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11.
A total of 48 water samples and 24 sediment samples were collected at four sampling stations along the wetland during four seasons from 2009 to 2010 and analyzed by gas chromatograph–electron capture detector (GC–ECD). In water the total concentration of OCPs was 0.33, 0.01, 0.1 and 0.07 mg/L in summer, autumn, winter and spring, respectively. The most frequent OCP compounds detected were endrin and chlordane (0.08 and 0.07 mg/L), heaxachlorobenzene and chlordane (0.06, 0.02 mg/L), and chlordane (0.07 mg/L) in summer, winter and spring, respectively. The maximum concentration of ΣOCPs was found in samples collected from station 1 in summer (0.26 mg/L). In sediments the total concentrations of OCPs were 15.84 and 2.62 mg/g-dry weight (dw) in summer and winter, respectively. Chlordane was the most frequently found OCP compound, followed by lindane, 9.92 and 2.47 mg/g-dry weight (dw), respectively, in summer. While, lindane (2.52 mg/g-dw) and endosulfan I (0.1 mg/g-dw) were the highest OCP compounds detected in winter. The results obtained in this study show that there still exist a variety of organochlorine pesticide residues in the water and sediments from the Amir-kalaye wetland in Iran.  相似文献   
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Although there is increasing evidence that blood‐derived macrophages support tumor progression, it is still unclear whether specialized resident macrophages, such as brain microglia, also play a prominent role in metastasis formation. Here, we show that microglia enhance invasion and colonization of brain tissue by breast cancer cells, serving both as active transporters and guiding rails. This is antagonized by inactivation of microglia as well as by the Wnt inhibitor Dickkopf‐2. Proinvasive microglia demonstrate altered morphology, but neither upregulation of M2‐like cytokines nor differential gene expression. Bacterial lipopolysacharide shifts tumor‐educated microglia into a classical M1 phenotype, reduces their proinvasive function, and unmasks inflammatory and Wnt signaling as the most strongly regulated pathways. Histological findings in human brain metastases underline the significance of these results. In conclusion, microglia are critical for the successful colonization of the brain by epithelial cancer cells, suggesting inhibition of proinvasive microglia as a promising antimetastatic strategy. © 2010 Wiley‐Liss, Inc.  相似文献   
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In the mammalian pineal gland, the rhythm in melatonin biosynthesis depends on the norepinephrine (NE)-driven regulation of arylalkylamine N-acetyltransferase (AANAT), the penultimate enzyme of melatonin biosynthesis. A recent study showed that phytocannabinoids like tetrahydrocannabinol reduce AANAT activity and attenuate NE-induced melatonin biosynthesis in rat pineal glands, raising the possibility that an endocannabinoid system is present in the pineal gland. To test this hypothesis, we analyzed cannabinoid (CB) receptors and specific enzymes for endocannabinoid biosynthesis or catabolism in rat pineal glands and cultured pinealocytes. Immunohistochemical and immunoblot analyses revealed the presence of CB1 and CB2 receptor proteins, of N-acyl phosphatidyl ethanolamine hydrolyzing phospholipase D (NAPE-PLD), an enzyme catalyzing endocannabinoid biosynthesis and of fatty acid amide hydrolase (FAAH), an endocannabinoid catabolizing enzyme, in pinealocytes, and in pineal sympathetic nerve fibers identified by double immunofluorescence with an antibody against tyrosine hydroxylase. The immunosignals for the CB2 receptor, NAPE-PLD, and FAAH found in pinealocytes did not vary under a 12 hr light:12 hr dark cycle. The CB1 receptor immunoreaction in pinealocytes was significantly reduced at the end of the light phase [zeitgeber time (ZT) 12]. The immunosignal for NAPE-PLD found in pineal sympathetic nerve fibers was reduced in the middle of the dark phase (ZT 18). Stimulation of cultured pinealocytes with NE affected neither the subcellular distribution nor the intensity of the immunosignals for the investigated CB receptors and enzymes. In summary, the pineal gland comprises indispensable compounds of the endocannabinoid system indicating that endocannabinoids may be involved in the control of pineal physiology.  相似文献   
18.

Background/Aim:

Thrombocytosis is found to be associated with unfavorable prognosis in esophageal carcinoma. Platelets produce thymidine phosphorylase which is a platelet-derived endothelial cell growth factor with angiogenic activity. Increased platelet count may be translated into enhanced tumor growth. We examined the relation between platelet count and several prognostic variables in patients with esophageal cancer.

Patients and Methods:

Three hundred and eighty-one cases with esophageal cancer that underwent esophagectomy in a referral cancer institute during a 5-year period were studied retrospectively. The relation between preoperative platelet count and patient age, gender, site of tumor, presence of multiple cancers and clinicopathological characteristics including histological type, tumor size, depth of penetration (T), lymph node involvement (N), distant metastasis (M), degree of differentiation, presence of vascular, lymphatic and perineural invasion was examined.

Results:

Squamous cell carcinoma (SCC) constituted 93% and adenocarcinoma 7% of cases. Most of patients were in stage III, followed by stage II. The mean platelet count was 245±76 (× 109 /L). There was no statistically significant correlation between platelet counts with prognostic factors except a weak linear correlation between platelet count and and tumor size (P= 0.03, Pearson correlation coefficient: 0.16). Patients with adenocarcinoma had a higher platelet count than those with SCC (P= 0.003).

Conclusion:

Platelet count does not correlate with prognostic factors in esophageal cancer. However, it is significantly different between SCC and adenocarcinoma of esophagus.  相似文献   
19.

Background

Wilson disease (WD) is an autosomal recessive disorder. The WD gene, ATP7B, encodes a copper-transporting ATPase involved in the transport of copper into the plasma protein ceruloplasmin and in excretion of copper from the liver. ATP7B mutations cause copper to accumulate in the liver and brain.

Objectives

We examined the ATP7B mutation spectrum in Wilson disease patients in Iran.

Patients and Methods

Genomic DNA was extracted from patients with Wilson disease. The entire coding region of the ATP7B gene was amplified using PCR and analyzed using direct sequencing.

Results

We identified five novel mutations in 5 Iranian patients with Wilson disease. The first was a transversion, c.2363C > T, which led to an amino acid change from threonine to isoleucine. The second mutation was a deletion, c.2532delA (Val845Ser), which occurred in exon 10. The third mutation was a transition mutation, c.2311C > G (Leu770Leu), which occurred in the TM4 domain of the ATP7B protein. The fourth mutation was a transversion, (c.3061G > A) (Lys1020Lys), in exon 14. Lastly, we identified a transversion, c.3206C > A (His1069Asn) in exon 14 which led to a change in function of the ATP loop domain of the ATP7B protein. The H1069Q mutation was identified as the most common mutation in our study population.

Conclusions

Based on our findings, the H1069Q may be a biomarker that can be used in a rapid detection assay for diagnosing WD patients  相似文献   
20.
The percentage of blasts in the bone marrow aspirates at day 7 or 14 of induction therapy in pediatric ALL patients is an indicator of rapid early response and an independent prognostic factor for long term outcome. Discrepancies between the percentages of blasts in bone marrow aspirates compared to biopsies have been reported. In a retrospective study on 44 consecutive patients diagnosed with ALL between 1998 and 2001, important differences were observed in the percentage of blasts between bone marrow aspirates and biopsies at days 7 and 14 of induction therapy.  相似文献   
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