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51.
Pseudomonas sp. (L1), P. diminuta(L2) were among eight bacterial strains isolated from vegetable grease and oil-contaminated industrial wastewater, four of which only were found to have the ability to degrade oil and grease. They were identified and investigated for oil and grease degradation either individually or in combinations in previous unpublished work by the authors. Since the combination M1 (Pseudomonas sp. andP. diminuta) produced the highest degradative activity, it was used in the present study in a biofilm sand filter system for vegetable oil and grease removal. This system was tested either as one unit or two units in sequence where different flow rates (30, 50, 100 ml/h) were applied compared to a control unit(s). Results showed that both biofilm systems reduced oily wastewater, even in cases of high degree of pollution (fat, oil & grease (FOG), 7535 ppm; biochemical oxygen demand (BOD5), 525 ppm; chemical oxygen demand (COD), 1660 ppm). Results also showed a removal of FOG with efficiency at 100%; BOD5 at 95.9% and COD at 96%, at 50 ml/h flow rate using one unit of biofilm system. On using two units in sequence, a complete removal of FOG, BOD5 and COD with efficiency 100%, at flow rate 100 ml/h was achieved. In conclusion, the previous biofilm results indicated the efficiency of such a system in treating oily polluted wastewater (vegetable oil origin) on the basis of bacterial isolates being used, the optimum flow rate, and the number of biofilm units used in sequence to obtain the highest removal capacity of such a system. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
52.

Background

The ankle brachial index (ABI) is a well-established tool for screening and diagnosis of peripheral arterial disease (PAD). In this study we assessed the validity of ABI determination using a pocket Doppler device compared with automatic vascular laboratory measurement in patients suspected of PAD.

Methods

Consecutive patients with symptoms of PAD referred for ABI measurement between December 2006 and August 2007 were included. Resting ABI was determined with a pocket Doppler, followed by ABI measurement with automatic vascular laboratory equipment, performed by an experienced vascular technician. The leg with the lowest ABI was used for analysis.

Results

From 99 patients the mean resting ABI was 0.80 measured with the pocket Doppler and 0.85 measured with vascular laboratory equipment. A Bland-Altman plot demonstrated great correspondence between the two methods. The mean difference between the two methods was 0.05 (P < .001). Multivariate linear regression analysis showed no dependency of the difference on either the average measured ABI or affected or unaffected leg.

