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1.
Abstract Substance P is a neuropeptide which is present in peripheral C nerve endings and released from them. Free nerve endings of C nerve are present in human epidermis. The effects of substance P on the transmembrane signaling system of pig epidermal sheets were previously reported. In these studies, a small amount of cells other than keratinocytes contaminated the epidermal sheets and the species difference from human was also noticed. Therefore we investigated the effects of substance P on cultured normal human epidermal keratinocytes. Alteration of intracellular free calcium (Ca2+) in single living keratinocytes was studied using an inverted fluorescence microscope and Ca2+ -sensitive dye, Fura 2-AM. Treatment of normal human epidermal kertinocytes with substance P resulted in an increase in inositol 1,4,5-trisphosphate and in intracellular Ca2+. Substance P inhibited DNA synthesis of the keratinocytes in a dose-dependent manner. These results are consistent with the view that substance P stimulates phosphatidylinositol-4,5-bisphosphate hydrolysis of human keratinocytes, resulting in inositol 1,4,5-trisphosphate-Ca2+ signal.  相似文献   
2.
Forty-five patients with mild hypertension were treated for 2 months with either metoprolol or pindolol in a randomized, blind, crossover study. The effects of metoprolol (100-300 mg/day) and pindolol (5-15 mg/day) on triglyceride (TG), cholesterol (C), high-density lipoprotein cholesterol (HDL-C), and HDL subfraction (HDL2-C and HDL3-C) levels were compared in males and females separately. Pindolol and metoprolol significantly elevated (10% above baseline level) the plasma TG level in both males and females. After metoprolol treatment, the HDL-C level remained unchanged in both sexes; however, a shift was found between HDL2-C and HDL3-C:HDL2-C decreased and a concomitant elevation in HDL3-C was observed. Pindolol significantly decreased total C, HDL-C, and HDL2-C levels in males. A similar trend (although the changes were not significant) was found in females. The results demonstrate the role of beta blockers in the inhibition of TG-rich lipoprotein elimination. These findings suggest that during long-term administration of metoprolol and pindolol, risks and benefits from beta-blocker therapy must be carefully considered. Continuous monitoring of lipid profiles is suggested during this treatment in order to avoid the potential worsening effect of beta blockers on risk factors of ischemic heart disease.  相似文献   
3.
An attempt was made to determine the normal reference values of lipid- and lipoprotein levels (cholesterol), triglycerides, cholesterol in high- and low-density lipoproteins) in a selected, apparently healthy, Cuban population. Results were expressed as mean, and various percentiles of measured values; two ratios: Risk 1 (LDL-C/HDL-C) and Risk 2 (TC/HDL-C) were also calculated. Approximately 40% of the subjects aged 20 to 30 years had cholesterol values above 200 mg/dl. Females had significantly higher cholesterol HDL-C values than males, whereas the concentrations of LDL-C and LDL were higher in males. Risk 2 ratios were elevated in males. A correlation was shown between lipid levels and age. There was a strong negative correlation between HDL-C and relative body weight. It is suggested that obesity might be an individual risk factor in the population studied.  相似文献   
4.
We determined the lipid and lipoprotein levels in a selected group of apparently healthy adult Cuban subjects in a previous paper /27/. In this paper the basic lipid variables (TC, TG, HDL-C) in 271 healthy children are published. LDL-C levels were also calculated. A small, but continuous, rise was found in the TC level between 0 and 14 years in both sexes. The rise of TG was accompanied by HDL increase in girls but by LDL increase in boys. This phenomenon might explain the augmented susceptibility of men to ischaemic heart disease. Children at "high risk" should be identified (in case of positive family history of ischaemic heart disease) by cholesterol determinations, the borderline of the pathologic cholesterol levels seems to be very similar to that found in the USA, 170-190 mg/dl in the age group between 0 and 14 years.  相似文献   
5.
