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81.
Many physicians are reluctant to lower blood pressure to recommended levels in elderly hypertensive patients because of concern about producing cerebral hypoperfusion. Because hypertension is associated with potentially reversible structural and functional alterations in the cerebral circulation that may improve with treatment, we investigated whether long-term pharmacological reduction of systolic blood pressure will improve, rather than worsen, cerebral blood flow and its regulation. Three groups of elderly subjects 65 years of age or older were studied prospectively: normotensive subjects (N=19), treated hypertensive subjects with systolic pressure <140 mm Hg (N=18), and uncontrolled hypertensive subjects with systolic pressure >160 mm Hg at entry into the study (N=14). We measured beat-to-beat blood flow velocity in the middle cerebral artery (transcranial Doppler ultrasonography), finger arterial pressure (photoplethysmography), and pulsatile distensibility of the carotid artery (duplex Doppler ultrasonography) at baseline and after 6 months of observation or antihypertensive therapy. After baseline hemodynamic measurements, uncontrolled hypertensive subjects underwent aggressive treatment with lisinopril with or without hydroclorothiazide or, if not tolerated, nifedipine or an angiotensin receptor blocker to bring their systolic pressure <140 mm Hg for 6 months. The other 2 groups were observed for 6 months. After 6 months of successful treatment, uncontrolled hypertensive subjects had significant increases in cerebral blood flow velocity and carotid distensibility that was not seen in the other groups. Treatment reduced cerebrovascular resistance and did not impair cerebral autoregulation. Therefore, judicious long-term treatment of systolic hypertension in otherwise healthy elderly subjects does not cause cerebral hypoperfusion.  相似文献   
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Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Over the years, grilling and smoking as food preparation techniques have been found to introduce polycyclic...  相似文献   
83.
A subchronic toxicity study was carried out to assess hepatic and renal functions of rats during oral exposure to glyphosate with zinc for the period of 8 weeks. Forty-eight Wistar rats used for the study were randomized into six groups of eight Wistar rats each, and each group had equal number of male and female Wistar rats. The Wistar rats administered with distilled water at 2 ml/kg body weight served as the control group (DW); others were administered with zinc at 50 mg/kg body weight (Z) group, glyphosate at 375 mg/kg body weight (G) group, a combination of zinc and glyphosate at 50 and 375 mg/kg body weight, respectively (Z?+?G), group, glyphosate at 14.4 mg/kg body weight (GC) group, and a combination of zinc and glyphosate at 50 and 14.4 mg/kg body weight, respectively (Z?+?GC), group. At the end of the study, blood samples were collected from each rats; from which, sera samples were obtained and assayed for total protein, albumin, alanine and aspartate aminotransferases, alkaline phosphatase, Na+, K+, Cl?, \( \mathrm{HCO}_3^{-} \) , Ca2+, \( \mathrm{PO}_4^{-} \) , urea and creatinine using autoanalyzer, and globulin was calculated. The albumin concentration was significantly high (p?<?0.05) in GC group compared to DW group, and this change was ameliorated following supplementation with zinc. The total protein and globulin concentrations did not differ significantly between the groups (p?>?0.05), and the relative changes were ameliorated by supplementation with zinc. The alkaline phosphatase activity was relatively low in GC group; however, supplementation with zinc in Z?+?GC group made it to be significantly high (p?<?0.05) compared to GC group. The alanine and aspartate aminotransferases in G and GC groups were relatively high compared to DW group, which were ameliorated by supplementation with zinc. The relatively low Ca2+ concentration in G and GC groups compared to DW were ameliorated in Z?+?G group, and it was significantly high in Z?+?GC group at p?<?0.01 compared to DW, p?<?0.001 compared to G and GC groups and p?<?0.05 compared to Z?+?G group. There were only slight changes in the electrolytes concentrations (Na+, K+, Cl?, \( \mathrm{HCO}_3^{-} \) and \( \mathrm{PO}_4^{-} \) ), which were differentially ameliorated by zinc supplementation. The reasons for the various changes recorded were discussed. It was concluded that subchronic oral exposure to glyphosate caused both hepatic and renal functions toxicity in rats, which were ameliorated by zinc supplementation.  相似文献   
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One of the components of the current WHO strategy to fight malaria is early recognition and prompt and appropriate treatment. We investigated determinants of delay in seeking early and appropriate malaria treatment for children (0–5 years) in Ohaji/Egbema, South Eastern Nigeria. Data was collected using structured pre-tested questionnaires elicited in the local language (Igbo) to 738 consenting mothers within the child bearing age (15–49 years). About twenty-two percent (22 %) of the respondents sought treatment within 24 h for their children with malaria and were excluded from further investigation. More than half of the remaining respondents (51.5 %) delayed in seeking treatment because they had to watch their children for some days, while 21.4 % were due to financial difficulties. The age, parity, marital status/type of marriage and educational attainment of the mothers including family social-economic status were found to be statistically related to delay in seeking appropriate treatment (P < 0.05). Wrong first line treatment choices by the respondents also contributed to this delay. These results underscore the need to improve awareness of mothers and caregivers on the need and ways of seeking early, appropriate and effective treatment for their children who have malaria. This is very important if the WHO strategy of early recognition, prompt and appropriate treatment is to be effective so as to sufficiently reduce mortality and morbidity due to malaria among children in endemic rural areas. It will also aid in the proper management and treatment of other childhood febrile illnesses.  相似文献   