Conclusion

Since the small, albeit statistically significant, difference between the two methods is not clinically relevant, our study demonstrates that ABI measurements with pocket Doppler and vascular laboratory equipment yield comparable results and can replace each other. Results support the use of the pocket Doppler for screening of PAD, allowing initiation of cardiovascular risk factor management in primary care, provided that the equipment operator is experienced.  相似文献   
53.
Nawal El Ansari 《Andrologie》2008,18(2):127-130
Kallmann syndrome (KS) is a rare, heterogeneous disorder consisting of congenital hypogonadotropic hypogonadism, associated with anosmia (or hyposmia) and other clinical manifestations such as mirror movements, and renal, urological and neurosensory disorders. The presence of anosmia with micropenis in boys is suggestive of the diagnostic of KS. In KS, the GnRH neurons do not migrate correctly from the olfactory placode to the hypothalamus during development and olfactory bulbs also fail to form, leading to anosmia. Mutations in KAL1 which encodes Anosmin-1, are responsible for the X-linked form of KS. Anosmin-1 is normally expressed in the brain, facial mesenchyme, mesonephros and metanephros. It is required to promote migration of GnRH neurons into the hypothalamus. It also allows migration of olfactory neurons from the olfactory bulbs to the hypothalamus. The loss of function mutations in FGFR1 “fibroblast growth factor” were identified in 2003 as a cause of autosomal forms of this disease. An additional autosomal cause of Kallmann syndrome was recently identified by a mutation in the prokineticin receptor-2 gene (PROKR2) (KAL-3) and its ligand prokineticin 2 (PROK2) (KAL-4). Mutations in these genes induce various degrees of olfactory and reproductive dysfunction, but not the other symptoms seen in KAL-1 and KAL-2 forms of KS. Neuropilin2, which has an important role in migration of GnRH neurons, is a recent candidate gene for KS. The authors describe the genetic features and recent findings of KS, necessary to understand this disease.  相似文献   
54.
Afzal, the common smokeless tobacco product (STP) in Oman, is believed to contain toxins that may impair the function of some organs such as liver and kidney. An aqueous extract from Afzal was added to drinking water to be administrated orally to Wistar albino rats (n = 72) young and adult from both genders weighing between 60–80 g and 150–240 g respectively for 8 weeks. Animals were divided into three groups: control (distilled water instead of Afzal extract), low-dose (3 mg nicotine/kg body weight/day) and high-dose (6 mg nicotine/kg body weight/day). The animals were euthanized and their blood, liver and kidney were collected for biochemical and histopathological investigations. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were assayed for the liver function, while blood urea nitrogen (BUN) and creatinine (CRT) were assayed for the kidney function. The results showed a significant increase in the ALT, AST, BUN and CRT levels (P < 0.05) in both Afzal-treated groups (low and high doses) compared with the control. Histopathological findings revealed the initial but seem to be serious degenerative alterations of periportal fibrosis in liver and edematous and calcified changes in renal glomerulus among Afzal-treated groups. Additionally, the weight gain of the Afzal-treated groups was lower than the control group. Our findings show that the exposure of Wistar rats to the Afzal extract has the potentials of causing decreased weight gain and dose-dependent functional and structural damage to the biochemical and histological profiles of liver and kidney as well as serious biochemical effects.  相似文献   
55.
Overexpression of nuclear factor (NF-κB) or activation of Smad3 by transforming growth factor β (TGF-β1) induced by oncogenes results in overexpression of fibrotic processes and hence cell death. The objective of this study is to examine whether Silymarin (Sil) alone or in combination with Vitamin E (Vit E) and/or Curcumin (Cur) plays a modulatory role against the overexpression of NF-κB, and TGF-β that induced in response to carbon tetrachloride (CCl4) administration. The present work revealed that CCl4 induced elevation of in serum alanine aminotransferase (ALT), Apoptosis regulator (Bax), Smad3, TGF-β, and NF-kB hepatic mRNA expression (using Real-time PCR), administration of Sil alone downregulated these expressions. Treatment with Vit E acid and/ or Cur along with Sil produced best results in this concern. B-cell lymphoma 2 (Bcl-2) expressions were downregulated by CCl4; whereas concurrent treatment of Vit E and/or Cur along with Sil increased its expression. On conclusion, the use of Vit E and/or Cur could potentiate the antiapoptotic action of Sil.  相似文献   
56.
57.
Summary In steroid target tissues, the presence of the corresponding hormone receptors is indicative of hormone dependence. In an attempt to assess the possible role of steroid hormones in the mechanism of growth and/or differentiation of cancerous pancreatic duct cells, the expression of estrogen receptor (ERα) was evaluated in human cancerous pancreatic duct cells (Capan-1) maintained in culture. These cells were selected as they acquire progressively a high degree of differentiation during growth in culture. In the present study, we showed that Capan-1 cells during growth in steroid-free medium associate spontaneously, become polarized, and form duct-like structures, features that are indicative of a high degree of differentiation. Capan-1 cells were also found to express ERα and progesterone receptor (PR). Immunoenzymatic assay showed maximal expression of ERα (236 ± 55 fmol/mg protein) on the first day of the exponential growth phase, followed by a marked fall in expression (76.3%). At the onset of the stationary phase (Day 5), ERα levels were below 10 fmol/mg protein, becoming undetectable by Day 7. A similar time course was observed for PR: 18 ± 0.9 fmol/mg protein at the onset of the exponential growth phase and no expression during the stationary phase. Addition of estradiol to 1-d-old cultures resulted in a twofold increase in PR expression, suggesting an induction of PR expression by estrogen. Immunocytochemical analysis with anti-ERα-1D5 antibodies showed nuclear and cytoplasmic localization of ERα in Capan-1 cells in the first 24 h of culture followed by a progressive disappearance thereafter. We also showed that cellular multiplication was increased by estradiol and progesterone during the exponential growth phase, pointing to the involvement of steroid hormones in the proliferation of nonpolarized Capan-1 cells. These results indicate that the expression of ERα is linked to the state of differentiation of the cells and make Capan-1 cells a model of choice to study ER regulation in nontarget tissues.  相似文献   
58.
Regular counts of the eggs ofCulex quinquefasciatus Say were recorded during the period April 1979 – March 1981. The results indicate that the lowest numbers of eggs laid were during summer months (May and June) and the highest ones were during winter months (November and January). The decline of numbers during summer was mainly due to small size of adults (0.57 mg, average wt of female). Populations flourished during the rainy season (July – October) and reached their peak in August. Bigger batches of eggs were then obtained. In winter prolongation of larval life gave rise to large-sized adults and hence bigger batches of eggs.  相似文献   
59.
The range of environmental temperatures that allow of survival would appear to be greater forAnopheles arabiensis than forCulex quinquefasciatus. Nevertheless the latter is the more common species in the Khartoum (Sudan) area.This relative abundance is suggested to be attributed largely to the success ofCulex quinquefasciatus in exploiting a wide range of breeding sites, even those which are obviously contaminated in various ways.  相似文献   
60.
22 indole alkaloids were isolated from the stem bark of Nigerian Rauwolfia vomitoria and 20 characterized. The alkaloids comprised E-seco heteroyohimbine, sarpagan, dihydroindole, yohimbine and heteroyohimbine types. The biosynthetic relationship of the alkaloids is discussed.  相似文献   
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