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991.
The effect of treatment with interleukin-1 (IL-1), interferon- (IFN-), vincristine, and etoposide was evaluated on the secretion of transforming growth factor- (TGF-) and IL-10 and the expression of major histocompatibility complex (MHC) class I, intercellular adhesion molecule-1 (ICAM-1), and CD80 molecules by malignant glioma cells. Five malignant glioma cell lines were treated with IL-1, IFN-, and/or anticancer agents (vincristine and etoposide). Combined treatment with IL-1 and IFN- caused greater inhibition of TGF- secretion compared to treatment with IFN-, and almost the same levels of inhibition as treatment with vincristine and etoposide. The greatest inhibition of TGF- secretion was achieved by treatment with all agents. Low levels of IL-10 secretion were determined in two out of five malignant glioma cell lines. This IL-10 secretion was inhibited by treatment with IL-1, IFN-, vincristine, and/or etoposide. Treatment with both cytokines and anticancer agents increased the expression of MHC class I and ICAM-1 in all tumor cell lines. The mean increase of expression of MHC class I was 50% and that of ICAM-1 was 12-fold. No tumor cell lines expressed CD80 molecules on the cell surface, and no treatment caused CD80 expression. These results suggest that TGF- and IL-10 secretion by malignant glioma cells can be suppressed by treatment with a combination of IL-1, IFN-, vincristine, and etoposide, and the treatment up-regulates MHC class I and ICAM-1 expression on tumor cells. These results have implications for immunotherapy and chemotherapy in patients with malignant tumors.  相似文献   
992.
993.
The effects of intraventricular bombesin (BS) at doses of 0.1, 1.0, and 10.0 micrograms on thermoregulatory and cardiovascular functions were studied in conscious rats with a direct calorimeter at ambient temperatures (Ta) of 18, 23, and 28 degrees C. At two lower TaS, the central BS produced a profound decrease in colonic temperature (Tcol) with a reduction of the temperature difference between the interscapular brown adipose tissue (BAT) and the colon (TBAT-Tcol). Increases in nonevaporative and evaporative heat losses and mean arterial blood pressure (BP) were consistent following the central BS at any dose tested at any Ta. In the sinoaortic deafferentated rats, a 0.1 microgram of BS produced hypothermia with a significant decrease in (TBAT-Tcol) and heat production (M). Changes in Tcol, (TBAT-Tcol), and M in the denervated rats, however, were not different from those in the sham-operated rats. These results suggest that the central BS suppresses BAT thermogenesis and facilitates heat loss mechanisms. The baroreflex-mediated metabolic reduction is not the case in the BS-induced hypothermia in rats.  相似文献   
994.
While autoimmune hepatitis (AIH) and primary biliary cirrhosis (PBC) usually have distinct clinical manifestations, some patients present with features of both conditions. Using cDNA microarrays, we analyzed and compared gene expression profiles in 8 patients with AIH, 9 with PBC, 8 with chronic hepatitis C (CHC), 8 with non-alcoholic steatohepatitis (NASH) and 9 with normal livers. We subsequently applied this method to a tissue sample from a 61-year-old woman with overlapping features of both AIH and PBC. A 61-year-old woman was admitted to our hospital for evaluation of elevated serum alkaline phosphatase. A liver biopsy showed accumulation of mononuclear cells around the bile duct cells, a feature characteristic of chronic non-suppurative destructive cholangitis (CNSDC). Three years later, her serum alanine aminotransferase (ALT) level had increased, and a liver biopsy demonstrated evidence of a severe form of hepatitis. A cDNA microarray analysis of both biopsies identified the molecular events associated with her altered histology. The expression profile of this patient, which was originally different from that of the other PBC patients, changed to an AIH pattern. Our results suggest that this patient has characteristics of both AIH and PBC.  相似文献   
995.
