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101.
The retinal rod outer segment (ROS) is shed and digested daily by phagosomes in retinal pigment epithelial (RPE) cells. We previously observed significantly fewer large phagosomes in rats fed an alpha-linolenic acid (ALNA)-deficient diet. Rats fed a safflower oil diet (ALNA-restricted) or a perilla oil diet (ALNA-sufficient) through two generations were adapted to a 24-h cycle with light from 0700 to 1900 h. They were killed at 0500, 0900, 1300 and 1700 h to determine the activities of four lysosomal enzymes in retina, including beta-glucosidase, beta-glucuronidase, hexosaminidase and acid phosphatase. The enzyme activities at 0500 h were the lowest and then increased gradually until 1700 h, exhibiting similar circadian rhythms in the two dietary groups. However, the activities at each time point were significantly lower in the safflower group. In the pineal gland, the activities were maximum at 1300 h, except for beta-glucosidase, and were not different between groups. These diets had qualitatively similar but quantitatively different effects on the fatty acid compositions of the retina and the pineal gland. These results indicate that decreased amplitudes in electroretinogram and altered size distribution of phagosomes, as induced by a restricted intake of ALNA, are associated with decreased lysosomal enzyme activities in the retina but not in the pineal gland. 相似文献
102.
Shigemi Onoue Takehito Katoh Yoshihisa Shibata Yasushi Mokuno Katsushi Yoshida Satoshi Kamiya Tetsuya Abe Kiyoshi Hiramatsu Minoru Esaki Haruhiko Chigira 《International journal of clinical oncology / Japan Society of Clinical Oncology》1997,2(2):121-124
We report a case of a long-term survivor with malignant melanoma of the anus who did not undergo radical surgery. A 71-year-old
woman who presented with anal bleeding and anal tumor underwent an excisional biopsy in September 1985. The biopsy specimen
was a lobulated, polypoid, pigmented mass 2 cm in diameter, that had been located on the anterior wall of the anus. A satellite
nodule 7 mm in diameter was found on the left wall of the anus at the level of the dentate line. Both tumors were histologically
diagnosed as malignant melanoma. The primary tumor was 6 mm thick. Melanoma cells were present microscopically at the cut
end of the rectum. Because of her history of ischemic heart disease, the patient rejected our recommendation that she undergo
radical surgery, and received 10 courses of carboplatin 20 mg intramuscularly and OK-432 10 K.E. (Klinische Einheit) intradermally
every week. A single, pigmented metastatic inguinal lymph node developed and was excised in June 1987. A recurrent tumor was
detected in the rectum in October 1992, so again we recommended radical surgery. The patient rejected radical surgery again,
and received 12 courses of carboplatin 10 mg intramuscularly every 2 weeks. She died of disease at home in July 1993 after
surviving for 7 years and 10 months. An autopsy was not performed. This case shows that local excision of the primary lesion
may be appropriate to preserve the quality of life of patients with early-stage malignant melanoma of the anus. 相似文献
103.
Tumor recurrence rate (TRR) and mortality rate (MR) of invasive ductal carcinoma (IDC) of the breast in short-term follow-up are relatively low. Nevertheless, it is extremely important to identify patients at risk of early recurrence or death after surgery. The aim of this study was to establish a new histological prognostic classification scheme for IDC in order accurately to predict the short-term outcome. The following histological parameters were analyzed in 201 IDCs: 1) tumor size, 2) structural atypia, 3) nuclear atypia, 4) number of mitotic figures, 5) fibrotic focus (FF), 6) vascular invasion, 7) tumor necrosis, 8) skin invasion, 9) muscle invasion, 10) nodal status and 11) extramammary fat invasion. Multivariate analysis showed that nuclear atypia, presence of FF, and the invasive length of fat invasion (ILFI) were the most important histological parameters correlated with TRR or MR of IDCs. Accordingly, a new histological classification based on nuclear atypia, FF and ILFI (Nucleus-Fibrotic focus-Fat invasion, NFF) was devised. Comparative studies were performed with the following existing prognostic classifications: 1) histological grade, 2) modified Scarff-Bloom-Richardson histological grade, 3) prognostic index and 4) pathological TNM (pTNM) stage classifications. Patient grouping defined by NFF classification significantly correlated with tumor recurrence or death of IDCs in all cases, cases at stages I and II, those without lymph node metastasis and those who were estrogen receptor (ER)-positive after adjustment for the other four classifications, using multivariate analysis. NFF classification appeared superior to existing prognostic classifications for the accurate prediction of the short-term outcome for patients with IDCs in low risk groups. 相似文献
104.
