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991.
992.
Water quality and the distribution of some heavy metals in three different organs of Lepomis gibbosus from the Cine Stream were studied. Also, histopathological changes in gill, liver, and muscle tissue were examined at light microscopical level. Micronucleus (MN) formation in fish erytrocytes, as an indicator of chromosomal damage, has been increasingly used to detect the genotoxic potential of environmental contaminants. The frequency of MN was examined from samples of fish from the Cine Stream and a control group. MN frequency was higher in fish samples caught from the Cine Stream than that in the control group. The chemicals ammonia, nitrite, nitrate, orthophosphate, and sulphate were determined as parameters that possibly affect the gill, liver, and muscle morphology. Zn was the most accumulated metal in tissues as well as in water. Maximum metal accumulation occurred in both liver and gills. For histopathological examinations, samples of gills, liver, and muscle tissues of L. gibbosus were studied by using light microscopy. In this study, a significant decrease in mean length of primary and secondary lamellae were observed. Moreover, cellular proliferation developed with secondary lamellae fusion, ballooning degenerations or club deformation of secondary lamellae, as well as distribution of necrotic, hyperplastic and clavate secondary lamellae. In the liver, altered staining, swollen and ruptured parenchymal cells, loss of cord structure, reduce of glycogen in hepatocytes, and vacuolar structure filled with cellular debris and many dark particles were seen. In muscle tissue, focal necrosis, cellular dissolution, and a decline or loss of striation in muscle fibres were found.  相似文献   
993.
The vascular effect of salvigenin (6-hydroxyapigenin 6,7,4' -trimethyl ether), a natural flavone, was investigated in comparison with another flavone, 6-hydroxyluteolin 6,7,3',4' -tetramethyl ether in rat aortic rings. Cumulative addition of their increasing concentrations (10(-9)-10(-4)M) produced graded relaxations on rings precontracted with noradrenaline (10(-6) M) and KCl (40 mM). The maximal relaxations induced by flavones were similar, however, based on their pEC50 values salvigenin displayed a higher potency than 6-hydroxyluteolin 6,7,3',4'-tetramethyl ether. Endothelium removal markedly reduced the relaxations to salvigenin while the responses to 6-hydroxyluteolin 6,7,3',4'-tetramethyl ether were partially affected. In addition, a significant decrease was observed in maximal responsiveness and sensitivity to flavones in the presence of L-NOARG, a NO synthase inhibitor. The cyclooxygenase inhibitor indomethacin significantly inhibited the relaxations to salvigenin, but not altered the responses to 6-hydroxyluteolin 6,7,3',4'-tetramethyl ether. Our results provide evidence that salvigenin is an effective flavone in causing vasorelaxation which appears to be mediated by endothelium derived NO and prostacyclin. Whereas, the other flavone, 6-hydroxyluteolin 6,7,3',4'-tetramethyl ether induced relaxant responses are partially endothelium, presumably NO mediated.  相似文献   
994.
We report a case of a premenopausal woman with severe constipation causing intermittent obstruction. Colonoscopy revealed a tight rectal stricture; however, mucosal biopsies were normal. Exploratory surgery revealed an intense fibrotic reaction involving the rectum and uterus, necessitating a simultaneous low anterior resection and hysterectomy. Pathology established a diagnosis of endometriosis. Preoperative diagnosis of rectal endometriosis can be difficult to establish. Endometrial deposits do not invade the mucosa; therefore, colonoscopy with biopsies are frequently non-diagnostic. Surgery may be the only definitive way to obtain a certain diagnosis. In cases involving rectal strictures of unknown etiology in premenopausal women, rectal endometriosis must be included in the differential diagnosis.  相似文献   
995.
996.
The aim of this study was to investigate the possible protective effects of aqueous garlic extract (AGE) against naphthalene-induced oxidative changes in liver, kidney, lung and brain of mice. Balb/c mice (25-30 g) of either sex were divided into five groups each comprising 10 animals. Mice received for 30 days: 0.9% NaCl, i.p. (control); corn oil, i.p; AGE in a dose of 125 mg kg-1, i.p.; naphthalene in a dose of 100 mg kg-1, i.p. (dissolved in corn oil); and AGE (in a dose of 125 mg kg-1, i.p.) plus naphthalene (in a dose of 100 mg kg-1, i.p.). After decapitation, liver, kidney, lung and brain tissues were excised. Malondialdehyde (MDA) and glutathione (GSH) levels and myeloperoxidase activity (MPO) were determined in the tissues, while oxidant-induced tissue fibrosis was determined by collagen content. Tissues were also examined microscopically. Serum aspartate aminotransferase, alanine aminotransferase levels and blood urea nitrogen and creatinine concentrations were measured for the evaluation of hepatic and renal function, respectively. MDA and GSH levels were also assayed in serum samples. In the naphthalene-treated group, GSH levels decreased significantly, while MDA levels, MPO activity and collagen content increased in the tissues (P<0.01-0.001), suggesting oxidative organ damage, which was also verified histologically. In the AGE-treated naphthalene group, all of these oxidant responses were reversed significantly (P<0.05-0.01). Hepatic and renal function test parameters, which increased significantly (P<0.001) following naphthalene administration, decreased (P<0.05-0.001) after AGE treatment. The results demonstrate the role of oxidative mechanisms in naphthalene-induced tissue damage. The antioxidant properties of AGE ameliorated oxidative organ injury due to naphthalene toxicity.  相似文献   
997.
