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61.
Insulin release from pancreatic islets is impaired in chronic renal failure (CRF), and this is due to the state of secondary hyperparathyroidism of CRF. This defect in association with resistance to the peripheral action of insulin-caused glucose intolerance in CRF. It has been suggested that the impaired insulin release induced by excess parathyroid hormone (PTH) is related to the ability of the hormone to augment calcium entry into the pancreatic islets, resulting in accumulation of calcium in the pancreas. Therefore, a calcium channel blocker may antagonize this effect of PTH, and hence normalize glucose tolerance in CRF. The present study examined this postulate by studying intravenous glucose tolerance and insulin release from pancreatic islets in normal and CRF rats and in CRF animals treated with the calcium channel blocker, verapamil. Rats with 42 days of CRF displayed impaired glucose tolerance, significant reduction (P less than 0.01) in insulin release by islets, and doubling of calcium content of the pancreas (P less than 0.01) as compared to normal rats. Simultaneous treatment of CRF rats with verapamil for 42 days resulted in normal glucose tolerance, higher blood insulin levels during glucose infusion, normal calcium content of the pancreas, and normal insulin secretion by the islets. Treatment of normal rats with verapamil for 42 days did not affect any of the parameters studied. The results show that the calcium channel blocker, verapamil, by preventing calcium accumulation in the pancreas, reversed the abnormalities in insulin release that occur in CRF. This effect allowed a greater rise in blood levels of insulin during glucose infusion in CRF rats.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
62.
The hormonal environments require by human breast cancer cells MCF-7 to produce solid tumors in nude mice are described. A 100% take was obtained within 7 days following inoculation of 2X10(6) actively growing (log phase) MCF-7 cells into the mammary fat pads of intact, athymic BALB/c nude mice. Tumors failed to develop, even with an inoculum of 20X10(6) cells/mouse, in ovariectomized mice or in mice made diabetic with streptozotocin and observed for 90 days after cell inoculation. A 100% incidence of tumors was obtained in mice that were either hypophysectomized or made diabetic but received injections of 0.2 IU insulin/day/mouse. A 100% incidence of tumors was also obtained in ovariectomized mice that received 17 beta-estradiol in the form of a pellet placed subcutaneously in the interscapular region at the time of cell inoculation. Palpable tumors also developed in ovariectomized mice treated with prolactin, perphenazine, estrone, or estriol, but no takes were observed in ovariectomized mice treated with progesterone, 5 alpha-dihydrotestosterone, or hydrocortisone. Growth of the MCF-7 tumor was stimulated five- to sixfold in both intact and hypophysectomized mice that each received a 17 beta-estradiol pellet. Removal of the 17 beta-estradiol pellets form tumor-bearing ovariectomized mice failed to induce tumor regression. Tumors that continued to grow in ovariectomized mice deprived of 17 beta-estradiol regressed by 50% or more of their initial volume when tamoxifen was injected for 7 days at 5 micrograms/mouse/day) +/- theophyline (1 mg/mouse/day), tumor growth arrest was observed during the 2-to 3-week treatment period. Streptozotocin-induced diabetes in tumor-bearing mice always resulted in complete tumor regression following a 3-week treatment period.  相似文献   
63.
We report case of extrinsic compression of the left brachiocephalic vein by the innominate resulting in massive edema of the arm in a patient with hemodialysis Gore-Tex graft. To our knowledge, such phenomenon has not been previously reported.  相似文献   
64.
Exophiala (Wangiella) dermatitidis is a melanised (darkly pigmented) yeast-like organism that has been reported from the environment and wild animals. The organism is a frequent coloniser of lungs of patients with cystic fibrosis and causes occasional disseminated phaeohyphomycosis and fungaemia. Exophiala dermatitidis is distributed worldwide, but cerebral cases are restricted to East Asia. We report a case of 54-year-old Qatari female patient with a known history of cancer, suffering from pulmonary disorder. Culture of endotracheal aspirate revealed the growth of E. dermatitidis concomitant with Candida krusei. The final diagnosis of E. dermatitidis and attribution to genotype B was achieved by sequencing the rDNA internal transcribed spacer (ITS) region. The present case concerns a pulmonary colonisation by E. dermatitidis, similar to that commonly seen in cystic fibrosis patients. For the detection of E. dermatitidis in clinical specimens culturing techniques are required. The patient finally expired with persistent cancer and C. krusei fungaemia. Review of literature and listing of E. dermatitidis cases published after 1992 show a sharp increase in clinical cases during the 1990s.  相似文献   
65.
PURPOSE: To document intrafamilial and interocular phenotypic variability of autosomal dominant cataract (ADC). DESIGN: Prospective observational case series. METHODS: We performed ophthalmologic examination in four Chilean ADC families. RESULTS: The families exhibited variability with respect to morphology, location with the lens, color and density of cataracts among affected members. We documented asymmetry between eyes in the morphology, location within the lens, color and density of cataracts, and a variable rate of progression. CONCLUSIONS: The cataracts in these families exhibit wide intrafamilial and interocular phenotypic variability, supporting the premise that the mutated genes are expressed differentially in individuals and between eyes; other genes or environmental factors may be the bases for this variability. Marked progression among some family members underscores the variable clinical course of a common mutation within a family. Like retinitis pigmentosa, classification of ADC will be most useful if based on the gene and specific mutation.  相似文献   
66.
67.
A 28-year old Malay man with evidence of an upper motor neuron cord lesion was diagnosed to have a C7 to T2 spinal arterio-venous malformation and associated cutaneous vascular lesion. He finally agreed for treatment after 5 years of progressive spastic right lower limb weakness leading to inability to mobilize. A two staged intravascular procedure was done followed by surgery with recovery of ASIA impairment scale grade B.  相似文献   
68.
The intracellular specific 17beta-estradiol binding in the human breast cancer cell line, MCF-7, was shown to be modified by prolactin. Both ovine and human prolactin doubled the estradiol receptor (E2R) level, but the latter was at least 10 times more stimulatory on a concentration basis. Most of the E2R complex (approximately 80%) was transported to the nucleus, and the prolactin stimulation was reflected in an elevated nuclear uptake of the tritiated 17beta-estradiol. Neither ovine nor human prolactin altered the growth rate of the cells when E2R stimulation was maximal. Insulin (10 mug/ml) stimulated tritiated thymidine incorporation and total DNA content but had no apparent effect on E2R concentration. At 10(-4) M, N6,O2'-dibutyrylcyclicadenosine 3':5'-monophosphate increased insulin stimulation of tritiated thymidine incorporation and brought about a prolactin stimulation of apparent DNA synthesis. Theophylline (10(-3) M) blocked both of these effects of N6,O2'-dibutyrylcyclicadenosine 3':5'-monophosphate. The possible mechanism implicating prolactin as an effector of differentiation and growth of MCF-7 cells is discussed.  相似文献   
69.
A 35 years old lady presented with history of something coming out of the genitalia for the last 5 days. She also had history of pain in the left lumbar region which was initially investigated but the patient did not follow-up. About 15 years ago she also underwent left ureteric reimplantation. On examination, a stick like tube was protruding out of the urethral meatus which was fixed to the underlying vesical calculus. The calculus was evident radiologically and on ultrasound. The projecting portion of the stick like tube was cut and the vesical calculus with the inner portion of the tube was removed by open procedure. On evaluation of the specimen, it was found that the vesical calculus was fixed to the plastic tube which had concretions around it. This plastic tube had been placed after the ureteric reimplantation done 15 years ago and the patient was not aware of it.  相似文献   
70.