Conjugated linoleic acid supplementation reduces adipose tissue by apoptosis and develops lipodystrophy in mice 总被引:47,自引:0,他引:47
Tsuboyama-Kasaoka N Takahashi M Tanemura K Kim HJ Tange T Okuyama H Kasai M Ikemoto S Ezaki O 《Diabetes》2000,49(9):1534-1542
Conjugated linoleic acid (CLA) is a naturally occurring group of dienoic derivatives of linoleic acid found in beef and dairy products. CLA has been reported to reduce body fat. To examine the mechanism(s) of CLA reduction of fat mass, female C57BL/6J mice were fed standard semipurified diets (10% fat of total energy) with or without CLA (1% wt/wt). Terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick endlabeling (TUNEL) and DNA fragmentation analysis revealed that fat-mass decrease by CLA was mainly due to apoptosis. Tumor necrosis factor (TNF)-alpha and uncoupling protein (UCP)-2 mRNA levels increased 12- and 6-fold, respectively, in isolated adipocytes from CLA-fed mice compared with control mice. Because it is known that TNF-alpha induces apoptosis of adipocytes and upregulates UCP2 mRNA, a marked increase of TNF-alpha mRNA with an increase of UCP2 in adipocytes caused CLA-induced apoptosis. However, with a decrease of fat mass, CLA supplementation resulted in a state resembling lipoatrophic diabetes: ablation of brown adipose tissue, a marked reduction of white adipose tissue, marked hepatomegaly, and marked insulin resistance. CLA supplementation decreased blood leptin levels, but continuous leptin infusion reversed hyperinsulinemia, indicating that leptin depletion contributes to the development of insulin resistance. These results demonstrate that intake of CLA reduces adipose tissue by apoptosis and results in lipodystrophy, but hyperinsulinemia by CLA can be normalized by leptin administration. 相似文献
105.
106.
Satoshi Yoshinari Shin-ichiro Hamano Manabu Tanaka Motoyuki Minamitani 《European journal of paediatric neurology》2006,10(3):124-128
BACKGROUND: Thyrotropin-releasing hormone (TRH) is now used as a therapeutic agent for various neurological disorders. Animal study has shown that TRH was attributable to increased cerebral blood flow (CBF). AIMS: There have been occasional reports that TRH therapy was effective for improving symptoms of persistent disturbance of consciousness after acute encephalitis or encephalopathy during childhood. To determine whether TRH has an effect on increasing CBF to patients who have consciousness disturbance caused by acute encephalitis or encephalopathy, and to determine the optimal method of administration. METHODS: Sixteen patients aged 0.7-10.9 years (mean age, 3.2+/-3.1 years) who presented with persistent disturbance of consciousness resulting from acute encephalitis or encephalopathy and were treated with TRH. Regional CBF (rCBF) was measured by single photon emission computed tomography before and after TRH therapy. The alteration rates of rCBF were compared between the divided two groups concerning the dose levels, dosing periods, and treatment lags. RESULTS: The alteration rates of rCBF of the high dose group were higher than those of the low dose group. Differences in the dosing periods and treatment lags did not cause any significant difference of the alteration rates of rCBF. CONCLUSION: The study showed that higher alteration rates of the CBF were observed in the higher dosing group, and TRH have the potency of increasing CBF. TRH therapy would have the potential for effective treatment of persistent consciousness disturbance caused by childhood acute encephalitis or encephalopathy. 相似文献
107.
