全文获取类型
收费全文 | 2101篇 |
免费 | 93篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 25篇 |
儿科学 | 32篇 |
妇产科学 | 7篇 |
基础医学 | 330篇 |
口腔科学 | 57篇 |
临床医学 | 179篇 |
内科学 | 510篇 |
皮肤病学 | 38篇 |
神经病学 | 183篇 |
特种医学 | 62篇 |
外科学 | 216篇 |
综合类 | 1篇 |
预防医学 | 86篇 |
眼科学 | 47篇 |
药学 | 129篇 |
中国医学 | 1篇 |
肿瘤学 | 300篇 |
出版年
2023年 | 6篇 |
2022年 | 24篇 |
2021年 | 49篇 |
2020年 | 20篇 |
2019年 | 29篇 |
2018年 | 46篇 |
2017年 | 43篇 |
2016年 | 46篇 |
2015年 | 40篇 |
2014年 | 55篇 |
2013年 | 70篇 |
2012年 | 117篇 |
2011年 | 131篇 |
2010年 | 67篇 |
2009年 | 81篇 |
2008年 | 117篇 |
2007年 | 117篇 |
2006年 | 112篇 |
2005年 | 123篇 |
2004年 | 104篇 |
2003年 | 113篇 |
2002年 | 116篇 |
2001年 | 31篇 |
2000年 | 38篇 |
1999年 | 41篇 |
1998年 | 31篇 |
1997年 | 37篇 |
1996年 | 36篇 |
1995年 | 24篇 |
1994年 | 28篇 |
1993年 | 19篇 |
1992年 | 28篇 |
1991年 | 28篇 |
1990年 | 13篇 |
1989年 | 15篇 |
1988年 | 30篇 |
1987年 | 19篇 |
1986年 | 11篇 |
1985年 | 31篇 |
1984年 | 7篇 |
1983年 | 8篇 |
1982年 | 7篇 |
1981年 | 13篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1977年 | 7篇 |
1974年 | 8篇 |
1972年 | 10篇 |
1971年 | 10篇 |
1969年 | 8篇 |
排序方式: 共有2203条查询结果,搜索用时 15 毫秒
1.
2.
Yasuhiko Tamada Kikuka Yokochi Yoshimi Oshitani Yukiko Nitta Toshihiko Ikeya Kazuo Hara Katsushi Owaribe 《The Journal of dermatology》1995,22(3):201-204
We report a 73-year-old woman with typical clinical, histological and immunofluorescence features of pemphigoid nodularis. Direct immunofluorescence studies of prurigo nodularis-like lesions and peribullous skin showed the linear deposition of IgG and C3 at the basement membrane zone. Circulating IgG against the basement membrane was also detected by indirect immunofluorescence. The serum from the patient was shown to contain the autoantibody against 230 kDa hemidesmosomal antigen associated with bullous pemphigoid antigen. 相似文献
3.
Shigeharu Kimura Yoshimi Ohshige Liping Lin Tadashi Okumura Chizuko Yanaihara Noboru Yanaihara† Yahe Shiotani 《Journal of neuroendocrinology》1994,6(5):503-507
The localization of pituitary adenylate cyclase-activating polypeptide (PACAP) in the hypothalamus-pituitary system in rats was examined in light and electron microscopic immunocytochemistry using a specific antiserum to synthetic PACAP 1–38 (R0831). In light microscopic study, intensely PACAP-immunostained perikarya were observed in the supraoptic and paraventricular magnocellular nucleus in the hypothalamus. In the median eminence, many immunoreactive nerve fibers were observed in the internal layer, but a few immunoreactive terminals were noticed in the external layer. In the pituitary gland, numerous immunoreactive nerve fibers were observed in the posterior lobe. In the intermediate lobe, moderately immunostained cells were observed, but in the anterior lobe no immunostained cells were noticed. In electron microscopic study, PACAP-immunoreactivity was examined by avidin-biotin peroxidase complex method. In the perikarya of the supraoptic and paraventricular magnocellular nucleus, DAB-reaction products were distributed diffusely in the cytoplasmic matrix, frequently attaching to the rough-surfaced endoplasmic reticulum. In the nerve terminals of the posterior lobe, reaction products were observed among the secretory granules, but sometimes upon them. In the cells of the intermediate lobe, reaction products were also distributed in the cytoplasmic matrix. 相似文献
4.
