全文获取类型
收费全文 | 655篇 |
免费 | 19篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 62篇 |
妇产科学 | 8篇 |
基础医学 | 60篇 |
口腔科学 | 12篇 |
临床医学 | 65篇 |
内科学 | 167篇 |
皮肤病学 | 33篇 |
神经病学 | 38篇 |
特种医学 | 1篇 |
外科学 | 77篇 |
综合类 | 3篇 |
预防医学 | 12篇 |
眼科学 | 1篇 |
药学 | 60篇 |
中国医学 | 1篇 |
肿瘤学 | 71篇 |
出版年
2022年 | 4篇 |
2021年 | 6篇 |
2017年 | 4篇 |
2016年 | 7篇 |
2015年 | 8篇 |
2014年 | 11篇 |
2013年 | 15篇 |
2012年 | 4篇 |
2011年 | 4篇 |
2010年 | 10篇 |
2009年 | 14篇 |
2007年 | 12篇 |
2006年 | 37篇 |
2005年 | 16篇 |
2004年 | 16篇 |
2003年 | 10篇 |
2002年 | 5篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 9篇 |
1998年 | 35篇 |
1997年 | 40篇 |
1996年 | 34篇 |
1995年 | 40篇 |
1994年 | 36篇 |
1993年 | 34篇 |
1992年 | 14篇 |
1991年 | 10篇 |
1990年 | 18篇 |
1989年 | 8篇 |
1988年 | 8篇 |
1987年 | 8篇 |
1986年 | 15篇 |
1985年 | 10篇 |
1984年 | 11篇 |
1983年 | 5篇 |
1982年 | 6篇 |
1981年 | 10篇 |
1980年 | 7篇 |
1979年 | 9篇 |
1978年 | 6篇 |
1977年 | 4篇 |
1976年 | 4篇 |
1972年 | 4篇 |
1959年 | 7篇 |
1958年 | 16篇 |
1957年 | 19篇 |
1956年 | 16篇 |
1955年 | 10篇 |
1954年 | 18篇 |
排序方式: 共有674条查询结果,搜索用时 15 毫秒
71.
SHUJI KITAGAWA YOSHIO SUGAYA YOSHIHIKO KASEDA SHINJI SATO 《The Journal of pharmacy and pharmacology》1997,49(5):516-519
Aminocephalosporins with peptide-like structures have been shown to be absorbed by the intestinal peptide carrier. We investigated the transport mechanism of cefdinir, an oral monocarboxylic acid cephalosporin, using rabbit small intestinal brush-border membrane vesicles. Transport of cefdinir showed a slow and almost linear uptake rate for concentrations up to 30 mm with and without an inward H+ gradient. No overshoot phenomenon was observed in the presence of an inward H+ gradient. The uptake rate increased only slightly with decreasing extravesicular pH, and a protonophore had little effect on the uptake. Aminocephalosporins such as cephalexin only slightly inhibited cefdinir uptake even in the presence of an inward H+ gradient, and vice-versa. Monocarboxylic acids such as acetic acid and salicylic acid had little effect on cefdinir uptake. These findings suggest that in contrast with other oral cephalosporins cefdinir uptake through the brush-border membrane is slow and involves a mechanism similar to passive diffusion. 相似文献
72.