108.
Yoshiaki Ikuta Tetsuya Nakatsura Toshiro Kageshita Satoshi Fukushima Shosuke Ito Kazumasa Wakamatsu Hideo Baba Yasuharu Nishimura 《Clinical cancer research》2005,11(22):8079-8088
PURPOSE: There are no available tumor markers detecting primary melanoma at an early stage. The identification of such serum markers would be of significant benefit for an early diagnosis of melanoma. We recently identified glypican-3 (GPC3) as a novel tumor marker but could diagnose only 40% of melanomas. Thereby, we focused out attention on secreted protein acidic and rich in cysteine (SPARC) overexpressed in melanoma as another candidate for tumor marker. EXPERIMENTAL DESIGN: Secreted SPARC protein was quantified using ELISA in the sera from 109 melanoma patients, five patients with large congenital melanocytic nevus, 61 age-matched healthy donors, and 13 disease-free patients after undergoing a surgical removal. We also quantified GPC3 and 5-S-cysteinyldopa in the same serum samples and compared these markers for their diagnostic value. RESULTS: The serum SPARC concentrations in melanoma patients were greater than those in healthy donors (P = 0.001). When we fixed a cutoff value at the mean concentration plus 2 SD of the healthy donors, the serum SPARC was found to have increased in the sera of 36 of the 109 (33%) melanoma patients, whereas there were three (4.9%) false-positive cases of 61 healthy donors. Surprisingly, 19 of 36 patients showing increased SPARC levels were in stages 0 to II. The serum SPARC level decreased under the cutoff level in 10 of 13 patients after surgical removal. Using SPARC and GPC3 in combination thus enabled us to diagnose 47 of 75 (66.2%) melanoma patients at an early stage (0-II). CONCLUSIONS: SPARC or its combination with GPC3 is thus considered a potentially useful tumor marker, especially for melanoma at an early stage. 相似文献
109.
Intraosseous microcystic meningioma 总被引:2,自引:0,他引:2
Extradural ectopic meningioma is a rare tumor. We report on an example of microcystic meningioma arising in the skull of an
elderly woman. Radiological examination revealed a localized osteolytic lesion in the left parietal bone. At surgery, it was
discovered that the tumor was located within the skull without any evidence of extraosseous extension. The light microscopic,
immunohistochemical and ultrastructural features were consistent with a microcystic variant of meningioma. To our knowledge,
this is the first case of an intraosseous microcystic meningioma, and we believe that this type of meningioma should be considered
in the differential diagnoses of myxoid bone tumors of the calvarium.
Received: 10 January 2000 Revision requested: 21 February 2000 Revision received: 8 March 2000 Accepted: 13 March 2000 相似文献
110.
Repetitive or acute treatment of methamphetamine (MAP) or amphetamine (AMP) induces sensitization to both subsequent challenge treatment of the drugs, and exposure to emotional and physiological stress. In addition, chronic treatment of AMP enhanced DA utilization/release in striatum. Similarly, repetitive exposure to footshock or tail shock stress induces sensitization of noradrenaline or 3-methoxy-4-hydroxyphenylglycol (MHPG) to subsequent mild stress and to small amounts of AMP or MAP injection. Striatum, nucleus accumbens and prefrontal dopaminergic systems have an important role in the development of this sensitization. Immediate early gene (IEG) expression in the hypothalamus, nucleus accumbens and striatum may be involved in this process. Neurobiological vulnerability to schizophrenia may be induced by the interaction of multiple gene disposition and environmental insult, and schizophrenia onset and/or relapse in response to mild, non-specific stress. Stress-sensitive systems therefore are postulated in the pathophysiology of schizophrenia. In this regard, mesolimbic DA systems may be involved in the pathophysiology of schizophrenia. In contrast to MAP- or AMP- and stress-induced sensitization, haloperidol and clozapine induce IEG expression in the caudate-putamen and amygdala. Collectively, MAP- or AMP-induced sensitization may, in part, share an early functional process of neurobiological mechanisms. 相似文献