Kenji Yoshimi Masatoshi Takeda Tsuyoshi Nishimura Takashi Kudo Yu Nakamura Kunitoshi Tada Nobuyoshi Iwata 《Brain research》1991,560(1-2):149-158
Changes in MAP2 and clathrin immunoreactivity were studied in gerbil hippocampus after transient cerebral ischemia. MAP2 immuno-reactivity decreased significantly by 1 h in the subiculum-CA1 and CA2 areas which correspond to reactive change, while no decrease was observed in CA1 until day 4. Before the initiation of delayed neuronal death, MAP2 immunoreactivity was not changed in CA1. On the other hand clathrin immunoreactivity increased in the pyramidal cell layer of CA1 by 3 h after ischemia and remained high for 2 days. Clathrin immunoreactivity in the pyramidal cell layer of CA1 diminished after delayed neuronal death. The transient change of clathrin was noted especially in CA1 in the period prior to delayed neuronal death. These results imply an abnormal change in clathrin turnover after ischemia, which may participate in the pathogenesis of delayed neuronal death. 相似文献
5.
Sugie Shigeyuki; Yoshimi Naoki; Tanaka Takuji; Mori Hideki; Williams Gary M. 《Carcinogenesis》1994,15(1):95-98
The nuclear pore density and area were measured on freeze-fracturednuclei of ACI/N rat liver altered foci, adenomas and carcinomasinduced by 2-acetylaminofluorene, and compared with those ofnormal hepatocytes. The pore density of nuclei from these preneoplasticand neoplastic lesions was significantly higher than that ofhepatocytes, but there was no difference between lesions. Thearea of nuclear pores of the focus cells did not differ fromnormal hepatocytes, whereas the areas of pores of adenoma andcarcinoma cells were increased. Moreover, the nuclear pore areaof carcinomas was significantly greater than that of adenomas.These results suggest that some changes may occur in nuclearpores in the progress of tumorigenesis. 相似文献
6.
Masaki Shinoda Tsuyoshi Yamaguchi Yoshimi Tanaka Osamu Sato Sin Kobayashi Yutaka Suzuki 《Child's nervous system》1992,8(4):219-221
Single photon emission computerized tomography (SPECT) is now widely used as one of the tools in evaluating cerebral blood flow (CBF). The authors report the CBF changes in childhood hydrocephalus. Five pediatric cases studied by 123I-IM SPECT in children are presented. The authors counted radioactivities both in early and delayed images in each patient, and calculated the reabsorption ratio (RR). Two negative-RR cases and three positive-RR cases were found. All of the negative-RR patients had a poor prognosis, while all of the positive-RR patients had a favorable outcome. 相似文献
7.
Potentiation of allergic bronchoconstriction by repeated exposure to formaldehyde in guinea-pigs in vivo 总被引:2,自引:0,他引:2
T. Kita M. Fujimura S. Myou Y. Ishiura M. Abo N. Katayama M. Nishitsuji Y. Yoshimi S. Nomura Y. Oribe S. Nakao 《Clinical and experimental allergy》2003,33(12):1747-1753
BACKGROUND: Indoor formaldehyde (FA) might worsen allergies and be an underlying factor for the increasing incidence and severity of asthma; the exact mechanism, however, remains unclear. OBJECTIVE: The present study examined the effects of repeated exposure to FA on methacholine- and antigen-induced bronchoconstriction in guinea-pigs in vivo. METHODS: First, non-sensitized guinea-pigs were transnasally treated with 0.1 or 1.0% FA or saline three times a week for 6 weeks, and increasing concentrations of methacholine (50, 100, and 200 microg/mL) were inhaled at 5-min intervals. Second, guinea-pigs pre-treated with transnasal administration of FA or saline using the same protocol were passively sensitized with anti-ovalbumin (OA) serum 7 days before antigen challenge. Third, guinea-pigs were actively sensitized with OA and pre-treated with transnasal administration of FA or saline using the same protocol. The lateral pressure of the tracheal tube (Pao) was measured under anesthesia and artificial ventilation. RESULTS: The antigen-induced increase in Pao in actively sensitized guinea-pigs was significantly potentiated by FA exposure in a dose-dependent manner. The dose-response curve of the methacholine-induced increase in Pao in non-sensitized guinea-pigs or of the antigen-induced increase in Pao in passively sensitized guinea-pigs was not altered by FA exposure. Transnasal administration of FA significantly increased the serum anti-OA homocytotropic antibody titre (IgG) as measured by the passive cutaneous anaphylaxis reaction in actively sensitized guinea-pigs. CONCLUSION: The results suggest that repeated exposure to FA worsens allergic bronchoconstriction through enhancing antigen sensitization. 相似文献
8.