Introduction

The aim of this study was to evaluate and compare the antimicrobial activity of calcium hydroxide, triantibiotic mixture (TAM), and an ethanol extract of propolis as intracanal medicaments on Enterococcus faecalis-infected root canals.

Methods

One hundred twenty extracted intact human permanent incisors were decoronated, and chemomechanical preparation of the root canal was performed. After sterilization of the samples, they were inoculated with pure culture of E. faecalis and incubated. After incubation, colony-forming units were recorded before medication. Then, samples were divided randomly into five groups (n = 24). Each group was then exposed to various intracanal medicaments, namely calcium hydroxide (group 1), TAM (group 2), propolis (group 3), ethanol (group 4), and saline as the control group (group V). The antibacterial effectiveness of the different intracanal medicament was recorded by determining the percentage reduction in colony counts (%RCC) at the end of days 1, 2, and 7. The data were statistically analyzed using one-way analysis of variance and Tukey Honestly Significant Difference (HSD) post hoc test.

Results

The %RCC was highest for propolis showing 100% reduction on day 2 followed by TAM showing 82.5%, 92.2%, and 98.4% of reduction on days 1, 2, and 3, respectively. Calcium hydroxide showed a gradual increase in antibacterial activity with a maximum of 59.4% on day 7.

Conclusions

Propolis was more effective than TAM against E. faecalis at a 2-day time period, and both were equally effective at 7 days.  相似文献   
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