The Acute and Chronic Toxicities of Nivalenol in Mice 总被引:5,自引:0,他引:5
RYU JAE-CHUN; OHTSUBO KOHICHIRO; IZUMIYAMA NAOTAKA; NAKAMURA KENICHI; TANAKA TOSHITSUGU; YAMAMURA HISASHI; UENO YOSHIO 《Toxicological sciences》1988,11(1):38-47
The Acute and Chronic Toxicities of Nivalenol in Mice. Ryu,J.-C, Ohtsubo, K., Izumiy-ama, N., Nakamura, JL, Tanaka, T.,Yamamura, H., and Ueno, Y. (1988). Fundam. Appl Toxicol. 11,3847. In an attempt to ascertain precisely the toxiceffects of nivalenol (N1V), we conducted the determination ofLD50 values, and interim kills during the carcinogenic studyin mice. LD50 values (mg/kg) of NIV in 6-week-old male ddY micewere determined as 38.9 (po), 7.4 (ip), 7.2 (sc), and 7.3 (iv).Seven-week-old female C57BL/6CrSlc SPF mice were fed diets containing0, 6, 12, and 30 ppm (mg/kg) NIV over 1 year, and were assessedfor effects on body weight gain, feed efficiency, terminai organweights, hematology, and histopathology. The rates of body weightgain and feed efficiency showed a good dose-dependent correlationin all experimental periods. Gross and histopathological evaluationof the liver, thymus, spleen, kidneys, stomach, adrenal glands,pituitary gland, ovaries, sternum, bone marrow, lymph node,brain, and small intestines with or without Peyer's patch portionfrom control and all NIV-exposed mice revealed that these tissueswere normal in appearance and in histopathological structure.Also, no changes were observed in the ultrastructural studieson the bone marrow. Dietary NIV did, however, cause dose-dependentdecreases of absolute organ weights (mg) and increases of relativeorgan weights (mg/g body weight) in the terminal organ weightsrecorded. A significant leukopenia was observed in the 30 ppmgroup at 6 months and in all NIV-treated groups at 1 year. Nomarked changes were observed in the other hematological parameters.These results indicated that 6 ppm or more of dietary NIV for1 year showed a characteristic toxic effect of trichothecenemycotoxins in mice. 相似文献
73.
TAKUYA WATANABE MD AKIRA MIKAMI MD MASAMICHI MOTONISHI MD HIDEHARU HONDA MD KYOKO KYOTANI MD SHIGEHIKO URUHA MD KIYOJI TERASHIMA MD YOSHIO TESHIMA MD YOSHIRO SUGITA MD 《Psychiatry and clinical neurosciences》1998,52(2):231-232
Abstract Two cases of sleep disordered-breathing in climacteric were reported. Polysomnography including esophageal pressure (Pes) measurement was performed. Case 1 was diagnosed as upper airway resistance syndrome. Case 2 was diagnosed as obstructive sleep apnea syndrome, while many episodes of upper airway resistance also existed. Hormone replacement therapy improved clinical symptoms, and in case 1, Pes nadir was improved but incidence of arousals which was induced by breathing disturbances was not significantly changed. Sleep disordered-breathing should be suspected as a cause of sleep disorder even in females, especially in climacteric age. Pes measurement and evaluation of arousals is required. Hormone replacement therapy may release the upper airway resistance. 相似文献
74.
S. WATANABE E. ICHIKAWA H. TAKAHASHI F. OTSUKA 《The British journal of dermatology》1995,132(5):730-739
The detection of cytokeratins in neoplastic tissues by immunohistochemical methods has numerous diagnostic and investigative applications, because cytokeratins are usually conserved in tumour cells during malignant transformation. Recently, however, it has been reported that progression to malignancy is associated with commencement of expression of low-molecular-weight cytokeratins. In the present study, 42 specimens from 35 cases of squamous cell carcinoma (SCC) of the skin were analysed by immunohistochemical techniques, using polyclonal anti-involucrin antibody and a panel of monoclonal antikeratin antibodies, in order to investigate the nature and differentiation of SCCs. The expression of cytokeratins and involucrin in well-differentiated SCCs was similar to that in normal epidermis. In contrast with well-differentiated SCCs, the expression of differentiation-specific cytokeratins and involucrin was diminished in the immature tumour cells in proportion to the malignancy of the SCCs. Some antibodies, however, stained all tumour cells, irrespective of the degree of malignancy. Furthermore, expression of simple epithelial and non-cornifying stratified squamous epithelial cytokeratins was observed in atypical tumour cells of poorly differentiated SCCs. It is of interest that similar expression was noted in many tumour cells in the lymph node metastases and in some tumour cells in the primary cutaneous lesions. Cytokeratin expression similar to that in normal epidermal keratinocytes was conserved in well-differentiated SCCs, but the expression of cytokeratins changed during progression to malignant transformation. The expression of simple epithelial or non-cornifying stratified squamous epithelial cytokeratins in cutaneous SCCs may be a marker for their capability of invasion and metastatic potential. 相似文献
75.
