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261.
G. S. Dogra 《Journal of morphology》1967,121(3):223-239
With the help of PF and PAVB bulk-stained preparations and sections the neurosecretory system of Ranatra elongata has been described. Two medial, each of 9-10 cells, and two lateral, each of 3-4 cells, groups of neurosecretory cells have been observed in the protocerebrum. Only the A-cells have been found to be positive to PAVB histo- and cyto-chemical technique. Axons of the A-cells after traversing the proto- and deuto-cerebrum emerge from the tritocerebrum as the NCC I. The NCC I after bypassing the corpora cardiaca penetrate the aorta wall. There is no physical continuity between the corpora cardiaca and the NCC I and the two are separable. The NSM from the A-cells, transported by their nerve fibers, has been observed in the aorta wall. On the basis of large accumulation on NSM in the aorta wall the latter has been considered as the storage-and-release organ for the A-material. Corpora cardiaca are found to be devoid of A-material. Axons from the B-cells, after emergence from the tritocerebrum as the NCC II, have been observed to penetrate the corpora cardiaca. On the basis of ample amounts of B-material the glands have been considered as the storage-and-release organ for the B-material only. Observations are compared with results on related species and it is concluded that two independent organ complexes constitute the neurosecretory systemt of R. elongata. The A-cells, their pathways, the NCC I, and the aorta wall comprise the first; and the B-cells, their pathways, the NCC II, and the corpora cardiaca the second. The former is concerned with the elaboration, transportion, storage-and-release of the A-material and the latter with the B-material. Finally arguments are presented to include the aorta wall in the neurosecretory system. 相似文献
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263.
In order to study the progress of pulmonary silicosis in rats of different ages, intratracheal injections of (50 mg/150 g body weight) quartz dust of particle size less than 5 mu were given as a single dose and studies were made over a period of 180 days. The pulmonary macrophage reaction and phagocytosis in the younger age group of rats was different from that in the older animals at 30 days postinoculation. The formation of silicotic nodules was delayed in the younger animals. They consisted of thick reticulin fibers and some collagen fibers; in the older group of rats large silicotic nodules with dense collagination developed towards the termination of the experiment (180 days). The present results indicate a possible direct relationship between age and the development of experimental pulmonary silicosis in rats. 相似文献
264.
265.
Inducers of nod genes of Rhizobium ciceri. 总被引:2,自引:0,他引:2
Induction of nodABC genes of R. ciceri was studied by constructing nodABC-lacZ fusion. The root exudates of the homologous hosts induced the expression of nodABC genes but those of heterologous hosts failed to do so. The HPLC analysis of the root exudates of C. arietinum showed the presence of 6-7 compounds with retention times matching to flavonoids like naringenin, hesperetin, daidzein, naringin, 7 OH coumarin and luteolin. Induction studies using the standard flavonoids showed naringenin, followed by daidzein, as most potent inducer of the nodABC genes of R. ciceri. Naringenin in combination with daidzein showed a synergistic effect on the expression of nodABC genes. 相似文献
266.
267.
Neuroendocrine system of the sugarcane leaf hopper, Pyrilla perpusilla, has been studied by employing PAVB and AF techniques in situ and on sections. There are four groups of NS cells in the brain, a medial of 14--17 cells, lateral and an antero-ventral of 2 cells each and a latero-ventral of a single cell. The cells are of A and B types: tinctorially the A-cells are further subdivided into A1, A2 and A3 subtypes. Suboesophageal and thoracic ganglions have 2 groups of 2 and 3 cells, each of A and B types. Axons of the cells of cerebral groups converge to form a common pathway which emerge from the protocerebrum as NCC. NSM transports both inter and intracellularly. In CC stained colloids accumulate at the commissuris, the gland has two--A and B--types of intrinsic cells. CA is devoid of NSM. Though considerably small in size and have new NS cells, its NS pathways are easily demonstrated in situ. It is emphasized that size and number of neurosecretory axons is not a limitation of the in situ technique but the demonstration of the tract depends upon the physiological state of the animal at the time of fixation. 相似文献
268.
Cutaneous leishmaniasis (CL) is a vector-borne parasitic disease of the skin. Previous open controlled studies with oral itraconazole suggest that it was effective for CL in India. Twenty patients with localised CL participated in this trial. Patients were allocated randomly to receive capsule itraconazole and matching placebo for 6 weeks. No topical medicines were used. Demonstration of Leishmania by slit smear was mandatory. Prior to, periodically during and 3 months after completion of therapy an overall clinical assessment, liver function tests and urinalysis were performed. On decoding, out of the 10 cases receiving drug itraconazole, 7 were declared cured by clinical and parasitological criteria. No major side-effects were noted. Spontaneous remission was observed in 1 case in the placebo group at 3 months follow up. Oral itraconazole has a promising antileishmanial potential and may thus secure CL patient from the hazards of antimonials. 相似文献
269.
Jenny Shaw Tim Amos Isabelle M Hunt Sandra Flynn Pauline Turnbull Navneet Kapur Louis Appleby 《BMJ (Clinical research ed.)》2004,328(7442):734-737
Objectives To establish changes over time in the frequency of homicides committed by strangers, and to describe the personal and clinical characteristics of perpetrators of stranger homicides.Design Longitudinal study and national clinical survey.Participants People convicted of homicide in England and Wales between 1996 and 1999 and whether the victim was known to the perpetrator.Setting England and Wales.Main outcome measure Characteristics of perpetrators of homicides according to whether victims were strangers or not.Results Stranger homicides increased between 1967 and 1997, both in number and as a proportion of all homicides. No increase was found, however, in the number of perpetrators placed under a hospital order after homicide, whether all homicides or stranger homicides only. 358 of 1594 (22%) homicides were stranger homicides. In these cases the perpetrator was more likely to be male and young. The method of killing was more likely to be by hitting, kicking, or pushing (36% (130 of 358) for victims who were strangers to the perpetrator compared with 14% (145 of 1074) for victims who were known). Perpetrators were less likely to have a history of mental disorder (34%, n = 80 ν 50%, n = 142), a history of contact with mental health services (16%, 37 of 234 ν 24%, 200 of 824), and psychiatric symptoms at the time of the offence (6%, n = 14 ν 18%, n = 143). They were more likely to have a history of drug misuse (47%, n = 93 ν 37%, n = 272); alcohol (56%, n = 94 ν 41%, n = 285) or drugs (24% n = 44 ν 12%, n = 86) were more likely to have contributed to the offence.Conclusions Stranger homicides have increased, but the increase is not the result of homicides by mentally ill people and therefore the “care in the community” policy. Stranger homicides are more likely to be related to alcohol or drug misuse by young men. 相似文献