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991.
We have administered cis-diamminedichloroplatinum (II) (CDDP) containing thermosensitive liposome and simultaneous hyperthermia into human osteosarcoma cells (OST) and studied the antitumor effects. Experiments were conducted under the following three different culture conditions as follows, (1) drug treatment alone, (2) hyperthermia after drug treatment, and (3) simultaneous hyperthermia and drug treatment. Antitumor effects were estimated by inhibition of DNA synthesis and decrease in cell growth rates. The antitumor action of simultaneous hyperthermia and drug treatments was the most dominant and synergistic among three experimental conditions. Accumulation of cellular platinum from thermosensitive CDDP-liposomes was markedly enhanced by hyperthermia. Flow cytometric analysis of the cell cycle indicated that CDDP-liposomes only under the simultaneous application of hyperthermia released free CDDP, and evoked cell accumulation in S and G 2/M phase. The results suggested that thermosensitive CDDP-liposomes were not taken up into cells by endocytosis, and released free CDDP into culture media under hyperthermia at 42 degrees C. From these, we have concluded that administration of thermosensitive CDDP-liposomes and simultaneous local hyperthermia could be a promising method for the treatment of osteosarcoma especially in the extremities.  相似文献   
992.
A 23-year-old man, complaining of a discomfort in the chest, saw a physician nearby and was pointed out chest abnormal shadow in chest X-ray. He was admitted to our hospital for surgery. As a result of a close check-up at this department, a giant tumor extending from above the right diaphragm to the posterior mediastinum was found. Physical findings in the preoperative examination and general examinations showed no abnormality. The operation was performed and was diagnosed as paraganglioma. This tumor is abundant in blood vessels. Thus, preoperative angiography and securing of the field of operation in treating the blood vessels were considered indispensable for the safety of operation.  相似文献   
993.
Abstract: To clarify the morphologic differences between hepatitis C virus (HCVI-negative autoimmune hepatitis (AIH) and HCV-positive AIH, peritoneoscopic findings were studied. Among twenty three patients with AIH according to the Japanese criteria (1992), 15 were HCV-negative and 8 were HCV-positive. The terms grooved depression, coarse depression, coarse elevation, coarse undulation, and round-shaped reddish marking (RM) were used in this study to evaluate the peritoneoscopic findings. Grooved depressions, coarse depressions, coarse elevations, coarse undulations and round-shaped RMs were all common findings (53%, 87%, 73%, 80%, and 80%, respectively) in HCV-negative AIH patients, but they were less common (13%, 25%, 13%, 13%, and 0%, respectively) in HCV-positive AIH patients. This study revealed that HCV-negative AIH patients had different peritoneoscopic findings from HCV-positive AIH patients. Thus HCV-negative AIH may be typical AIH, and HCV-positive AIH may essentially be a subset of type C chronic hepatitis.  相似文献   
994.
995.
Spread of the gastric cancer is multifarious according to its pathological and biophysiological characteristics. The therapeutic strategy was reviewed by the analysis of more than 8.000 cases of gastric cancer treated at Cancer Institute Hospital. Main type of recurrence in early stage cancer was, though seldom, the hematogenous metastasis to the liver. On the other hand, in the advanced cases, macroscopically localized, and histologically well differentiated tumor type easily adhered and invaded to the adjacent organs and structures, and infiltrating and undifferentiated tumor type tended to cause peritoneal dissemination. Lymph node spread was observed in any tumor type, but frequently observed in intermediate type. Invasion to the adjacent organs and limited lymphatic spread can be controlled by wide combined resection of adjacent organs, and extended lymphadenectomy. However, hematogenous metastasis and peritoneal dissemination are difficult to be controlled by surgical intervention. Thus, minor surgery can be directed for small early stage cancer under strict criteria, and wide and extended resection for localized type, and combination of surgery and adjuvant chemotherapy for intermediate and infiltrating tumor types advancing more than stage II.  相似文献   
996.