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Plasmablastic lymphoma (PBL) is an uncommon, clinically aggressive, Epstein-Barr virus-driven B-cell lymphoma that was initially described in tumors of relatively young human immunodeficiency virus-positive men. Subsequent to initial reports, the clinical and pathological spectrum of this disease has been expanded such that, now, PBL is recognized to be a heterogeneous disease entity. Plasmablastic lymphoma has been seen in clinical settings outside those initially reported and has been shown to demonstrate a variety of morphologic patterns. We describe a case of extraoral PBL in an human immunodeficiency virus-infected patient with a computed tomography-identified heterogeneously enhancing mass in the stomach. Histologically, a prominent intravascular component was identified. Fluorescent in situ hybridization analysis for MYC/IGH (immunoglobulin heavy chain) rearrangement t(8;14) identified fusion signals, confirming the presence of MYC rearrangement. The presence of a prominent intravascular in our case is unique. To our knowledge, these findings have not been observed in the previous reports of PBL. The observation of this vascular component supports the heterogeneity of PBL and may be an indicator of tumor aggressiveness. We were able to demonstrate the MYC/IGH rearrangement in our case of PBL. The interplay between Epstein-Barr virus and this MYC rearrangement may be similar to what is observed in Burkitt lymphoma, another clinically aggressive non-Hodgkin lymphoma.  相似文献   
89.
This study investigated the morphometric changes, biochemical parameters, and kidney morphology of male West African Dwarf goats exposed to graded levels of 2,4-dichlorophenoxyacetic acid (2,4-D). Four groups of five goats were used for this experiment. Goats in three of the groups were exposed to oral administration of 2,4-D as follows: group A, low dose (75 mg/kg body weight); group B, medium dose (100 mg/kg body weight); and group C, high dose (125 mg/kg body weight); every 72 h for a period of 112 days. The group D goats served as the control and received no 2,4-D treatment. Morphometric changes, biochemical parameters, and histomorphological features of the kidney of goats exposed to 2,4-D were compared with control goats. Exposing male goats to 2,4-D treatment led to reduction in mean body weights (p < 0.05), mean blood glucose (p < 0.05), and mean total serum protein (p < 0.05) concentrations. The histomorphology of the kidney sections of the 2,4-D-treated goats was that of subacute to chronic exudative glomerulonephritis; and the severity of lesions increased with higher 2,4-D concentration. It was concluded that exposing male West African Dwarf goats to varied concentrations of 2,4-D herbicide resulted in reduction in weight gain, changes in blood glucose and total serum protein concentrations, as well as glomerular, tubular, and interstitial lesions in the kidney.  相似文献   
90.
BACKGROUND: Aging is associated with diminished baroreflex sensitivity (gain), which predisposes elderly people to orthostatic hypotension, syncope, and cardiovascular morbidity. Aging is also associated with systolic blood pressure (SBP) elevation and carotid artery stiffness, which may both affect baroreflex gain. METHODS: We examined the relation between SBP, carotid artery stiffness, and baroreflex gain in 34 healthy elderly (71 +/- 4 years) and 10 healthy young (31 +/- 3 years) subjects. SBP (Finapres) and carotid artery stiffness (ultrasound measures of relative carotid artery diameter changes during each blood pressure pulse) were measured. The gain of the transfer function relating the R-R interval to SBP fluctuations at a frequency of 0.05-0.15 Hz was used to assess cardiovagal baroreflex gain. RESULTS: Elderly subjects had higher carotid artery stiffness (14.2 +/- 5.1 vs 6.6 +/- 1.8, p <.05), higher SBP (146 +/- 24 vs 125 +/- 8 mmHg, p =.012), and lower baroreflex gain (8.2 +/- 6.4 vs 16.3 +/- 7.4, p <.05) than young subjects. Among all subjects, SBP and carotid artery stiffness both correlated with baroreflex gain (r = -.39, p =.02 for both). Although SBP was related to stiffness across all subjects, this relation was not present among the elderly subjects. Within the elderly group, only SBP was independently related to baroreflex gain (R(2) =.51, p =.009). CONCLUSIONS: SBP elevation in elderly people may affect the neural or cardiac response to blood pressure fluctuations, independent of the mechanical properties of barosensory regions in the carotid artery. Future studies should examine the effect of pharmacologic treatment of hypertension on baroreflex gain in elderly people.  相似文献   
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