76.
YASUSHI TAKEDA HIROYOSHI SAWADA HIROFUMI SAWAI TOMOKO TOI-MATSUDA MASARO TASHIMA MINORU OKUMA SHIGEYA WATANABE SEIICHI OHMORI MASAO KONDO 《British journal of haematology》1995,90(1):207-209
Patients with idiopathic acquired sideroblastic anaemia (IASA) usually show macrocytic or normocytic anaemia and increased free erythrocyte protoporphyrin (FEP). The mean cell haemoglobin concentration is normal or slightly low. Here we report a pyridoxine-responsive IASA patient with microcytic and hypochromic anaemia and low FEL level; these features are usually seen in cases of hereditary sideroblastic anaemia. Microcytosis increased during therapy.
There may be a subgroup of IASA with microcytic and hypochromic anaemia, low normal FEP and some response to pyridoxine like hereditary sideroblastic anaemia. 相似文献
There may be a subgroup of IASA with microcytic and hypochromic anaemia, low normal FEP and some response to pyridoxine like hereditary sideroblastic anaemia. 相似文献
77.
Toshifumi HIBI Hiroshi SERIZAWA Masako TOMITA Makoto SUEMATSU Takanori KANAI Noriaki WATANABE Yukio TASHIRO Yoshinori SUGINO Masaharu TSUCHIYA 《Digestive endoscopy》1993,5(2):169-174
Abstract: This case report describes a female patient with Crohn 's disease who had diffuse proctosigmoiditis without a longitudinal ulcer or cobblestone appearance at the initial attack. She was treated with sulfasalazine on the presumptive diagnosis of ulcerative colitis. Two and a half months later, painful ulcers in the oral cavity and a deep longitudinal ulcer in the sigmoid colon were found, and a non-caseous granuloma was revealed in the biopsy specimens taken from the sigmoid colon. A definitive diagnosis of Crohn's disease was established from these findings and treatment with a corticosteroid was effective. 相似文献
78.
YOSHIO HIRAYASU MD HIROKAZU OHTA MD KOZO FUKAO MD CHIKARA OGURA MD JIRO MUKAWA MD 《Psychiatry and clinical neurosciences》1995,49(4):223-226
Abstract Event-related potentials (ERP) were recorded during auditory oddball tasks for a patient prior to and soon after left anterior temporal lobectomy. The N100 amplitude decreased bilaterally although the latency did not change after the lobectomy. The P300 amplitude decreased in the left hemisphere at 1 and 2 weeks after surgery, then recovered to the pre-operative level at 4 weeks. These findings suggest that the medial temporal structure participates in the generating system of P300. 相似文献
79.
MASAYASU OZAKI MASAAKI ISHIKAWA YOSHIO TAKAYANAGI KEN-ICHI SASAKI 《The Journal of pharmacy and pharmacology》1993,45(11):975-978
Abstract— The effects of doxapram on the hepatic microsomal mono-oxygenase system of male and female rats were investigated. Male and female rats were administered doxapram (10–120 mg kg?1 day?1, i.p.) for 4 days. In female rats, administration of doxapram (20, 40, 60, 80, 100 and 120 mg kg?1) elevated the parameters in a dose-dependent manner while doxapram (100 and 120 mg kg?1) elevated the levels of cytochrome P450 and hexobarbitone hydroxylase in male rats. Doxapram (40 mg kg?1) caused induction of hepatic drug metabolism typified by an increase of hepatic microsomal cytochrome P450 content and activities of hexobarbitone hydroxylase, benzphetamine N-demethylase and ethylmorphine N-demethylase in female rats, but no change in male rats. These findings were supported by the results of SDS/polyacrylamide-gel electrophoresis. However, 7-ethoxycoumarin O-de-ethylase and arylhydrocarbon hydroxylase activities were significantly increased in male rats. NADPH-cytochrome c reductase and NADH-cytochrome c reductase activities, and cytochrome b5 content were unaffected in rats of both sexes. The sex-dependent cytochrome P450 species may be selectively sensitive to the action of doxapram. 相似文献
80.