Neutral endopeptidase 24.11 (NEP)/CD10 is a cell-surface peptidase that hydrolyzes various bioactive peptides. NEP is distributed in both normal and neoplastic cells and plays a functional role by modulating cellular responses to peptide substrates. Recently, NEP has been shown to be expressed in normal placental trophoblasts, suggesting its physiological role during pregnancy. In the present study, we investigated the expression of NEP in hyperplastic and anaplastic trophoblasts in gestational trophoblastic diseases (GTDs). Flow cytometric analysis demonstrated that NEP was expressed in all choriocarcinoma cell lines examined. The NEP enzyme activity in these cell lines correlated with cell-surface protein levels and was abolished by the NEP inhibitor phosphoramidon. On immunoblot analysis, NEP protein was detected in both hydatidiform mole and choriocarcinoma tissues as a double band of 95 and 100 kDa similar to that of the normal placental tissues. Immunohistochemical analysis revealed that NEP was present on syncytiotrophoblasts, while no or very faint NEP immunoreactivity was observed on cytotrophoblasts in the normal placenta. Similarly, NEP in hydatidiform mole and invasive mole was localized on the membrane of syncytiotrophoblasts, but not on hyperplastic cytotrophoblasts. In contrast, in choriocarcinoma, NEP was highly expressed not only on syncytiotrophoblastic cells but also on invading anaplastic cytotrophoblasts. In addition, NEP was also expressed on intermediate trophoblasts in placental site trophoblastic tumors. In summary, this is the first study demonstrating the expression of NEP/CD10 in GTDs. The differential localization of NEP among various trophoblastic tumors suggests that NEP may play a functional role in the regulation of trophoblast transformation and human chorionic gonadotropin secretion.  相似文献   
996.
This study examined the effect of local heating on the blood flow of the finger or forearm in male subjects in an environment of 35°C-40% (r.h.). One hand or forearm was immcrsed in a water bath the temperature of which (T w) was raised by 1°C every 10th min from 35° to 43°C, while the other hand or forearm was kept at a constantT w of 35°C. Blood-flow (BF) was measured by venous occlusion plethysmography, using temperature-compensated mercuryin-Silastic strain gauges. Finger BF in the heated hand was significantly lower than that in the control hand atT ws of 37°–41°C, mostly for the first few minutes of each heating period. Thereafter, finger BF in the heated hand gradually returned toward the previous values. AtT ws of 39°–40°C, liowever, finger BF in the heated hand remained lower than the control values for the entire period of heating. AtT ws of 42°–43°C, finger BF in the heated hand greatly increased after an initial transitory fall. In the forearm skin, however, no such vasoconstriction in response to local heating was observed. All this suggests that a rise in skin temperature to above the core temperature produces paradoxical vasoconstriction in the finger, which may be a mechanism to reduce heat gain through the hand heated locally at higher temperatures.  相似文献   
997.
The mechanisms of the hypothermic effect of angiotensin II (AII) injected into the lateral ventricle were investigated in unanesthetized rats at an ambient temperature of 18 degrees C. Mean blood pressure (BP), heart rate (HR), metabolic rate (M), colonic temperature (Tcol), and temperatures of the interscapular brown adipose tissue (TBAT), and the tail skin (Tsk) were continuously monitored. AII at a dose of 5 micrograms produced a sharp and marked elevation in BP accompanied by bradycardia, and a decrease of M and Tco1 in the sinoaortic baroreceptor intact rats. The difference between TBAT and Tcol decreased significantly, which suggests a suppression of nonshivering thermogenesis of the BAT. Tsk was not changed by the AII injection. After sinoaortic denervation, however, the decrease in Tcol and M with AII injection was significantly reduced despite a marked elevation in BP. In addition, intravenous arginine-vasopressin antagonist pretreatment suppressed the elevation in BP and the decrease in HR, Tcol, and M after AII injection. From these results, it is concluded that the hypothermia which occurred after AII injection into the lateral ventricle can be largely attributed to the baroreflexive suppression of M, and to some extent to the direct effect on the thermoregulatory center in rats.  相似文献   
998.
Objectives: Emerging evidence suggests that traditional diets and nutrition have a significant impact on brain development, and could contribute to the promotion of mental health and prevention of psychiatric disorders in children and adolescents. Moreover, deficits in parvalbumin (PV)-immunoreactive and/or GABAergic neurons are closely associated with various psychiatric disorders in children and adolescents. To investigate the possible neural mechanisms of diet involvement in mental health, we analyzed the effects of dried-bonito dashi (Japanese fish broth) (DBD) on PV-immunoreactive neurons and emotional behaviors in young mice.