Tadaaki Yokota Tokuhiro Ishihara Hiroo Kawano Mutsuo Takahashi Yoshimi Yamashita Toshikazu Gondo Yoshihiro Fujinaga Fumiya Uchino 《Pathology international》1989,39(6):349-355
Amyloid enhancing factor (AEF) was extracted from spleens of mice that had received amyloidogenic stimulation. Sephacryl S 300 gel filtration of the crude AEF yielded five fractions, among which strong AEF activity was present in the first peak (Fl), and confirmed by an amyloid induction experiment. An anti AEF antiserum was obtained from a rabbit by immunization with Fl. This antibody reacted strongly with splenic polymorphonuclear leukocytes (PML) from mice given amyloidogenic stimulation, and weakly with those from normal untreated mice. Isoelectric focusing (IEF) analysis of both Fl and sera from mice given amyloidogenic stimulation was performed. A single band was observed on IEF analysis of Fl, whereas many bands were seen on IEF analysis of the sera. After the substances in the gel had been transferred to nitrocellulose membranes by capillary blotting, the membranes were made to react with the anti-AEF antiserum. The results suggested that AEF is a high molecular-weight substance derived from PML and increases in the serum at the time of, or shortly prior to, amyloid deposition in the spleen. Acta Pathol Jpn 39: 349∼355, 1989. 相似文献
9.
Kinetic profiles of sequential gene expressions for chemokines in mice with contact hypersensitivity
Using cDNA microarray technology, the expression of chemokine genes in the elicitation site of 2,4,6-trinitrochlorobenzene-induced contact hypersensitivity (CHS) was examined in mice. Of the 33 genes analyzed, levels of 11 gene expressions changed, and these can be assigned to four groups based on their kinetic patterns; (1) LARC/CCL20 whose mRNA level increased rapidly at 3 h post-challenge and then gradually decreased, (2) JE/CCL2, MARC/CCL7, MIP-1gamma/CCL9, monocyte chemoattractant protein (MCP)-5/CCL12, ELC/CCL19 and BRAK/CXCL14 whose mRNA levels increased with time and reached the maximum at 6-9 h post-challenge, (3) LIX/CXCL5, Mig/CXCL9 and IP-10/CXCL10 whose mRNA levels increased gradually at least up to 12 h post challenge, and (4) SLC/CCL21 whose mRNA level decreased gradually with time after challenge. The findings suggest that sequential expression of chemokine genes is essential for orientating non-specific skin response to hapten-specific CHS response through the recruitment of inflammatory cells such as neutrophils, monocytes/macrophages and T-cells from the circulation into the tissue site. 相似文献
10.
Ryszard Grucza Yoshimi Miyamoto Yoshimi Nakazono 《European journal of applied physiology》1990,61(3-4):230-236
Summary Kinetics of cardiorespiratory response to dynamic (DE) and then to rhythmic-static exercise (RSE) was compared in nine male subjects exercising in an upright position on a cycle ergometer at an intensity of about 50 %
O2max and a mean pedalling frequency of 60 rpm over 5 min. Respiratory frequency (f
R), tidal volume (V
T), minute ventilation (
E), heart rate (f
c), stroke volume (SV), and cardiac output (Q
t) were measured continuously. The RSE caused a greater increase in f
R than DE, whereas V
T increased more during DE. The effect of reciprocal changes in f
R and V
T was that
E and its kinetics, expressed as a time constant (), did not differ between experimental situations. The ventilatory equivalent for O2 (
E:
O2) was greater for RSE (31.3) than for DE (23.0, P<0.01). Elevation of f
c was similar for both types of exercise. The SV increased suddenly at the beginning of DE from 54 ml to 74 ml and then decreased to the end of exercise. At the onset of RSE only a moderate increase in SV was observed, from 56 ml to 62 ml, and then SV remained stable. The DE caused a greater and faster increase in Q
t (4.20 l · min–1, for equal to 16.1s) than RSE (3.25 l · min–1, for equal to 57.0s, P<0.05 and P<0.002, respectively). Total peripheral resistance was almost 40% greater for RSE than for DE. No relationship was found between Q
t and VE at the first 15 s of both types of exercise. It is concluded that the kinetics of
E did not depend on to kinetics of Q
t in the exercising subjects. This finding contradicts the hypothesis of cardiodynamic hyperpnoea indicating an importance of neurogenic factors, mediated either centrally or peripherally, in fast cardiorespiratory responses to exercise. 相似文献