei of the male zebra finch (Poephila guttata) contain larger neurons than those of the female. This gender difference arises after hatching as a result of cell atrophy in the female and cell growth in the male. Implantation of estrogen in female chicks induces masculine differentiation of neurons in their song nuclei. The effects of estrogen on neuron size decline steeply after posthatching day 35 when neuronal atrophy begins. Estrogen loses its masculinizing effects completely after day 45 when the adult level of neuronal atrophy is reached. Thus, the end and the intensity of hormone action appear to be correlated with the timing of neuronal atrophy. 相似文献
20.
Y Konishi T Hashimoto T Okuno Y Takamine T Tani T Kajiwatra 《Nihon Geka Gakkai zasshi》1992,93(10):1330-1336
US findings of 81 patients with breast cancer were analyzed respectively to evaluate the usefulness of US in the preoperative diagnosis of internal mammary mode metastases. The internal mammary area (I.M.A.) in which internal mammary nodes lie was shown as a hypoechoic stripe in a sagittal scan along the sternum and as a triangular or spindle-shaped hypoechoic area in a transverse scan in the intercostal space. The US features of each I.M.A. in the first three intercostal spaces were divided into three patterns: Pattern-A wad defined as widening of the ipsilateral side of the I.M.A. compared with the contralateral side; Pattern-C was defined as normal at both sides of the I.M.A. Pathological examination confirmed the node metastases in 85.7% of intercostal scans showing Pattern-A and in 35% of intercostal scans showing Pattern-B. Only one of 189 intercostal scans showing Pattern-C had nodal metastases. The overall accuracy was 88.1% in 243 intercostal scans and 90.1% in 81 patients. We conclude that US is useful in the detection of internal mammary node metastases in patients with breast cancer. 相似文献