Methods: Male mice after weaning were fed DBD for 60 days, and tested with a resident-intruder test for aggressiveness and a forced swimming test for depression-like symptoms. After the behavioral testing, PV-immunoreactive neurons in the brain were immunohistochemically analyzed.

Results: The results indicated that DBD intake decreased aggressiveness and depression-like symptoms, and increased the densities of PV-immunoreactive neurons in the medial prefrontal cortex (mPFC), amygdala, hippocampus, and superior colliculus. These behavioral changes were correlated with the densities of PV-immunoreactive neurons in the mPFC, amygdala, and hippocampus. However, subdiaphragmatic vagotomy did not affect the effects of DBD on emotional behaviors, although it nonspecifically decreased the densities of PV-immunoreactive neurons.

Discussion: The results suggest that DBD might modulate emotional behaviors by promoting PV-immunoreactive and/or GABAergic neuronal activity through parallel routes. The present results highlight a new mechanism for diet involvement in brain functions, and suggest that DBD might have therapeutic potential for the promotion of mental health.  相似文献   

999.
Summary Two fluoro analogs of 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], 24a-homo-24,24-difluoro-1,25-dihydroxyvitamin D3 [24aF2-homo-1,25(OH)2D3], and 26,27-dimethyl-24,24-difluoro-1,25-dihydroxyvitamin D3 [24F2-1,25(OH)2(Me)2D3] were examined for calcium (Ca)-regulating activity. The objective of the present study was to determine whether or not fluoro substitution at 24-position would alter activities of the original compounds, that is, 26,27-dimethyl 1, 25-dihydroxyvitamin. D3[1,25(OH)2 (Me)2D3] and 24-homo-1,25-dihydroxyvitaminD3[24homo-1,25(OH)2D3], respectively. The relative activities of 24aF2-homo-1,25(OH)2D3, 24F2-1,25(OH)2(Me)2D3, and 1,25(OH)2D3 in competing with 1,25(OH)2D3 for binding to chick intestinal cytosol receptor were 0.28:0.5:1.0. The relative potencies of the same series of compounds in competition for the vitamin D-deficient rat serum binding sites were 0.04:0.15:1. Bone-resorbing activities of two fluoro analogs in cultures of neonatal mouse parietal bones were more potent than that of 1,25(OH)2D3. Similar results were recognized in stimulating activities of osteoclast-like cell formation. Responses of two fluoro analogs to intestinal Ca absorption were similar to that of 1,25(OH)2D3. The potencies of 1,25(OH)2D3. and its fluoro analogs in bone Ca mobilization were the highest with 1,25(OH)2D3. followed by 24F2 1,25(OH)2(Me)2D3 and 24aF2-homo-1,25(OH)2D3, in that order. From these results and the data of Paulson et al. [24], fluoro substitution in 24-position of 1,25(OH)2D3. apparently does not alter their activities, hence, the fluoro substitution at 24-position of 1,25(OH)2D3. and the elongation of side chain of 1,25(OH)2D3. may not intensify Ca-regulating activity.  相似文献   
1000.
A new tumor marker was tested (serum erbB-2 protein) in 128 patients with gastric cancer and 110 patients with benign gastric diseases, and the results were correlated with erbB-2 tissue status and clinicopathological parameters. Abnormal level of erbB-2 protein was found in 15/128 (12%) of gastric cancer patients and in 2/110 (2%) of benign gastric diseases. Elevated erbB-2 levels did not correlate with age, sex, tumor size, macroscopic type, histologic type, serosal invasion, nodal status, or clinical stage. In all the 15 patients except one case, with abnormally high level of serum erbB-2, erbB-2 immunoreactivity was confirmed in the primary tumors by immunohistochemical staining. The percentage of positive serum levels of alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA) and CA 19-9 were 6%, 16% and 20%, respectively. However, there was no relation between serum erbB-2 level and CA 19-9, CEA or AFP level. If the CA 19-9 was assayed in combination with erbB-2, the overall sensitivity was 30%. In addition, the combination of the three markers of erbB-2, CEA and CA 19-9 gave a sensitivity of 41%. Patients with abnormal erbB-2 serum level run poorer prognoses than did the patients with normal erbB-2 serum level. We conclude that erbB-2 protein is an attractive tumor marker, and a powerful prognostic indicator of gastric cancer patients.  相似文献   
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