M Ono  H Ohta  M Ohhira  C Sekiya  M Namiki 《Tumour biology》1990,11(6):319-326
Des-gamma-carboxyprothrombin is an abnormal prothrombin which is drastically increased in the plasma of patients with hepatocellular carcinoma. To investigate the process of the abnormal prothrombin synthesis, the amount of prothrombin precursor was measured with an enzyme-linked immunosorbent assay using a specific antibody directed to human prothrombin; the vitamin-K-dependent gamma-carboxylation of prothrombin precursor was determined in human liver tissues. The tissue content of prothrombin precursor was increased in hepatoma tissues compared with noncancerous liver tissues, while the vitamin-K-dependent carboxylation of prothrombin precursor was markedly decreased in hepatoma tissues of the patients with increased plasma des-gamma-carboxyprothrombin. The present study indicates that in hepatocellular carcinoma an increase in prothrombin precursor concentration does not induce vitamin-K-dependent carboxylase activity, which is ordinarily observed in normal liver; probably an overproduction of prothrombin precursor with reduced gamma-carboxylation causes an increase in plasma des-gamma-carboxyprothrombin in patients with hepatocellular carcinoma.  相似文献   
997.
The spasmolytic and antispasmodic effects of Xylocaine in different concentrations were studied. Twenty-five Wistar rats were divided into five groups according to the concentrations of Xylocaine used (2 percent, 4 percent, 10 percent, 20 percent, and 40 percent). The diameters of rat femoral arteries were measured with vernier calipers under the microscope. Effects were evaluated by the percentage of the test arterial diameter compared with that of the control contralateral artery. Vasospasm of both femoral arteries was produced by administration of the fresh blood of other rats. After immersion in the blood for 10 min. Xylocaine was administered into the right femoral artery for 10 min to examine its spasmolytic effect. The effects of the concentrations shown by the percent diameter were 106 percent, 108 percent, 107 percent, 111 percent, and 106 percent, respectively. There was no significant statistical difference between each agent and its control. Thirty minutes after removal of the agent, 2 percent Xylocaine failed to maintain its spasmolytic effect, while 4 percent, 10 percent, 20 percent, and 40 percent Xylocaine did maintain it. Next, blood was again administered after vessel immersion in the agent to examine its antispasmodic effect. The effects of the concentrations were 100 percent, 114 percent, 124 percent, 152 percent, and 146 percent. There were statistically significant differences, except in the case of 2 percent Xylocaine. Twenty-percent Xylocaine demonstrated a superior antispasmodic effect. The duration of the spasmolytic effect and the antispasmodic effect were concentration-dependent, up to approximately 20 percent.  相似文献   
998.
Parthenogenesis is the process by which an oocyte develops into an embryo without being fertilized by a spermatozoon. Although such embryos lack the potential to develop to full term, they can be used to establish parthenogenetic embryonic stem (pES) cells for autologous cell therapy in females without needing to destroy normally competent embryos. Unfortunately, the capacity for further differentiation of these pES cells in vivo is very poor. In this study, we succeeded in improving the potential of pES cells using a nuclear transfer (NT) technique. The original pES cell nuclei were transferred into enucleated oocytes, and the resulting NT embryos were used to establish new NT-pES cell lines. We established 84 such lines successfully (78% from blastocysts, 12% from oocytes). All examined cell lines were positive for several ES cell markers and had a normal extent of karyotypes, except for one original pES cell line and its NT-pES cell derivatives, in which all nuclei were triploid. The DNA methylation status of the differentially methylated domain H19 and differentially methylated region IG did not change after NT. However, the in vivo and in vitro differentiation potentials of NT-pES cells were significantly (two to five times) better than the original pES cells, judged by the production of chimeric mice and by in vitro differentiation into neuronal and mesodermal cell lines. Thus, NT could be used to improve the potential of pES cells and may enhance that of otherwise poor-quality ES cells. It also offers a new tool for studying epigenetics.  相似文献   
999.
Using a time-lapse image acquired from a CCD camera, we developed a non-contact and non-invasive device, which could measure both the respiratory and pulse rate simultaneously. The time-lapse image of a part of the subject's skin was consecutively captured, and the changes in the average image brightness of the region of interest (ROI) were measured for 30s. The brightness data were processed by a series of operations of interpolation as follows a first-order derivative, a low pass filter of 2 Hz, and a sixth-order auto-regressive (AR) spectral analysis. Fourteen sound and healthy female subjects (22-27 years of age) participated in the experiments. Each subject was told to keep a relaxed seating posture with no physical restriction. At the same time, heart rate was measured by a pulse oximeter and respiratory rate was measured by a thermistor placed at the external naris. Using AR spectral analysis, two clear peaks could be detected at approximately 0.3 and 1.2 Hz. The peaks were thought to correspond to the respiratory rate and the heart rate. Correlation coefficients of 0.90 and 0.93 were obtained for the measurement of heart rate and respiratory rate, respectively.  相似文献   
1000.
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