Protein-based therapeutic agents intended for bone diseases should ideally exhibit a high affinity to bone tissue, so that their systemic administration will result in specific delivery to bone with minimal distribution to extra-skeletal sites. This was shown possible in the authors' lab by modifying a desired protein with bisphosphonates (BPs) that exhibit an exceptionally high affinity to the bone-mineral hydroxyapatite. In this review, we explore the potential applications of that concept by summarizing the bone diseases and candidate proteins that will benefit from the proposed bone delivery approach. A selective synopsis of BP synthesis is presented to highlight the synthesis of functional BPs suitable for covalent attachment to proteins. Finally, we present a summary of recent research results from the authors' laboratory emphasizing factors influencing bone affinity of the conjugates. We conclude with future research avenues that are considered critical for clinical entry of the BP-targeted therapeutic agents.  相似文献   
998.
BACKGROUND AND AIMS: Postprandial increase of 5-hydroxytryptamine (5-HT) has been implicated in irritable bowel syndrome (IBS). There is evidence that nitric oxide (NO) may act as a mediator of 5-HT-evoked secretions in the colon. Our aim is to investigate the role of urinary 5-hydroxyindole acetic acid (5-HIAA) and plasma NO levels (with diarrhoea) in IBS patients. Methods: Nineteen (with constipation) IBS patients (group 1), 22 IBS patients (group 2) and 18 healthy controls (group 3) were included in the study. The diagnosis of IBS was made according to the Rome I Criteria. The urine was collected for determination of 5-HIAA and venous blood was collected from each subject for the measurement of plasma NO levels. RESULTS: The levels of urinary 5-HIAA mmol/day and plasma NO mmol/l of group 1 (22.4 +/- 2.2 and 29.4 +/- 2 respectively) were significantly higher than group 3 (14.2 +/- 2.3 and 21.3 +/- 2.1 respectively) (p = 0.036 and p = 0.019 respectively). The NO level of group 1 was also significantly higher than group 2 (21.8 +/- 1.9) (p = 0.021). The 5-HIAA level of group 1 was higher than group 2 (15.2 +/- 2.1) and the difference was marginally significant (p = 0.055). There was no difference between group 2 and group 3 with respect to 5-HIAA and NO levels. CONCLUSIONS: The results of this preliminary study lend support to the involvement of 5-HT in some symptomatology of diarrhoea predominant IBS. Furthermore, NO may be one of the effector mediators of the 5-HT-induced symptoms in these patients.  相似文献   
999.
In this study, a synthetic pyrethroid insecticide, lambda-cyhalothrin (LCT), was administered to adult female albino rats (Wistar rats) by gavage dose of 6.12, 3.06, 0.8 mg/kg b.w. repeated for 13 days at 48 h intervals. The cytotoxic and genotoxic effects of LCT were investigated in bone marrow cells, using the structural chromosomal aberration (SCA) and micronucleus (MN) test systems. Mitomycin C (MMC) was also used as positive control (2mg/kg b.w.). All the doses of LCT increased the number of SCAs and the frequency of micronucleated erythrocytes, with respect to the control group. Only the highest dose of LCT significantly increased the MN frequency compared with control (P < 0.01). It was also observed that LCT caused a significant decrease in the number of polychromatic erythrocytes compared with controls (p < 0.001). These observations indicate the in vivo suspectibility of mammals to the genetic toxicity and cytotoxicity potential of LCT.  相似文献   
1000.
Mediastinal lymph node enlargement in operable non-small cell lung cancer is of clinical importance since it indicates the high possibility of nodal metastasis. The coincidence of tuberculosis and lung cancer is detected by the mediastinal lymph node staging of lung cancer patients. In our study, we retrospectively re-evaluated the records of patients who had been hospitalized with the diagnosis of lung cancer for the past 10 years. The mean age was 58 +/- 10 years (ranging from 39 to 72). A tuberculous lymphadenitis was detected in 16 of the 315 (5.1%) patients in one and/or multiple stations by either mediastinoscopy or thoracotomy. Inferior paratracheal lymph nodes (4R-4L) were the most frequently affected. None of the patients had a history of primary tuberculosis infection. The cell type was squamous cell carcinoma in ten patients (62.5%) and adenocarcinoma in six patients (37.5%). The tumour was located in the right lung in nine patients (56.2%). The most frequently involved site was the right upper lobe (n = 13, 81.2%). N2 disease was detected in six patients (37.5%). Our study showed that 5.1% of lung patients had tuberculous lymphadenitis coincidentally. The diagnosis and treatment of this latent disease could be considered as important, especially in lung cancer patients who would potentially receive radiotherapy or chemotherapy which alters the immune system. However, the real value of this finding needs further study.  相似文献   
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