The influence of free radicals on apoptosis was studied in the human heart; 45 autopsy cases were examined by the nick end labelling method (NELM) that detects DNA fragmentation. Immunostaining for copper-zinc superoxide dismutase (CuZn-SOD) and tissue transglutaminase (tTG) induced frequently during apoptosis were also studied. Positive immunoreaction for tTG was detected in mucinous degeneration of myocardial cells; these same cells were also positive for CuZn-SOD but negative for NELM. Myocardial cells showing basophilic alterations after haematoxylin and eosin staining were also positive for CuZn-SOD but negative for the other markers examined. Positive nuclear reaction by NELM was only observed in myocardial cells showing contraction band necrosis or irregularly shaped nuclei surrounding recent or long-standing infarcted foci. In these the other two markers were negative. Since mucinous degeneration lacks the distinguishing morphological features of apoptosis, immunoreactive tTG in this lesion may not imply that the cells are undergoing apoptosis. tTG can be induced in non-apoptotic conditions and may not be involved in apoptosis induced by infarction. Histological disassociation between CuZn-SOD expression and apoptosis suggests the possibility of a cytoprotective role played by endogenous CuZn-SOD against free radical generation in the human heart.  相似文献   
6.
Botulism in humans is caused by botulinum neurotoxins, produced in most cases by Clostridium botulinum, although other Clostridia species are implicated as well. Of the five forms of botulism in humans, three are referred to as “infective”: wound botulism, infant botulism, and adult intestinal botulism; the latter two forms are also referred to as “intestinal toxemia botulism” because the organism colonizes the lumen of the intestinal tract and produces botulinum neurotoxin in vivo. Twenty-three cases of infant botulism and three cases of adult intestinal botulism occurred in Italy between 1984 and 2005. Microbiological analyses of clinical, environmental, and food samples and analysis of clinical and epidemiological data revealed two main characteristics of intestinal toxemia botulism in Italy that are not common in cases in other countries: the isolation of a strain of C. butyricum that produced botulinum neurotoxin type E in 6 of 26 cases, including two cases of adult intestinal toxemia botulism, and the onset of botulism in these cases with concomitant severe gastrointestinal symptomatology. This report summarizes the microbiological, clinical, and epidemiological data of all cases of intestinal toxemia botulism that have occurred in Italy in the period 1984–2005.  相似文献   
7.
The apparent causative organism from the only reported case of type E infant botulism was isolated and characterized. Except for its ability to produce type E botulinal toxin, this organism (strain 5262) would be unquestionably identified as Clostridium butyricum. This is the second time an organism resembling a defined Clostridium species other than a member of the C. botulinum group has been implicated in infant botulism.  相似文献   
8.
A case of infant botulism in a 9 week-old female is described. A strain of C. botulinum type B was isolated from the feces of the baby. The epidemiologic study detected in a sample of home canned honey Clostridium botulinum spores of the same serotype that was isolated from the patient. The honey had been used only to sweeten the pacifier of the baby. This is the first case of infant botulism in Europe linked conclusively to honey.Corresponding author.  相似文献   
9.
70 patients suffering from multiple myeloma were observed by authors in the last 15 years and three months. In the meantime fifty-two out of them have died, and 18 patients are under permanent care. 43 IgG, 17 IgA, 6 Bence-Jones, 2 IgD types were diagnosed according to the paraprotein distribution, one patient proved to be nonsecretory, and an other one to osteosclerotic form as well. The median survival time was 27 months in the group of deceased patients. In the group followed-up 50.8 months survival time was observed up to the closing of the study. Several prognostic factors were investigated. According to the classification by Durie and Salmon the survival time was 60 months in the patients with stage I, 33 months in stage II., and 9 months in stage III respectively. The prognosis is much poorer in patients into the "B" category: the survival time was 14 months. Classified in the basis of the type of the myeloma-cell, the cases with well matured cells have had the best prognosis with survival time of 46 months, while the most unfavourable prognosis was observed in patients with blast-cell type, with a median survival time of 10 months. The greatest number of patients suffered from multiple myeloma of IgG paraprotein type, in this group the serum IgA level was found to be significantly decreased in the patients died due to inevitable infections. The survival was injured significantly by the occurrence of concomitant severe diseases, to.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
10.
Eight 12 month-olds acting on objects were observed in two sessions: 1) the objects were home objects; 2) they were brought by the observer as new exemplars of previous toys. Infants were observed manipulating objects independently and with their mothers. Type and cognitive level of infant's actions were coded. Conventional actions were more frequent in joint than independent activity. In independent activity, conventional actions were more frequent with customary objects. High cognitive level was more frequent with customary objects. Acting with an adult is the major influential factor in promoting conventional usage of an object. However, acting on customary objects influences both conventional usage and organization of the actions. Notion of joint activity as a social practice rather than interactional event can be useful in accounting for this influence.  相似文献   
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